Atmospheric Surface Layer Characterization: 

Preliminary Desert Lapse Rate Study 

22–25 August 2000 

Doyle S. Elliott, Gail Vaucher, 

Jimmy Yarbrough, and David Quintis 

ARL-TR-2994 May 2003 

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Army Research Laboratory 

White Sands Missile Range, NM 88002-5501 

ARL-TR-2994 May 2003 

Atmospheric Surface Layer Characterization: 

Preliminary Desert Lapse Rate Study 

22–25 August 2000 

Doyle S. Elliott, Gail Vaucher, 

Jimmy Yarbrough, and David Quintis 

Computational & Information Sciences Directorate 

Battlefield Environment Divison 

Boundary Layer Meteorology Branch 

Approved for public release; distribution is unlimited.
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Atmospheric Surface Layer Characterization: Preliminary Desert Lapse Rate 

Study 22-25 August 2000 

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6. AUTHOR(S) 

Doyle S. Elliott 

Gail T. Vaucher 

Jimmy Yarbrough 

David Quintis

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U.S. Army Research Laboratory 

Computational & Information Sciences Directorate 

Battlefield Environment Division ATTN: AMSRL-CI-EB 

White Sands Missile Range, NM 88002-5501

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14. ABSTRACT 

Results of the August 2000 Desert Lapse Rate (DLR) Experiment are presented. The DLR Experiment was performed to 

document the night-to-day transition effects on the desert Atmospheric Surface Layer (ASL). During the DLR Experiment, 

simultaneous 32 m and 2 m thermodynamic and wind data were gathered 2 hrs prior to, through 2 hrs after sunrise. Solar 

radiation data were also gathered over the Experimental Period. A GPS radiosonde was launched at the beginning of the 

atmospheric neutral event after sunrise to determine the depth of the isothermal layer. Lapse rate changes characterized the 

transition of the Night-Day lower-atmospheric Chihuahuan Desert conditions and are presented in the results. 

15. SUBJECT TERMS

atmospheric lapse rate, surface layer, neutral event, solar radiation, nocturnal-diurnal transition 

16. SECURITY CLASSIFICATION OF:

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Doyle S. Elliott 

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iii 

Contents 

REPORT DOCUMENTATION PAGE ii 

List of Figures iv 

List of Tables iv 

Acknowledgements iv 

Summary 1 

1. Introduction 2 

1.1 Project Name/Experiment ...............................................................................................2 

1.2 Methods...........................................................................................................................3 

2. Met Sensors Used 3 

2.1 Upper Air Equipment Used.............................................................................................3 

3. Results and Discussion 3 

3.1 Case I: 22 August 2000 ..................................................................................................3 

3.1.1 Nighttime............................................................................................................ 3 

3.1.2 Sunrise through NE ............................................................................................ 4 

3.1.3 Daytime (Late Morning) .................................................................................... 4 

3.2 Case II: 23 August 2000.................................................................................................5 

3.2.1 Nighttime........................................................................................................... 5 

3.2.2 Sunrise through NE ............................................................................................ 5 

3.2.3 Daytime (Late Morning) .................................................................................... 6 

3.3 Case III: 25August 2000..................................................................................................6 

3.3.1 Nighttime............................................................................................................ 6 

3.3.2 Sunrise through NE ........................................................................................... 7 

3.3.3 Daytime .............................................................................................................. 7 

4. Conclusions 7 

5. Recommendations 7 
iv

6. References 8 

Appendix A - Project Plan/Method/Schedule (Case listing) 9 

Appendix B - Sensor Data Plots by Cases 13 

Appendix C- Sun Position (Elevation-Azimuth Angle) Tables (COMPASS) by Cases 17 

Acronyms 18 

List of Figures 

Figure B1. Tower temperature versus wind, 8/22/2000. .............................................................. 13 

Figure B2. Tower temperature versus solar radiation, 08/22/2000 .............................................. 14 

Figure B3. Tower temperature versus wind, 08/23/2000 ............................................................. 14 

Figure B4. Tower temperature versus solar radiation, 8/23/2000 ................................................ 15 

Figure B5. Tower temperature versus solar radiation, 08/25/2000 .............................................. 15 

Figure B6. Tower temperature versus wind, 08/25/2000 ............................................................. 16 

List of Tables 

Table C1. Sun Angle data: at Sunrise (SR) and NE .................................................................... 17 

Table C2. Sun Angle data: at Sunrise and NE.............................................................................. 17 

Table C3. Sun Angle data: at Sunrise and NE.............................................................................. 17
v 

Acknowledgements 

We would like to express appreciation for Mr. Fred Wilson of the White Sands Missile Range 

