Frank J. Gouveia. Ron L.Baskett. This paper was prepared for submittal to the Nuclear Utility Meteorological Data Users Group Workshop (NUMUG)

Transcription

1 UCRL- JC PREPRNT COMPARSON OF DATA FROM CO-LOCATED SENSOR PACKAGES AND MPLCATONS FOR DSPERSON MODELNG: AN N STU CASE STUDY OF RUGGED VERSUS LOW-THRESHOLD ANEMOMETERS AND NATURAL-VERSUS FORCED-VENTLATON SOLAR SHELDS Frnk J. Gouvei Ron L.Bskett This pper ws prepred for submittl to the Nucler Utility Meteorologicl Dt Users Group Workshop (NUMUG) Sn Frncisco, Cliforni, April 25, 1996 April 1996 This is preprint of pper intended for publiction in journl or proceedings. Since chnges my be mde before publiction, this preprint is mde vilble with the understnding tht it will not be cited or reproduced without the 1 permission of the uthor. LL6421W vl. (396)

2 DSCLAMER This report ws prepred s n ccount of work sponsored by n gency of the United Sttes Government Neither the United Sttes Government nor ny gency thereof, nor ny of their employees, mke ny wrrnty, express or implied, or ssumesny legl libility or responsiiility for the cmrcy, completeness, or usefulness of ny informtion,pprtus, product, or process disdosed, or represents tht its use would not infringe privtely owned rights. Reference herein to ny specific commefiil product, process, or service by trde nme, trdemrk, mhcturer, or otherwise does not necessrily comtitute or imply its endorsement, remrmendtion,or fvoring by the United Sttes Governmentor ny gency thereof. The views nd opinions of uthors expressed herein do not D~C~SSBTiJystte or reflect those of the United Sttes Government or ny gency thereof.

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4 Comprison of dt from co-locted sensor pckges nd implictions for dispersion modeling: An in situ cse study of rugged versus low-threshold nemometers nd nturl- versus forced-ventiltion solr shields Frnk J. Gouvei nd Ron L. Bskett Helth & Ecologicl Assessment Division Lwrence Livermore Ntionl Lbortory Livermore, Cliforni Abstrct We compred 27 dys of 15-minute-verge dt from two sets of co-locted wind nd temperture sensors t 1- nd 4-m levels on tower t Lwrence Livermore Ntionl Lbortory. One nemometer set ws rugged nd the other ws more sensitive with lower threshold. At moderte winds (2<U<1 m/s) wind speed nd direction between the two sets of sensors were strongly correlted. At low winds (U<2 m/s), the two sets produced smll discrepncies due to different thresholds nd clibrtion methods for the wind speed sensors. Stbility clss (Modified Sigm Thet method) ws the sme for ech sensor pckge for 76% of the study period nd within one stbility clss for 94% of the time. We lso compred temperture dt from the nturlly spirted solr shields with dt from fn-spirted shields. The tendencies were expected nd quntified: lrge temperture differences when the wind speed ws low nd insoltion ws gret. Temperture difference ws greter thn lc bout 15% of the study period nd greter thn OSC bout 39% of the time. ntroduction Since the erly 198s, Lwrence Livermore Ntionl Lbortory (LLNL) in Livermore, Cliforni hs collected on-site meteorologicl dt for use in regultorydriven dispersion modeling nd for emergency prepredness nd response. A worksttion collects dt from the dul-purpose tower using softwre developed by the DOE Atmospheric Relese Advisory Cpbility (ARAC) t LLNL. Consequently, the originl sensors on the tower conformed to the ARAC network design which included rugged wind sensors tht only needed nnul clibrtion nd mintennce. The relible Hndr 54 dt logger nd durble sensors met these criteri lthough the meteorologicl sensors did not meet ll PSD (Prevention of Significnt Deteriortion) guidelines (EPA 198) nd further guidnce lter developed by DOE (1991). n response to recent By Are Air Qulity Mngement District nd DOE (1 991) recommendtions to monitor meteorologicl conditions with greter sensitivity, we instlled new set of sensors during October of We took dvntge of this opportunity to cquire simultneous dtbse from both sets of sensors. Previous field comprisons of meteorologicl sensors (Finkelstein 1986, Tnner 1996) hve shown tht wind tunnel experiments my not revel the true chrcter of wind vne s response

