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{{#Wiki_filter:Robert Palla -Paper Abstract Page From: Robert Palla To: Natasha Greene Date: 04/24/2007 2:52:54 PM  
{{#Wiki_filter:Robert Palla - Paper Abstract                                                                                           Page *I From:             Robert Palla To:               Natasha Greene Date:             04/24/2007 2:52:54 PM


==Subject:==
==Subject:==
Paper Abstract I came across this, as well as some papers (actually just abstracts) by Jen Thorpe and by Samuel Miller.
Paper Abstract I came across this, as well as some papers (actually just abstracts) by Jen Thorpe and by Samuel Miller.
1ýc:vemp\uvv)uuuui.
 
i ivw F'age 1 ql c:\temp\~VV}UUUU].i lvii-' I-'age 1 Mail Envelope Properties (462E5206.BI2
1ýc:vemp\uvv)uuuui. i ivw                                                                             F'age 1 ql c:\temp\~VV}UUUU].i lvii-'                                                                           I-'age 1 Mail Envelope Properties   (462E5206.BI2 : 18 : 10412)
: 18 : 10412)


==Subject:==
==Subject:==
Creation Date From: Created By: Paper Abstract 04/24/2007 2:52:54 PM Robert Palla RLP3 @nrc.,oov Recipients nrc.gov OWGWPO02.HQGWDO01 PM NAG (Natasha Greene)PM Post Office OWGWPO02.HQGWDO01 Action Delivered Opened Date & Time 04/24/2007 2:53:00 04/24/2007 2:59:04 Delivered Route 04/24/2007 2:53:00 PM Date & Time 04/24/2007 2:52:54 PM 04/24/2007 2:50:01 PM nrc.gov Files MESSAGE 39276.pdf Options Auto Delete: Expiration Date: Notify Recipients:
Paper Abstract Creation Date         04/24/2007 2:52:54 PM From:                Robert Palla Created By:          RLP3 @nrc.,oov Recipients                                       Action              Date & Time nrc.gov OWGWPO02.HQGWDO01                             Delivered           04/24/2007 2:53:00 PM NAG (Natasha Greene)                          Opened              04/24/2007 2:59:04 PM Post Office                                      Delivered         Route OWGWPO02.HQGWDO01                              04/24/2007 2:53:00 PM     nrc.gov Files                          Size              Date & Time MESSAGE                      414                04/24/2007 2:52:54 PM 39276.pdf                    542552            04/24/2007 2:50:01 PM Options Auto Delete:                 No Expiration Date:             None Notify Recipients:           Yes Priority:                     Standard ReplyRequested:               No Return Notification:         None Concealed  
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==Subject:==
==Subject:==
Security: To Be Delivered:
No Security:                     Standard To Be Delivered:             Immediate Status Tracking:             Delivered & Opened
Status Tracking: Size 414 542552 No None Yes Standard No None No Standard Immediate Delivered  
 
