Roger W. BrodeU.S. EPA/OAQPS/AQADAir Quality Modeling Group

AERMOD Update

EPA Region 10 and State MeetingSeattle, WashingtonOctober 22, 2007

Outline

AERMOD Modeling System Update AERSCREEN Update AERSURFACE Update Questions

AERMOD Modeling System Status

AERMOD promulgation as preferred model in full effect as of December 9, 2006 – end of 1-year grandfather period

Significant updates to all three components released January 2007 (dated 06341)

Limited update to AERMOD released January 26, 2007 (dated 07026)

AERMOD Model Changes:Recent Enhancements

Updated processing for PM-2.5 NAAQS and removal of “post-1997” processing for PM-10

Additional options to vary emissions by month, hour-of-day and day-of-week (MHRDOW, MHRDOW7)

Multiple urban areas in single model run User-specified default in-stack NO2/NOx ratio for

Plume Volume Molar Ratio Method (PVMRM)

AERMOD Model Changes: Recent Enhancements (cont.)

New “BETA” option added to CO MODELOPT card to identify and allow use of new features added to the model that are still in a draft BETA-test status

– Non-DFAULT option– Allows for more efficient evolution of code by reducing need for

maintaining multiple versions

“Beta” options for capped and horizontal releases– EPA Model Clearinghouse procedure not applicable for PRIME

downwash algorithm

AERMOD Model Changes:Recent Enhancements (cont.)

“Beta” option to account for NO2/NOx plume chemistry of combined plumes in the computation of PSD increment consumption with credits for PVMRM

Maximum number of vertices for AREAPOLY source allocated dynamically

More memory-efficient process for allocating array storage

AERMOD Model Changes:Recent Bug Fixes

Several minor fixes for PRIME (mostly undefined variables)

Correct variable type error for AREACIRC sources (minor impact), and correct potential error for all AREA source types (impacts may vary)

Correct error for PVMRM when multi-level on-site wind data are used

A few additional minor bugs

AERMOD Model Changes:Miscellaneous Items

Added range check on VPTGZI in AERMOD to avoid problems with data provided from sources other than AERMET (e.g. gridded met models)

Tightened range checks on optional urban roughness length on URBANOPT card– Default of 1m should be used in most cases; values

greater than 5.0m not allowed; warnings issued for values less than 0.8m or greater than 1.5m

– More details presented later Miscellaneous code clean-up items

AERMOD Model Changes:Urban Roughness Length Issue

CO URBANOPT card includes option for user-specified urban roughness length; default value of 1.0m used if not specified

Urban Z0 used to adjust rural u* based on pseudo-convective urban w* to “urbanize” sigma-z for surface sources

Adjustment based on matching convective sigma-w profile with mechanical sigma-w profile at height of 7*Z0-urban

AERMOD Model Changes:Urban Roughness Length Issue

Considered removing option based on concern that unrealistic values were being used, and possible misinterpretation of how value is used in model:

– It does not adjust for difference in roughness between met site and urban application site

Performed sensitivity analysis to determine potential impact of removing option

Results showed sensitivity limited to low-level sources, but greater sensitivity than hoped for

Issue is being addressed in revised AIG, and next AERMOD update will treat non-default values as non-DFAULT

AERMOD Model Changes:Capped/Horizontal Releases

Current Model Clearinghouse procedure not applicable to PRIME– Clearinghouse procedure sets Vs low (0.001m/s) and

adjusts Ds to maintain flow rate and buoyancy

– PRIME numerical plume rise uses input Ds to define radius of plume – use of effective radius may alter results in physically unrealistic ways

– AERMOD Implementation Guide suggests using Vs=0.001m/s with actual Ds as interim solution

AERMOD Model Changes:Capped/Horizontal Releases

Draft/BETA options have been implemented for capped & horizontal– User inputs actual stack Vs and Ds

