## Appendix 2: Mass scattering efficiencies and corres ponding Notes notes tables and citation list.

Table 2. Summary of a literature survey of mass scattering e fficiencies using the theoretical method. The first column corresponds to the reference number an d entry in the associated notes table. Entries corr espond to the fine mode unless otherwise stated in the col umn heading, or noted with superscripts.



## Theoretical Method Mass Scattering Efficiency (m 2 

## g - 1 

## ) *

Note Fine Mode Coarse

Mode Total

Mode Sulfate POM Dust Sea Salt Location/ Study/ Characteristic Time

1 1 1.4 ± 0.7 Baltimore, MD Canadian smoke (Supersite) Jul

4,6,10 2002

3 2 3.8 2.8 † Great Smoky National Park, TN (SEAVS) Jul-Aug

1995

10 3 1.07 ♦ 0.52 ♦ Sal Island, Cape Verde Dec

1991, Jan 1994, Dec 1994- Feb 1995

17 3.4 0.6 Big Bend National Park, TX (BRAVO) Jul-Oct

1999

19a 4 3 0.9 † Santa Maria, Azores Jun 10,

1992

19b 4 28 2.4 † Santa Maria, Azores Jun 13,

1992

19c 4 13 3.3 † Santa Maria, Azores Jun 19,

1992

19d 4 9.1 2.5 † Santa Maria, Azores Jun 20,

1992

19e 4 5.2 1.6 † Christmas Island Aug 3,

1994

22 5 6.9 6.0 †, ♦ 5.3

2.9 0.64 ‡ 1.3 ‡ Waliguan Mountain, Qinghai Province, China Oct-Nov

1997, Jan 1998

29a 2.23 Hopi Point, Grand Canyon National Park, AZ Jan-Feb

1998

29b 2.59 Hopi Point, Grand Canyon National Park, AZ Jan-Feb

1998

29c 4.81 Hopi Point, Grand Canyon National Park, AZ Jan-Feb

1998

29d 2.03 Meadview, AZ Summer 1992
29e 2.05 Meadview, AZ Summer 1992
29f 2.11 Meadview, AZ Summer 1992Note Fine Mode Coarse

Mode Total

Mode Sulfate POM Dust Sea Salt Location/ Study/ Characteristic Time

29g 2.63 Shenandoah National Park, VA Summer

1990

29h 3.81 Shenandoah National Park, VA Summer

1990

29i 18.23 Shenandoah National Park, VA Summer

1990

31a 2.4 Great Smoky National Park, TN (SEAVS) Jul-Aug

1995

31b 3.58 Great Smoky National Park, TN (SEAVS) Jul-Aug

1995

31c 9.64 Great Smoky National Park, TN (SEAVS) Jul-Aug

1995

32 3.15 2.96 † Big Bend National Park,TX (BRAVO) Jul-Oct

1999

33 4.21 Yosemite National Park, CA (YACS) Jul-Sep

2002

34 6 0.48 ‡ Izana, Tenerife, Canary Islands Jul 1999

37 4.3 Yosemite National Park, CA (YACS) Jul-Sep

2002

43 7 3.6 0.87 5 ♦ 2.8 ♦ 3.6 †, ♦

, Pacific Ocean and Cheeka Peak, WA (PSI and MAGE) 1991 &

1992

45 8 3.2±0.3 0.84±0.09, 1.5±0.2, 1.12 † 4.1±0.4 Southern Ocean Region (ACE1) Nov-Dec

1995

46 9 4 ♦ 1.7 †, ♦ 3.3 ♦ 1.1 ♦ 1.6 ♦ Norfolk, VA to Cape Town, South Africa (Aerosols99) Jan–Feb

1999

46 10 4.8±0.5 3.5±0.7 4.4±0.9, 1.83 † 6.4±1.1

7.2±1.8 3.6±0.8 6.0±0.7 Norfolk, VA to Cape Town, South Africa (Aerosols99) Jan–Feb

1999

46 11 1.02±0.05 1.7±0.4 1.9 ±0.5 ‡ 0.60±0.07 ‡ 1.12±0.16 ‡ Norfolk, VA to Cape Town, South Africa (Aerosols99) Jan–Feb

1999

48 12 4.9 ♦ 2.04 †, ♦ 4.1 ♦

3.6 ♦ 1.5 ♦ 1.6 ♦ Indian Ocean (INDOEX) Feb-Mar

1999

48 13 4.5±0.5 3.9±0.8 5.0±0.9, 2.06 † 6±1

5±1 3.4±0.4 5.5±0.3 Indian Ocean (INDOEX) Feb-Mar

1999

48 14 2±1 3.7±0.6 ‡ 3.9±0.5 ‡

, 1.6 †,‡ 4.1±0.9 ‡

3.6±0.8 ‡ 0.8±0.3 ‡ 1.06±0.7 ‡ Indian Ocean (INDOEX) Feb-Mar

1999Note Fine Mode Coarse

Mode Total

Mode Sulfate POM Dust Sea Salt Location/ Study/ Characteristic Time

49 15 4.3±0.6 3.8±0.7 2.5±0.3 † 5.3±0.7

4.7±0.6 3.4±0.3 5.0±0.5 Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

49 16 1.4±0.6 3.2±0.4 ‡ 2.0±0.3 ‡ 1.8±0.2 ‡ 0.67±0.16 ‡ 1.6±0.2 ‡ Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

49 17 3±1 ♦ 3.7±0.6 ♦ 4.4±0.7 ♦ 3.9±0.6 ♦ 1.2±0.4 ♦ 2.8±0.4 ♦ Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

Footnotes for theoretical method table *All values reported for a wavelength of 550 nm unl ess otherwise stated in the Theoretical method note table. Values correspond to fine mode unless otherwise noted in t he column header or by foot note. Size ranges and r elative humidity (when reported) are stated in the Theoretical metho d note table or in the footnotes. Theoretical metho d includes mixed (‘specific’), externally mixed, and mixed/apportion ed methods, also found in the Theoretical method no te table for each entry.

In the “sulfate” column, italicized values correspo nd to dry ammonium sulfate. In the “POM” column, italicized values are normaliz ed to POM multiplier of R oc = 1.8.

† We converted to dry ammonium sulfate ‡ Corresponds to coarse mode (supermicron)

♦ Corresponds to total modes (supramicron, fine + co arse)

1 Average and standard deviation of three time period s (see notes 1a, 1b, and 1c).
2 Sulfate is ion, Dp < 3 μm
3 Dust and sea salt are for Dp < 8.75.
4 Sulfate is ion for 0.18 < Dp < 10 μm 5 Sulfate is bisulfate in the accumulation mode. Org anic carbon is in the accumulation mode. Dust and s ea salt correspond to coarse mode. 6 Dust is coarse mode.
7 Sulfate is ion and sulfate aerosol (nss-SO4+NH4+ H 2O), and corrected dry ammonium sulfate aerosol. re spectively, for Dp < 10 um. Mixed fine corresponds to residual mass for Dp < 1 μm and mixed coarse corresponds to residual mass for 1 < Dp < 10 μm (see notes 43a and 43b).
8 Dp < 1 μm. Average and standard deviation of estim ates corresponding to air masses for short (< 5 day s), long (>= 5 days) marine boundary layer residence times, and perturbe d air masses. Sulfate is dry (30-45%) ammoniated su lfate mass, sulfate ion and corrected dry ammonium sulfate from ion, respec tively (see notes 45a-f).
9 Sulfate is ion, and corrected dry ammonium sulfate . Dp < 10 μm (see note 46a), RH = 55 %.
10 Dp < 1.1 μm. Average and standard deviation of val ues corresponding to North America, Northern Hemisp here marine, African dust, African dust/biomass burning, and bio mass burning. Sulfate is wet ammoniated sulfate mas s (55 % RH), sulfate ion and corrected dry ammonium sulfate from ion, respec tively, (see notes 46a-k).
11 1.1 < Dp < 10 μm. Average and standard deviation o f values corresponding to North America, Northern H emisphere marine, African dust, African dust/biomass burning, and bio mass burning. Sulfate is wet ammoniated sulfate mas s (55 % RH), sulfate ion and corrected dry ammonium sulfate from ion, respec tively (see notes 46l-p).
12 Dp < 10 μm. Sulfate is ion (see note 48a).
13 Dp < 1.1 μm. Average and standard deviation of val ues corresponding to SH Atlantic, SH Indian Ocean, NH Indian Ocean, East Indian Subcontinent, Indian Subcontinent, Arab ia, Arabian-Indian Subcontinent and Arabian Sea-Coa stal India. Sulfate is wet ammoniated sulfate mass (55 % RH), sulfate ion and corrected dry ammonium sulfate from ion, respec tively (see notes 48aq).
14 1.1 < Dp < 10 μm. Average and standard deviation o f values corresponding to SH Atlantic, SH Indian Oc ean, NH Indian Ocean, East Indian Subcontinent, Indian Subcontinen t, Arabia, Arabian-Indian Subcontinent and Arabian Sea-Coastal India. Sulfate is wet ammoniated sulfate mass (55 % RH), s ulfate ion and corrected dry ammonium sulfate from ion, respectively (see notes 48r-cc). 15 Dp < 1.1 μm. Average and standard deviation of val ues corresponding to Polluted-Korea/Japan, Polluted -Japan, Volcano+Polluted, dust+Frontal, Dust+Korea, and Dus t+Shanghai. Sulfate is sulfate aerosol (nss-SO4+NH4 +H2O, RH = 55 %) and corrected to dry ammonium sulfate (see notes 49 a-f).16 1.1 < Dp < 10 μm. Average and standard deviation o f values corresponding to Polluted-Korea/Japan, Pol luted-Japan,

Volcano+Polluted, dust+Frontal, Dust+Korea, and Dus t+Shanghai. Sulfate is sulfate aerosol (nss-SO4+NH4 +H2O, RH = 55 %) (see notes 49g-l).
17 Dp < 10 μm. Average and standard deviation of valu es corresponding to Polluted-Korea/Japan, Polluted- Japan, Volcano+Polluted, dust+Frontal, Dust+Korea, and Dus t+Shanghai. Sulfate is sulfate aerosol (nss-SO4+NH4 +H2O, RH = 55%) (see notes 49m-r).



## Theoretical Method Notes table with further details about measurement methods

Theoretical Method Notes

1a Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 um). Bsp computed with Mie theory at a wavelength at 530 nm. RH values not stated. Values are means. Mixed (‘specific’) method. (July 4 0100 LT - July 6 1900 LT 2002, Baltimore Supersite. Smoke transport from Canada)
1b Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 um). Bsp computed with Mie theory at a wavelength at 530 nm. RH values not stated. Values are means. Mixed (‘specific’) method. (July 6 1905 LT - July 10 2200 LT 2002, Baltimore Supersite. Smoke transport from Can ada)
1c Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 um). Bsp computed with Mie theory at a wavelength at 530 nm. RH values not stated. Values are means. Mixed (‘specific’) method. (July 10 220 5 LT - July 13 0055 LT 2002, Baltimore Supersite. Smoke transport from Can ada)
3 Bsp computed from ASASP-X OPC dry size distributio ns. Sulfate acidity varied. The accumulation mode w as assumed to be all sulfate. Esp computed per mass of sulfate ion. Wave length not stated. Mixed/apportioned method. (July 15 - August 22 1995, Great Smoky Mountains National Park, TN, SEAVS study).
10 Mass size distributions (0.65 < Dp < 8.75 um). Val ues are means. Sulfate corresponds to excess sulfat e ion. Mineral dust is traced by Al. Sea salt derived from sodium based on amount s in sea water. Externally mixed method. Wavelength of 670 nm. (Dec 1991, Jan 1994, Dec 1994-Feb 1995, Sal Island, Cape Verde ).
17 Computed using dry accumulation mode and coarse mo de volume size distribution with Mie theory. Refrac tive indices from an alignment method. Size dependence of Esp reported. Wavelength of 530 nm. Mixed (‘specific’) method. (J uly-Oct 1999, Big Bend National Park, TX).
19a MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 73 %). Sulfate corresponds to n ss-SO4 ion. Externally mixed method. (June 10 0800-1900 1992, Santa Maria, Azores archipelago, clean maritime air)
19b MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 95 %). Sulfate corresponds to n ss-SO4. Externally mixed method. (June 13 2000-0700 1992, Santa Maria, Azores archipelago, drizzle, clean maritime air)
19c MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 81 %). Sulfate corresponds to n ss-SO4. Externally mixed method. (June 19 2000-0700 1992, Santa Maria, Azores archipelago, continental polluted air)
19d MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 77 %). Sulfate corresponds to n ss-SO4. Externally mixed method. (June 20 0800-1900 1992, Santa Maria, Azores archipelago, continental polluted air)
19e MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 69 %). Sulfate corresponds to n ss-SO4. Externally mixed method. (Aug 3 1029-2146 1994, Christmas Isla nd, Republic of Kiribati, low contributions from an thropogenic sources)
22 MOUDI size distributions (0.056 < Dp < 18 um). Sul fate corresponds to accumulation mode NH4 + SO4 as bisulfate. Water soluble OC. Na + Cl (sea salt) associated with coar se mode. Coarse mode dust computed for Ca + CO3. Pa rticle growth by Tang. Median values. RH not stated. Size dependence of Es p reported. Externally mixed method. (Oct - Nov 199 7, Jan 1998,Waliguan Mountain, Qinghai Province, China)
29a DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be dry ammonium sulfate. Esp comput ed for ammonium sulfate mass. Wavelength not stated. Externally mix ed method. Size dependence of Esp observed. (Jan-Fe b 1988, Hopi Point, Grand Canyon, AZ)
29b DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be wet ammonium sulfate. Esp estima ted for wet ammonium sulfate mass and wet bsp (ammonium sulfate + water) Wavelength not stated. Externally mixed method. Si ze dependence of Esp observed. (Jan-Feb 1988, Hopi Point, Grand Canyon, AZ)
29c DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be ammonium sulfate. Enhanced Esp e stimated for dry ammonium sulfate mass and wet bsp. Wavelength not s tated. Externally mixed method. Size dependence of Esp observed. (Jan-Feb 1988, Hopi Point, Grand Canyon, AZ)
29d DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be dry ammonium sulfate. Esp comput ed for ammonium sulfate mass. Wavelength not stated. Externally mix ed method. Size dependence of Esp observed. (Summer 1992, Meadview, AZ)
29e DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be wet ammonium sulfate. Esp estima ted for wet ammonium sulfate mass and wet bsp (ammonium sulfate + water) Wavelength not stated. Externally mixed method. Si ze dependence of Esp observed. (Summer 1992, Meadview, AZ)
29f DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be ammonium sulfate. Enhanced Esp e stimated for dry ammonium sulfate mass and wet bsp. Wavelength not s tated. Externally mixed method. Size dependence of Esp observed. (Summer 1992, Meadview, AZ)