Meteorological Team and his assistance in loaning needed sensors to this effort. Additional 

thanks go to Mr. Alfred Gutierrez and SFC Deryck James for their assistance in executing the 

experiment. 
1 

Summary 

Results of the August 2000 Desert Lapse Rate (DLR) Experiment are presented. The DLR 

Experiment was performed to document the night-to-day transition effects of the Atmospheric 

Surface Layer (ASL), and to support the Vaucher NE (Neutral Event) Prediction Model. During 

the DLR Experiment, simultaneous 32 m and 2 m thermodynamic and wind data were gathered 2 

hrs prior to, through 2 hrs after sunrise. Solar radiation data were also gathered over the 

Experimental Period. A Global Positioning System radiosonde was launched at the beginning of 

the atmospheric NE after sunrise to determine the depth of the isothermal layer. Lapse rate (LR) 

changes characterized the transition of the Night-Day lower-atmospheric Chihuahuan Desert 

conditions, and are presented in the results, which indicated Night and Daytime data had less LR 

variability than the Twilight-through-NE data. The experiment, though generally successful, 

should be continued for a greater length of time and with a larger and more complete sensor 

array. The study is relevant to the U.S. Army’s efforts, as the ASL transitional phenomena and 

periodicity affects those involved in Target Acquisition, Surveillance, and Chemical/Biological 

Transport and Diffusion. 
2 

1. Introduction 

1.1 Project Name/Experiment 

On 22–25 August 2000, the U.S. Army Research Laboratory conducted a Desert Lapse Rate 

(DLR) Experiment at the 100 ft Tower Site, White Sands Missile Range (WSMR), NM. This 

Experiment was also a feasibility study for a research project that focuses on forecasting the 

Atmospheric Neutral Events (NE) (Vaucher et al., 2002). A NE occurrence is defined, for our 

purposes, by a transitional neutral lapse rate in the Atmospheric Surface Layer (ASL); usually 

when the nocturnal surface inversion breaks down in transition to the unstable diurnal profile, or 

when the diurnal unstable profile cools in transition to the nocturnal stable layer (Stull, 2000, p. 

72–74). To quote G.T. Vaucher, “The term Neutral Event or NE comes from the implied 

atmospheric stability being neither unstable nor stable. Later, these events were more correctly 

referred to as Surface Layer Stability Transitions or just Stability Transitions.”(Vaucher et al., 

2002) 

The NE is commonly associated with atmospheric refractivity and visibility factors. 

Atmospheric refractivity during the nocturnal-diurnal transition typically changes from 

abnormal-to-normal propagation, depending upon the severity of the nocturnal inversion layer’s 

lapse rate. Clear sky at night facilitates surface radiation, commonly leading to an ASL 

temperature inversion associated with a marked decrease of humidity with height (Battan, 1973). 

After sunrise, the surface warms to form a very thin superadiabatic layer over the first few 

centimeters above surface, and the morning inversion “erodes” from the surface upwards 

(Munn, 1966). The transition to the NE occurs more swiftly after the thin superadiabatic layer 

just above surface loosens surface “bubbles” of air, so that the layer from approximately 2 m to 

200 m is warmed due to shear-driven entrainment (Angevine, 2001). From the perspective of 

radar propagation, the ASL affects propagation adversely when the nocturnal inversion is strong, 

and propagation returns to normal after the inversion breaks, during and after the NE (Battan, 

1973). From the perspective of visibility, the lower atmosphere has less optical turbulence, 

evidenced by Cn

2

 minima, during the NE transition (Vaucher, 1994). This transition typically 

lasts for a few minutes, when the ASL lapse rate becomes adiabatic, as opposed to the longer 

durations of the stable nocturnal (inversion) or unstable diurnal (superadiabatic) lapse rate in the 

ASL (Munn, 1966). 

The DLR Test mission was to quantitatively characterize the lowest atmospheric layer in a desert 

environment by studying the lapse rate changes during the summertime night-to-day transition 

period. For specific information on the experimental plan and method, refer to Appendix A. 

While the dataset for this experiment specifically indicates local, seasonally pertinent trends 

peculiar to the experiment site, broader inferences could be made when more data are available 

for analysis. Three cases of data are presented: 22, 23 and 25 August 2000. The analysis begins 

with a review of the cases' large-scale atmospheric conditions, and continues with a decrease in 

the resolution of the observations until a review of the actual data collected is presented. The 

discussion of actual data is presented in three temporal subsets: nighttime, sunrise-to-NE, and 

daytime. 
3 

1.2 Methods 

The arid Test site had the Organ mountains (closest were approximately 3 miles) to the west and 

southwest that rose about 1500 m above the 1213 m (Mean Sea Level) desert location. 