– Source types POINTCAP & POINTHOR used to trigger BETA options

– Non-downwash sources use Clearinghouse procedure– PRIME sources adjust plume radius (currently 2X) to

account for initial spread from cap– Partition vertical and horizontal momentum

Plume Rise Comparisons - Light Wind/Neutral - Vs=5.0m/s

1

10

100

1000

0.01 0.1 1 10 100 1000 10000

Downwind Distance (m)

Plu

me

Hei

gh

t (m

)

Vertical

Cappped

Horiz

Vs=.001

EqDiam

*** THE SUMMARY OF HIGHEST 1-HR RESULTS ***

DATE

GROUP ID AVERAGE CONC (YYMMDDHH)

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

STACK1 HIGH 1ST HIGH VALUE IS 2.97269 ON 90010102

STACK1C HIGH 1ST HIGH VALUE IS 2.98035 ON 90010102

STACK1H HIGH 1ST HIGH VALUE IS 72.16824 ON 90010102

STACK1C0 HIGH 1ST HIGH VALUE IS 19767.68555 ON 90010102

STACK1CE HIGH 1ST HIGH VALUE IS 2.97411 ON 90010102

AERMOD Model Changes:Capped/Horizontal Releases

AERMOD Model Changes:PVMRM PSD Credit Option

Define:– A = increment-consuming sources– B = existing (non-retired) baseline sources– C = increment-expanding (retired baseline) sources

Increment consumption without credits = (A+B) – B PSD Credit = (B+C) – B CHITOTAL = [(A+B) – B] – [(B+C) – B] = (A+B) – (B+C)

AERMOD Model Changes:Unresolved Issues/Planned Updates

Updated AERMOD Modeling System package planned ASAP to address:– Issues with portability of code to Linux for all three

components– Additional improvements to AERMOD memory allocation– Problems with AERMAP for Alaska DEM data– Cross UTM zone and edge receptor bugs in AERMAP– Format problem with some ISHD data may cause

AERMET to crash FIXISHD utility program – interim fix released in April

AERMOD Model Changes:Unresolved Issues/Planned Updates

Inconsistencies between NWS surface data formats– TD-3280 sky cover codes– Abbreviated ISHD (TD-3505) sky cover

Allocatable arrays for AERMAP and modifications to support National Elevation Dataset (NED)

PRIME/BPIPPRM issues– Split building/elongated building issues– Discontinuity at GEP stack height– Upwind impact of building on plume– Possible bug for “out-side cavity” source

AERMOD Model Changes:Unresolved Issues/Planned Updates

Upgrade Fortran compiler– Compaq Visual Fortran no longer supported– Recent “quirk” with Compaq Visual Fortran– Using open-source G95 compiler to debug codes– Upgraded to Intel compiler for Windows; limited tests

show about 40% improvement in runtime– Use of compiler option for double precision– Distribute Windows and Linux executables?

Updating user’s guides – convert to MS Word and merge with Addenda

AERMOD Update Questions

AERSCREEN Finalization Workgroup

Jim Haywood, Chair, Michigan DEQ Karen Wesson, EPA Roger Brode, EPA (formerly with MACTEC) James Thurman, EPA Bob Paine, ENSR Lloyd Schulman, TRC Acknowledge Herman Wong, EPA Region

10

What is AERSCREEN?

AERSCREEN refers to applying the AERMOD model in a “screening mode”

– SCREEN option added to AERMOD in 1995 forces model to calculate centerline concentration for each source/receptor/meteorology combination

– SCREEN option limits output to 1-hour averages and selects NOCHKD option to eliminate date sequence checking

AERSCREEN interface developed by Jim Haywood– AERSCREEN program provides interface to run AERMOD in

SCREEN mode, incorporates MAKEMET, BPIPPRM and AERMAP

– MAKEMET program generates matrix of meteorological conditions based on user-specified surface characteristics, formatted for input to AERMOD (.sfc and .pfl files)

Description of AERSCREEN

MAKEMET includes loops through meteorological parameters:

– Wind speed (stable and convective)– Cloud cover (stable and convective– Max/min ambient temp (stable and convective)– Solar elevation angle (stable and convective)– Convective velocity scale (w*) (convective only)– Mechanical mixing heights (stable only)