## Theoretical Method Notes

29 g DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be dry ammonium sulfate. Esp comput ed for ammonium sulfate mass. Wavelength not stated. Externally mix ed method. Size dependence of Esp observed. (Summer 1990, Shenandoah National Park, VA)
29h DRUM sulfur size distributions for Dp < 2.5 um. Su lfur assumed to be wet ammonium sulfate. Esp estima ted for wet ammonium sulfate mass and wet bsp (ammonium sulfate + water) Wavelength not stated. Externally mixed method. Si ze dependence of Esp observed. (Summer 1990, Shenandoah National Park, VA)

29i DRUM sulfur size distributions for Dp < 2.5 um. Sul fur assumed to be ammonium sulfate. Enhanced Esp es timated for dry ammonium sulfate mass and wet bsp. Wavelength not s tated. Externally mixed method. Size dependence of Esp observed. (Summer 1990, Shenandoah National Park, VA)
31a Drum size distributions (PM2.5) for dry ammonium s ulfate and calculated Bsp. Wavelength not stated. E xternally mixed method. (July 15 - Aug 25, 1995, Great Smoky National Park, TN)
31b Drum size distributions (PM2.5) for wet ammonium s ulfate and calculated wet Bsp, at ambient humidity. Wavelength not stated. Externally mixed method. (July 15 - Aug 25, 1995, G reat Smoky National Park, TN).
31c Drum size distributions (PM2.5) for water enhanced ammonium sulfate at 75% humidity (dry ammonium sul fate mass and wet Bsp). Externally mixed method. Wavelength not state d. (July 15 - Aug 25, 1995, Great Smoky National Pa rk, TN)
32 MOUDI size distributions (0.18 < Dp < 18 um) of dr y ammoniated sulfate mass. Exact form of sulfate no t specified. Externally mixed method. Size dependence of Esp observed. (Jul y-Oct 1999, Big Bend National Park, TX)
33 DMA dry size distributions of accumulation mode. M ixed (‘specific’) method. (July-Sept 2002, Yosemite National Park, CA)

34a APS and SMPS size distributions (Dp < 15 um) for d ust, assuming Dp < 0.6 is non-dust and the rest is dust. Mixed (‘specific’) method. (July 3- 29 1999, Izana, Tenerife, Canary I slands)
37 DMA and OPC dry aligned size distributions (0.04 < Dp < 2 um) and retrieved refractive indices. Wavel ength not stated. Mixed (‘specific’) method. (July-Sept 2004, Yosemite Nati onal Park, CA)
43 DMA and APS number distributions, RH = 30 %. Sulfat e corresponds to sulfate ion for Dp < 10 um. (April - May 1991, Cheeka Peak, WA). Mixed fine corresponds to residual mass (Dp < 1 um). Total corresponds to super micron (1 < Dp < 10 um) residual mass. Mixed/apportioned method. (1991 & 1992, PSI a nd MAGE samples).
43b DMA and APS number distribution, RH = 30 %. Sulfat e corresponds to sulfate aerosol. Mixed/apportioned method (Feb-March 1992, PSI and MAGE samples, Pacific Ocean from 33 N to 12 S along 140 W)
45a Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to (nss -SO4+NH4+H20). Mixed Fine corresponds to Dp < 1 um and (sea salt + nss-s o4).Sea salt corresponds to Dp < 1 um and Na+K+Mg+C a+Cl+ss-SO4). Mixed/apportioned method (Nov-Dec 1995, 41 deg sout h to 54 south, 135 east to 160 east, for Marine air , short (<5 days) marine boundary layer residence time)
45b Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to (nss -SO4+NH4+H20). Mixed fine corresponds to Dp < 1 um and (sea salt + nss-s o4). Sea salt corresponds to Dp < 1 um and (Na+K+Mg +Ca+Cl+ss-SO4). Mixed/apportioned method (Nov-Dec 1995, 41 deg sout h to 54 south, 135 east to 160 east, for Marine air , long (>= 5days) marine boundary layer residence time )
45c Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to (nss -SO4+NH4+H20). Mixed fine corresponds to Dp < 1 um and (sea salt + nss-s o4). Sea salt corresponds to Dp < 1 um and (Na+K+Mg +Ca+Cl+ss-SO4). Mixed/apportioned method (Nov-Dec 1995, 41 deg sout h to 54 south, 135 east to 160 east, for Perturbed marine air)
45d Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to nss- SO4 ion. Mixed/apportioned method (Nov-Dec 1995, 41 deg sout h to 54 south, 135 east to 160 east, for Marine air , short (<5 days) marine boundary layer residence time)
45e Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to nss- SO4 ion. Mixed/apportioned method (Nov-Dec 1995,41 deg south to 54 south, 135 east to 160 east, for Marine air, long (>= 5days) marine boundary layer residence time)
45f Size distribution and mass data for Dp < 1 um. RH varies between 30-45 %. Sulfate corresponds to nss- SO4 ion. Mixed/apportioned method. (Nov-Dec 1995,41 deg sout h to 54 south, 135 east to 160 east, for Perturbed marine,)
46a Size distributions for Dp < 10 um, RH = 55 %. Sea salt, nss-SO4 ion, dust/trace elements, POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masse s. Reported means for North America, NH marine, dus t, dust/biomass burning, biomass burning. Mixed/apportioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa )
46b Size distributions for Dp < 1.1 um, RH = 55 %. Sea salt includes NO3 and water. Sulfate corresponds t o nss-SO4 ion, with Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to dust or trace eleme nts. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Fine mixed aerosol for Dp < 1.1 u m. Mean for North America. Mixed/apportioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa)
46c Size distributions for Dp < 1.1 um, RH = 55 %. Sea salt includes NO3 and water. Sulfate corresponds t o nss-SO4 ion, with Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to dust or trace eleme nts. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Fine mixed aerosol for Dp < 1.1 u m. Mean for Northern Hemisphere marine. Mixed/apportioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Afr ica)

## Theoretical Method Notes

46d Size distributions for Dp < 1.1 um, RH = 55 %. Sea salt includes NO3 and water. Sulfate corresponds to nss-SO4 ion, with Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to dust or trace eleme nts. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Fine mixed aerosol for Dp < 1.1 u m. Mean for African dust. Mixed/apportioned method. (Jan 14 -Feb 8 1999, Norf olk, VA to Cape Town, South Africa)

46f Size distributions for Dp < 1.1 um, RH = 55 %. Sea salt includes NO3 and water. Sulfate corresponds to nss-SO4 ion, with Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to dust or trace eleme nts. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Fine mixed aerosol for Dp < 1.1 u m. Mean for biomass burning. Mixed/apportioned method (Jan 14 -Feb 8 19 99, Norfolk, VA to Cape Town, South Africa) 46g Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (includes Bs p due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH 4 and water. Mean for North America. Mixed/apportio ned method. (Jan 14 - Feb 8 1999, Norfolk, VA to Cape Town, South Africa)
46h Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (includes Bs p due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH 4 and water. Mean for Northern Hemisphere marine. M ixed/apportioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape To wn, South Africa)
46i Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (includes Bs p due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH 4 and water. Mean for African dust. Mixed/apportion ed method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa) 46j Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (includes Bs p due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH 4 and water. Mean for African dust/biomass burning. Mixed/apportioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape To wn, South Africa)
46k Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (includes Bs p due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH 4 and water. Mean for biomass burning. Mixed/apport ioned method. (Jan 14 - Feb 8 1999, Norfolk, VA to Cape Town, South Africa)
46l Size distributions for 1.1 < Dp < 10 um and RH = 5 5%. Sea salt includes NO3 and water. Dust refers to dust or trace elements. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Mixed coarse ae rosol for 1.1 < Dp < 10 um. Mean for North America. Mixed/apportioned metho d. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa)
46m Size distributions for 1.1 < Dp < 10 um and RH = 5 5%. Sea salt includes NO3 and water. Dust refers to dust or trace elements. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Mixed coarse ae rosol for 1.1 < Dp < 10 um. Mean for Northern Hemisphere marine. Mixed/appo rtioned method. (Jan 14 -Feb 8 1999, Norfolk, VA t o Cape Town, South Africa)
46n Size distributions for 1.1 < Dp < 10 um and RH = 5 5%. Sea salt includes NO3 and water. Dust refers to dust or trace elements. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Mixed coarse ae rosol for 1.1 < Dp < 10 um. Mean for African dust. Mixed/apportioned method . (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, S outh Africa)
46o Size distributions for 1.1 < Dp < 10 um and RH = 5 5%. Sea salt includes NO3 and water. Dust refers to dust or trace elements. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Mixed coarse ae rosol for 1.1 < Dp < 10 um. Mean for African dust/biomass burning. Mixed/ap portioned method. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa) 46p Size distributions for 1.1 < Dp < 10 um and RH = 5 5%. Sea salt includes NO3 and water. Dust refers to dust or trace elements. POM = 1.6* OC for North American air masses and POM = 2.1*OC for all other air masses. Mixed coarse ae rosol for 1.1 < Dp < 10 um. Mean for biomass burning. Mixed/apportioned met hod. (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa)
48a Size distributions for Dp < 10 um and RH = 55 %. S ea salt, nss-SO4 ion, inorganic oxidized material ( dust), POM =1.6*OC. Mean for entire experiment. Mixed/apportioned metho d. (Feb-March 1999, Arabian Sea, Bay of Bengal, Ind ian Ocean, north and south of the ITCZ)
48b Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for SH Atlantic. Mixed/apportioned metho d. (Feb-March 1999)
48c Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for SH Indian Ocean. Mixed/apportioned m ethod. (Feb-March 1999)
48d Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for NH Indian Ocean. Mixed/apportioned m ethod. (Feb-March 1999)
48e Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for East Indian Subcontinent. Mixed/appo rtioned method. (FebMarch 1999)

## Theoretical Method Notes

48f Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for Indian Subcontinent. Mixed/apportion ed method. (Feb-March 1999)

48h Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for Arabia-Indian subcontinent. Mixed/ap portioned method. (FebMarch 1999)
48i Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspon ds to nss-SO4 ion. Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion. Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Fine mixed aerosol corresponds to Dp < 1. 1 um. Mean for Arabian sea, coastal India. Mixed/ap portioned method. (FebMarch 1999) 48j Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for SH Atlantic. Mixed/apportioned method . (Feb-March 1999)
48k Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for SH Indian Ocean. Mixed/apportioned me thod. (Feb-March 1999)
48l Size distributions for Dp < 1.1 um and RH = 55 %. S ulfate corresponds to nss-SO4 aerosol (Bsp due to n ss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for NH Indian Ocean. Mixed/apportioned me thod. (Feb-March 1999)
48m Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for East Indian subcontinent. Mixed/appor tioned method. (FebMarch 1999)
48n Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for Indian subcontinent Mixed/apportioned method. (Feb-March 1999)
48o Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for Arabia Mixed/apportioned method. (Feb -March 1999) 48p Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for Arabia-Indian subcontinent Mixed/appo rtioned method. (FebMarch 1999) 48q Size distributions for Dp < 1.1 um and RH = 55 %. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and wat er). Mean for Arabian Sea, coastal India Mixed/appo rtioned method. (FebMarch 1999)
48r Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for SH Atlantic Mixed/apporti oned method. (FebMarch 1999)
48s Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for SH Indian Ocean Mixed/app ortioned method. (Feb-March 1999)
48t Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for NH Indian Ocean Mixed/app ortioned method. (Feb-March 1999)
48u Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for East Indian Subcontinent Mixed/apportioned method. (Feb-March 1999)
48v Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for Indian Subcontinent Mixed /apportioned method. (Feb-March 1999)
48w Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss-SO4, NH4 and water, and sulfate mass due to nss-SO4 ion). Dust refers to inorganic oxidized material plus residual. POM = 1.6*OC. Mixed coarse aerosol corresponds to 1 .1 < Dp < 10 um. Mean for Arabia Mixed/apportioned method. (Feb-March 1999)

## Theoretical Method Notes

48x Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss- SO4, NH4 and water, and sulfate mass du e to nss-SO4 ion). Dust refers to inorganic oxidize d material plus residual. POM = 1.6*OC. Esp for BC and nss K includes associa ted SO4 and NO3. Mixed coarse aerosol corresponds t o 1.1 < Dp < 10. Mean for Arabia-Indian subcontinent Mixed/apportion ed method. (Feb-March 1999)