Meteorological (Met) sensors were mounted on a 100 ft wooden tower at the 35 m and 2 m 

levels. Three radiosonde launches per day were executed within 80 m of the tower. These 

launches were targeted for 0500 Mountain Daylight Time (MDT), NE (~0735 MDT), and 0900 

MDT. Surface observations were taken at each radiosonde launch and at hourly intervals. 

2. Met Sensors Used 

T-RH sensors at 2 m and 35 m were Vaisala model HMP35AC probes with solar radiation 

shields. The wind was monitored at 35 m by an R.M. Young 05103 wind monitor, and at surface 

by the ML-433/PM anemometer. The solar pyranometer used was the Weathertronics model 

3020, which was mounted at the 35 m level. 

2.1 Upper Air Equipment Used 

The Vaisala MW12 rawinsonde set was used with Vaisala RS80-15G radiosondes. Balloons 

used were 800g (mfr. Totex) for the 0500 MDT release, and 200g Totex balloons for the other 

releases. Each radiosonde was simultaneously tracked by our MW12 and by the WSMR Met 

Team’s Global Positioning System-upgraded Vaisala Digicora MW11. 

3. Results and Discussion 

3.1 Case I: 22 August 2000 

On 22 August, 2000, a dry subsiding air mass around the southern side of a subtropical high 

pressure system gave WSMR, NM stable conditions characterized by clear to partly cloudy 

skies, light winds, and temperatures near the seasonal averages (WSMR Forecast Website, 

2000). The nocturnal drainage flow from the Organ Mountains caused light, predominantly 

northwesterly winds until the southeasterly diurnal regime took over approximately 2 hours after 

sunrise. Local sunrise (SRL) occurred at 0638 MDT (USNO Website, 2000). 

3.1.1 Nighttime 

During the pre-dawn data collection, drainage flow from the Organ Mountains continued 

consistently with only a few brief lulls throughout this nocturnal period. As the twilight 

brightened the horizon, the wind shifted from northwest to easterly and decreased in velocity 

with more lulls. Data from Appendix B, figures B1 and B2, indicated the following summary 

observations for the period: The 35 m level minus 2 m level Temperature difference (Delta-T) 

for the period 0415–0545 MDT remained between 2.5 °C and 3.1 °C, averaging 2.7 °C. The 

average 2 m–35 m lapse rate (LR) was +76.0 °C/km for the same period. The Delta-T average 
4 

from 0415–0629 MDT was 2.8 °C. Just prior to dawn, the Delta-T increased to 3.4 °C. The 

0510 MDT radiosonde revealed the inversion depth to be about 40 m, and ran from a surface 

temperature of 20.9 °C to 23.1 °C at the top of the inversion. The LR for this inversion was 

+55.0 °C/km; and from the top of the inversion to 4.725 km Above Ground Level, the LR was a 

more typical desert LR of –7.0 °C/km. 

3.1.2 Sunrise through NE 

The solar radiation sensor indicated no increase in solar radiation until approximately 0629 

MDT. The average Delta-T from 0629–0638 MDT was 3.2 °C. Nighttime sky conditions (0510 

MDT) were clear. By 0650 MDT, a thin cirrus band was visible on the eastern horizon and 1/10 

stratocumulus was noted to the west. 

The neutral event (NE) data collection was comprised of the data collected between SRL and 

0845 MDT. This period was characterized by very light winds, which became slightly stronger 

and southeasterly after 0840 MDT when diurnal warming allowed coupling of the lowest layers. 

Fair skies and seasonal temperatures prevailed. The 35 m wind speed dropped to zero at 0650 

MDT, and for the span of 0650–0708 MDT, the wind speed averaged 0.5 m/s. During this 

period, the Delta-T began to decrease (from 3.9 °C to 2.9 °C) due to surface warming and stable 

35 m temperatures. The 35 m temperature varied by only 0.3 °C, while the 2 m temperature rose 

0.7 °C. From 0650 MDT until the NE at 0755, the Delta-T decreased from 3.9 °C to zero, an 

average decrease of .06 °C/min. A false NE was recorded between 0830 and 0845 MDT, which 

was due to a lull combined with solar heating of the roof area of the tower where the 35 m 

sensors were placed. The slope of solar radiation versus time reached a near maximum and 

remained nearly linear from 0730–0845 MDT. Solar radiation at 0730 measured 98.5 W/m2

, and 

at 0845 MDT measured 362.2 W/m2

. Solar heating at the surface began to effect an increase in 

the 2 m temperature at 0654 MDT, and from 0700 MDT until the NE there was an increase of 