& Opened 2.3 NUMERICAL STUDY OF THE INFLUENCES ON POLLUTANT TRANSPORT DUE TO MULTIPLE CONVERGENCE ZONES IN THE SEA BREEZES OF CAPE COD AND SOUTHEASTERN MASSACHUSETTS Nelson L. Seaman , Aijun Deng', Glenn K. Hunter', Bruce A. Egan 2 , and Annette M. Gibbs', 1The Pennsylvania State University Department of Meteorology, University Park, PA 2 Egan Environmental, Inc.Beverly, MA 1. INTRODUCTION In New England (NE) it is common for power plants and other large emission sources to be concentrated along the coastline, where prevailing mid-latitude westerly winds can advect effluents over the ocean. Of course, mesoscale circulations, especially the sea breeze, can dominate coastal winds when the large-scale flow is weak and land-ocean thermal contrast is large.However, irregular coastlines (bays and peninsulas) and topography lead to multiple thermally driven circulations that can interact and make it difficult to estimate exposure to harmful airborne species.Therefore, a numerical investigation has been conducted to better understand the influences on pollutant transport and diffusion due to interactions between local and mesoscale sea-breezes over Cape Cod and southeast MA. The study involves a mesoscale meteorological model (the PSU/NCAR MM5v3.4), a trajectory calculator (TRAJEC) and three plume dispersion models (CALPUFF, ISC3ST, and SCIPUFF).
2.3       NUMERICAL STUDY OF THE INFLUENCES ON POLLUTANT TRANSPORT DUE TO MULTIPLE CONVERGENCE ZONES IN THE SEA BREEZES OF CAPE COD AND SOUTHEASTERN MASSACHUSETTS Nelson L. Seaman   , Aijun Deng', Glenn K. Hunter', Bruce A. Egan 2 , and Annette M. Gibbs',
Transport and diffusion of plumes from two power plants (elevated sources), a highway, and Otis AFB (surface sources) were calculated.
1The   Pennsylvania State University Department of Meteorology, University Park, PA 2
A companion paper in this volume describes the dispersion modeling results (Egan et al. 2002). This paper focuses on the meteorological modeling and trajectory calculations.
Egan Environmental, Inc.
: 2. MODEL DESCRIPTION, METHODOLOGY AND CASE DESCRIPTION The MM5v3.3 is a 3-D non-hydrostatic full-physics meteorological model with a terrain-following vertical coordinate (Grell et al. 1994). For this study, the model was configured with the Dudhia radiation and explicit moisture schemes, and a 1.5-order TKE turbulence scheme. Four nested domains were used with meshes of 36, 12, 4, and 1.33 km (Figure 1). All domains had 50 layers (30 below 1560 m), with the first level at -12 m AGL. The 4-km grid over southern NE had 151 X 151 points and the 1.33-km grid over Cape Cod had 115 X 115 points. The Kain-Fritsch deep convection scheme was used, but only on the 36- and 12-km domains. Four-dimensional data assimilation (FDDA)was applied on the 36- and 12-km domains via analysis Corresponding author: N.L. Seaman, Penn State Univ., Dept. of Meteorology, University Park, PA, 16802.Ph.: 814-863-1583, Email: seaman@ems.psu.edu nudging to reduce large-scale errors that could affect the local sea-breeze development.
Beverly, MA
NOAA EDAS analyses were used for the model's initial and boundary conditions and for FDDA. Three 48-h cases with weak synoptic-scale forcing were chosen from the summer of 2000: 1-2 July, 5-6 July, and 21-22 August. All three were post cold-frontal cases with weakening large-scale winds and a large land-sea thermal contrast that led to a sea breeze on one or both days of the episodes.3. RESULTS Here, we concentrate on results on the 1.33-km grid at 1800 UTC, 1 July. Manual analysis shows a thermal low over the interior of MA with a converging regional sea-breeze front (Fig. 2). The MM5 reproduces this front, plus several convergence zones due to local sea breezes over Cape Cod (Fig. 3). Figure 4 shows 6-h trajectories initiated from four emissions sources and ending at this same time. The trajectories show strong influences due- to both the regional and local sea breezes. Table 1 gives a summary of statistical results for all three cases in three layers of the atmosphere.
: 1. INTRODUCTION                                              nudging to reduce large-scale errors that could affect the local sea-breeze development. NOAA EDAS In New England (NE) it is common for power plants and          analyses were used for the model's initial and boundary other large emission sources to be concentrated along          conditions and for FDDA. Three 48-h cases with weak the coastline, where prevailing mid-latitude westerly          synoptic-scale forcing were chosen from the summer of winds can advect effluents over the ocean. Of course,          2000: 1-2 July, 5-6 July, and 21-22 August. All three mesoscale circulations, especially the sea breeze, can          were post cold-frontal cases with weakening large-scale dominate coastal winds when the large-scale flow is            winds and a large land-sea thermal contrast that led to weak and land-ocean thermal contrast is large.                  a sea breeze on one or both days of the episodes.
: 4.  
However, irregular coastlines (bays and peninsulas) and topography lead to multiple thermally driven                3. RESULTS circulations that can interact and make it difficult to estimate exposure to harmful airborne species.                  Here, we concentrate on results on the 1.33-km grid at Therefore, a numerical investigation has been                  1800 UTC, 1 July. Manual analysis shows a thermal conducted to better understand the influences on                low over the interior of MA with a converging regional pollutant transport and diffusion due to interactions          sea-breeze front (Fig. 2). The MM5 reproduces this between local and mesoscale sea-breezes over Cape              front, plus several convergence zones due to local sea Cod and southeast MA.          The study involves a            breezes over Cape Cod (Fig. 3). Figure 4 shows 6-h mesoscale meteorological model (the PSU/NCAR                    trajectories initiated from four emissions sources and MM5v3.4), a trajectory calculator (TRAJEC) and three            ending at this same time. The trajectories show strong plume dispersion models (CALPUFF, ISC3ST, and                  influences due- to both the regional and local sea SCIPUFF). Transport and diffusion of plumes from two            breezes. Table 1 gives a summary of statistical results power plants (elevated sources), a highway, and Otis            for all three cases in three layers of the atmosphere.
AFB (surface sources) were calculated. A companion paper in this volume describes the dispersion modeling          4.  