48y Size distributions for 1.1 < Dp < 10 um, RH = 55 % . Sea salt includes NO3 and water. Sulfate correspo nds to nss-SO4 ion (Bsp due to nss- SO4, NH4 and water, and sulfate mass du e to nss-SO4 ion). Dust refers to inorganic oxidize d material plus residual. POM = 1.6*OC. Esp for BC and nss K includes associa ted SO4 and NO3. Mixed coarse aerosol corresponds t o 1.1 < Dp < 10. Mean for Arabian sea, coastal India Mixed/apportion ed method. (Feb-March 1999)
48z Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sulfate corresponds to nss-SO4 aerosol (Bsp du e to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and water) Mean for East Indian subcontinent. Mixed/ap portioned method. (FebMarch 1999)
48aa Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sulfate corresponds to nss-SO4 aerosol (Bsp du e to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and water). Mean for Indian subcontinent Mixed/apporti oned method. (Feb-March 1999)
48bb Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sulfate corresponds to nss-SO4 aerosol (Bsp du e to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and water) Mean for Arabia Mixed/apportioned method. ( Feb-March 1999)
48cc Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sulfate corresponds to nss-SO4 aerosol (Bsp du e to nss-SO4 ion, NH4, and water, and sulfate mass due to nss-SO4, NH4 and water). Mean for Arabia-Indian subcontinent Mixed/ apportioned method. (Feb-March 1999)
49a Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for P olluted-Korea/Japan. Mixed/apportioned method. (mi d-March to mid-April 2001)
49b Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere.Esp for EC and nss K, includes ass ociated SO4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for P olluted-Japan. Mixed/apportioned method. (mid-March to mid-April 2001)
49c Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere.Esp for EC and nss K, includes ass ociated SO4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for V olcano+Polluted. Mixed/apportioned method. (mid-Mar ch to mid-April 2001)
49d Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for d ust + Frontal. Mixed/apportioned method. (mid-March to mid-April 2001)
49e Size distributions for Dp < 1.1 um and RH = 55 %. Sea salt includes NO3 and water. Sulfate correspond s to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for D ust + Korea .Mixed/apportioned method. (mid-March t o mid-April 2001)
49f Size distributions for Dp < 1.1 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed fine aerosol for Dp < 1.1 um. Mean for Dust + Shang hai. Mixed/apportioned method. (mid-March to mid-Ap ril 2001) 49g Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, an d sulfate mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions a nd POM = 1.6*OC elsewhere. Esp for EC and nss K, in cludes associated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mean for Polluted-Korea/Japan Mixed/apportioned me thod. (mid-March to mid-April 2001)
49h Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, an d sulfate mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions a nd POM = 1.6*OC elsewhere. Esp for EC and nss K, in cludes associated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mean for Polluted-Japan Mixed/apportioned method. (mid-March to midApril 2001)

## Theoretical Method Notes

49i Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mea n for Volcano+Polluted Mixed/apportioned method. (m id-March to midApril 2001) 49j Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mea n for dust + Frontal.Mixed/apportioned method. (mid -March to mid-April 2001)
49k Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, an d sulfate mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions a nd POM = 1.6*OC elsewhere. Esp for EC and nss K, in cludes associated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mean for Dust + Korea. Mixed/apportioned method. (mid-March to midApril 2001)
49l Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. Sea salt includes NO3 and water. Sulfate corre sponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed coarse aerosol for 1.1 < Dp < 10 um. Mea n for Dust + Shanghai Mixed/apportioned method. (mi d-March to mid-April 2001)
49m Size distributions for Dp < 10 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfat e mass due to nss-SO4, NH4 and water). Dust refers to inorganic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC elsewhere. Esp for EC and nss K, includes as sociated SO4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for P olluted-Korea/Japan. Mixed/apportioned method. (mi d-March to mid-April 2001)
49n Size distributions for Dp < 10 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for Polluted-Ja pan. Mixed/apportioned method. (mid-March to mid-A pril 2001)
49o Size distributions for Dp < 10 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for Volcano+Poll uted. Mixed/apportioned method. (mid-March to mid- April 2001) 49p Size distributions for Dp < 10 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for dust + Front al. Mixed/apportioned method. (mid-March to mid-Ap ril 2001) 49q Size distributions for Dp < 10 um and RH = 55 %. S ea salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for Dust + Korea . Mixed/apportioned method. (mid-March to mid-April 2001)
49r Size distributions for Dp < 10 um and RH = 55 %. Se a salt includes NO3 and water. Sulfate corresponds to nss-SO4 aerosol (Bsp due to nss-SO4 ion, NH4, and water, and sulfate mas s due to nss-SO4, NH4 and water). Dust refers to in organic oxidized material. POM = 2.1*OC in marine regions and POM = 1.6*OC els ewhere. Esp for EC and nss K, includes associated S O4 and NO3. Mixed total aerosol for Dp < 10 um. Mean for Dust + Shang hai. Mixed/apportioned method. (mid-March to mid-Ap ril 2001)

### Table 3 Summary of a literature survey of mass scat tering efficiencies using the measurement method. T he

first column corresponds to the reference number an d entry in the associated notes table.



## Measurement Method Mass Scattering Efficiencies (m 2 

## g - 1 

## )*

Note Fine Mode Coarse Mode Total Sulfate Total Dust** Location/

Characteristics/ Study Time

1 1 1.2±0.9 Baltimore MD Canadian Smoke Jul 4,6,10 2002

2 2 1.84±0.18 Yulin China Polluted periods (ACE-Asia) Apr 2002

2 3 1.03±0.13 Yulin China Dust periods (ACE-Asia) Apr 2002

6 4 3.0±0.6 2.3 Beijing China Jun 1999

7 5 3.9±0.5 Atlanta GA (Supersite) Jul–Sep 1999
8a 1.65 Brisbane Australia Apr-Jun 1999

9a 7.6 Fort Meade MD (MARCH-Atlantic study) Jul 1999

11 6 2.1±0.2 Phoenix AZ Winter 1989- 1990

11 7 1.720±0.014 Meadview AZ (MOHAVE study) Summer 1992

11 8 1.89±0.04 Buffalo Pass CO (Mt. Zirkel Visibility Study) Summer/Fall 1995

11 9 2.2±0.4 Brighton CO (NFRAQS Study) Winter 1997

11 10 2.0±0.5 Welby CO (NFRAQS Study) Winter 1997

11 11 3.45±0.07 Bakersfield CA (IMS95 Study) Winter 1995

11 12 5.1±0.4 Mexico City Mexico Winter 1997

12 13 3.7, 4.1, 5.2 Maldives (INDOEX) (b sp < 25 Mm-1) Feb–Mar 1999

12 14 3.4, 2.2, 3.9,

4.7 Maldives (INDOEX) (25 < b sp < 55 Mm-1) Feb–Mar 1999

12 15 3.5, 2.9, 4.1,

4.4 Maldives (INDOEX) (b sp > 55 Mm-1) Feb–Mar 1999

12 16 3.5, 3.1, 3.8,

4.5 Maldives Bay of Bengal trajectory (INDOEX study) Feb–Mar 1999

12 17 2.7, 3.9, 4.3 Maldives Arabian trajectory (INDOEX study) Feb–Mar 1999

18a 18 2.02 (1.47) Big Bend National Park, TX (BRAVO study) Jul-Oct 1999

21a 4.1 Bondville IL Jan-Dec 1995 23a 0.77 Barbados Apr-May 1994

27a 4.19 Mt. Rainier National Park WA (PREVENT study) Summer 1990

27b 4.26 North Cascades National Park WA (PREVENT study) Summer 1990Note Fine Mode Coarse Mode Total Sulfate Dust Location/ Characteristics/ Study Time

34a 19 3.70±0.14 0.52 Tenerife Canary Islands Jul 1995

35a 20 3.7* Dallas Fort-Worth TX (DFWWHP study) Feb 23, 1995

35b 21 3.1* Dallas Fort-Worth TX (DFWWHP study) Feb 25, 1995

35c 22 3.8* Dallas Fort-Worth TX (DFWWHP study) Dec 30, 1995

42a 6 New England and Mid-Atlantic Smoke aerosol Jul 2002

47h 2.5 Barrow AK 1997-2000

50a 3.67 San Joaquin Valley CA (IMS95 Study) Dec 1995–Jan 1996

54a 23 1.91 Buffalo Pass CO (Mt. Zirkel Visibility Study) Aug, Sep, Oct 1995

56a 23 2.37 0.27 Spirit Mountain NV (SCENES program) Apr-Sep 1989

56c 24 2.53 0.28 Meadview AZ (SCENES program) Apr-Sep 1989

56d 24 2.5 0.54 Meadview AZ (SCENES program) Apr-Sep 1989,

56e 2.4 0.52 Spirit Mountain NV (SCENES program) Apr-Sept1989

57a 4 Linan China Nov 1999

Footnotes for Measurement Method * All values reported for a wavelength of 550 nm un less otherwise stated in the note table. Size range s, relative humidity (when reported) and instruments are stated in the Measure ment note table. Value in parentheses corresponds t o efficiencies converted to dry ammonium sulfate. ** Dust values correspond to total size distributio n.

1 Average and standard deviation of three time period s (see notes 1a, 1b, and 1c). Mass derived from siz e distribution volume concentration and density.
2 Average and standard deviation of three polluted p eriods (see notes 2a, 2b, and 2c)
3 Average and standard deviation of three dust perio ds (see notes 2d, 2e, and 2f in note table)
4 Average and standard deviation of PM1.8 from MOUDI and PM2.5 from filter mass (see notes 6a and 6c) 5 Average and standard deviation of PM2.5 TEOM, PM2. 5 filter and PM1.8 MOUDI estimates (see notes 7a, 7 b and 7c)
6 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11a and 11b).
7 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11c and 11d).
8 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11e and 11f). 9 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11g and 11h).
10 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11i and 11j).
11 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11k and 11l).
12 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11m and 11n).
13 Values correspond to estimates from gravimetric ma ss from Caltech and R/V Ronald Brown and the sum of chemically analyzed mass from R/V Ronald Brown, respectively ( see notes 12a, 12b and 12c).
14 Values correspond to estimates from gravimetric mas s from Caltech, sum of chemically analyzed mass fro m U. of Miami, gravimetric mass from R/V Ronald Brown and the sum of chemically analyzed mass from R/V Ronald Brown, respectively (see notes 12d, 12e, 12f and 12g). 15 Values correspond to estimates from gravimetric ma ss from Caltech, sum of chemically analyzed mass fr om U. of Miami, gravimetric mass from R/V Ronald Brown and the sum of chemically analyzed mass from R/V Ronald Brown, respectively (see notes 12h, 12i, 12j and 12k). 16 Values correspond to estimates from gravimetric ma ss from Caltech, sum of chemically analyzed mass fr om U. of Miami, gravimetric mass from R/V Ronald Brown and the sum of chemically analyzed mass from R/V Ronald Brown, respectively (see notes 12l, 12m, 12n and 12o).17 Values correspond to estimates from sum of chemica lly analyzed mass from U. of Miami, gravimetric mas s from R/V Ronald

Brown and the sum of chemically analyzed mass from R/V Ronald Brown, respectively (see notes 12p, 12q, and 12r).
18 Converting this value to ammonium sulfate mass wou ld be 1.47 m 2 g -1

19 Average and standard deviation of values from a du sty and non-dusty period (see notes 34b and 34c).
20 Ratio of b sp and dry+water mass at RH = 73%.
21 Ratio of b sp and dry+water mass at RH = 44%.
22 

### Ratio of b sp 

### and dry+water mass at RH=71%.
23 Computed by using mass and bsp values reported in the manuscript
24 As reported in the manuscript.



## Measurement Method Notes table with further details about measurement methods Measurement Method Notes

1a Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 μm). Bsp measured with R adiance Research M903 integrating nephelometer at a wavelength at 53 0 nm. RH values not stated. Values are means. (July 4 0100 LT - July 6 1900 LT 2002, Baltimore Supersite. Smoke transport from Canada)
1b Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 μm). Bsp measured with Radiance Research M903 integrating nephelometer at a wavelength at 53 0 nm. RH values not stated. Values are means. July 6 1905 LT - July 10 2200 LT 2002, Baltimore Supersite. Smoke transport from Canada)
1c Mass derived from size distributions from SMPS and APS (0.00931 < Dp < 20.535 μm). Bsp measured with Radiance Research M903 integrating nephelometer at a wavelength at 53 0 nm. RH values not stated. Values are means. (July 10 2205 LT - July 13 0055 LT 2002, Baltimore Supersite. Smoke transport from Canada)
2a Esp derived from slope of TEOM PM9 mass and correc ted Bsp measured with a TSI 3563 nephelometer at a wavelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China, polluted period 3, local origin)
2b Esp derived from slope of TEOM PM9 mass and correc ted Bsp measured with a TSI 3563 nephelometer at a wavelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China polluted period 4, local origin,)
2c Esp derived from slope of TEOM PM9 mass and correc ted Bsp measured with a TSI 3563 nephelometer at a wavelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China, polluted period 5, local origin)
2d Esp derived from slope of TEOM PM9 mass and correc ted Bsp measured with a TSI 3563 nephelometer at a wavelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China, dust period 3, local origin)
2e Esp derived from slope of TEOM PM9 mass and correc ted Bsp measured with a TSI 3563 nephelometer at a wavelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China, dust period 4, transported + local o rigin)
2f Esp derived from slope of TEOM PM9 mass and correct ed Bsp measured with a TSI 3563 nephelometer at a w avelength of 450 nm. RH values not stated. (April, 2002, Zhenbeitai, Yulin, China, dust period 5, local origin)
6a Mixed fine corresponds to mass from MOUDI size dis tributions up to PM1.8 and Bsp measured with a Radi ance Research nephelometer at a wavelength at 530 nm and RH < 40 %. (Jun 11 - Jun 15, 1999, Peking University, Beiji ng, China)
6b Mass from TEOM PM10 and Bsp measured with a Radianc e Research nephelometer at a wavelength at 530 nm a nd RH < 40 %. (Jun 10 22:00 -June 16 11:00 1999, Peking Universit y, Beijing, China)
6c Mass from PM2.5 filter and Bsp measured with a Rad iance Research nephelometer at a wavelength at 530 nm and RH < 40 %. (Jun 10 22:00 -June 16 11:00 1999, Peking Universit y, Beijing, China )
7a TEOM PM2.5 mass and Bsp measured with a Radiance R esearch M903 nephelometer at a wavelength of 530 nm . Average RH value of 48 %. (July 30 - Sept 3 1999, Atlanta, GA)
7b PM2.5 filter mass and Bsp measured with a Radiance Research M903 nephelometer at a wavelength of 530 nm (July 30 - Sept 3 1999, Atlanta)
7c MOUDI mass (includes sum of all stages and after-f ilter, 0.056 < Dp < 1.78 μm). Eap based on measured EC size distribution and measured Bap with a PSAP at a wavelength of 550 nm. (July 30 - Sept 3 1999, Atlanta, GA)
7d R&P 5400 EC data and Bap measured with a PSAP at a wavelength of 550 nm. (July 30 - Sept 3 1999, Atla nta, GA)
8a PM2.5 Esp mass and dry Bsp from a nephelometer at a wavelength of 530 nm for all PM2.5 aerosols. (Apr il-June 1999, Eagle Farm, Brisbane, Australia)
9a PM2.5 mass and Bsp from a Belfort Model 6620 forwa rd scatter visibility meter at a wavelength of 515 nm for hydrated aerosol. Ambient water mass estimated through ISORROPIA. (Ju ly 1999, 2000, Fort Meade, MD)
11a PM2.5 mass and Bsp from MRI model 1550 nephelomete r at a wavelength of 450 nm. Unweighted regression. (Winter 1989- 1990, Phoenix, AZ, 6 hour sampling durations)
11b PM2.5 mass and Bsp from MRI model 1550 nephelomete r at a wavelength of 450 nm. Effective-variance-wei ghted regression. (winter 1989-1990, Phoenix, AZ, 6 hour sampling dur ations)
11c PM2.5 mass and Bsp from MRI model 1560 nephelomete r at a wavelength at 525 nm and RH < 60 %. Unweight ed regression. (Summer 1992, Meadview, AZ, 12 hour samples)
11d PM2.5 mass and Bsp from MRI model 1560 nephelomete r at a wavelength at 525 nm and RH < 60 %. Effectiv e variance weighted regression. (Summer 1992, Meadview, AZ, 12 hour samples)11e PM2.5 mass and Bsp from TSI nephelometer at RH < 6 0 %. Unweighted regression. (Summer/fall 1995, Buff alo pass, CO, 6 hour samples) 