4.5 °C. The 0735 MDT radiosonde revealed a –14.3 °C LR from 0–49 m, where the surface 

temperature was 22.5 °C and the 49 m temperature was 21.8 °C. The next data point at 83 m 

was 22.5 °C, yielding a zero lapse from surface. The LR from the top of the inversion to 4.715 

km AGL was –6.5 °C/km, or 0.44 °C/km less than the 0510 MDT ascension indicated. The sun 

angle at NE was somewhat higher in this case than that of the other two cases presented (see 

appendix C), since the NE timing was evidently affected by the cirrus veiling the sun’s disk in 

the east just after sunrise, and by clear nighttime conditions allowing the soil surface to cool 

radiatively. The temperature traces from about 0740 MDT may be peculiarly affected by a lull 

during that period, which may have caused the timing of the NE to be reported later due to an 

artifact of equipment thermal differences between the tower top and 2 m setup. This apparent 

artifact during lulls is seen again after NE, as false NE caused by the unequal temperature 

increase at the 35 m level due to the rooftop’s thermal properties versus those of the ground’s. 

3.1.3 Daytime (Late Morning) 

The subsequent diurnal data spanned 0845–0959 MDT. For that period, the sky condition 

continued to be fair, and slightly stronger southeasterly breezes began in contrast to the earlier 

period of northwesterlys. The slopes of both the 2 m and 35 m temperature trends became 

approximately equal between 0845–0959 MDT. Note that two false NE’s were recorded at 0915 

and 0942 MDT, both when the wind fell to near-zero velocity briefly and allowed the thermal 

properties of the tower roof area to affect the temperature sensor mounted there. The sky 
5 

condition at 0920 had 2/10 cirrus west and north, but clear overhead. The solar time series data 

continued to be nearly linear during 0845–0912 MDT (an average 3.5 W/m2

/min increase for the 

period). The slope decreased during 0912–0959 MDT to an average 3.0 W/m2/min increase. 

The 0920 MDT radiosonde data indicated a super-adiabatic layer off surface to 40 m (LR = 

–112.8 °C/km), which the tower data reported at –13.7 °C/km. The vast difference may be 

attributed to the fact that the surface temperature for the balloon was collected at 1 m instead of 2 

m, and that the radiosonde sensors do not have the same degree of precision as the fixed tower 

Temperature-Relative Humidity (T-RH) probe. Errors in lapse rate are also magnified as the 

scale of the measurements decreases, i.e., the error in a 50 m vertical layer appears to have 20 

times the magnitude than the same amount of error between two data points that are 1 km apart 

vertically. 

3.2 Case II: 23 August 2000 

On 23 August, 2000, southeasterly monsoonal flow circulating around a high-pressure ridge 

brought moisture mainly to Arizona, Utah, and western New Mexico, and to a lesser extent to 

WSMR (WSMR Forecast Website, 2000). Early morning sky conditions featured altocumulus 

and cirrus moving westerly over WSMR and orographic stratocumulus hung above the 

mountains. 

3.2.1 Nighttime 

The pre-dawn conditions were characterized by light and variable winds at the surface, a slowly 

rising barometer, and seasonal temperatures. The Delta-T averaged 2.7 °C between 0415–0638 

MDT. When the 35 m winds changed from northerly to southwesterly between 0545–0550 

MDT, the 35 m temperature dropped approximately 1.5 °C in three minutes, an effect that could 

possibly be attributed to drainage flow from the Organ Mountains. The 0456 MDT radiosonde 

data revealed a strong but shallow inversion of 4.6 °C from surface to 60 m AGL, a LR of +76.7 

°C /km. The LR from the top of the inversion to 3407 m averaged –7.1 °C /km. The solar 

radiation data revealed no increase in radiation until 0623 MDT. The Delta-T average from 0415 

to 0638 MDT was 3.6 °C, and the average LR then was +103.4 °C/ km. 

3.2.2 Sunrise through NE 

The NE occurred at 0735 MDT. The NE data were comprised of the collection between SRL 

(0638 MDT), and 0845 MDT. At SRL, thin cirrus were observed above the eastern horizon, and 

1/10 altocumulus were overhead moving westward. This case exhibited the earliest NE of the 

three cases (see sun angle data, Appendix C). The wind was northeasterly at 2–4 m/s, becoming 

easterly, then southeasterly and decreasing to southerly at 2 m/s at the NE. The 35 m 

temperature remained relatively stable for the period, increasing only 1 °C from 0638–0800 

MDT. The 2 m temperature, however, rose nearly 6.9 °C in the same period. From 0638–0735 

MDT the 2 m temperature rose 5.2 °C, and the minimum occurred at 0640 MDT. The LR 

maximum was +130.8 °C/km at 0643 MDT. The Delta-T decreased by an average .08 

°C/minute from 0640–0735(NE). The warming at 2 m appeared to coincide with a decrease in 

the east wind component and an increase in the south wind component from approximately 

0700–0730 MDT. Solar radiation at 0730 measured 120.0 W/m2

 and at 0845 measured 383.4 

W/m2

. The solar radiation time series was nearly linear from 0730–0845 MDT, with small 
6 

variances after NE due to thin clouds passing. Solar heating at the surface began to effect an 

increase in the 2 m temperature at 0644 MDT, and from 0700 MDT until the NE there was an 

increase of 4.7 °C. 