5 to nturl wind nd turbulence conditions. We designed our study to compre the dt from the two juxtposed sets of sensors nd ttempted to explin differences in the mesurements. n ddition, we explored the effect of these differences on dispersion clcultions by compring Psquill stbility clss computed using the Modified Sigm Thet method. We lso used the dtsets to compute the men composite downwind concentrtion profile in Gussin dispersion model. Description of field experiment ' Descriptions of the site nd tower LLNL is locted on the estem side of the Livermore Vlley, bout 3 miles est of Oklnd, Cliforni. The meteorologicl tower is locted ner the northwest comer of LLNL site with n elevtion of 174 m. The surfce topogrphy slopes up gently towrds the southest with grde of pproximtely 12 m verticlly in 1 km. The 4-m LLNL meteorologicl tower is locted where it is exposed to reltively open fetches for over 15 m in ll directions. The vegettion surrounding the tower consists mostly of nnul grsses. The surfce roughness is bout.15 m nd the zero-plne displcement is.5 cm (Chpmn & Gouvei, 1988). The lrgest nerby feture is north by south line of euclyptus trees bout 15 m to the est. A housing development is bout 25 m to the west, commercil buildings re locted 3 m to the north. The closest substntil structure towrds the south is pproximtely 5 m wy from the tower. The sensors re fixed to crossrms tht re on 2-m long booms extending off the west side of the tower t 1 nd 4 m bove the ground. The booms re rised nd lowered by mens of mnul-crnk elevtor. For this study, both the Hndr nd Met One sensor wind sets were mounted on the booms. The Hndr crossrm ws oriented north/south with the wind vne on the north end. The Met One crossrm ws ttched to the Hndr crossrm with the wind vne on the west end. Vribles mesured by both systems t both levels included horizontl wind speed nd direction, stndrd devition of wind direction (oe), nd temperture. Additionlly, the Met One system included temperture t 2 m nd solr rdition sensor. Mintennce is performed ccording to EPA guidnce (EPA 1987 nd 199). However, delys in instlling the Met One system forced us to postpone the regulr clibrtion of the Hndr sensors. This deferred mintennce my hve influenced the response of the Hndr 431A vne nd 43A cups. Toque mesurements on the wind sensors re pending s well s the clibrtion of the thermistors. Dt cquisition We connected the Hndr nd Met One systems to seprte but identicl Hndr 54 dt loggers running similr cquisition progrms synchronized to the sme clock. Ech 54 logger polled the instruments every second nd 15-minute verges were stored. The dt were trnsferred periodiclly vi modem to Sun worksttion. Both systems clculted oe by the sme lgorithm following Ymrtino (1 984). Sensors Physicl description The following specifictions of the Hndr nd Met One sensors re from the respective mnufcturer's literture. Tble 1 summrizes the sensors used in this study. 2