## Measurement Method Notes

11f PM2.5 mass and Bsp from TSI nephelometer at RH < 6 0 %. Effective variance weighted regression. (Summe r/fall 1995, Buffalo pass, CO, 6 hour samples) 11g PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Unweighted regression. (Winter 1997, Brighton, CO,12 hour sampling durations)
11h PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Effective variance weighted reg ression.(Winter 1997, Brighton, CO,12 hour sampling durations)
11i PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Unweighted regression of PM2.5 and Bsp. (Winter 1997, Welby, CO, 12 hour sampling durations) 11j PM2.5 mass and Bsp from ambient-temperature Optec N GN-2 nephelometer. Effective variance weighted regr ession. (Winter 1997, Welby, CO, 12 hour sampling durations)
11k PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Unweighted regression. (Winter 1995, Bakersfield, CA, 3 hour samples)
11l PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Effective variance weighted reg ression. (Winter 1995, Bakersfield, CA,3 hour samples)
11m PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Unweighted regression. (Winter 1997, Mexico City, Mexico, urban site, 6 hour samples)
11n PM2.5 mass and Bsp from ambient-temperature Optec NGN-2 nephelometer. Effective variance weighted reg ression (Winter 1997, Mexico City, Mexico, urban site, 6 hour sampl es)
12a Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Caltech data. Ratio of Bsp and gravimetric mass. (Feb 11 - March 25, 19 99, Kashidhoo Climate Observatory, Maldives, for lo w Bsp regime (Bsp < 25 Mm-1))
12b Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Ratio of Bsp and gravimetric mass. (Feb 11 - March 25, 1999, Kashidhoo Climate Observatory, Mald ives, for low Bsp regime (Bsp < 25 Mm-1))
12c Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Ratio of Bsp and the sum of chemically analyz ed mass. (Feb 11 - March 25, 1999, Kashidhoo Climat e Observatory, Maldives, for low Bsp regime (Bsp < 25 Mm-1))
12d Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Caltech data.Esp is ratio of Bsp and gravimetric mass. (Feb 11 - March 25, 1999, Kashidhoo Climate Observatory, Maldives, medium Bsp regime (25 < Bsp < 55 Mm-1))
12e Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. U. Miami data. Esp is ratio of Bsp and sum of chemically analzyed mass . (Feb 11 - March 25, 1999, Kashidhoo Climate Obser vatory, Maldives, medium Bsp regime (25 < Bsp < 55 Mm-1))
12f Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is ratio of Bsp and gravimetric mass. (Fe b 11 - March 25, 1999, Kashidhoo Climate Observator y, Maldives, medium Bsp regime (25 < Bsp < 55 Mm-1)) 12g Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is ratio of Bsp and sum of chemically ana lyzed mass. (Feb 11 - March 25, 1999, Kashidhoo Cli mate Observatory, Maldives, medium Bsp regime (25 < Bsp < 55 Mm-1))
12h Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Caltech data. Esp is ratio of Bsp and gravimetric mass.(Feb 11 - Marc h 25, 1999, Kashidhoo Climate Observatory, Maldives , high Bsp regime (Bsp > 55 Mm-1))
12i Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. U. Miami data. Esp is ratio of Bsp and sum of chemically analzyed mas s.(Feb 11 - March 25, 1999, Kashidhoo Climate Obser vatory, Maldives, high Bsp regime (Bsp > 55 Mm-1))
12 j Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is ratio of Bsp and gravimetric mass.(Feb 11 - March 25, 1999, Kashidhoo Climate Observatory , Maldives, high Bsp regime (Bsp > 55 Mm-1))
12k Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is ratio of Bsp and chemically analyzed m ass.(Feb 11 - March 25, 1999, Kashidhoo Climate Obs ervatory, Maldives, high Bsp regime (Bsp > 55 Mm-1))
12l Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Caltech data. Esp is ratio of Bsp and gravimetric mass. (Feb 11 - March 25, 1999, Kashidhoo Climate Observatory, Maldives, Bay of Bengal Trajectory)
12m Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. U. of Miami data. Esp is ratio of Bsp and sum of chemically analyzed mass. (Feb 11 - March 25, 1999, Kashidhoo Climate O bservatory, Maldives, Bay of Bengal Trajectory)12n Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V

data. Esp is ratio of Bsp and gravimetric mass. (Fe b 11 - March 25, 1999, Kashidhoo Climate Observator y, Maldives, Bay of Bengal Trajectory) 

## Measurement Method Notes

12o Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is ratio of Bsp and sum of chemically ana lyzed mass. (Feb 11 - March 25, 1999, Kashidhoo Cli mate Observatory, Maldives, Bay of Bengal Trajectory)
12 p Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. U. of Miami data. Esp is the ratio of Bsp and sum of chemically analy zed mass. (Feb 11 - March 25, 1999, Kashidhoo Clima te Observatory, Maldives, Arabian Sea Trajectory) 12q Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is the ratio of Bsp and gravimetric mass. (Feb 11 - March 25, 1999, Kashidhoo Climate Observa tory, Maldives, Arabian Sea Trajectory)
12r Bsp is measured with a TSI 3563 nephelometer at RH = 33 % and Dp < 1 μm. Bap is measured with a PSAP. Ronald Brown R/V data. Esp is the ratio of Bsp and sum of chemically analyzed mass (Feb 11 - March 25, 1999, Kashidhoo Climate Observatory, Maldives, Arabian Sea Trajectory)
18a Computed from SO4 measurements and bsp measurement s with a NGN-2 Optec nephelometer at a wavelength a t 530 nm, for RH < 90 %. Corresponds to RH = 0% from curve fit to Esp as a function of RH, for NH4/SO4 molar ratio o f 1.56 and mass as sulfate ion. (July-Oct 1999, Big Bend National Park , TX)
21a Gravimetric mass for Dp < 1 μm and RH < 40 %, and from bsp measured with an integrating nephelometer (Jan-Dec 1995, Bondville, IL)
23a Bsp measured with Radiance Research M903 nephelomet er at a wavelength of 530 nm, RH < 40% and Dp < 10 μm, corrected for truncation. (April 4 - May 3, 1994, Barbados)
27a PM2.5 mass and Bsp measured with integrating nephe lometers run at near ambient conditions. Esp comput ed JLH. Wavelength not stated. Eap is the ratio of Babs by LIPM and LA C mass. (summer 1990, Tahoma Woods, Mount Rainier N ational Park, WA)
27b PM2.5 mass and Bsp measured with integrating nephe lometers run at near ambient conditions. Esp comput ed JLH. Wavelength not stated. Eap is the ratio of Babs by LIPM and LA C mass. (summer 1990, Marblemount, North Cascades N ational Park, WA)
34a Computed Esp total mass and total Bsp during non-d usty period and assumed the relationship held durin g dusty period. Subtracted non-dust scattering from total Bsp durin g dusty period to get dust scattering. Bsp from a T SI 3563 nephelometer, corrected for truncation. (July 3 - 29 1995, Izana, Tenerife, Canary Islands)
34b Measured SO4 data as ammonium sulfate and Bsp from TSI 3563 nephelometer during non-dusty periods. Bs p attributed to sulfate was determined by subtracting off dust-rela ted Bsp and assuming everything else is sulfate. R H not stated. (July 3 - 29 1999, Izana, Tenerife, Canary Islands)
34c Measured SO4 data as ammonium sulfate and Bsp from TSI 3563 nephelometer during dusty periods. Bsp at tributed to sulfate was determined by subtracting off dust-related Bsp and assuming everything else is sulfate. RH not st ated. (July 3 - 29 1999, Izana, Tenerife, Canary Islands)
35a Mass is estimated from dry size distributions with water from SCAPE. Bsp from ambient RH Optec NGN-2 nephelometer. RH = 73 %. Wavelength not stated (Feb 23 10:00-11:00 199 5, Dallas-Fort Worth. Estimated for 1 hour of data)
35b Mass is estimated from dry size distributions with water from SCAPE. Bsp from Optec NGN-2 nephelomete r. RH = 44 %. Wavelength not stated (Feb 25 10:00-11:00 1995, Dal las-Fort Worth. Estimated for 1 hour of data.)
35c Mass is estimated from dry size distributions with water from SCAPE. Bsp from Optec NGN-2 nephelomete r. RH = 71 %. Wavelength not stated.(Dec 30 10:00-11:00 1994, Dal las-Fort Worth. Estimated for 1 hour of data.)
42a Fine mass and ambient Bsp measured with an Optec N GN3 nephelometer. POM = 1.8*OC. Stated as smoke sca ttering to mass ratio. (July 2002, New England and Mid-Atlantic Sta tes, smoke conditions)
47h RH < 40 %, TSI 3563 nephelometer, Dp < 1 um; absorp tion by PSAP, Dp < 1 um,using multiple linear regre ssion, corresponding to total submicron aerosol, (All year 1997 - 2000, Barrow,AK)
50a Heated Belfort-MRI 1550B nephelometer at a wavelen gth of 475 nm and PM2.5 mass regression for RH < 60 %, (Dec 9 1995 - Jan 6 1996, Bakersfield Van Horn School, San Joaqui n Valley, CA)
54a Linear regression of PM2.5 mass and Bsp with TSI 3 563 nephelometer at a RH of 31 %. (Aug 3 - Sept 2, 1995 and Sept 15 - Oct 15 1995, Buffalo Pass, Mt Zirkel Wilderness Area, C O, average morning (0600-1200 MST) and afternoon (1 200-1800 MST))
56a PM2.5 gravimetric mass and Bsp measured with a MRI 1597 integrating nephelometer at a wavelength of 5 25 nm. Eap is for a ratio of Babs from LIPM and PM2.5 aerosol. Coarse E sp is for 2.5 < Dp < 15 μm gravimetric mass. Ratio computed by JLH. (AprilSept 1989, Spirit Mountain, Nevada)
56b Eap for coarse (2.5 < Dp < 15 μm) gravimetric mass and Babs from LIPM. Ratio computed by JLH. (April- Sept 1989, Spirit Mountain, Nevada
56c PM2.5 gravimetric mass and Bsp measured with a MRI 1597 integrating nephelometer at a wavelength of 5 25 nm. Coarse mode corresponds to 2.5 < Dp < 15 μm gravimetric mass. R atio computed by JLH. (April-Sept 1989, Meadview, A Z)
56d Mean PM2.5 dust + haze mass and Bsp measured with a MRI 1597 integrating nephelometer at a wavelength of 525 nm. Coarse mode corresponds to 2.5 < Dp < 15 μm. (April-Sept 1 989, Meadview, AZ)56e Mean PM2.5 dust + haze mass and Bsp measured with a MRI 1597 integrating nephelometer at a wavelength of 525 nm. Coarse

mode corresponds to 2.5 < Dp < 15 μm (April-Sept 19 89, Spirit Mountain, NV)
57a PM2.5 mass and Bsp measured with Radiance Research nephelometer at 530 nm for RH < 40 %. Bap measured with a PSAP at 565 nm. (Oct 28-Nov 20 1999, Linan, China)

## Table 4 . Summary of a literature survey of mass scattering efficiencies using the multi-linear

regression (MLR) method. The first column corresponds to the refere nce number and entry in the associated notes table. Entries correspond to t he fine mode unless otherwise stated in the column heading, or noted with superscripts.