==SUMMARY==
==SUMMARY==
The MM5 produces realistic mesoscale structures on a 1.33 km grid, in terms of both the regional sea breeze and statistical agreement with regional data. The fine-grid model also produces local sea breezes over Cape Cod that cannot be resolved by standard observations.
 
: 5. ACKNOWLDGEMENTS Support for this study was provided by MA Dept.of Public Health through Contract No. RFR File No. 1J2.6. REFERENCES Egan, B.A., N. Seaman, R. Yamartino, and J. Purdum, 2002: Modeling pollutant dispersion from elevated and ground level sources affected by sea-breeze circulations produced by Cape Cod and its sur-roundings.
results (Egan et al. 2002). This paper focuses on the meteorological modeling and trajectory calculations.            The MM5 produces realistic mesoscale structures on a 1.33 km grid, in terms of both the regional sea breeze
AMS 12th Joint Conf. on the Appl. Of Air Poll. Meteor. with A&WMA. Norfolk, VA, 20-24 May, 2 pp.Grell, G.A., J. Dudhia and D.R. Stauffer, 1994: A description of the fifth-generation Penn State/NCAR Mesoscale Model (MM5). NCAR Technical Note NCARITN-398+STR, 121 pp.
: 2. MODEL DESCRIPTION, METHODOLOGY AND                        and statistical agreement with regional data. The fine-CASE DESCRIPTION                                          grid model also produces local sea breezes over Cape Cod that cannot be resolved by standard observations.
S1Gl -0.90 0ARB Uk /.. 2000-09-0119,59.55 2N10-07-0I.0I  
The MM5v3.3 is a 3-D non-hydrostatic full-physics meteorological model with a terrain-following vertical          5. ACKNOWLDGEMENTS coordinate (Grell et al. 1994). For this study, the model was configured with the Dudhia radiation and explicit                  Support for this study was provided by MA Dept.
.1.011E 5900T,-Figure 1. Location of 36, 12, 4 and 1.33-km nested domains for the MM5 configuration over Cape Cod.CAPECODI -DOMAIN 4 (I,33KM)Figure 3. MM5 surface-layer wind (ms-') on the 1.33-km domain in Case 1 valid at 1800 UTC, 1 July 2000 (+18 h). Full barb is 10 ms>'. Contour interval is 2 ms-1'.Heavy dashed line with wedges represents sea-breeze front. Dashed lines indicate convergence zones.CAPECOD 00.lO. 1.33k0 12-18h'Tr-j-.t -. r. _I ....d .t 12.0 ho...Term-hated  
moisture schemes, and a 1.5-order TKE turbulence                of Public Health through Contract No. RFR File No. 1J2.
*t 1.0 hu.r-Figure 2 Manual analysis of sea-level pressure (mb)over the area of the 1.33-km MM5 domain for Case 1 at 1800 UTC, 1 July 2000. Isobar interval is 1 mb.Table 1. Averaged MM5 statistics for three cases of the Cape Cod sea breeze. MidTrop is 1000-5000 m, PBL is 45-1000 m, SfcLayer is 12 m AGL.Variable RMS MnAbs Mean % Within Layer Err Err Err Criteria Speed (ms-') Cr=2.0 ms-_MidTrop 2.36 2.03 +0.42 60.3 PBL 2.78 2.34 +0.88 49.7 SfcLayer 1.55 1.30 -0.03 78.9 Direct'n (deg) Cr=20.0deq MidTrop 18.8 16.7 -4.3 80.0 PBL 40.9 31.1 -6.7 52.9 SfcLayer 54.8 41.8 -5.7 41.3 Temp. (C) Cr=2.0 (C)MidTrop 0.99 0.82 +0.14 93.4 PBL 1.21 1.00 -0.51 88.2 SfcLayer 2.41 1.97 +0.16 61.2 Mix.Rat.(q/kq)
scheme. Four nested domains were used with meshes of 36, 12, 4, and 1.33 km (Figure 1). All domains had          6. REFERENCES 50 layers (30 below 1560 m), with the first level at -12 m AGL. The 4-km grid over southern NE had 151 X                Egan, B.A., N. Seaman, R. Yamartino, and J. Purdum, 151 points and the 1.33-km grid over Cape Cod had                      2002: Modeling pollutant dispersion from elevated 115 X 115 points. The Kain-Fritsch deep convection                    and ground level sources affected by sea-breeze scheme was used, but only on the 36- and 12-km                        circulations produced by Cape Cod and its sur-domains. Four-dimensional data assimilation (FDDA)                    roundings. AMS 12th Joint Conf. on the Appl. Of was applied on the 36- and 12-km domains via analysis                  Air Poll. Meteor. with A&WMA. Norfolk, VA, 20-24 May, 2 pp.
Cr=l (q/kq)MidTrop 0.97 0.80 -0.13 63.4 PBL 1.38 1.16 -0.25 55.2 SfcLayer 2.46 2.46 +0.25 33.3 SLvlPrs (mb) Cr=2.5 mb 0.69 0.62 +0.39 100.0 Figure 4. Six-hour TRAJEC forward trajectories based on MM5-simulated winds in Case 1. Release time is 1200 UTC, 1 July 2000 (+12 -18 h). Parcel 1 is Brayton Point plant. Parcel 2 is Canal plant. Parcel 3 is middle of highway segment. Parcel 4 is Otis AFB. Tick marks shown on trajectories give positions at 1-h intervals, or until the parcels exit the domain.}}
Corresponding author: N.L. Seaman, Penn State Univ.,          Grell, G.A., J. Dudhia and D.R. Stauffer, 1994: A Dept. of Meteorology, University Park, PA, 16802.                      description of the fifth-generation Penn State/NCAR Mesoscale Model (MM5). NCAR Ph.: 814-863-1583, Email: seaman@ems.psu.edu Technical Note NCARITN-398+STR, 121 pp.
 