6 Anemometry Both the Hndr 431A nd Met One 2C wind direction sensors re vnes using precision potentiometers. The hed or counter blnce of the Hndr vne hs lrger surfce re thn the Met One vne. The Hndr 43A nd Met One 1 OC wind speed sensors re 3-cup design. The 43A uses rotting mgnetic field in proximity to Hll Effect device to produce pulse output directly proportionl to wind speed. The 1 OC uses slotted chopper disk to produce pulsed output tht is converted to voltge proportionl to wind speed. Tble 2 presents the strting threshold, distnce constnt nd dmping rtio for ll wind sensors. The dmping rtio, g, for the Hndr 431A vne ws computed with the formultion from Wng (1 979), where r is the vne rm length nd D is the distnce constnt. The Hndr 431A vne meets PSD guidelines (EPA 198) for strting threshold (.5 m/s) nd distnce constnt ( 5 m) but is just outside the PSD rnge for dmping rtio (.4 -.6). The Met One 2C vne meets ll PSD guidelines. Temperture The Hndr nd Met One systems both utilize the YS 446 single-bed thermistor. The stndrd lookup tbles locted in the Hndr 54 firmwre converted thermistor resistnce to temperture units. This thermistor shows n bsolute ccurcy off.5 OC of stndrd. Solr shields The solr shield for the two Hndr thermistors is the model 442A Convection-Aspirted Shield. This shield tkes dvntge of the nturl flow of ir for ventiltion. The Met One system includes the 768 Rdition Shield. This shield includes motor with fn - tht provides constnt flow of ir pst the temperture nd humidity sensors. This shield uses n AC fn to produce flow of 2.5 m/s in the inner smple tube nd 5 m/s in the ir spce between the nested tubes. Tble 1 - Sensor types nd model numbers used in this study. Vrible Type Hndr Met One Wind direction Vne 431A 2c Wind speed 3-cup 43A 1 oc Air temperture Thermistor YS 446 YS 446 Solr shield Nturl 442A -- Solr shield Forced nsoltion Licor Tble 2 - Specifictions of the nemometers nd vnes. Strting Distnce Dmping Model threshold constnt rtio 437A vne.5 m/s 5. m.2* 43A cups C vne.3 <1.o OlOC cups >.4* - * Vlues computed from Eq. 1. 3

7 Rdiometer We mesure incoming solr rdition with Licor-type Met One model 96-1 Solr Rdition Sensor connected electroniclly to the Met One system. Study period Mutul dt collection strted on 11 October 1995 nd continued to 3 November An interruption in the dt collection creted gp in the comprison dt during the first two weeks of November. This interruption resulted in two comprison periods, the first with 1512 fifteenminute records nd the second with 19 records. Preliminry nlysis of both periods indicted no significnt differences in the dt sets. Therefore, ll subsequent nlysis combined dt from both periods. The wind rose for the study period (Figure 1) shows tht 1 of the 16 compss directions hve frequency over 5%. The dt for this wind rose ws tken from the 1-m level of the Met One system. The wether during the study period ws typicl for utumn t LLNL. The verge nnul wind speed t the site is 2.3 m/s (Gouvei nd Chpmn 1989). The fll study period reflects reltively clm period of the yer. The verge wind speed for the study period s mesured by the Met One sensors ws 1.8 m/s t the 1-m level. The verge wind speed in the predominte wind directions ws somewht higher thn the ll-direction verge. For winds from the NE the verge ws 2.5 m/s t the 1-m level, from the SW the verge ws 2.3 m/s. There ws no mesurble precipittion lthough fog ws observed severl times in the morning hours. Comprisons between sensor dt sets _--.. Wind direction We compre wind direction dt when the wind speed ws greter thn 2 m/s. A seprte nlysis of low wind speed cses is discussed in following section. Figures 2 nd 3 show the highly correlted wind direction dt s mesured by the two sensors t 1 nd 4 m. Figures 4 nd 5 plot the difference between the wind vnes ginst the Met One vne position. This sme wvy pttern ws described in Lockhrt (1989). There seems to be consistent 3' devition between the Met One nd the Hndr vnes t the 1-m level which is due to lignment difference. Some bis my be due to non-linerity of the potentiometers, out-of-round, or signl conditioning errors lthough these errors re typiclly not greter thn k3o (EPA 199). Most of the wind vne difference dt is within this rnge. Wind Speed The wind speed s mesured by the two systems shows very good correltion s shown in figures 6 nd 7, especilly t speeds greter thn 2 m/s. The smll difference t the low winds my be due to different mnufcturer's recommended conversion from shft rottion to m/s. Averge wind speed mesured t 1 m ws 1.8 m/s for the Met One system nd 1.5 m/s for the Hndr system. At the 4-m level the verge wind speed for the Met One nd Hndr systems ws 2.5 nd 2.1 m/s, respectively. Sigm Thet The lrgest difference between mesured quntities is found in the dt. Figures 8 nd 9 show s mesured by the Met One versus oe from the HANDAR system for the 1 nd 4 m levels. We excluded the low winds (e 2 m/s) in these figures due the lrge differences of oe in this rnge. The Hndr's smller dmping rtio cn explin why the Hndr oe ws sometimes lrger thn the Met One oo. EPA (199) sttes tht vnes with smller dmping rtio, such s the 431A, will report more vribility from the sme turbulent flow thn vne with lrger dmping 4