Multi-Linear Regression Method Mass Scattering Effi ciency (m 2 

## g - 1 

## )*

Notes Fine

Mode Coarse

Mode Sulfate POM Nitrate Dust Sea Salt Location/ Study Time

4 1 5.8 0.5 5.6 4.1 † 0.71 ♦ Sde Boker Israel (ARACHNE study) Dec

1995– Oct 1997

8 2 10.9 2.73 Brisbane Australia Apr-Jun

1999

11 3 2.5±0.6 0.62±0.16 Tucson AZ Winter 1989- 1990

11 4 1.5±0.4 0.8±0.3 Welby CO (NFRAQS study) Summer

1996

11 5 3.0±0.2 0.275±0.007 Welby CO (NFRAQS study) Winter

1996

14 6 0.07 2.08 1.05 0.82 1.77 2.06 Canyonlands National Park UT 1990-

1991

15 7 0.9, 3.11 3.44 Salt Lake City UT Jan-Feb

2001

16 8 3 7.4 3.4 † Sde Boker Israel (ARACHNE study) Jun-Jul

1996

20 3.669 0.121 Sde Boker Israel (ARACHNE study) Feb-Mar

1997

21 9 4.57 4.0 † 4.11 Bondville IL Jan-Dec 1995

25 10 3.2±0.3 3.10±0.10 2.07 ± 0.07 3.47±0.12 0.7±0.6 Meadview AZ (MOHAVE study) Summer

1992

25 11 2.6±0.3 2.28±1.11 1.5±0.7 6.0 ± 1.7 5±2 Meadview AZ (MOHAVE study Winter

1992

25 12 8±3 2.6±0.9 1.7±0.6 2.4 ± 0.9 4±3 Phoenix AZ Winter 1989- 1990

25 13 7.3±0.3 3.05 † 12±8

8±5 1.8±0.9 Uniontown PA Summer

1990

26 5.2 0.34 Sde Boker Israel 1995–

Feb 1997

30 2.2 1.8 1.4 2.2 0.79 Grand Canyon National Park AZ Jul-Aug

1998Notes Fine Mode Coarse

Mode Sulfate POM Nitrate Dust Sea Salt Location/ Study Time

36 6.3 4.6 † 2.9 ‡ Tenerife Canary Islands Jul 1995

39 8.3 6.0 † Rural Great Hungarian Plain Oct

1994– Mar 1995

43 14 4.3 0.6 3.6 2.6 †, ♦ Pacific Ocean and Cheeka Peak WA (PSI91 and MAGE92 Studies) 1991 &

1992

44 15 4.5 ± 0.9 3.2 †, ♦ 4.95 ± 0.07, 0.90 ± 0.3 ‡ Central Pacific Ocean (RITS 93 and RITS 94) 1993 &

1994

46 16 5.7 2.4 †, ♦ 2.7 ♦ 0.9 ♦ 2.2 ♦ Norfolk VA to Cape Town, South Africa, (Aerosols99) Jan-Feb

1999

47 17 0.82 5.3 3.9 † 2.2 Barrow, AK 1997- 2000

48 18 2 0.83 †, ♦ 1.6

1.4 ♦ 0.51 ♦ 1.7 ♦ Indian Ocean (INDOEX) Feb-Mar

1999

50 19 3.00±0.14 3.9±0.3 1.5 † San Joaquin Valley CA (IMS95) Dec

1995– Jan 1996

51 20 5.2±0.3 1.9±0.4 1.8±0.4 Cranmore Mountain NH Apr–

May, 2000

52 6.54 3.36 2.61 Southern New Hampshire Jul

2000- Sep 2001

54 22 5.3±0.3 3.3 † 0.9±0.3

0.7±0.2 6.2±0.4 Mt Zirkel Wilderness Area, CO (MZVS study) Aug-Oct

1995

56a 23 2.4 1.7 2.6, 0.45 ‡ Meadview AZ Apr-Sep

1998

56b 23 2.2 1.9 3.1, 0.34 ‡ Spirit

Mountain NV Apr-Sep

1998

Footnotes for multi-linear regression method table All values reported for a wavelength of 550 nm unle ss otherwise stated in the note table. Values corre spond to fine mode unless otherwise noted in the column header or by f oot note. Size ranges and relative humidity (when r eported) are stated in the MLR note table or in the footnotes. MLR method includes internally mixed and externally mixed meth ods, also found in the MLR note table for each entry.

In the “sulfate” column, values corresponding to dr y ammonium sulfate are italicized. In the “POM” column, values we normalized to POM mu ltiplier of 1.8 are italicized

† We converted to dry ammonium sulfate‡ Corresponds to coarse mode (supermicron)

♦ Corresponds to total modes (supramicron, fine + co arse)

1 Two separate MLR runs were performed, one with fin e mass (Dp < 2 μm) and coarse mass (2-10 μm). The s econd was with total dust (Dp < 10 μm) and fine sulfate ion (Dp < 2 μm).
2 Sulfate is PM2.5 ammonium sulfate, soil is PM2.5.
3 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11a and 11b). Coarse refers to PM10 – PM2.5.
4 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11c and 11d). Coarse refers to PM10 – PM2.5. 5 Average and standard deviation of unweighted and e ffective-variance weighted estimates (see notes 11e and 11f). Coarse refers to PM10 – PM2.5.
6 Reporting annual values only. Dust corresponds to PM2.5 mode.
7 Organic carbon values are for non-volatile organic s and semi-volatile organics, respectively (see not es 15a and 15b).
8 Fine mixed refers to fine mass – nss-SO4 ion. Sulf ate is sulfate ion 9 Organic carbon value refers to carbon-containing a erosols
10 Average and standard deviation of effective varian ce weighting with and without intercepts, and no we ighting (see notes 25a, 25b, and 25c) for PM2.5.
11 Average and standard deviation of effective varian ce weighting with and without intercepts, no weight ing, and average absolute difference < 20 % effective variance weigh ting (see notes 25d, 25e, 25f, and 25g) for PM2.5.
12 Average and standard deviation of effective varian ce weighting with and without intercepts, no weight ing, and average absolute difference < 20 % effective variance weigh ting (see notes 25h, 25i, 25j, and 25k) for PM2.5.
13 Average and standard deviation of effective varian ce weighting with and without intercepts, and no we ighting (see notes 25l, 25m, and 25n) for PM2.5.
14 Sulfate corresponds to sulfate ion for Dp < 10 μm. Fine mixed is residual mass for Dp < 1 μm and coar se mixed is for residual mass for 1 < Dp < 10 μm. 15 Average and standard deviation for RITS93 and RITS 94 (see notes 44a and 44c). Sulfate is nss-SO4 ion for Dp < 10 μm. Sea salt is listed for Dp < 1 μm and 1 < Dp < 10 μm, re spectively. 16 Sulfate ion, all values are for Dp < 10 μm.
17 Sulfate ion and sea salt for Dp < 1 μm
18 Sulfate ion and other values for Dp < 10 μm 19 Fine sulfate corresponds to ammonium salts (SO4+NO 3+NH4). Mixed fine is everything besides salts. Ave rage and standard deviation for OC back up filter added back and subt racted, respectively (see notes 50a and 50b)
20 Sulfate is ammonium sulfate. Average and standard deviation of N/NE and W/SW air masses (notes 51a an d 51b)
21 Sulfate is ammonium sulfate
22 Sulfate is ammonium sulfate and nitrate is ammoniu m nitrate. Average and standard deviation for uncor rected OC, OC corrected for positive organic artifact, and correc ted for negative organic artifact, respectively. (O C numbers are for uncorrected and negative artifact correction only). See notes 5 4a, 54b and 54c.
23 Mixed fine is PM2.5 haze. Mixed coarse is 2.5 < Dp < 15 μm haze. Dust is for fine and coarse mode, re spectively.



## Multi-Linear Regression Method Notes table with fur ther details about measurement methods

Multi Linear Regression (MLR) Method Notes

4 Mass from SFU samplers and total Bsp measured with a TSI 3563 nephelometer, corrected for non-Lambert ian and truncation errors. Average instrument RH was 38 %. MLR perform ed twice: once with fine particle mass (Dp < 2 μm) and coarse particle mass (2 < Dp < 10 μm). The second MLR was performed with dust (Dp < 10 μm) and sulfur converted to sulfate ion (Dp < 2 μm). Internal and external mixture methods. (Dec 1995 - Oct 1997, Sde Boker, Negev desert, Israel)
8 PM2.5 Esp mass and dry Bsp from a nephelometer at a wavelength of 530 nm for all PM2.5 aerosols, PM2. 5 soil, and PM2.5 ammonium sulfate. External mixture method. (April-J une 1999, Eagle Farm, Brisbane, Australia)
11a PM2.5 mass and Bsp from MRI model 1592 nephelomete r at a wavelength at 530 nm. Coarse mode is PM10 – PM2.5. Internal mixture method. Unweighted regression. (Winter 1989 -1990, Tucson, AZ,6 hour sampling durations)
11b PM2.5 mass and Bsp from MRI model 1592 nephelomete r at a wavelength at 530 nm. Effective variance wei ghted regression. Coarse mode is PM10 – PM2.5. Internal mixture metho d. (Winter 1989-1990, Tucson, AZ, 6 hour sampling d urations)
11c PM2.5 mass and Bsp from an ambient-temperature Opte c NGN-2 nephelometer. Coarse mode is PM10 – PM2.5. Unweighted regression. Internal mixture method. (Summer 1996, Welby, CO,12 hour sampling durations)
11d PM2.5 mass and Bsp from an ambient-temperature Opt ec NGN-2 nephelometer. Coarse mode is PM10 – PM2.5. Effective variance weighted regression. Internal mixture meth od. (Summer 1996, Welby, CO,12 hour sampling durati ons)
11e PM2.5 mass and Bsp from an ambient-temperature Opt ec NGN-2 nephelometer. Coarse mode is PM10 – PM2.5. Unweighted regression. Internal mixture method. (Welby, CO, wi nter 1996,12 hour sampling durations)

## Multi Linear Regression (MLR) Method Notes

11f PM2.5 mass and Bsp from an ambient-temperature Opte c NGN-2 nephelometer. Coarse mode is PM10 – PM2.5. Effective variance weighted regression. Internal mixture meth od. (Welby, CO, winter 1996,12 hour sampling durati ons)
14 Bext with Optec LPV-2 transmissometer. MLR with be xt and organic material from BOSS, sulfate as ammon ium sulfate, nitrate as ammonium nitrate, corrected for RH using Tang’s curves, Dust as fine crustal material, assuming cru stal is Fe and Si. Externally mixed method. (1990-1991, Canyonlands National Park , UT)
15a Bsp measured with OPTEC NGN-2 integrating nephelom eter at a wavelength of 530 nm. Nitrate as ammonium nitrate. Organic carbon for non-volatile organic material, using a 1 .64 multiplier. Externally mixed method. (Jan 30 - Feb 4 2001, Salt Lake City, UT)
15b Bsp measured with OPTEC NGN-2 integrating nephelom eter at a wavelength of 530 nm. Organic carbon as s emi-volatile organic material. Externally mixed method. (Jan 30 - Feb 4 2001, Salt Lake City, UT)
16 Bsp by TSI 3563 nephelometer for RH < 50 %. Mixed fine mass is residual fine mass (PMfine - nss-SO4). Sulfate as nss-SO4. Internally mixed method. (June 20 - July 10 1996, S de Boker, Negev Desert, Israel)
20 Fine mass (Dp < 2 μm) and Bsp from TSI 3563 integr ating nephelometer at 50 % RH. Coarse mode is 2 < D p < 10 μm. Internally mixed method (Feb 18 - March 15 1997, Sde Boker, Ne gev Desert, Israel)
21 Mass for Dp < 1 μm and RH < 40 % and Bsp from a MR I 1560 integrating nephelometer. Sulfate correspond s to ammonium bisulfate. Mixed fine mass corresponds to residual mass for Dp < 1 μm (portion of gravimetric mass not identified by IC). (Jan-Dec 1995, Bondville, IL)
25a Bsp estimated with ELSIE. Nitrate as ammonium nitra te. Sulfate as ammonium sulfate. POM = 1.2*OC. Dust as residual mass. Effective variance weighting, no intercept. Externa lly mixed method. Wavelength not stated. RH = 26.1 %. (summer 1992, Meadview, AZ)
25b Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. Effective variance weighting, with intercept. Exter nally mixed method. Wavelength not stated. RH = 26. 1 %. (Summer 1992, Meadview, AZ)
25c Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. No weighting. Wavelength not stated. Externally mix ed method. RH = 26.1 %. (Summer 1992, Meadview, AZ)
25d Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. Effective variance weighting, no intercept. Externa lly mixed method. Wavelength not stated. RH = 45.1 %. (Winter 1992, Meadview, AZ)
25e Bsp estimated with ELSIE. Nitrate as ammonium nitra te. Sulfate as ammonium sulfate. POM = 1.2*OC. Dust as residual mass. Effective variance weighting, with intercept. Exter nally mixed method. Wavelength not stated. RH = 45. 1 %. (Winter 1992, Meadview, AZ)
25f Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. No weighting. Wavelength not stated. Externally mix ed method. RH = 45.1 %. (winter 1992, Meadview, AZ) 25g Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. Absolute average difference < 20 % effective varian ce weighting. Externally mixed method. RH = 45.1 %. Wavelength not stated. (Winter 1992, Meadview, AZ)
25h Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. Effective variance weighting, no intercept. Wavelen gth not stated. Externally mixed method. RH = 31.8 %. (Winter 1989-1990, Phoenix, AZ)
25i Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. Effective variance weighting, with intercept. Wavel ength not stated. Externally mixed method. RH = 31. 8 %. (Winter 1989-1990, Phoenix, AZ) 25j Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium sulfate. POM = 1.2*OC. Dus t as residual mass. No weighting. Wavelength not stated. Externally mix ed method. RH = 31.8 %. (Winter 1989-1990, Phoenix , AZ)
25k Bsp estimated with ELSIE. Nitrate as ammonium nitra te. Sulfate as ammonium sulfate. POM = 1.2*OC. Dust as residual mass. Absolute average difference < 20 % effective varian ce weighting. Wavelength not stated. Externally mix ed method. RH = 31.8 %. (Winter 1989-1990, Phoenix, AZ)
25l Bsp estimated with ELSIE. Nitrate as ammonium nitra te. Sulfate as ammonium bisulfate. POM = 1.2*OC. Du st as residual mass. Effective variance weighting, no intercept. Wavelen gth not stated. Externally mixed method. RH = 66.7 %. (Summer 1990, Uniontown, PA)
25m Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium bisulfate. POM = 1.2*OC. D ust as residual mass. Effective variance weighting, with intercept. Wavelength not stated. Externally mixed method. RH = 66.7 %. (Summer 1990, Uniontown, PA)
25n Bsp estimated with ELSIE. Nitrate as ammonium nitr ate. Sulfate as ammonium bisulfate. POM = 1.2*OC. D ust as residual mass. No weighting. Wavelength not stated. Externally mix ed method. RH = 66.7 %. (Summer 1990, Uniontown, PA )
26 Bsp measured with a TSI 3563 integrating nephelome ter and mass for fine mode (Dp < 2 μm) for coarse m ode (2< Dp < 10 μm). RH not stated. Internally mixed method. (1995-mid F eb 1997,Sde Boker, Negev Desert, Israel)
30 Dry ammonium sulfate mass and Bsp for dry from Rad iance Research M903 nephelometer at a wavelength of 530 nm. POM = 1.4*OC. Nitrate is ammonium nitrate. Soil is PM2.5. Externally mixed method. (July-Aug 1998, Grand Can yon National Park, AZ)