The sky at the 0730 MDT radiosonde launch was clear overhead, with few thin cirrus east, and a 

few stratocumulus over the mountains west were dissipating. The sunlight was unobstructed by 

clouds at the tower site. Surface was calm. The surface temperature at launch was 21.2 °C, 

Relative Humidity was 45%, and pressure 885.8 mb. For complete tower data, refer to Appendix 

B. The temperature profile near surface indicated a 0.6 °C inversion at 55 m, where the LR was 

+10.9 °C/km. From the top at 55 m to 4.75 km AGL, the LR averaged –6.0 °C/km. There was 

an isothermal layer centered at 2 km AGL. 

3.2.3 Daytime (Late Morning) 

The diurnal data from 0845–0953 MDT showed similar tower-temperature time-series slopes to 

that of 22 August. The Delta-T averaged –0.8 °C, and the average LR was a super-adiabatic 

–23.1 °C/km. This period saw a decrease in 35 m wind velocity until the end of the collection 

period at 0951 MDT, when there was a 5 m/s gust. There were false NE’s during brief lulls. 

The 0856 MDT radiosonde was launched under clear skies, 25.0 °C surface temperature, wind 

2m/s from 45°, and pressure 886.6 mb. The data indicated a super-adiabatic layer of 3.3 °C from 

surface to 66 m, for a LR of –50.0 °C/km. The tower data indicated a LR of –22.0 °C/km for 

that time. 

3.3 Case III: 25August 2000

On 25 August, 2000, an upper ridge overhead and to the east continued to suppress convection 

(WSMR Forecast Website, 2000). The sky condition was mostly sunny with patches of 

altocumulus and cirrus. Temperatures were near seasonal, and winds were light and 

northwesterly. Data from Appendix B, figures B5 and B6, indicated the nocturnal drainage flow 

was consistently from the northwest with few lulls, and averaged 3.1 m/s from 0430–0600 MDT. 

Clouds on the horizon obscured SRL. 

3.3.1 Nighttime 

The pre-dawn data collection was characterized by the consistent drainage flow and by the 

decrease in wind velocity between 0600–0639 MDT. Data from Appendix B, figures B5 and B6, 

indicated the following: The average wind velocity for the period was 0.9 m/s, a contrast with 

the period 0430–0600 MDT, where the average was 3.1 m/s. The temperatures from 0430–0600 

MDT ran from 21.0 °C to 21.6 °C at 35 m, and from 18.6 °C to 19.4 °C at 2 m. From 0600–

0639 MDT, the temperatures decreased from 21.6 to 19.7 °C at 35 m, and from 18.6 °C to 17.0 

°C at 2 m. The Delta-T averaged from 0431–0639 MDT was 2.2 °C, and the average LR was 

+87.7 °C/km. 

The 0501 MDT radiosonde revealed an inversion from 0–72m AGL, and an isothermal layer 

from 72 m–267 m. The 2 m temperature was 18.9 °C, the 34 m temperature was 23.8 °C, and 

the 72 m temperature and 115 m temperature were 24.4 °C. The LR from 0–72m was +76.3 

°C/km (tower LR was +101.5), and from 267 m to 3744 m the LR averaged -7.5 °C/km. The 

winds were northerly from 0–1 km, and southerly from 1–5 km (AGL). 
7 

3.3.2 Sunrise through NE 

The data segment including the NE conditions spanned 0639–0900 MDT. The NE occurred at 

0751 MDT. The period was characterized by a consistent decrease in wind velocity from 0720–

0800 MDT, and cloud cover, up to 4/10 altocumulus, affected solar radiation. After NE, until 

0900 MDT, the winds remained very light, in contrast to the first two days of data. 

The 0748 MDT radiosonde data recorded a 1.2 °C inversion from 0–324m, LR = 3.7 °C/km. 

The 0–93 m layer was nearly isothermal (21.4 °C at 0 m, 21.3 °C at 40 m, and 21.5 °C at 93 m). 

The LR from 324–3754 m AGL averaged –7.0 °C/km. The 0748 MDT tower LR was +8.5 

°C/km. 

