Mineral Dust and Black Carbon at the Summit of Mt. FujiTakahashi, H.(1); Igarashi, Y.(2); Tanaka, Y.(1); Yoshioka, K.(3); Kaneyasu, N. (4); Watanabe, K. (5); Dokiya, Y.(6)(2)Atmospheric Environment and Applied Meteorology Research Department, Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki, 305-0052 Japan, htakahas@mri-jma.go.jp(3) Geochemical Research Department, Meteorological Research Institute(4)Shimane Prefectural Institute of Public Health and Environment Science(5)National Institute of Advanced Industrial Science and Technology(6)Toyama Prefectural University(7)Edogawa University
In order to understand the background level of aerosol concentration and its variability
in the free troposphere,with high temporal resolution,with long-term monitoring,an optical particle counter was installed at the summit of Mt. Fuji (3,776 m a.s.l.) in March 2003. We found two major events of high aerosol concentration detected in first half of 2003.
Utilizing our CTM (MASINGAR), we clarified that one is mineral dust event from Asian continent, and the other is black carbon event from Siberian forest fire.

Introduction

Why Mt. Fuji?

As for monitoring of the atmospheric chemical trace species in the troposphere,“long-term time series observed data“ are not obtained by satellite, lider, balloon oraircraft observations. We have carried out atmospheric chemistry observations at Mt.
Fuji weather station such as
Fog and precipitation chemistryHayashi et al, （2001）Water, Soil and Air Pollut.
Aerosol chemical species
Dokiya et al., (2001) Anal. Sci.
CO and O3
Tsutsumi and Matsueda (2000), Atmos．Environ.
O3 and Be-7
Tsutsumi, Igarsashi, et al.(1998) J. Geophys. Res.
H2O2 and MHP
Yonekura et al. (submitted)
SO2
Igarashi et al.(2004) J. Geophys. Res.

1.
2.
3.
4.

Sole peak (3776m a.s.l.) soars above boundary layer (most of the year)
Located at the downwind region of the Asian source areas of chemical species
No mega-city near the mountain
The weather station facility located at the summit are available

E-W Cross Section of Mountains
Waliguan

Optical Particle Counter (KANOMAX MODEL3886)<merit>Mauna Loalow-cost and maintenance-freesmall, light in weight, and portable by mountain carriers
obtained at 5 channels（d > 0.3, 0.5, 1.0, 3.0, 5.0mm)

Fuji<drawback>Conc. of small particles (r < 0.15mm) is uncertain
Not so wide sensible range(saturated in polluted atmosphere on rare occasions)Parameters of optical properties assumed are fixed.

Previous studies of observation of size-resolved aerosol concentration at
the summit of Mt. Fuji are…
 Composition and size distribution of submicrometer aerosol particles observed on Mt. Fuji in theTateyama

volcanic plumes from Miyakejima : Naoe et al., Atmos. Environ., 37, 3047-3055 (2003) Size-separated aerosol chemistry and water-soluble gases at the summit of Mt. Fuji during July 7-19,

Highest Mt. of Jeju Do

2000, M. Kido et al., ASAAQ2003

But, long-term monitoring of aerosol number concentration at the summit
has not carried out.  In this study, we obtained the data from Feb. to Oct.
2003.

Image from theSpace-shuttle
Columbia(NASA, 2003)

Surroundings

Observed dataMar AprMayComparison of temporal change incation conc. and particle conc.
Relative conc. Of cation

Total volume conc. is dominated by1m-size particles.

5Cation

Na+0.6

K+

4

Mg2+
NH4+

30.4

20.2
1

2003/3/1

2003/3/8

2003/3/15

2003/3/22

2003/3/29

2003/4/5

2003/4/12

2003/4/19

NH4+,K+ rich0And
Small particles dominant(biomass-burning?)

2003/4/26

10000000
1000000

Count in five-minite

In dust case, all size-bins of particles
fluctuate in similar rates.
Slightly smaller variation in small
particles was found.