8 rtio. Tble 3 displys the percent occurrence of selected rnges of the difference in oe redings. Note the consistent vlues between the two levels in this tble when the wind speed is limited. Temperture Ambient ir temperture s mesured by both systems follows predictble pttern s described in Tnner (1996). Figure 1 shows the comprison between the temperture mesurements t 1 m. The 4-m temperture shows the sme pttern s the 1-m dt lthough for slightly nrrower rnge of temperture. Redily pprent in this plot is the tilt of the dt points for the nturl ventilted solr shield towrds higher dytime tempertures nd lower nighttime tempertures. Figure 11 shows the temperture difference between the systems plotted with wind speed for the 1-m level (gin, the 4-m grph ws omitted for redundncy). Figure 12 shows the sme temperture difference plotted ginst solr rdition. The lrgest vlues of temperture difference occur when strong insoltion corresponds with wek winds. An ttempt ws mde to crete simple djustment to the temperture dt from the nturlly ventilted shield. We mde function bsed on liner regression, AT =.143* U -.386* R, where U is the wind speed in m/s nd R is incoming solr rdition in w/m2. The constnt term ws close to zero nd ignored. The coefficients revel tht, for our site nd this dt set, solr rdition cuses more temperture error thn the wind speed due to the unventilted shields. After pplying the bove djustment to the Hndr temperture dt the stndrd error between the Met One nd Hndr systems ws reduced from bout.9 to.6oc. Figure 13 shows the djusted nturlly spirted temperture nd the fn-spirted temperture dt. More improvement could be chieved with knowledge of the solr rdition incident on the sides of the nturlly spirted shields. Computed vribles Stbility by MST We computed stbility, s clssified by Psquill stbility ctegories, using the Modified oe method (.k.. lterl turbulence nd wind speed method) described in EPA (1987). This method uses oefor n initil estimte of Psquill clss which is djusted with wind speed nd time of dy. The computtion is mde seprtely for every 15-minute verging period, ech level (1 nd 4 m), nd ech system. No ttempt ws mde to smooth the stbility clss with time. Tbles 4 nd 5 show the percent occurrence of Psquill ctegory for the two systems for the 1- nd 4-m - Tble 3 Percent occurrence of the difference of oebetween the Hndr nd Met One systems for the 1- nd 4-m levels. All wind speeds WSlo 2 2 mls Rnge of difference between oevlues 1 m 4 m 1 m 4 m f f f f f f f

9 levels, respectively. These nlysis show tht the Psquill ctegory is lmost lwys the sme between the systems. n fct, s Tble 6 shows, ech system produces the sme stbility ctegory 75 to 8% of the time. The systems re within one clss bout 95% of the time. Period of low winds We identified 16-hour period of winds less thn 2 m/s beginning in the evening of 19 October for dditionl study. Figure 14 shows time series of wind speed for ech system nd the difference of wind direction between the two systems. The pproximtely.3 m/s seprtion in the wind speed trces re result of different methods converting cup rottion to speed s described bove. At bout 1 A.M. nd continuing for lmost 5 hours, the 43A nemometer reported. m/s while the lower threshold OlOC detected smll pulses s much s.6 m/s for few 15-minute periods. Figure 15 shows time series of the wind direction from both the lowthreshold nd rugged wind vnes. The vnes trck very well when the wind ws between from.5 nd 2. m/s, but then devite when the winds fll below.5 m/s (s mesured by the OlOC). Tble 4 - Distribution of the 2587 reliztions of P-G stbility clss s computed for the Hndr nd Met One systems t the 1 Om level. Vlues re presented in percent. Hndr MetOne A B C D E F All A o B C - 1.l D E F All Tble 5 - Sme s Tble 4 but for the 4-m level. Hndr Met One A B C D E F All A B C D.6 21.o E F A Tble 6 - Percent difference in stbility clss (Met One minus Hndr) for both levels _(A4... F=6). Difference in Clss 1 m 4 m