Uses AERMET subroutines to calculate u* and L, also calculates convective mixing heights

Generates AERMOD-ready surface and profile files with site-specific screening meteorology

Description of AERSCREEN

AERSCREEN command-prompt program developed by Jim Haywood, Michigan DEQ

– Interactive data entry (command prompts/DOS Screen)– Single point, volume, area or flare source– Flat or complex terrain (user-specified list of 7.5-minute or 1-

degree DEM – hopefully also 15-minute files soon)– PRIME building downwash (specify stack location for single tier

or provide BPIPPRM input file)– MAKEMET meteorology with site-specific surface characteristics– Search routine to locate worst-case impact location– Re-Use of previous AERSCREEN run files– Includes factors for 3-hour, 8-hour, 24-hour and annual averages;

similar to SCREEN3 factors (not finalized yet)

AERSCREEN Status

Draft AERSCREEN package submitted to EPA regions on 4/25/06 for internal (alpha) review and testing

Comments received from several regions and states; many comments related to problems with AERMAP

Public release of draft AERSCREEN package as soon as possible

AERSCREEN Status

ASCREEN program updated to use new AERMAP and AERMOD executables; AREA, AREACIRC and flare source options added

AERMET NR_ANG bug fix incorporated Surface characteristic options being modified

to provide some linkage with AERSURFACE Previous testing to be updated with latest

version; additional testing of AERSCREEN vs. on-site met data also planned

Additional documentation, including draft user’s guide and test results, needed before public release

AERSCREEN Tests

Significant testing to date shows good results across wide range of applications

“Good” defined as reasonable conservatism compared to AERMOD refined estimates

Testing performed for rugged terrain applications with downwash – minor modifications to MAKEMET

Database Type No. of sources

Max. Ratio

Min. Ratio

Median

Ratio

Jim Haywood Miscellaneous 7 5.20 1.09 2.35

Karen Wesson Stack downwash 32 2.54 0.96 1.17

Karen Wesson Stack non-downwash 26 2.18 0.97 1.49

Roger Brode

Flat Terrain

Non-downwash

Rural & Urban

168 2.98 0.98 1.05

Roger Brode

Complex Terrain

Varying Source/

Terrain Distance

168 4.56 0.96 1.18

Bob Paine Complex Terrain 28 7.46 1.08 2.23

ISC-AERMOD View - Lakes Environmental Software D:\Projects\G_Projects\G168-BC\BCASCR50.isc

PROJECT TITLE:

British Columbia AERSCREEN TestsSource Group Locations

PROJECT NO.:

SCALE:

0 10 km

1:476,448

COMMENTS:

MODELER:

COMPANY NAME:SOURCES:

7

RECEPTORS:

0

metersTerrain Contours

0.0 5.0 10.0 20.0 50.0 100.0 200.0 300.0 500.0 800.0 1200.0 1800.0 2400.0

0

0

0

0

0

0

0

0

0

5

5

5

5

5

5

5

5

5

5

5

5

5

5

5

10

10

10 10

10

10

10

10

10

10

10

10 10

10

10

10

10

20

20

20

20

20

20

20

20

20

20

20

20

50

50

50

50

50

50

50

100

100

100

100

100 10

0

100

100

200

200

200

300

300

300

300

300

300

500

500

500

500

500

500

800

800

80080

0

800

800

800

800

1200

1200

1200

1200

S7

S6

S5

S4

S3

S2

S1

470000 480000 490000 500000 510000 520000 530000 540000

5440

000

5450

000

5460

000

5470

000

5480

000

5490

000

Table 5.2b: Highest 1-hour Screening vs. Refined Results for SeaTac Airport Surface Characteristics

Source Location Source ID

Screening Q

Screening Elevation (m MSL)

Screening Hill Height Scale

(m MSL) Refined

Q

Refined Elevation (m MSL)