## Multi Linear Regression (MLR) Method Notes

36 Bsp from Radiance research nephelometer at a wavel ength of 530 nm. Sulfate corresponds to nss-sulfate for average RH = 45 % and Dp < 1 μm. Sea salt corresponds to sodium ion f or average RH = 45 % and 1 < Dp < 10 μm. Externally mixed method. (July 1995, Tenerife)
39 Bsp with MRI 1550 nephelometer for Dp < 1 μm and R H = 30 %. Sulfate as ion. Externally mixed method. (Oct 1994 - March 1995, rural Great Hungarian Plain)
43 Bsp measured with an integrating nephelometer at R H = 30 % and Dp < 10 μm. Sulfate corresponds to sul fate ion. Mixed fine corresponds to submicron residual mass. Mixed coars e corresponds to supermicron residual mass. Interna lly mixed method. (1991 & 1992, Pacific Ocean from 33 N to 12 S along 140 W, Cheeka Peak, WA, for PSI and MAGE samples)
44a Bsp was calculated from DMA and APS size distribut ion measurements at RH = 30 %. Sulfate corresponds to sulfate ion. Sea salt is submicron. Externally mixed method. (March- May 1993, 70 deg south to 55 north along 140 W, RIT S 93)
44b Bsp was calculated from DMA and APS size distribut ion measurements at RH = 30 %. Sea salt is supermic ron. Externally mixed method. (March-May 1993, 70 deg south to 55 north a long 140 W, RITS 93)
44c Bsp was calculated from DMA and APS size distribut ion measurements at RH = 30 %. Sulfate corresponds to sulfate ion. Sea salt is submicron. Externally mixed method. (Nov 19 93 - Jan 1994, 70 deg south to 55 north along 140 W , RITS 94)
44d Bsp was calculated from DMA and APS size distribut ion measurements at RH = 30 %. Sea salt is supermic ron. Externally mixed method (Nov 1993 - Jan 1994, 70 deg south to 55 nor th along 140 W, RITS 94)
46a Bsp measured with a TSI 3563 integrating nephelome ter at RH = 55 % and for Dp < 10 μm. Sulfate corres ponds to nss-SO4 ion. POM = 1.6*OC for North American air masses and 2.1* OC for all other air masses. Externally mixed metho d. Mean values for North America, NH marine, dust, dust/biomass burnin g, biomass burning. (Jan 14-Feb 8, 1999, Norfolk, V A to Cape Town, South Africa)
47d Bsp measured with a TSI 3563 nephelometer for Dp < 1 μm and RH < 40 %. Sulfate corresponds to SO4 ion. Mixed fine aerosol corresponds to residual mass. Externally mixed meth od. (All year 1997 - 2000, Barrow,AK)
48a Bsp measured with TSI 3563 integrating nephelomete r at RH = 55 % for Dp < 10 μm. Sulfate corresponds to nss-SO4 ion. POM = 1.6*OC. Dust refers to inorganic oxidized materia l. Mean for the entire experiment. Externally mixed method. (Feb-Mar 1999, Arabian Sea, Bay of Bengal, Indian Ocean -north and south of the ITCZ)
50a Heated Belfort-MRI 1550B nephelometer at a wavelen gth of 475 nm and RH < 60 %. Mixed fine aerosol cor responds to salts (SO4+NH4+NO3). OC back up filter added. Internally mixed method. (Dec 9 1995 - Jan 6 1996, Bakersfield Van Horn School, San Joaquin Valley, CA)
50b Heated Belfort-MRI 1550B nephelometer at a wavelen gth of 475 nm and RH < 60 %. Mixed fine corresponds to all other species besides salts. OC back up filter was added back. In ternally mixed method. (Dec 9 1995 - Jan 6 1996, Ba kersfield Van Horn School, San Joaquin Valley, CA)
50c Heated Belfort-MRI 1550B nephelometer at a wavelen gth of 475 nm and RH < 60 %. Mixed fine aerosol cor responds to salts (SO4+NH4+NO3). OC back up filter was subtracted. In ternally mixed method. (Dec 9 1995 - Jan 6 1996, Ba kersfield Van Horn School, San Joaquin Valley, CA)
50d Heated Belfort-MRI 1550B nephelometer at a wavelen gth of 475 nm and RH < 60 %. Mixed fine aerosol cor responds to all other species besides salts. OC back up filter was subtra cted. Internally mixed method. (Dec 9 1995 - Jan 6 1996, Bakersfield Van Horn School, San Joaquin Valley, CA)
51a Bsp measured with Radiance Research M903 nephelome ter at 530 nm at ambient RH (< 50 % typically). Sul fate corresponds to ammonium sulfate. POM = 1.7*OC. OC from TOT. Extern ally mixed method. (April 18 - May 13, 2000, Cranmo re Mountain, New Hampshire, for north/northeast air masses,)
51b Bsp measured with Radiance Research M903 nephelome ter at 530 nm at ambient RH (<50 % typically). Sulf ate corresponds to ammonium sulfate. POM = 1.7*OC. OC from TOT. Extern ally mixed method. (April 18 - May 13, 2000, Cranmo re Mountain, New Hampshire, for west/southwest air masses)
52 Bsp from Radiance Research M903 nephelometer at a wavelength of 530 nm. Sulfate corresponds to ammoni um sulfate. POM =1.4*OC from TOT method. Values correspond to all m easurements. Externally mixed method. (July 2000-Se pt 2001, rural site in southern New Hampshire)
54a PM2.5 mass and Bsp with TSI 3563 nephelometer for RH < 52 %. Sulfate corresponds to ammonium sulfate. POM = 1.4*OC). Nitrate corresponds to ammonium nitrate. Uncorrecte d OC. Externally mixed method. (Aug 3 - Sept 2, 199 5 and Sept 15 - Oct 15 1995, Buffalo Pass, Mt Zirkel Wilderness Area, CO)
54b PM2.5 mass and Bsp with TSI 3563 nephelometer for RH < 52 %. Sulfate corresponds to ammonium sulfate. POM = 1.4*OC). Nitrate corresponds to ammonium nitrate. OC correct ed for positive organic artifact. Externally mixed method. (Aug 3 - Sept 2, 1995 and Sept 15 - Oct 15 1995, Buffalo Pass, Mt Zi rkel Wilderness Area, CO)
54c PM2.5 mass and Bsp with TSI 3563 nephelometer for RH < 52 %. Sulfate corresponds to ammonium sulfate. POM = 1.4*OC). Nitrate corresponds to ammonium nitrate. OC correct ed for negative organic artifact. Externally mixed method. (Aug 3 - Sept 2, 1995 and Sept 15 - Oct 15 1995, Buffalo Pass, Mt Zi rkel Wilderness Area, CO)
56a PM2.5 mass and Bsp measured with a MRI 1597 integr ating nephelometers at wavelength of 525nm. Mixed f ine corresponds to haze. Dust corresponds to PM2.5. Coarse mode aeroso l corresponds to 2.5 < Dp < 15 μm, both for haze a nd dust. Internally mixed method. (April-Sept 1998, Meadview, AZ)

## Multi Linear Regression (MLR) Method Notes

56b PM2.5 mass and Bsp measured with a MRI 1597 integra ting nephelometers at wavelength of 525nm. Mixed fi ne corresponds to haze. Dust corresponds to PM2.5. Coarse mode aeroso l corresponds to 2.5 < Dp < 15 μm, both for haze a nd dust. Internally mixed method. (April-Sept 1998, Spirit Mountain, NV)

## Table 5. Summary of a literature survey of mass scattering efficiencies using the partial

scattering method. The first column corresponds to the reference numb er and entry in the associated notes table. Entries correspond to the f ine mode.

Partial Scattering Method Mass Scattering Efficienc y (m 2 g -1 ) *

Notes Fine

Mode Sulfate POM Nitrate Dust Location (Study) Time

25a 1 3.5 4.8 3.2 3.8 2.4 Meadview AZ (MOHAVE) Summer 1992,

25b 2 2.7 3.6 2.4 3.3 2.3 Meadview AZ (MOHAVE) Summer 1992,

25c 1 4 5 3.3 4.1 2.1 Meadview AZ (MOHAVE) Winter 1992,

25d 2 3.1 4 2.7 3.7 2.4 Meadview AZ (MOHAVE) Winter 1992,

25e 1 2.7 3.6 2.4 3.8 2 Phoenix AZ Winter 1989-1990

25f 2 2.2 3 2 3.1 2.1 Phoenix AZ Winter 1989-1990, 25g 1 6.9

2.9 † 8.5

5.7 1.8 4.3 Uniontown PA Summer 1990

25h 2 7

2.9 † 8.8

5.9 3.7 4.2 Uniontown PA Summer 1990

41a 3 1.23 3.81 2.5 Bondville IL May-Dec 1994

41b 4 5.78 6.9 4.6 Bondville IL May-Dec 1994

53a 5 4.5 7.1

3.4 † 5.6

3.11 6.6 Denver CO Jan 5 1998

53b 6 2.3 2.1 4.0 2.2 2.3 Denver CO Jan 13 1998

54a 7 2.47 3.61 2.8 2.63 1.76 Mt Zirkel Wilderness Area CO (MZVS) Aug, Sep

Oct 1995

58a 16

2.7 † 6.7

5.2 Hopi Point, Grand Canyon National Park AZ (NGSVS) Jan 18, 1990

58b 6.3

3.2 † 5.3

4.12 Hopi Point, Grand Canyon National Park AZ (NGSVS) Jan 20, 1990

58c 4.6 4.5 3.5 Hopi Point, Grand Canyon National Park AZ (NGSVS) Jan 21, 1990

58d 3.4 5.7 4.4 Hopi Point, Grand Canyon National Park AZ (NGSVS) Jan 22, 1990

58e 5.6

2.4 † 6.3

4.9 Hopi Point, Grand Canyon National Park AZ) (NGSVS) Jan 30, 1990

58f 3.5

2.0 † 8.1

6.3 Hopi Point, Grand Canyon National Park AZ (NGSVS) Feb 12, 1990

58g 8

2.7 † 5.6

4.9 Hopi Point, Grand Canyon National Park, AZ (NGSVS) Feb 13, 1990

58h 15.4

2.2 † 6.7

5.2 Hopi Point, Grand Canyon National Park AZ (NGSVS) Feb 19, 1990Notes Fine Mode Sulfate POM Nitrate Dust Location (Study) Time

58i 5.6

3.2 † 5.6

4.4 Hopi Point, Grand Canyon National Park AZ (NGSVS) Feb 28, 1990

58j 3

1.9 † 7

5.4 Hopi Point, Grand Canyon National Park AZ (NGSVS) Mar 1, 1990

58k 5.4

2.6 † 4.2

3.3 Hopi Point, Grand Canyon National Park AZ (NGSVS) Mar 2, 1990

58l 5.4

2.7 † 5.1

4.0 Hopi Point, Grand Canyon National Park AZ (NGSVS) Mar 3, 1990

58m 5.2

1.93 † 1.3

1.01 Hopi Point, Grand Canyon National Park AZ (NGSVS) Mar 4, 1990

Footnotes for partial scattering method table

*All values for a wavelength of 550 nm unless other wise stated in the Notes table. Values in parenthes es are reported as dry ammonium sulfate efficiencies in the literat ure. See notes table for the original form of sulfa te and the relative humidity of the measurements.

In the “sulfate” column, values corresponding to dr y ammonium sulfate are italicized. In the “POM” column, values we normalized to POM mu ltiplier of 1.8 are italicized Estimates in bold correspond to constant-size scena rio.

† We converted to dry ammonium sulfate

1 Core/shell scenario with constant particle number. Values correspond to PM 2.5 . 2 Homogeneous composition with constant particle siz e. Values correspond to PM 2.5 . 3 Corresponds to PM2.5 aerosols at low RH (30-63 %), core/shell scenario used.
4 Corresponds to PM2.5 aerosols high RH (> 75 %), co re/shell scenario used. 5 Corresponds to RH = 74 %. Interactive efficiency ( conserves particle number).
6 Corresponds to RH = 38 %. Interactive efficiency ( conserves particle number).
7 Constanct composition as a function of size assume d



## Partial Scattering Method Notes table with further details about measurement methods Partial Method Notes

25a Esp estimated with ELSIE and MOUDI size distributi ons, assuming core/shell scenario with constant par ticle number. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 2 6.1 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Summer 1992, Meadview, AZ)
25b Esp estimated with ELSIE and MOUDI size distributi ons, assuming homogeneous composition and constant particle size. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 2 6.1 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Summer 1992, Meadview, AZ)
25c Esp estimated with ELSIE and MOUDI size distributi ons, assuming core/shell scenario with constant par ticle number. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 4 5.1%. Wavelength ~ 530 nm. Results correspond to PM 2.5 (Winter 1992, Meadview, AZ)