3.3.3 Daytime 

No daytime data were taken for this period, as the experiment was forced to terminate due to 

range mission requirements. 

4. Conclusions 

The Night and Daytime data showed less LR variability than the Twilight-through-NE data. The 

Max LR occurred after SR on 22 August, just before SRL on 23 August, and at night on 25 

August. The first two Test days reported a maximum wind within 1 hour after SRL; and 25 

August showed the wind max occurring at night. A thin veil of cirrus hovering over the eastern 

horizon impacted the NE timing by delaying the NE. The presence of the clouds was easily 

noted in the solar radiation plots, especially on 25 August. While the Delta-T on 23 August was 

the greatest of the 3 cases, the NE for that case occurred significantly earlier than the other two 

cases. Wind velocity peaked and shifted during this case between SRL and NE. Perhaps the 

more rapid occurrence of the NE was a function of the atmospheric mixing implied in the 

increased wind velocity. 

5. Recommendations 

The experiment, though generally successful, should be continued on a larger scale both 

temporally and spatially, i.e., the next experiment should be continued for a greater length of 

time and with a larger and more complete sensor array. It is recommended that at least three 

instrument towers be fitted with wind heads, T-RH sensors, soil temperature sensors, solartracking pyranometers, scintillometers, and total-sky imagers. Sub-experiments using this 

instrument tower array should be conducted seasonally to document seasonal effects of solar 

radiation on the desert environment lapse rate changes. The benefit of these data to the 

improvement of the Vaucher NE Prediction Model would be amplified by the use of a database. 

The prediction of both the occurrence and duration of the NE could be of benefit in decision-aid 

technology. 
8 

6. References 

Angevine, Wayne M.; Baltink, H.K.; Bosveld, F.C. Observations of the Morning Transition of 

the Convective Boundary Layer. Boundary-Layer Meteorology 2001, 101, 209–227. 

Battan, Louis. Radar Observation of the Atmosphere; University of Chicago Press: Chicago, 

1973. 

COMPASS version 1.2 (freeware). 

Elliott, Doyle S.; Vaucher, G.T. Desert Lapse Rate Experiment, Test Plan and Method, Internal 

Document; U.S. Army Research Laboratory: White Sands Missile Range, NM, 2000. 

Forecast for White Sands Missile Range. http://weather.wsmr.army.mil/public/fcst.txt (accessed 

22–25 August, 2000). 

Munn, R.E., ed. Descriptive Micrometeorology. Supplement 1 to Advances in Geophysics. 

Academic Press: New York, 1966. 

Stull, Roland B. Meteorology for Scientists and Engineers, 2nd ed.; Brooks/Cole: Pacific Grove, 

CA, 2000. 

Vaucher, Gail-Tirrell; Endlich, Robert. Forecasting/Modeling the Atmospheric Optical 

Turbulence Neutral Events over a Desert Environment, Proceedings of the 1994 Battlefield 

Atmospheric Conference, U.S. Army Research Lab, White Sands Missile Range, NM, Nov 

29-Dec 1, 1994. 

Vaucher, Gail-Tirrell; Raby, John. Exploiting Environmental Conditions: Atmospheric Stability 

Transition Forecasting, Proceedings of the 23rd Army Science Conference, Orlando, FL, 

2002 Dec 2-5, 2002. White Sands, New Mexico Rise and Set for the Sun. 

http://weather.wsmr.army.mil/textdata/srss.txt (accessed 20 August, 2000). 
9 

Appendix A - Project Plan/Method/Schedule (Case listing) 

DESERT LAPSE RATE EXPERIMENT 

[Subset of 00 Aug - Mobilizing Local Meteorological Profile Module Test] 

(Last Rev: 00 June 29, Elliott/Vaucher) 

DESERT LAPSE RATE EXPERIMENT MISSION OBJECTIVE: To quantitatively characterize the 

lowest atmospheric layer in a desert environment, by studying the lapse rate changes (atmospheric 

stability) during the summertime night to day transition period. 

DESERT LAPSE RATE EXPERIMENT PLAN: 

Part I: Assemble and test two surface sensors and a solar radiation instrument in a 

 controlled environment. 

Part II: Install and test sensors at the Thompson 100 Ft Tower Site. 

Part III: Run Desert Lapse Rate Experiment at the Thompson 100 Ft Tower Site. 

Part IV: Analyze and publish results. 

DESERT LAPSE RATE EXPERIMENT METHOD: 

Part I: PreTest (Completion target date: 7-14-00).

(1) Assemble two surface sensor instrument systems in a controlled environment. 

(2) Run side-by-side Pre-Tests to establish precision of two sensor units. 

(3) Develop software to simultaneously report (and compare?) data from sensor units. 