Refined Hill Height Scale

(m MSL) Screening/

Refined Ratio

S1 S1_LG 1.809 172 343 1.215 172 343 1.490

S1 S1_MD 11.063 7 7 9.610 7 7 1.151

S1 S1_SM1 1039.690 8 8 982.543 7 7 1.058

S1 S1_S10 637.866 7 7 354.042 8 8 1.802

S1 S1_SM2 357.879 7 7 343.719 7 7 1.041

S1 S1_S08 157.525 7 7 153.008 7 7 1.030

S2 S2_LG 22.772 183 203 20.287 183 203 1.122

S2 S2_MD 307.198 77 1178 226.239 82 1178 1.358

S2 S2_SM1 906.567 31 1178 905.019 31 1178 1.002

S2 S2_S10 1162.820 34 1178 829.149 39 1178 1.402

S2 S2_SM2 420.120 30 1178 397.065 29 1178 1.058

S2 S2_S08 399.932 49 1178 329.575 52 1178 1.213

S3 S3_LG 38.410 187 1178 24.717 193 1499 1.554

S3 S3_MD 257.356 78 1178 163.786 85 1178 1.571

S3 S3_SM1 6047.862 37 1178 1768.820 40 1178 3.419

S3 S3_S10 6047.862 37 1178 4662.883 39 1178 1.297

S3 S3_SM2 847.681 44 1178 882.339 44 1178 0.961

S3 S3_S08 599.342 49 1178 506.168 49 1178 1.184

S4 S4_LG 16.585 363 1178 12.337 366 1009 1.344

S4 S4_MD 79.196 254 1009 55.373 260 1009 1.430

S4 S4_SM1 1069.212 204 1009 1010.431 204 1009 1.058

S4 S4_S10 775.393 210 1009 615.640 215 1009 1.259

S4 S4_SM2 360.180 202 1009 330.230 201 1009 1.091

S4 S4_S08 155.487 202 1009 150.366 202 1009 1.034

S5 S5_LG 1.104 164 343 0.712 173 1009 1.551

S5 S5_MD 11.093 4 4 9.556 1 1 1.161

S5 S5_SM1 1068.335 4 4 988.166 3 3 1.081

S5 S5_S10 636.110 2 6 341.107 4 4 1.865

S5 S5_SM2 359.929 2 2 328.516 1 1 1.096

S5 S5_S08 155.917 2 3 151.804 2 2 1.027

S6 S6_LG 14.187 213 343 8.273 213 343 1.715

S6 S6_MD 143.747 108 108 83.777 118 202 1.716

S6 S6_SM1 5843.050 66 1178 3262.436 69 1178 1.791

S6 S6_S10 5843.050 66 1178 4850.776 69 1178 1.205

S6 S6_SM2 1294.519 76 1178 1065.870 76 1178 1.215

S6 S6_S08 644.158 65 1178 605.457 65 1178 1.064

S7 S7_LG 38.269 257 417 25.531 262 309 1.499

S7 S7_MD 597.878 146 417 377.833 152 417 1.582

S7 S7_SM1 5843.050 103 417 1276.771 104 417 4.576

S7 S7_S10 5843.050 103 417 4891.969 106 417 1.194

S7 S7_SM2 2130.484 112 417 2019.556 113 417 1.055

S7 S7_S08 976.258 117 417 851.028 117 417 1.147

Averaging Time Factors (still under development)

3-hour: fixed ratio of 0.95 (SCREEN3 = 0.90 ± 0.10); 8-hour: fixed ratio of 0.70 (SCREEN3 = 0.70 ± 0.20); 24-hour : fixed ratio of 0.40 for plume heights up to

100m, then linearly interpolated to a ratio of 0.30 for plume heights above 200m (SCREEN3 = 0.40 ± 0.20)

Annual: fixed ratio of 0.10 for plume heights up to 100m, then linearly interpolated to a ratio of 0.04 for plume heights above 200m (SCREEN3 = 0.08 ± 0.02).