## Partial Method Notes

25d Esp estimated with ELSIE and MOUDI size distributio ns, assuming homogeneous composition and constant p article size. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 4 5.1 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Winter 1992, Meadview, AZ)
25e Esp estimated with ELSIE and MOUDI size distributi ons, assuming core/shell scenario with constant par ticle number. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 3 1.8 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Winter 1989- 1990, Phoenix, AZ)
25f Esp estimated with ELSIE and MOUDI size distributi ons, assuming homogeneous composition and constant particle size. Sulfate corresponds to ammonium sulfate. Nitrate correspond s to ammonium nitrate. POM =1.2*OC. Dust correspond s to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 3 1.8 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Winter 1989- 1990, Phoenix, AZ) 25g Esp estimated with ELSIE and MOUDI size distributi ons,assuming core/shell with constant particle numb er. Sulfate corresponds to ammonium bisulfate. Nitrate corresponds to ammon ium nitrate. POM =1.2*OC. Dust corresponds to resid ual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 66.7 %. Wavele ngth ~ 530 nm. Results correspond to PM2.5 (Summer 1990, Uniontown, PA)
25h Esp estimated with ELSIE and MOUDI size distributi ons, assuming homogeneous composition and constant particle size. Sulfate corresponds to ammonium bisulfate. Nitrate correspo nds to ammonium nitrate. POM =1.2*OC. Dust correspo nds to residual mass. Dust is 20 % soluble and OC is 60 % soluble. RH = 6 6.7 %. Wavelength ~ 530 nm. Results correspond to P M2.5 (Summer 1990, Uniontown, PA)
41a MOUDI size distributions, computed for PM2.5 ammon ium sulfate for low RH (30- 63 %), POM (=1.2*OC) as suming OC is 60 % soluble using ELSIE. Core/shell scenario assumed. (May-Dec 1994, Bondville, IL)
41b MOUDI size distributions, computed for PM2.5 ammon ium sulfate for high RH (RH > 75 %), POM (=1.2*OC) assuming OC 60 % is soluble using ELSIE. Core/shell scenario assum ed. (May-Dec 1994, Bondville, IL)
53a MOUDI size distribution (0.03 < Dp < 3.16 um) and ELSIE calculations. Water soluble organic mass take n to be 25% of total carbon. Sulfate corresponds to ammonium sulfate mas s. Nitrate form not stated. POM multiplier not stat ed. RH = 74 %. Wavelength not stated. Interactive efficiency. (Jan 5 1988, De nver, CO, northeasterly flow)
53b MOUDI size distribution (0.03 < Dp < 3.16 um) and ELSIE calculations. Water soluble organic mass take n to be 25% of total carbon. Sulfate corresponds to ammonium sulfate mas s. Nitrate form not stated. POM multiplier not stat ed. RH = 38 %. Wavelength not stated. Interactive efficiency. (Jan 13 1988, D enver, CO, stagnant air mass)
54a Results from ELSIE for ammonium sulfate or bisulfa te, ammonium nitrate, POM (=1.4*OC) and dust. Size distributions inverted from Bsp measurements from a TSI nephelometer. Cons tant composition as a function of size. (Aug 3 - Se pt 2, 1995 and Sept 15 - Oct 15 1995, Buffalo Pass, Mt Zirkel Wilderness Are a, CO)
58a Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 92.2 %, and at a wavelength of 525 nm. NGS study. (Jan 18, 1990, Hopi Point, Grand Canyon National Park, AZ)
58b Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 63.3 %, and at a wavelength of 525 nm. NGS study. (Jan 20, 1990, Hopi Point, Grand Canyon National Park, AZ)
58c Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 44.8 %, and at a wavelength of 525 nm. NGS study. (Jan 21, 1990, Hopi Point, Grand Canyon National Park, AZ)
58d Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 32.9 %, and at a wavelength of 525 nm. NGS study. (Jan 22, 1990, Hopi Point, Grand Canyon National Park, AZ).
58e Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 72.2 %, and at a wavelength of 525 nm. NGS study. (Jan 30, 1990, Hopi Point, Grand Canyon National Park, AZ)
58f Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 53.6 % and at a wavelength of 525 nm. NGS study. (Feb 12, 1990, Hopi Point, Grand Canyon National Park, AZ) 58g Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 81.8 %, and at a wavelength of 525 nm. NGS study. (Feb 13, 1990, Hopi Point, Grand Canyon National Park, AZ),
58h Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions at RH = 92.6 %, and at a wavelength of 525 nm. NGS study. (Feb 19, 1990, Hopi Point, Grand Canyon National Park, AZ)

## Partial Method Notes

58i Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions, RH = 55.2 %, and at a wavelength of 525 nm. NGS study. ( Feb 28, 1990, Hopi Point, Grand Canyon National Park, AZ) 58j Esp calculated for ammonium sulfates and water (per gram of ammonium sulfate), carbonaceous aerosol (P OM =1.4*OC) using composite model and MOUDI size distributions, RH = 48.0 %, and at a wavelength of 525 nm. NGS study. ( Mar 1, 1990, Hopi Point, Grand Canyon National Park, AZ)
58k , Esp calculated for ammonium sulfates and water (p er gram of ammonium sulfate), carbonaceous aerosol (POM =1.4*OC) using composite model and MOUDI size distributions, RH = 67.9 %, and at a wavelength of 525 nm. NGS study. ( Mar 2, 1990, Hopi Point, Grand Canyon National Park, AZ)
58l Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions, RH = 63.5 %, and at a wavelength of 525 nm. NGS study. ( Mar 3, 1990, Hopi Point, Grand Canyon National Park, AZ)
58m Esp calculated for ammonium sulfates and water (pe r gram of ammonium sulfate), carbonaceous aerosol ( POM =1.4*OC) using composite model and MOUDI size distributions, RH = 76.5 %, and at a wavelength of 525 nm. NGS study. ( Mar 4, 1990, Hopi Point, Grand Canyon National Park, AZ)

## Table 7. Summary of mass absorption and scattering efficien cies ( α ap 

## ) of light absorbing carbon

(LAC) and other species. The first column correspon ds to the reference number and entry in the associated notes table. The method table refers to the type of method used to compute α ap 

## (see footnotes).

Mass Absorption Efficiency and LAC Scattering Effic iency (m 2 

## g - 1 

## ) *

Note Method α sp (LAC) Specific

α ap (fine mode) Specific α ap (coarse mode) α ap (LAC) α

ap (Soil) α

ap (POM) Location/Study Time

5 M-1 8.1 (13) Big Bend National Park TX (BRAVO) Sep-Oct

1999

7 1 M-1 18.3, 9.3, 5.3 Atlanta GA (Supersite) Jul-Sep

1999

8 2 MLR1&2 3.89 1.52 0.22 9.08 (10.5), 0.32 0.17 1.11 Brisbane Australia Apr-Jun 1999

12 3 M-1 20, 12 Maldives (INDOEX) (b sp < 25 Mm -1 ) Feb–

Mar 1999

12 4 M-1 13, 17 Maldives (INDOEX) (25 < b sp < 55 Mm -1 Feb–

Mar 1999

12 5 M-1 14, 10 Maldives (INDOEX) (b sp > 55 Mm -1 ) Feb–

Mar 1999

12 6 M-1 16, 12 Maldives Bay of Bengal trajectory (INDOEX study) Feb–

Mar 1999

12 7 M-1 16 Maldives Arabian trajectory (INDOEX study) Feb–

Mar 1999

13a T-2 7.3 Bondville IL Jun-Sep 1997

13b T-2 6 Bondville IL Jun-Sep 1997

13c T-2 3.6 Bondville IL Jun-Sep 1997

13d T-2 5.1 Bondville IL Jun-Sep 1997

13e T-2 4.7 Bondville IL Jun-Sep 1997

13f T-2 1.7 Bondville IL Jun-Sep 1997

16 MLR1&2 8.9 Sde Boker Israel (ARACHNE study) Jun-Jul

1996

19 8 T-2 6.5 ± 0.2 Santa Maria Azores Jun

1992
24a 9 M-1 12 ( 19.2 ) Grenoble France

24b 9 M-1 12 ( 19.2 ) Paris France

24c 9 M-1 20 ( 32 ) Savannah areas, Ivory Coast and Congo

24d 9 M-1 18 ( 28.8 ) Western MediterraneanNote Method α sp (LAC) Specific

α ap (fine mode) Specific α ap (coarse mode) α ap (LAC) α

ap (Soil) α

ap (POM) Location/Study Time

24e 9 M-1 5 ( 8 ) Remote Areas northern tropical Pacific, Mace Head, Ireland; Greenland
27a M-1 14.22 ( 16.4 ) Mount Rainier National Park WA Summer

1990
27b M-1 16.9 ( 19.5 ) North Cascades National Park WA Summer

1990

28a 10 MLR1&2 12.5 ( 14.4 ) 1.8 3.3 Meadview AZ Summer 1992

28b 11 MLR1&2 11.7 ( 13.5 ) 3.7 7.9 Meadview AZ Summer 1992
38 T-1 0.37 12.9 ( 12.4 ) Yosemite National Park (YACS) Jul-Sep

2002

40a 12 M-1 3.58 ( 4.5 ) Brighton, CO (NFRAQS) Jan 1997

40b 13 M-1 8±4 ( 10 ± 5 ) Brighton CO (NFRAQS) Dec

1996, Jan 1997

46a MLR-2 3.6 Norfolk VA to Cape Town South Africa, (Aerosols99) Jan-Feb

1999

46b T-3 3.3 Norfolk VA to Cape Town South Africa, (Aerosols99) Jan-Feb

1999

46 14 T-3 4.0±1.4 Norfolk VA to Cape Town, South Africa (Aerosols99) Jan-Feb

1999

48a MLR-2 8.5 Indian Ocean (INDOEX) Feb-Mar

1999

48b T-3 8.8 Indian Ocean (INDOEX) Feb-Mar

1999

48 15 T-3 4.4±1.7 Indian Ocean (INDOEX) Feb-Mar

1999

49 16 T-3 3.88±0.8 Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

49 17 T-3 0.61±0.14 ‡ Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

49 18 T-3 2.6±0.4 ♦ Pacific Ocean, coastal Asia (ACE-ASIA) Spring

2001

51 19 MLR-2 10.2±0.8 Cranmore Mountain NH Apr–

May, 2000

52 MLR-2 12.85 Southern New Hampshire Jul

2000- Sep 2001
53 20 P 1.5±0.9 10.3 Denver CO Jan 1988Note Method α sp (LAC) Specific

α ap (fine mode) Specific α ap (coarse mode) α ap (LAC) α

ap (Soil) α

ap (POM) Location/Study Time

56 21 M-1 0.37 0.082 Spirit Mountain NV Apr-Sep

1989,
57 M-1 8.6 ( 8.8 ) Linan China Oct-Nov 1999

Footnotes for absorption efficiency table Values reported for a wavelength of 550 nm, unless stated in the notes table. Italicized efficiencies in parentheses correspond to estimates corrected to 550 nm assumin g a λ -1 relationship. Size range and relative humidity (wh en reported) and instruments are stated in the Measurement note table or below

Methods: M-1 refers to measurement method where bsp and mass are both measured M-2 refers to measurement method where bsp is measu red and mass derived from volume distributions T-1 refers to theoretically calculated bsp and spec ific mass derived from number or volume size distri butions T-2 refers to theoretically calculated bsp and mass size distributions per species T-3 refers to theoretically calculated bsp and mass is apportioned to a species from number or volume size distribution
measurements MLR-1 refers to multi-linear regression assuming an internally mixed aerosol model MLR-2 refers to a multi-linear regression assuming an externally mixed aerosol model P refers to partial scattering method

‡ Corresponds to coarse mode (supermicron)

♦ Corresponds to total modes (supramicron, fine + co arse)

1 Three values listed correspond to estimates from P M 2.5 filter mass, summed MOUDI mass and R&P mass, respe ctively (see notes 7a, 7b, and 7c).
2 Eap for EC is for PM2.5 and coarse (PM 10 – PM 2.5 ), respectively. Soil and OC are also coarse.
3 Values correspond to Caltech data and R/V Ronald B rown data (see notes 12a and 12b)
4 Values correspond to Caltech data and R/V Ronald B rown data (see notes 12c and 12d) 5 Values correspond to Caltech data and R/V Ronald B rown data (see notes 12e and 12f)
6 Values correspond to Caltech data and R/V Ronald B rown data (see notes 12g and 12h)
7 Values correspond to R/V Ronald Brown data (see no tes 12i)
8 Average and standard deviation of two polluted air mass events at RH values of 81 % and 77 % (see not es 19a and 19b) 9 Time periods not given in manuscript
10 PM 2.5 O4 and OP fractions for organic carbon and E1 and E2 fractions for EC. Regression performed with inte rcept (see notes 28a and 28b)
11 PM 2.5 O4 and OP fractions for organic carbon and E1 and E 2 fractions for EC. Regression performed without in tercept (see notes 28c and 28d)
12 Comparison of photoacoustic and TOR EC data (see n ote 40a)
13 Comparison of aethalometer and photoacoustic data. Average and standard deviation of days in Dec 1996 and Jan 1997 (see notes 40b and40c)
14 For Dp < 10 μm. Average and standard deviation of values for North America, NH marine, African dust, African dust/biomass burning and biomass burning (see notes 46c-g) 15 For Dp < 1.1 μm. Average and standard deviation of SH Atlantic, SH Indian Ocean, NH Indian Ocean, Eas t Indian Subcontinent, Indian Subcontinent, Arabia, Arabia-I ndian subcontinent, Arabian sea-coastal India (see notes 48c-j) 16 For Dp < 1.1 μm. Average and standard deviation of polluted-Korea/Japan, polluted-Japan, volcano-poll uted, dust+frontal, dust+Korea, dust+Shanghai (see notes 49a-f)
17 For 1.1 < Dp < 10 μm. Average and standard deviati on of polluted-Korea/Japan, polluted-Japan, volcano -polluted, dust+frontal, dust+Korea, dust+Shanghai (see notes 49g-l)
18 For Dp < 10 μm. Average and standard deviation of polluted-Korea/Japan, polluted-Japan, volcano-pollu ted, dust+frontal, dust+Korea, dust+Shanghai (see notes 49m-r) 19 Average and standard deviation of two air masses ( see notes 51a and 51b)
20 Average and standard deviation of two time periods and RH (74 % and 38 %).
21 Computed from data in manuscript

## Absorption Efficiency Method Notes table with furth er details about measurement methods Mass Absorption Efficiency Notes