10 Wind rose sttistics Wind roses were mde for the 1-m level nd re presented s Figures 1 nd 16, for the Met One nd Hndr systems, respectively. The 4-m dt show the sme ptterns nd were not included here for brevity. The wind rose sttistics summrized in Tbles 7 nd 8 re described below. Tble 7 is histogrm of wind direction for ll wind vnes. Wind speeds less thn.5 m/s re considered below threshold for both systems nd wind direction mesurement is unrelible. At these low winds the ctul wind direction is ignored nd the wind is distributed evenly mong ll wind directions. The difference in frequency between systems t the sme level is never greter thn three percent. Frequency distribution of wind speed for ll nemometers re presented in Tble 8. t is gin evident in this tble tht the OlOC wind speed sensors report lrger vlues thn the 43A sensors. This result is the most compelling reson for switching to the low-threshold nemometer nd vne. Pst nnul wind roses for LLNL (Gouvei nd Chpmn 1989, nd Hrrch, et t. 1994) feture frequency of winds less thn.5 m/s of bout 14% using the Hndr sensors. t is expected tht, with the lower threshold instruments, the frequency of winds in this lowest clss will be less thn 5% in the nnul wind rose. Tble 7 - Percent of wind direction for both systems t both levels. Wind speeds less thn.5 m/s re distributed evenly mong ll wind directions. Direction 1 m 4 m from Met One Hndr Met One Hndr NNE NE ENE E ESE SE SSE S ssw sw wsw W WNW NW NNW N Tble 8 - Percent of.wind speed rnges for both systems nd both levels. System Level (m).-.4 Wind Speed clss (m/s) Met One Hndr Met One Hndr

11 Dispersion model The regultory model, CAP88-PC (EPA 1992), ws run to investigte the impliction of using meteorologicl dt from the two systems. CAP88-PC is n EPA-pproved ir-dispersion nd dose-ssessment model. The current study just looks t the ir dispersion cpbility of CAP88- PC. The model estimtes downwind concentrtions with Gussin dispersion lgorithm. The meteorologicl dt must be processed into joint-frequency tbles of wind direction nd stbility clss s well s tbles of verge nd hrmonic verge wind speed. The model estimtes the concentrtions t receptors rrnged in polr coordintes with 16 rdils nd 19 distnce rings from 1 to 1 m. This scheme yielded totl of 34 individul receptors. The concentrtion t given receptor is ffected by the frequency of wind in tht direction s well s the frequency of stbility clss nd the verge wind speed. A fictious but plusible source ws entered into the model. The source ws 3-m high stck with exit velocity of bout 8. m/s nd dimeter of 1.2 m. The effluent ws gseous, neutrlly buoynt nd hd no settling. A unit source strength ws used to produce reltive concentrtions. All prmeters for both runs were the sme except for the source of the meteorologicl dt. Figure 17 compres the verge reltive concentrtion of the two model runs s function of downwind distnce between.1 nd 1.O km. The verge reltive ir concentrtion is n verge of the reltive concentrtions from ll 16 directions t prticulr distnce from the source. The reltive concentrtions re 1-2% lower for the CAP88-PC run using the Met One meteorologicl dt. This my be due in prt to the higher wind speeds of this dt set. The higher winds increse the dilution of the plume nd llow for less plume rise of the momentumdriven effluent. The higher winds tend to move the stbility clss towrds neutrl, but this my be prtilly offset by smller vlues of oe from the Met One vne. The reltive concentrtions for 185 of the 34 receptors (bout 6%) ws lower for the model run using Met One dt. Conclusions e Housing thermistors in fn-spirted shields significntly improves the ccurcy of temperture mesurements over the nturlly spirted shields. More nlysis is necessry to determine if temperture mesurements mde with thermistors in fn-spirted shields is dequte for AT/k estimtion. mprovement in the ccurcy of ir temperture mesurements mde in nturlly spirted solr shields cn be chieved by compensting for wind nd solr rdition. = 3 The rugged, higher threshold wind sensors my be pproprite for meteorologicl monitoring in windy or hostile environments. More sensitive wind sensors produce two differences: More informtion bout wind t very low wind speeds. Smller e due to higher dmping. e Estimtes of dispersion will be ffected by slightly higher wind speeds mesured by the Met One wind sensors. The slightly higher wind speeds will decrese downwind ir concentrtions due to incresed dilution of the plume.