Figure 1: AERSCREEN Averaging Period Ratios vs. Plume Height(line shows 95th-percentile and error bars show 90th and 98th percentiles)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0 50 100 150 200

3-hr

8-hr

24-hr

Annual

SCREEN 3-hr

SCREEN 8-hr

SCREEN 24-hr

SCREEN Ann

AERSCREEN:Topics for Discussion

Results from testing Averaging factors: Results? Fixed vs varying? Multiple source screening? MAKEMET and “site-specific” minimum wind

speed and anemometer height? Defaults?

AERSCREEN Questions

What is AERSURFACE?

AERSURFACE is a tool that produces surface characteristics data (albedo, Bowen ratio & surface roughness) for use in AERMET and/or AERSCREEN

Original program developed by Chris Arrington (WV DEP) and Larry Simmons (Energy & Environmental Management, Inc.)

New version being developed by EPA with contractor support (MACTEC)

AERSURFACE Description

EPA AERSURFACE program currently uses USGS NLCD 92 data– 21-category land cover classification scheme– 30 m spatial resolution– Currently draft supports both State and “seamless”

files AERSURFACE includes updated tables of

seasonal variations for surface characteristics data by land cover category

NLCD Land Cover CategoriesTable 1: USGS NLCD 92 Land Use Categories Classification Class Land Use Category

Open Water Water Perennial Ice/Snow Low Intensity Residential High Intensity Residential

Developed

Commercial/Industrial/Transportation Bare Rock/Sand/Clay Quarries/Strip Mines/Gravel Pits

Barren

Transitional Deciduous Forest Evergreen Forest

Forested Upland

Mixed Forest Shrubland Shrubland Non-natural Woody Orchards/Vineyards/Other Herbaceous Upland Grasslands/Herbaceous

Pasture/Hay Row Crops Small Grains Fallow

Herbaceous Planted/Cultivated

Urban/Recreational Grasses Woody Wetlands Wetlands

Emergent Herbaceous Wetlands

AERSURFACE Surface CharacteristicsTable A-3. Seasonal Values of Surface Roughness for the NLCD 92 21-Land Use Classification System

Seasonal Surface Roughness1 (m) Class

Number Class Name

1 2 3 4 5 Reference

11 Open Water 0.001 0.001 0.001 0.001 0.001 Stull2

12 Perennial Ice/Snow 0.002 0.002 0.002 0.002 0.002 Stull2 21 Low Intensity Residential 0.77 0.77 0.65 0.63 0.72 (22+43+85)/33

22 High Intensity Residential 1 1 1 1 1 AERMET 4

Commercial/Industrial/Transp (Site at Airport) 0.1 0.1 0.1 0.1 0.1 5%: 22 & 95%: 315

23 Commercial/Industrial/Transp (Not at Airport) 0.8 0.8 0.8 0.8 0.8 80%: 22 & 20%: 315 Bare Rock/Sand/Clay (Arid Region) 0.05 0.05 0.05 NA 0.05 Slade6 31 Bare Rock/Sand/Clay (Non-arid Region) 0.05 0.05 0.05 0.05 0.05 Slade6

32 Quarries/Strip Mines/Gravel 0.3 0.3 0.3 0.3 0.3 Estimate7 33 Transitional 0.2 0.2 0.2 0.2 0.2 Estimate8 41 Deciduous Forest 1.3 1.3 0.6 0.5 1 AERMET 4 42 Evergreen Forest 1.3 1.3 1.3 1.3 1.3 AERMET 4 43 Mixed Forest 1.3 1.3 0.95 0.9 1.15 (41+42)/2 9

Shrubland (Arid Region) 0.15 0.15 0.15 NA 0.15 50% 51 (Non-Arid)10 51 Shrubland (Non-arid Region) 0.3 0.3 0.3 0.15 0.3 AERMET 4