5 Comparison between aethalometer and photoacoustic technique at a wavelength of 880 nm. (Sept 17- Oct 17, 1999, Big Bend National Park, TX)
7a TEOM PM2.5 mass and Bap measured with a PSAP at a wavelength of 550 nm. Average RH value of 48 %. (Ju ly 30 - Sept 3 1999, Atlanta, GA)
7b PM2.5 filter mass and Bap measured with a PSAP at a wavelength of 550 nm. Average RH value of 48 %. ( July 30 - Sept 3 1999, Atlanta)
7c MOUDI mass (includes sum of all stages and after-f ilter, 0.056 < Dp < 1.78 um). Bap measured with a P SAP at a wavelength of 550 nm. Average RH value of 48 %. (July 30 - Sept 3 1999, Atlanta, GA)
8 PM2.5 EC and dry Bsp from a nephelometer at a wave length of 530 nm. PM2.5 mass and Babs measured by i ntegrating plate laser absorption at a wavelength of 633 nm. Eap for soil, organic carbon are coarse (PM10 –PM2.5). Eap for E C for PM2.5 and PM10, respectively. Soil form not stated. OC multiplier n ot stated.(April-June 1999, Eagle Farm, Brisbane, A ustralia)
12a Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Caltech data. (Feb 11 - March 25, 1999, Kashi dhoo Climate Observatory, Maldives, for low Bsp regime (Bsp < 25 Mm-1))
12b Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Ronald Brown R/V data. (Feb 11 - March 25, 19 99, Kashidhoo Climate Observatory, Maldives, for low Bsp regime ( Bsp < 25 Mm-1))
12c Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Caltech data. (Feb 11 - March 25, 1999, Kashi dhoo Climate Observatory, Maldives, medium Bsp regime (25 < Bsp < 55 Mm-1))
12d Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Ronald Brown R/V data. (Feb 11 - March 25, 19 99, Kashidhoo Climate Observatory, Maldives, medium Bsp regime (2 5 < Bsp < 55 Mm-1))
12e Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Caltech data. (Feb 11 - March 25, 1999, Kashi dhoo Climate Observatory, Maldives, high Bsp regime (Bsp > 55 Mm -1))
12 f Bap is measured with a PSAP RH = 33 % and Dp < 1 u m. Ronald Brown R/V data. Feb 11 - March 25, 1999, Kashidhoo Climate Observatory, Maldives, high Bsp regime (Bsp > 55 Mm -1)) 12g Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Caltech data. (Feb 11 - March 25, 1999, Kashi dhoo Climate Observatory, Maldives, Bay of Bengal Trajectory)
12h Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Ronald Brown R/V data. (Feb 11 - March 25, 19 99, Kashidhoo Climate Observatory, Maldives, Bay of Bengal Trajec tory)
12i Bap is measured with a PSAP at RH = 33 % and Dp < 1 um. Ronald Brown R/V data. (Feb 11 - March 25, 19 99, Kashidhoo Climate Observatory, Maldives, Arabian Sea Trajecto ry)
13a MOUDI size distributions, Eap corresponds to Dp = 0.09 um and density of 1.9. Babs measured by transm ission of light with spectrophotometer, (June -Sept, 1997, Bondville, IL )
13b MOUDI size distributions, Eap corresponds to Dp = 0.16 um and density of 1.9. Babs measured by transm ission of light with spectrophotometer, (June - Sept 1997, Bondville, IL ).
13c MOUDI size distributions, Eap corresponds to Dp = 0.30 um and density of 1.9. Babs measured by transm ission of light with spectrophotometer, (June - Sept 1997, Bondville, IL ).
13d MOUDI size distributions, Eap corresponds to Dp = 0.55 um and density of 1.9. Babs measured by transm ission of light with spectrophotometer, (June - Sept 1997, Bondville, IL ).
13e MOUDI size distributions, Eap corresponds to Dp = 1.0 um and density of 1.9. Babs measured by transmi ssion of light with spectrophotometer, (June - Sept 1997, Bondville, IL ).
13f MOUDI size distributions, Eap corresponds to Dp = 2 .7 um and density of 1.9. Babs measured by transmis sion of light with spectrophotometer, (June - Sept 1997, Bondville, IL ).
16 Bap by AE-9 aethalometer, corrected to 550 assumin g 1/lambda. RH < 50 %. (June 20 - July 10 1996, Sde Boker, Negev Desert, Israel)
19a MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 81 %). Soot size distributions assumed to match nssSO4. (June 19 2000-0700 1992, Santa Maria, Azores a rchipelago, continental polluted air)
19b MOUDI size distributions at ambient humidity (0.32 < Dp < 10 um, RH = 77 %). Soot size distributions assumed to match nssSO4. (June 20 0800-1900 1992, Santa Maria, Azores a rchipelago, continental polluted air)
24a McGee Scientific Aethalometer and thermally analyze d black carbon concentrations at a wavelength of 88 0 nm. (Grenoble, France)
24b McGee Scientific Aethalometer and thermally analyz ed black carbon concentrations at a wavelength of 8 80 nm (Paris, France)
24c McGee Scientific Aethalometer and thermally analyz ed black carbon concentrations at a wavelength of 8 80 nm (Savannah areas, Ivory Coast and Congo)


## Mass Absorption Efficiency Notes24d McGee Scientific Aethalometer and thermally analyz ed black carbon concentrations at a wavelength of 8 80 nm (Western

Mediterranean)
24e McGee Scientific Aethalometer and thermally analyz ed black carbon concentrations at a wavelength of 8 80 nm (Remote Areas (northern tropical Pacific, Mace Head, Ireland; Gre enland)
27a PM2.5 Babs by LIPM and LAC mass. (summer 1990, Tah oma Woods, Mount Rainier National Park, WA)
27b PM2.5 Babs by LIPM and LAC mass. (summer 1990, Mar blemount, North Cascades National Park, WA)
28a PM2.5 Babs by LIPM. Mass corresponds to the O4+OP fractions of OC by TOR. Regression intercept of 3.1 . Wavelength not stated. (Summer 1992, Meadview, Grand Canyon Nation al Park, AZ)
28b PM2.5 Babs by LIPM. Mass corresponds to the E1+E2 fractions of EC by TOR. Regression intercept of 3.1 . Wavelength not stated. (Summer 1992, Meadview, Grand Canyon Nation al Park, AZ)
28c PM2.5 Babs by LIPM. Mass corresponds to the O4+OP fractions of OC by TOR. Regression with no intercep t. Wavelength not stated. (Summer 1992, Meadview, Grand Canyon Nation al Park, AZ)
28d PM2.5 Babs by LIPM. Mass corresponds to the E1+E2 fractions of EC by TOR. Regression with no intercep t. Wavelength not stated. (Summer 1992, Meadview, Grand Canyon Nation al Park, AZ)
38 DMA and OPC dry aligned size distributions (0.04 < Dp < 2 um) and retrieved refractive indices at a w avelength of 530 nm. Eap corresponds to integrated accumulation mode mass an d to PM2.5 EC mass (July-Sept, 2002, Yosemite Natio nal Park, CA)
40a Regression of TOR EC vs photoacoustic Babs at a wa velength of 685 nm. (Jan 3 and 6-9, 1997, Brighton, CO)
40b Regression of BC from Magee Scientific AE-10IM aet halometer BC and photoacoustic Babs at a wavelength of 685 nm (avg Dec 17&18 1996, Brighton, CO)
40c Regression of BC from Magee Scientific AE-10IM aet halometer BC and photoacoustic Babs at a wavelength of 685 nm (avg Jan 3 and 6-9 1997, Brighton, CO)
46a Bap measured with PSAP at RH = 55 % and for Dp < 1 0 um. Mean values for North America, NH marine, dus t, dust/biomass burning, biomass burning. (Jan 14-Feb 8, 1999, Norf olk, VA to Cape Town, South Africa)
46b Size distributions for Dp < 10 um, RH = 55 %. Esp for BC. Reported means for North America, NH marine , dust, dust/biomass burning, biomass burning, (Jan 14 -Feb 8 1999, Norf olk, VA to Cape Town, South Africa)
46c Size distributions for Dp < 1.1 um, RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for North America (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Afr ica)
46d Size distributions for Dp < 1.1 um, RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for Northern Hemisphere marine, (Jan 14 -Feb 8 1999, Norfolk, VA to Cape To wn, South Africa)
46e Size distributions for Dp < 1.1 um, RH = 55 %. BC i ncludes nss-K and associated SO4 and NO3. Mean for African dust, (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Africa )
46f Size distributions for Dp < 1.1 um, RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for African dust/biomass burning, (Jan 14 -Feb 8 1999, Norfolk, VA to Cape T own, South Africa) 46g Size distributions for Dp < 1.1 um, RH = 55 %. BC i ncludes nss-K and associated SO4 and NO3. Mean for biomass burning, (Jan 14 -Feb 8 1999, Norfolk, VA to Cape Town, South Afr ica)
48a Bap measured with PSAP for Dp < 1um at RH = 55 %. Mean for the entire experiment; (Feb-Mar 1999, Arab ian Sea, Bay of Bengal, Indian Ocean -north and south of the ITCZ)
48b Size distributions for for Dp < 10 um and RH = 55 %. Mean for entire experiment. (Feb-March 1999, Ara bian Sea, Bay of Bengal, Indian Ocean, north and south of the ITCZ)
48c Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for SH Atlantic (FebMarch 1999)
48d Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for SH Indian Ocean (Feb-March 1999)
48e Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for NH Indian Ocean, (Feb-March 1999)
48f Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for East Indian Subcontinent (Feb-March 1999) 48g Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for Indian Subcontinent, (Feb-March 1999)
48h Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for Arabia, (FebMarch 1999)
48i Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for Arabia-Indian subcontinent, (Feb-March 1999) 48j Size distributions for Dp < 1.1 um and RH = 55 %. BC includes nss-K and associated SO4 and NO3. Mean for Arabian sea, coastal India, (Feb-March 1999)
49a Size distributions for Dp < 1.1 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean for PollutedKorea/Japan (mid-March to mid-April 2001)


## Mass Absorption Efficiency Notes49b Size distributions for Dp < 1.1 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean for Polluted-Japan

(mid-March to mid-April 2001)
49c Size distributions for Dp < 1.1 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean for Volcano+Polluted (mid-March to mid-April 2001)
49d Size distributions for Dp < 1.1 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean for dust + Frontal (mid-March to mid-April 2001)
49e Size distributions for Dp < 1.1 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean for Dust + Korea (mid-March to mid-April 2001)
49f Size distributions for Dp < 1.1 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean f or Dust + Shanghai (mid-March to mid-April 2001) 49g Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for PollutedKorea/Japan, (mid-March to mid-April 2001)
49h Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for PollutedJapan, (mid-March to mid-April 2001)
49i Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for Volcano+Polluted, (mid-March to mid-April 2001) 49j Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for dust + Frontal (mid-March to mid-April 2001)
49k Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for Dust + Korea (mid-March to mid-April 2001)
49l Size distributions for 1.1 < Dp < 10 um and RH = 5 5 %. EC includes nss-K and associated SO4 and NO3. Mean for Dust + Shanghai (mid-March to mid-April 2001)
49m Size distributions for Dp < 10 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean for PollutedKorea/Japan (mid-March to mid-April 2001)
49n Size distributions for Dp < 10 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean f or Polluted-Japan (mid-March to mid-April 2001)
49o Size distributions for Dp < 10 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean f or Volcano+Polluted (mid-March to mid-April 2001) 49p Size distributions for Dp < 10 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean f or dust + Frontal (mid-March to mid-April 2001) 49q Size distributions for Dp < 10 um and RH = 55 %. E C includes nss-K and associated SO4 and NO3. Mean f or Dust + Korea (mid-March to mid-April 2001)
49r Size distributions for Dp < 10 um and RH = 55 %. EC includes nss-K and associated SO4 and NO3. Mean fo r Dust + Shanghai (mid-March to mid-April 2001)
51a Bap measured with PSAP at 565nm (corrected to 550 nm) at ambient RH (< 50 % typically. EC from TOT. ( April 18 - May 13, 2000, Cranmore Mountain, New Hampshire, for north/n ortheast air masses)
51b Bap measured with PSAP at 565nm (corrected to 550 nm) at ambient RH (< 50 % typically. EC from TOT. ( April 18 - May 13, 2000, Cranmore Mountain, New Hampshire, for west/so uthwest air masses)
52 Bsp from Radiance Research M903 nephelometer at a wavelength of 530 nm. Bap with PSAP at 550 nm. Sulf ate corresponds to ammonium sulfate. POM =1.4*OC from TOT method. Valu es correspond to all measurements. (July 2000-Sept 2001, rural site in southern New Hampshire)
53a MOUDI size distribution (0.03 < Dp < 3.16 um) and ELSIE calculations. RH = 74 %. Wavelength not state d. Interactive efficiency. (Jan 5 1998, Denver, CO, northeasterly flow)
53b MOUDI size distribution (0.03 < Dp < 3.16 um) and ELSIE calculations. RH = 38 %. Wavelength not state d. Interactive efficiency. (Jan 13 1998, Denver, CO, stagnant air mass)
56 Eap is for a ratio of Babs from LIPM and PM2.5 aer osol. Coarse Eap is for 2.5 < Dp < 15 um gravimetri c mass. Ratio computed from data in manuscript. (April-Sept 1989, Spirit M ountain, Nevada)
57 PM2.5 mass and Bap measured with a PSAP at 565 nm f or RH < 40 %. (Oct 28-Nov 20 1999, Linan, China)

## Citations for Mass Scattering and Absorption Effici encies

Citation Mass Scattering Efficiency Citation

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3 Ames, R. B., J. L. Hand, S. M. Kreidenweis, D. E. D ay, and W. C. Malm, Optical measurements of aerosol size distributions in Great Smoky Mountains National Park: Dry aerosol characterization, J. Air and Waste Manage. Assoc., 50 , 665-676, 2000

4 Andreae, T. W., M. O. Andreae, C. Ichoku, W. Maenha ut, J. Cafmeyer, A. Karnieli, and L. Orlovsky, Light scattering by dust and anthropogenic aerosol at a remote site in the Negev desert, Israel, J. Geophys. Res., 107(D2), 10.1029/2001JD900252, 2002

5 Arnott, W. P., H. Moosmuller, P. J. Sheridan, J. A. Ogren, R. Raspet, W. V. Slaton, J. L. Hand, S. M. Kreidenweis, and J. L. Collett, Jr., Photoacoustic and filter-based ambient aerosol light absorption measurements: Instrument comparisons and the role o f relative humidity, J. Geophys. Res., 108(D1)

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6 Bergin, M. H., G. R. Cass, J. Xu, C. Fang, L. M. Ze ng, T. Yu, L. G. Salmon, C. S. Kiang, X. Y. Tang, Y. H. Zhang, and W. L. Chameides, Aerosol rad iative, physical, and chemical properties in Beijing during June 1999, J. Geophys. Res., 106(D16), 17969-17980, August 27, 2001

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