S1Gl   -0.90   0ARBUk  /..       2000-09-0119,59.55 2N10-07-0I.0I . 1.011E 5900T,-
Figure 1. Location of 36, 12, 4 and 1.33-km nested domains for the MM5 configuration over Cape Cod.
CAPECODI
                                                                                                      - DOMAIN 4 (I,33KM)
Figure 3. MM5 surface-layer wind (ms-') on the 1.33-km domain in Case 1 valid at 1800 UTC, 1 July 2000
(+18 h). Full barb is 10 ms>'. Contour interval is 2 ms-1'.
Heavy dashed line with wedges represents sea-breeze front. Dashed lines indicate convergence zones.
CAPECOD00.lO.1.33k0 12-18h
                                                                      'Tr-j-.t -. r. _I .... d .t 12.0 ho...
Term-hated *t 1.0 hu.r-Figure 2 Manual analysis of sea-level pressure (mb) over the area of the 1.33-km MM5 domain for Case 1 at 1800 UTC, 1 July 2000. Isobar interval is 1 mb.
Table 1. Averaged MM5 statistics for three cases of the Cape Cod sea breeze. MidTrop is 1000-5000 m, PBL is 45-1000 m, SfcLayer is 12 m AGL.
Variable           RMS       MnAbs       Mean     % Within Layer             Err       Err       Err     Criteria Speed (ms-')                                       Cr=2.0 ms-_
MidTrop          2.36     2.03       +0.42     60.3 PBL               2.78     2.34       +0.88   49.7 SfcLayer         1.55       1.30       -0.03   78.9 Direct'n (deg)                                     Cr=20.0deq MidTrop           18.8       16.7       -4.3     80.0 PBL               40.9     31.1       -6.7     52.9       Figure 4. Six-hour TRAJEC forward trajectories based SfcLayer         54.8     41.8       -5.7     41.3 Temp. (C)                                         Cr=2.0 (C) on MM5-simulated winds in Case 1. Release time is MidTrop           0.99     0.82       +0.14   93.4         1200 UTC, 1 July 2000 (+12 - 18 h). Parcel 1 is PBL               1.21     1.00         -0.51   88.2         Brayton Point plant. Parcel 2 is Canal plant. Parcel 3 is SfcLayer         2.41     1.97       +0.16   61.2         middle of highway segment. Parcel 4 is Otis AFB. Tick Mix.Rat.(q/kq)                                     Cr=l (q/kq) marks shown on trajectories give positions at 1-h MidTrop           0.97     0.80       -0.13   63.4         intervals, or until the parcels exit the domain.
PBL               1.38       1.16       -0.25   55.2 SfcLayer         2.46     2.46       +0.25   33.3 SLvlPrs (mb)                                       Cr=2.5 mb 0.69     0.62       +0.39     100.0}}

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Robert Palla - Paper Abstract Page *I From: Robert Palla To: Natasha Greene Date: 04/24/2007 2:52:54 PM

Subject:

Paper Abstract I came across this, as well as some papers (actually just abstracts) by Jen Thorpe and by Samuel Miller.