(4) Assemble Pyranometer and develop software to acquire data. 

Part II: PreTest (Completion target date: 8-11-00).

(1) Install sensor unit onto 32m level of Thompson Site Tower with solar radiation instrument. 

(2) Install 2m level sensor unit. 

(3) Simultaneously collect thermodynamic and wind data at the 32m and 2m levels at the Thompson Site 

100 Ft Tower. 

(4) Run sample test to calculate Delta-T and Atmospheric Lapse Rate. 

(5) Setup and test functionality of rawinsonde system. 

Part III: Test (Completion target date: 8-25-00).

(1) Simultaneously collect thermodynamic/wind data at the 32m and 2m levels at the Thompson Site 100 

Ft tower, over a time span of Sunrise plus and minus 2 hours. 

(2) Launch rawinsonde data during the Atmospheric Neutral Event. 

(3) Calculate atmospheric lapse rate and plot a timeseries of values. 

(4) To compare measurements with the rawinsonde data. 

Part IV: Post-Test (Completion target date: 12-14-00).

(1) Analyze plots generated. 

(2) Publish results (AMS paper and/or Technical Report). 

Test Plan/Method/Schedule Reviewed by: 

Initial Date Team Member Initial Date Team Member

_____ ________ Elliott _____ ________ Yarbrough 

____ ________ Quintis _____ ________ Vaucher 
10

00 AUG - MOBILIZING LOCAL METEOROLOGICAL PROFILE MODULE TEST 

TEST SCHEDULE: [00 Aug 22-25] 

(Last Rev: 00 Aug 21, Vaucher) 

To better coordinate the LMPM Test, the following is a schedule of events for each day. 

PRE-TEST

16 Aug 100 Ft Tower, Install High Speed Trailer. 

TEST: 

21 Aug, Monday 0800-1200, Bldg 19472, Install hardware into HMMWV. 

 0900-1000: MPSMAIN (Yarbrough, Quintis) 

 1000-1030: Marwin (Yarbrough, Elliott) 

 1100-1245, Transport equipt to 100 Ft Tower, Setup all Equipment. 

1247 100 Ft Tower, DATA COLLECTION [C-station/ARL RAOB Lauch]. 

1400-COB 100 Ft Tower/Bldg 1622, Finish Sfc sensor install/Misc action items. 

22 Aug, Tuesday 0400 Bldg 1622, Leave for site from back door. 

0415-0500, 100 Ft Tower, Pre-Test checkout of individual systems, Raob Prep. 

 0500-0600, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0600-0630, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0630-0700, 100 Ft Tower, Raob preparation: Slow ascent rate. 

0700-0800, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0800-0830, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0830-0900, 100 Ft Tower, Raob preparation. 

0900-1000, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 1000-1030, 100 Ft Tower, Data Transfer, Plots generated and printed. 

1030-1100, 100 Ft Tower, ALL-HANDS Mtg to update next day action items. 

1100-1300, Bldg 1622, Post-Test Analysis, Normal Day activity. 

23 Aug, Wednesday 0400-0500, 100 Ft Tower, Pre-Test checkout of individual systems, Raob Prep. 

 0500-0600, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0600-0630, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0630-0700, 100 Ft Tower, Raob preparation: Slow ascent rate. 

0700-0800, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0800-0830, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0830-0900, 100 Ft Tower, Raob preparation. 

0900-1000, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 1000-1030, 100 Ft Tower, Data Transfer, Plots generated and printed. 

 1030-1200, Bldg 1622, BMMT(Modeling Team) Annual Branch/Div Review. 

1200-1230, Bldg 1622, ALL-HANDS Mtg to update next day action items. 
11

24 Aug, Thursday 'Down day' due to Range mission. 

25 Aug, Friday 0400-0500, 100 Ft Tower, Pre-Test checkout of individual systems, Raob Prep. 

 0500-0600, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0600-0630, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0630-0700, 100 Ft Tower, Raob preparation: Slow ascent rate. 

0700-0800, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 0800-0830, 100 Ft Tower, Data Transfer, Plots generated and printed. 

0830-0900, 100 Ft Tower, Raob preparation. 

0900-1000, 100 Ft Tower, DATA COLLECTION, Raob Launch. 

 1000-1030, 100 Ft Tower, Data Transfer, Plots generated and printed. 

1030-1100, 100 Ft Tower, ALL-HANDS Mtg. 

1100-1230, 100 ft Tower/Bldg 19472, Pack-up gear/Transport to Bldg 19472. 

1230-1300, Bldg 19472, Off-load gear. 

INTERNAL PROJECT REVIEW (IPR): EACH POC REPORT EVALUATION of their piece. 