Simulated dust in time–vertical section(Apr6-20 2003)(by Y. Minami,Ishikawa Agri. Coll.)

nss-Ca2+0.0

OPC10000010000
1000

0 .3 u m (C N T )0 .5 u m (C N T )
1um (C N T )3um (C N T )
5um (C N T )nss-Ca2+,Na+,Mg2+ rich
AndLarge particles dominant(Dust)

100
10
1
2 0 0 3 / 3 /1
0 :0 02 0 0 3 / 3 /1 1
0 :0 02 0 0 3 / 3 /2 1
0 :0 02 0 0 3 / 3 /3 1
0 :0 02 0 0 3 / 4 /1 0
0 :0 02 0 0 3 / 4 /2 0
0 :0 0Mar Apr

MayJundiameter

The numbers of dust-observed cases were very few.
In winter 2002-2003, large amount of rainfall and snowfall was observed in dust
source region.
In spring 2003, severe wind was rarely observed in dust source region.
(Beijing city weather station）

Kosa repoted days in Japan[stations×days]

Large particles dominant in
Asian dust case

Layer N Pres.[hPa]
30
0.5
29
1.0
28
1.5
27
2.0
26
3.0
25
5.0
24
7.0
23
10.0
22
15.0
21
20.0
20
30.0
19
50.0
18
70.0
17
100.0
16
150.0
15
200.0
14
250.0
13300.012400.011500.010600.0
9700.08750.07800.06850.05900.04925.0
3950.0

Small particles dominant inBC cases

Model Description(Model of Aerosol Species IN the Global AtmospheRe)

Corresponding sizes are
0.3um, 0.5um, 1um,3um, 5um

MASINGAR can deal with…
Sulfate（SO2, SO42-, DMS, H2S, CS 2, MSA, DMSO, DMSO2 ・・・GEIA 1B)
Dust, Sea Salt, Carbonaceous（OC, BC）, Radon222, Lead210

Dust01
Dust02
Dust03
Dust04
Dust05
Dust06
Dust07
Dust08Dust09Dust10

0.100
0.158
0.251
0.398
0.691
1.000
1.585
2.512
9.981
6.310

r_max
0.158
0.251
0.398
0.691
1.000
1.585
2.512
9.981
6.310
10.000

0.136
0.215
0.340
0.540
0.855
1.355
2.148
3.405
5.396
8.553

UnderestimatedObservationr_e ffective

Overestimatedsmall↑

Model↓large

2 0 0 3 / 4 /3 0
0 :0 0Good correlation between the data obtainedby OPC and aethalometer (10May.-12Jun.)

Siberian forest fire in spring-summer 2003 discharged heavy smoke. The smoke
reduced the intensity of sunlight in the north Japan.

Aethalometer

Unit[ngC/m3]→Variation of small particles weredominated by black carbon aerosols!

- Burned 21000km2 (three times of Hokkaido in Japan) of the forest- “Smoky, and smell like pyroligneous acid” reported by Mt. Fuji weather station.
- High concentration of aerosols in 3000-4000m a.s.l (Japan Met. Agency)- No cloud was observed, but hours of sunlight was reported 0 widely in north Japan.

Key point… Vertical flux? Gravity settlement?

Height of Mt.Fuji(630hPa)

1000hPa

5-Apr

10-Mar15-Mar20-Mar[ug/m3][ug/m 3]Mainly in 13 Apr

MASINGAR (line) can reproduces the each dust event (dot) intime series, but quantitative skill is bad.

Resolution : T63L30
Pre-run : 2weeks
Horizontal wind is nudged with NCEP40 reanalysis.

r_min

Mainly in 27 Mar

Comparison of the simulated conc. of dustwith observed conc. of aerosol (5-20Apr.)

Model : MASINGAR （Tanaka et al., 2003）

bin<2003>
MonthDays
10
20
3
69
499
52

In this case study, we discuss about the kosaevent detected at the summit on 13 Apr 2003.