12 Acknowledgments The uthors would like to thnk the following individuls who were instrumentl in the completion of this work. Gry Ber nd Jon Welch must be recognized for their expert technicl support when instlling the new monitoring system. Brent Bowen's efforts re pprecited for his ssistnce with the interprettion of the results. Vluble nd timely help cme from Clyde Dvis t Hndr nd Dennis Recl nd Ron Rlston t Met One. Work performed under the uspices of the U.S. Deprtment of Energy t Lwrence Livermore Ntionl Lbortory under contrct W-745-Eng-48. References Chpmn, K.R. nd F.J. Gouvei, 1988: Wind Flow Study: July 1987 nd November-December 1987, UCD-2136, Lwrence Livermore Ntionl Lbortory, Livermore, CA. DOE, 1991 : Environmentl Regultory Guide for Rdiologicl Effluent Monitoring nd Environmentl Surveillnce, DOE/EH-O173T, U.S. Deprtment of Energy, Assistnt Secretry for Environment, Sfety nd Helth, Wshington, D.C.. EPA, 198: Ambient Monitoring Guidelines for Prevention of Significnt Deteriortion (PSD), EPA-45/4-8-12, U.S. Environmentl Protection Agency, Office of Air Qulity, Reserch Tringle Prk, NC. EPA, 1987: On-Site Meteorologicl Progrm Guidnce for Regultory Modeling Applictions, EPA-45/ , U.S. Environmentl Protection Agency, Office of Air Qulity, Reserch Tringle Prk, NC. EPA, 199: Qulity Assurnce Hndbook for Air Pollution Mesurement Systems, Volume V --- Meteorologicl Mesurements, EPA-6/4-9-3, U.S. Environmentl Protection Agency, Office of Reserch nd Development, Reserch Tringle Prk, NC. EPA, 1992: User's guide for CAP88-PC, Version 1, , U.S. Environmentl Protection Agency, Office of Rdition Progrms, Ls Vegs, NV. Finkelstein, P.L., J.C. Kiml, J.E. Gynor, M.E. Grves, nd T.J. Lockhrt, 1986: Comprison of wind monitoring systems: Prt : n situ sensors, J. of Atmos. nd Ocenic Techno/., 3, Gouvei, F.J. nd K.R. Chpmn, 1989: Climtology of Lwrence Livermore Ntionl Lbortory, UCD-21686, Lwrence Livermore Ntionl Lbortory, Livermore, CA. Hrrch, R.J., et l., 1994: Environmentl Report 1994, UCRL , Lwrence Livennore Ntionl Lbortory, Livermore, CA. Lockhrt, T.J., 1989: Accurcy of the Collocted Trnsfer Stndrd Method for Wind nstrument Auditing, J. of Atmos. nd Ocenic Techno/., 6, Tnner, B.D., E. Switek, nd C. Mughn, 1996: Field comprisons of nturlly ventilted nd spirted rdition shields for wether sttion ir temperture mesurements, Proceedings from the 22nd Conf. on Agriculturl & Forest Meteorology with Symposium on Fire & Forest Meteorology, Americn Meteorologicl Society, Boston, Mss.. Wng, J.Y., nd C.M.M. Felton, 1979: nstruments for Physicl Environmentl Mesurements, Milieu nformtion Service, nc. Ymttino, R.J., 1984: A comprison of severl 'Single-pss" Estimtors of the Stndrd Devition of Wind Direction, J. Climte nd Applied Meteorology, 23,