61 Orchards/Vineyards/Other 0.3 0.3 0.1 0.05 0.2 Garratt11 71 Grasslands/Herbaceous 0.1 0.1 0.01 0.005 0.05 AERMET 4 81 Pasture/Hay 0.15 0.15 0.02 0.01 0.03 Garratt11 & Slade12 82 Row Crops 0.2 0.2 0.02 0.01 0.03 Garratt11 & Slade12 83 Small Grains 0.15 0.15 0.02 0.01 0.03 Garratt11 & Slade12 84 Fallow 0.05 0.05 0.02 0.01 0.02 31 & 81,82,8313 85 Urban/Recreational Grasses 0.02 0.015 0.01 0.005 0.015 Randerson14 91 Woody Wetlands 0.7 0.7 0.6 0.5 0.7 (43+92)/215 92 Emergent Herbaceous Wetlands 0.2 0.2 0.2 0.1 0.2 AERMET 4

AERSURFACE Status

Draft AERSURFACE design document submitted to RO’s for review July 2006

Comments received from Regions and States, especially regarding draft look-up tables

Draft version of AERSURFACE being reviewed by AIWG

Recent changes to method for estimating surface characteristics from land cover data

AERSURFACE Design

Revisions to calculating area-weighted averages for surface characteristics:– Inverse-distance weighting to account for increased

width/area of sector with distance Revisions to calculation methods:

– Averaging ln(zo) for surface roughness– Geometric mean for Bowen ratio

Revisions to default domain/fetch distances:– 1km fetch for roughness– 10x10km domain for Bowen ratio and albedo – no

sector dependency

AERSURFACE Design

Default values/functions with several user choices:– Number of sectors (up to 12)– Output monthly, seasonal, or annual data– Wet/dry/normal conditions for Bowen ratio– Snow vs. no snow cover– Arid vs. Non-arid– Airport vs. Non-airport location

USGS NLCD 92: Example data

USGS NLCD 92: Example data

AERMET Stage 3 Formatted Datafrom AERSURFACE

** Generated by Internal Draft version of AERSURFACE, dated 07184

** Center Latitude (decimal degrees): 35.891940** Center Longitude (decimal degrees): -78.781940** Study radius (km) for surface roughness: 1.0 FREQ_SECT SEASONAL 12 SECTOR 1 0 30 SECTOR 2 30 60 SECTOR 3 60 90..

** Season Sect Alb Bo Zo SITE_CHAR 1 1 0.15 0.37 0.089 SITE_CHAR 2 1 0.14 0.30 0.118 SITE_CHAR 3 1 0.15 0.24 0.143 SITE_CHAR 4 1 0.15 0.37 0.123 SITE_CHAR 1 2 0.15 0.37 0.011 SITE_CHAR 2 2 0.14 0.30 0.016 SITE_CHAR 3 2 0.15 0.24 0.022 SITE_CHAR 4 2 0.15 0.37 0.016 SITE_CHAR 1 3 0.15 0.37 0.025 SITE_CHAR 2 3 0.14 0.30 0.032 SITE_CHAR 3 3 0.15 0.24 0.038 SITE_CHAR 4 3 0.15 0.37 0.032

Potential AERSURFACE Issue

ASOS station location uncertainties– Excel file with ASOS station locations available on NCDC

website is unreliable for location information– Additional data available for about 200 ASOS stations as part

of tropical cyclone wind study appears to be (generally) reliable

– Many station locations appear to be off by several hundred meters (median value of about 500m)

– Use of erroneous station locations in AERSURFACE could invalidate results

ASOS Met Station Locations – Cyclone Wind Study

ASOS Met Station Locations

Call WBAN Lat-ASOS Lon-ASOS Lat-PHOTO Lon-PHOTO Delta-Lat Delta-Lon Dist (km) ST Station NameKIJD 54767 41.7419 72.1836 41.7420 72.1830 0.000 0.001 0.061 CT Willimantic Windham Airport