Siberian forest fire in 2003

In 13 Apr. (severe Kosa event), our model simulateddense dust on the foot of Mt. Fuji, but the model
underestimated at the altitude of the summit.

Kosa (Asian dust) events in 2003

YearDays
1999
265
2000
727
2001
827
2002
1229
2003
170

Jun



(Diameter)

Volume conc. and its normalized
pattern (Asian dust case)Size-distribution is assumed arbitrarily.

Mean concentration was very low.
High concentration events were detected (increasing a few tens times or more).

Small  middle  large

Air-inlet has been installed at the side of theweather station building. Fresh air transported withwesterly-jet is able to be taken in.
Contamination from mountain climbers arenegligible. The periods when the power generator runs arerecorded and taken into account in a quality-check.

A digital flowmeter (bubble-type) is used to determinate the flow strength, due toevidently higher airflow than standard value written in the operating manual.
No compensation was made for humidity change. (The room where the OPC is installed
is warmer than the open air by 10 – 40 deg C.)

Volume Concentration[The summit of Mt. Fuji, from 21/Mar/2003 to 30/Jun/2003]
The concentration data were obtained every 10 minutes

300hPaInstrument - OPC

At the top of Mt. Fuji, this smoky
event was evident with manual
observation. But the change of allsky solar radiation was not detected
obviously.
OPC saturated often in the period.
This period overlapped with ourintensive observation period in 2003.

Unit[count/5min]

Saturated!

（from N.Kaneyasu, AIST）
OPC

JMA reported reddish sun observed in Hokkaido on 22 May.

Fire location (Emission setting)

Volume conc. and its normalized
pattern (in “BC event”)

Fire locations were assumed basedon the MODIS Satellite and weremanually put in the figure.

Modeled BC and observed
conc. of aerosols
Simulated BC distributions vary
apparently with height.

Simulated BC Time–vertical section (May 2003)

Corresponding levels are

Although higher concentration is found in other altitudes,
highest concentration at the summit was found in 24-25 May.
Good accordance with observation.

500hPa, 630hPa,700hPa, 850hPa
Mt.Fuji is locatedaround 630hPa level.

115Mt.Fuji

Since the fire intensity was unknown, a constant emission
rate was simply assumed
large particles

small particles(BC events)16

comparable

Similar to dust case, size m particles
are predominant in total volumeconcentration.

Mt.FujiBut, small particles increased in “BCevents”.

Apr. 2003

Transport process of BC reaching
the summit on May23-25

May. 2003

Siberia-origin BC came to thesummit with easterly wind!
20May00Z

21May00Z

22May00Z

5/19 00Z 630hPa
BC was transported to Okhotsk sea during the first stage, andnortherly wind brought it to east coast of Honshu (central island ofJapan) via Hokkaido Is. Finally high concentration of BC wasreached the summit from east.

MODIS(NASA)May19 0430Z

24May
18Z

The smoke plume from the forest fire wastransported to south by surface wind, anduplifted intermittently with a trough located in
the north-eastern China and the eastern Siberia.
This uplift brought the plume to the altitude of
the summit of Mt. Fuji (630hPa).

5/19 00Z 850hPa

24May
00Z

23May
00Z

Summary
By monitoring aerosols in the free troposphere, we can depict
long-range transport processes. The summit of Mt. Fuji serves a goodobservational site.
From the monitoring time series, we extracted a dust event andBC event. Our CTM developed for investigating transport processes andradiative forcing was utilized for comparison with observed aerosol
concentration at the summit.
For the dust case, the model reproduced high concentration
events, but the quantitative concentration could not be simulatedadequately. An insufficient precision in vertical transport (includinggravitational settlement) scheme could brought the error.
For the BC event, we found that even manually set BC emission
could reproduce the observed BC. It is indicated that Siberia-origin BC
was transported via Okhotsk sea and Hokkaido to Mt. Fuji.

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