13 N Sensor Comprison t LLNL Study Period: Oct & Nov 1995 Met One System -- 1 m - E Wind Speed ( m/s ) >=6 Clms: 8.9% S Figure 1. Wind rose for the study period. Wind dt ws tken from the Met One system t the 1-m level. Figure 16 is similr wind rose for the Hndr system.

14 Wind Direction t 1 m 27 1y: 225 z Met One Figure 2. Comprison of wind direction redings for wind speeds 2. m/s or greter from the 1-rn level OL ws >= 2. m/s N = C Met One Figure 3. Sme s Figure but for the 4-m level.

15 1 OL z Wind direction difference t 1 m -HHH Qwc H: -.whcy)(w * Mu.H. -t w *tymcmc) il) *tn i c * *P 4 -n.-hh- * * * * * * tw * *- ws >= 2. m/s N= J Met One Wind Direction Figure 4. Difference in wind direction redings plotted ginst the wind direction from the Met One for wind speeds 2. m/s or greter t the 1-m level. OL 4 z c. r" 1 1 * 5- *ch - - * *** Cc* ** -uum.m i- --, * * * -Hcc* * * *HHc *-w ': --, - n. * w *, -* u -t nttt *** * * n Wi -5 - *- * : Wind Direction Difference t 4 m *. t -1 1 ws >= 2. m/s N = Figure 5. Sme s Figure 4 but for the 4-m level. Met One Wind Direction

16 1 9 Wind Speed t 1 rn 8 h u) z 7 U d p L 6 z 5 HANOAR = OG'MetOne Met One (m/s) Figure 6. Comprison of wind speed redings from the 1-m level. h u) Y 'E 7: d cl Met One (m/s) Figure 7. Sme s Figure 6 but for the 4-m level.

17 8 7 6 Sigm Thet (degrees) t 1 m ws >= 2. mls Met One Figure 8. Comprison of from the 1-m level. Sigm Thet (degrees) t 4 m ws >= 2. mls CE n z Figure 9. Sme s Figure 8 but for the 4-m level. Met One

18 3 25 OL z C J Met One Figure 1. Comprison of temperture from the 1-m level. Speed vs. Temp. Diff. t 1 m c s p $ Wind Speed (m/s) Figure 1 1. Difference in temperture from the 1-m level plotted ginst Met One wind speed.

19 n 9. 2 i Solr versus Temperture Difference t 1 m 1 E -1 n Z r Q) c r" w * ncoming Solr (w/m2) Figure 12. Difference in temperture from the 1-m level ginst incoming solr rdition. 3 Temperture (C) t 1 m - OL n Z d Met One Figure 13. Met One temperture versus Hndr temperture djusted for wind speed nd solr rdition.

20 Hour (PS) ' Met One-D 1 - ADir ' -,*,#,'...e,. 1, Figure 14. Time series of wind speeds t 1 rn during 16-hour period (1 9-2 Od) of winds e2 m/s. Hour (PST) r c g 18 f Met One 45 ', 1, Figure 15. Wind direction for the Hndr nd Met One systems during the sme period s Figure 14.

21 N Sensor Comprison t LLNL Study Period: Oct & Nov 1995 Hndr System -- 1 m W E Wind Speed ( m/s ) >=6 Clms: 31.7% S Figure 16. Wind rose for the study period. Wind dt ws tken from the Hndr system t the lh level. 4. -t Distnce from Stck (m) Figure 17. Averge reltive concentrtions plotted ginst distnce from the stck s modeled using CAP88-PC.