28 Aug, Monday 0800-0900, Bldg 1622, Prepare IPR questions: 

1. Improvements done since 00 May Test. 

2. Lessons learned from this LMPM Test. 

3. Action Items needing to be addressed & suggested POC. 

4. Constructive comments/suggestions. 

0900-1100, Bldg 19472, ALL-HANDS Meeting. 

_____________ Creegan _____________ Gutierrez 

_____________ Elliott _____________ Quintis 

_____________ Jameson _____________ James 

_____________ Yee _____________ Measure 

_____________ Vaucher (Last Reviewer) _____________ Brown 
12

IPR: 00 Aug-Mobilizing LMPM Test 

(00 Aug 22-25) 

 Name: ______________________ Date: _________ 

Sub-Experiment Title: _________________________________ 

POC for: _____________________________________________ 

1. Improvements done since 00 May LMPM Test. 

2. Lessons learned from this LMPM Test. 

3. Action Items needing to be addressed and a suggested POC for 

each Action Item. 

4. Constructive comments/suggestions. 
13

Appendix B - Sensor Data Plots by Cases 

Case 1 

100' Tower temp/wind 8/22/2000

-5

0

5

10

15

20

25

30

4.250 4.750 5.250 5.750 6.250 6.750 7.250 7.750 8.250 8.750

JulianDayMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

E-W wind (m/s) 

N-S Wind (m/s)

Figure B1. Tower temperature versus wind, 8/22/2000. 
14

100' Tower temp/solar 8/22/2000

-5

0

5

10

15

20

25

30

35

40

45

4.250 4.750 5.250 5.750 6.250 6.750 7.250 7.750 8.250 8.750

timeMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

solar/10

Figure B2. Tower temperature versus solar radiation, 08/22/2000. 

Case 2 

100' Tower temp/wind 8/23/2000

-10

-5

0

5

10

15

20

25

30

4.250 4.750 5.250 5.750 6.250 6.750 7.250 7.750 8.250 8.750

timeMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

E-W wind (m/s) 

N-S Wind (m/s)

Figure B3. Tower temperature versus wind, 08/23/2000. 
15

100' Tower temp/solar 8/23/2000

-10

0

10

20

30

40

50

4.250 4.750 5.250 5.750 6.250 6.750 7.250 7.750 8.250 8.750

timeMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

solar/10

Figure B4. Tower temperature versus solar radiation, 8/23/2000. 

Case 3 

100' Tower temp/solar 8/25/2000

-5

0

5

10

15

20

25

30

35

40

45

50

4.25 4.75 5.25 5.75 6.25 6.75 7.25 7.75 8.25 8.75

timeMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

solar/10

Figure B5. Tower temperature versus solar radiation, 08/25/2000. 
16

100' Tower temp/wind 8/25/2000

-10

-5

0

5

10

15

20

25

30

4.25 4.75 5.25 5.75 6.25 6.75 7.25 7.75 8.25 8.75

timeMDT (dec)

temp deg C

tempC (top)

tempC (bottom)

E-W wind (m/s) 

N-S Wind (m/s)

Figure B6. Tower temperature versus wind, 08/25/2000. 
17

Appendix C- Sun Position (Elevation-Azimuth Angle) Tables (COMPASS1) by 

Cases 

Case 1 

 Table C1. Sun Angle data: at Sunrise (SR) and NE. 

 

Sun Elevation Angle 

(degree) 

Azimuth Angle 

(degree) 

SR -0.15 76.28 

NE +15.08 86.25 

Case 2 

 Table C2. Sun Angle data: at Sunrise and NE. 

Sun Elevation Angle 

(degree) 

Azimuth Angle 

(degree) 

SR -0.20 76.65 

NE +11.47 83.99 

Case 3 

 Table C3. Sun Angle data: at Sunrise and NE. 

Sun Elevation Angle 

(degree) 

Azimuth Angle 

(degree) 

SR -0.36 77.37 

NE +14.56 86.72 

 

1 Algorithms based on Quality Assurance Handbook for Air Pollution Measurements Systems, vol. IV: Meteorological 

 Measurements (as Revised March 1995) document number EPA/600/R-94/038d. 
18

Acronyms 

ASL Atmospheric Surface Layer 

Delta-T The 35 m minus 2 m Temperature difference 

DLR Desert Lapse Rate Project 

LR Lapse Rate 

MDT Mountain Daylight Time 

Met Meteorology, meteorological 

MSL Mean Sea Level 

NE Neutral Event 

SL Surface Layer 

SR Sunrise 

SRL Sunrise, locally observed at the experiment site 

T-RH Temperature-Relative Humidity 

WSMR White Sands Missile Range