1ýc:vemp\uvv)uuuui. i ivw F'age 1 ql c:\temp\~VV}UUUU].i lvii-' I-'age 1 Mail Envelope Properties (462E5206.BI2 : 18 : 10412)

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Paper Abstract Creation Date 04/24/2007 2:52:54 PM From: Robert Palla Created By: RLP3 @nrc.,oov Recipients Action Date & Time nrc.gov OWGWPO02.HQGWDO01 Delivered 04/24/2007 2:53:00 PM NAG (Natasha Greene) Opened 04/24/2007 2:59:04 PM Post Office Delivered Route OWGWPO02.HQGWDO01 04/24/2007 2:53:00 PM nrc.gov Files Size Date & Time MESSAGE 414 04/24/2007 2:52:54 PM 39276.pdf 542552 04/24/2007 2:50:01 PM Options Auto Delete: No Expiration Date: None Notify Recipients: Yes Priority: Standard ReplyRequested: No Return Notification: None Concealed

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2.3 NUMERICAL STUDY OF THE INFLUENCES ON POLLUTANT TRANSPORT DUE TO MULTIPLE CONVERGENCE ZONES IN THE SEA BREEZES OF CAPE COD AND SOUTHEASTERN MASSACHUSETTS Nelson L. Seaman , Aijun Deng', Glenn K. Hunter', Bruce A. Egan 2 , and Annette M. Gibbs',

1The Pennsylvania State University Department of Meteorology, University Park, PA 2

Egan Environmental, Inc.

Beverly, MA

1. INTRODUCTION nudging to reduce large-scale errors that could affect the local sea-breeze development. NOAA EDAS In New England (NE) it is common for power plants and analyses were used for the model's initial and boundary other large emission sources to be concentrated along conditions and for FDDA. Three 48-h cases with weak the coastline, where prevailing mid-latitude westerly synoptic-scale forcing were chosen from the summer of winds can advect effluents over the ocean. Of course, 2000: 1-2 July, 5-6 July, and 21-22 August. All three mesoscale circulations, especially the sea breeze, can were post cold-frontal cases with weakening large-scale dominate coastal winds when the large-scale flow is winds and a large land-sea thermal contrast that led to weak and land-ocean thermal contrast is large. a sea breeze on one or both days of the episodes.

However, irregular coastlines (bays and peninsulas) and topography lead to multiple thermally driven 3. RESULTS circulations that can interact and make it difficult to estimate exposure to harmful airborne species. Here, we concentrate on results on the 1.33-km grid at Therefore, a numerical investigation has been 1800 UTC, 1 July. Manual analysis shows a thermal conducted to better understand the influences on low over the interior of MA with a converging regional pollutant transport and diffusion due to interactions sea-breeze front (Fig. 2). The MM5 reproduces this between local and mesoscale sea-breezes over Cape front, plus several convergence zones due to local sea Cod and southeast MA. The study involves a breezes over Cape Cod (Fig. 3). Figure 4 shows 6-h mesoscale meteorological model (the PSU/NCAR trajectories initiated from four emissions sources and MM5v3.4), a trajectory calculator (TRAJEC) and three ending at this same time. The trajectories show strong plume dispersion models (CALPUFF, ISC3ST, and influences due- to both the regional and local sea SCIPUFF). Transport and diffusion of plumes from two breezes. Table 1 gives a summary of statistical results power plants (elevated sources), a highway, and Otis for all three cases in three layers of the atmosphere.

AFB (surface sources) were calculated. A companion paper in this volume describes the dispersion modeling 4.

SUMMARY

results (Egan et al. 2002). This paper focuses on the meteorological modeling and trajectory calculations. The MM5 produces realistic mesoscale structures on a 1.33 km grid, in terms of both the regional sea breeze

2. MODEL DESCRIPTION, METHODOLOGY AND and statistical agreement with regional data. The fine-CASE DESCRIPTION grid model also produces local sea breezes over Cape Cod that cannot be resolved by standard observations.