KAQW 54768 42.6958 73.1708 42.6970 73.1700 -0.001 0.001 0.143 MA North Adams HarrimanKBED 14702 42.4700 71.2894 42.4680 71.2940 0.002 -0.005 0.498 MA Bedford Hanscom FieldKBOS 14739 42.3606 71.0106 42.3590 71.0200 0.002 -0.009 0.956 MA Boston Logan Intl AirportKBVY 54733 42.5842 70.9175 42.5840 70.9160 0.000 0.002 0.151 MA Beverly Municipal AirportKCQX 94624 41.6875 69.9933 41.6880 69.9930 -0.001 0.000 0.060 MA Chatham Municipal AirportKEWB 94726 41.6764 70.9583 41.6750 70.9570 0.001 0.001 0.193 MA New Bedford Municipal Airport

KFIT 4780 42.5519 71.7558 42.5520 71.7560 0.000 0.000 0.017 MA Fitchburg Municipal AirportKHYA 94720 41.6686 70.2800 41.6690 70.2710 0.000 0.009 0.900 MA Hyannis Barnstable Municipal AirportKMVY 94724 41.3931 70.6150 41.3920 70.6170 0.001 -0.002 0.226 MA Martha's Vineyard AirportKORE 54756 42.5700 72.2911 42.5720 72.2780 -0.002 0.013 1.327 MA Orange Municipal Airport

KOWD 54704 42.1908 71.1736 42.1910 71.1740 0.000 0.000 0.042 MA Norwood Memorial AirportKPYM 54769 41.9097 70.7294 41.9070 70.7280 0.003 0.001 0.308 MA Plymouth Municipal AirportKTAN 54777 41.8756 71.0211 41.8760 71.0210 0.000 0.000 0.046 MA Taunton Municipal Airport

KFWN 54793 41.2003 74.6231 41.2000 74.6170 0.000 0.006 0.606 NJ Sussex AirportKSMQ 54785 40.6239 74.6694 40.6170 74.6670 0.007 0.002 0.731 NJ Somerville Somerset AirportKVAY 93780 39.9406 74.8411 39.9500 74.8500 -0.009 -0.009 1.297 NJ Mount Holly South Jersey RegionalKALB 14735 42.7481 73.8033 42.7470 73.7990 0.001 0.004 0.446 NY Albany County Airport

KBGM 4725 42.2078 75.9814 42.2070 75.9800 0.001 0.001 0.159 NY Binghamton Regional AirportKELM 14748 42.1594 76.8919 42.1570 76.9030 0.002 -0.011 1.132 NY Elmira Corning Regional AirportKGFL 14750 43.3411 73.6103 43.3380 73.6100 0.003 0.000 0.312 NY Glens Falls AirportKISP 4781 40.7939 73.1017 40.8000 73.1000 -0.006 0.002 0.634 NY Islip Long Island Macarthur AirportKJFK 94789 40.6553 73.7956 40.6330 73.7670 0.022 0.029 3.622 NY New York J F Kennedy Intl Airport

KPEO 54778 42.6425 77.0564 42.6440 77.0530 -0.002 0.003 0.370 NY Penn Yan AirportKPOU 14757 41.6267 73.8842 41.6260 73.8820 0.001 0.002 0.226 NY Poughkeepsie Dutchess Co AirportKPSF 14763 42.4272 73.2892 42.4170 73.2890 0.010 0.000 1.022 NY Pittsfield Municipal AirportKSYR 14771 43.1092 76.1033 43.1110 76.1040 -0.002 -0.001 0.195 NY Syracuse Hancock Intl AirportKUCA 94794 43.1450 72.3839 43.1440 75.3840 0.001 -3.000 300.011 NY Utica Oneida County AirportKPVD 14765 41.7219 71.4325 41.7230 71.4330 -0.001 -0.001 0.117 RI Providence Green State AirportKUUU 14787 41.5300 71.2836 41.5300 71.2840 0.000 0.000 0.039 RI Newport State AirportKWST 14794 41.3497 71.7989 41.3500 71.7990 0.000 0.000 0.030 RI Westerly State AirportKDDH 54781 42.8914 73.2469 42.8940 73.2490 -0.003 -0.002 0.332 VT Bennington Morse State Airport

Comparison of ASOS Station Locations from Two References

NCDC ASOS List ASOS Cyclone Wind Study

AERSURFACE Questions