The MM5v3.3 is a 3-D non-hydrostatic full-physics meteorological model with a terrain-following vertical 5. ACKNOWLDGEMENTS coordinate (Grell et al. 1994). For this study, the model was configured with the Dudhia radiation and explicit Support for this study was provided by MA Dept.

moisture schemes, and a 1.5-order TKE turbulence of Public Health through Contract No. RFR File No. 1J2.

scheme. Four nested domains were used with meshes of 36, 12, 4, and 1.33 km (Figure 1). All domains had 6. REFERENCES 50 layers (30 below 1560 m), with the first level at -12 m AGL. The 4-km grid over southern NE had 151 X Egan, B.A., N. Seaman, R. Yamartino, and J. Purdum, 151 points and the 1.33-km grid over Cape Cod had 2002: Modeling pollutant dispersion from elevated 115 X 115 points. The Kain-Fritsch deep convection and ground level sources affected by sea-breeze scheme was used, but only on the 36- and 12-km circulations produced by Cape Cod and its sur-domains. Four-dimensional data assimilation (FDDA) roundings. AMS 12th Joint Conf. on the Appl. Of was applied on the 36- and 12-km domains via analysis Air Poll. Meteor. with A&WMA. Norfolk, VA, 20-24 May, 2 pp.

Corresponding author: N.L. Seaman, Penn State Univ., Grell, G.A., J. Dudhia and D.R. Stauffer, 1994: A Dept. of Meteorology, University Park, PA, 16802. description of the fifth-generation Penn State/NCAR Mesoscale Model (MM5). NCAR Ph.: 814-863-1583, Email: seaman@ems.psu.edu Technical Note NCARITN-398+STR, 121 pp.

S1Gl -0.90 0ARBUk /.. 2000-09-0119,59.55 2N10-07-0I.0I . 1.011E 5900T,-

Figure 1. Location of 36, 12, 4 and 1.33-km nested domains for the MM5 configuration over Cape Cod.

CAPECODI

- DOMAIN 4 (I,33KM)

Figure 3. MM5 surface-layer wind (ms-') on the 1.33-km domain in Case 1 valid at 1800 UTC, 1 July 2000

(+18 h). Full barb is 10 ms>'. Contour interval is 2 ms-1'.

Heavy dashed line with wedges represents sea-breeze front. Dashed lines indicate convergence zones.

CAPECOD00.lO.1.33k0 12-18h

'Tr-j-.t -. r. _I .... d .t 12.0 ho...

Term-hated *t 1.0 hu.r-Figure 2 Manual analysis of sea-level pressure (mb) over the area of the 1.33-km MM5 domain for Case 1 at 1800 UTC, 1 July 2000. Isobar interval is 1 mb.

Table 1. Averaged MM5 statistics for three cases of the Cape Cod sea breeze. MidTrop is 1000-5000 m, PBL is 45-1000 m, SfcLayer is 12 m AGL.

Variable RMS MnAbs Mean  % Within Layer Err Err Err Criteria Speed (ms-') Cr=2.0 ms-_

MidTrop 2.36 2.03 +0.42 60.3 PBL 2.78 2.34 +0.88 49.7 SfcLayer 1.55 1.30 -0.03 78.9 Direct'n (deg) Cr=20.0deq MidTrop 18.8 16.7 -4.3 80.0 PBL 40.9 31.1 -6.7 52.9 Figure 4. Six-hour TRAJEC forward trajectories based SfcLayer 54.8 41.8 -5.7 41.3 Temp. (C) Cr=2.0 (C) on MM5-simulated winds in Case 1. Release time is MidTrop 0.99 0.82 +0.14 93.4 1200 UTC, 1 July 2000 (+12 - 18 h). Parcel 1 is PBL 1.21 1.00 -0.51 88.2 Brayton Point plant. Parcel 2 is Canal plant. Parcel 3 is SfcLayer 2.41 1.97 +0.16 61.2 middle of highway segment. Parcel 4 is Otis AFB. Tick Mix.Rat.(q/kq) Cr=l (q/kq) marks shown on trajectories give positions at 1-h MidTrop 0.97 0.80 -0.13 63.4 intervals, or until the parcels exit the domain.

PBL 1.38 1.16 -0.25 55.2 SfcLayer 2.46 2.46 +0.25 33.3 SLvlPrs (mb) Cr=2.5 mb 0.69 0.62 +0.39 100.0