Source:  EPA, User’s Guide for the AERMOD Meteorological Preprocessor (AERMET), http://www.epa.gov/ttn/scram/metobsdata_procaccprogs.htm#aermet.  November 2004,  Table D-3. Bowen Ratio for Various Land Uses  APPENDIX D$_{ }$ Surface Type  Winter  Spring  Summer  Autumn  Coniferous Forest  0.3  0.3  0.2  0.3  Swamp  0.5  0.1  0.1  0.1  Cultivated Land  0.5  0.2  0.3  0.4  Grassland  0.5  0.3  0.4  0.5  Urban  0.5  0.5  1.0  1.0  Desert Scrubland  2.0  1.0  1.5  2.0  For dispersion modeling, EDMS/AEDT requires the capacity of runway use configurations as  inputs to the Delay and Sequence Module. Configurations represent specific wind flows, cloud  ceiling, and visibility conditions. For such configurations, the airfield capacity should established (i.e., the number of departures during which the hourly arrivals are at maximum and  the number of arrivals during which the hourly departures are at maximum). The Aviation System Performance Metrics (ASPM) database can be used to establish the hourly  capacity of an airport. 84  Other spatial allocation parameters included in an air dispersion modeling analysis include the  following:  EDMS/AEDT and AERMOD incorporates specific details on source location (i.e., airport layout  and roadway network) and activity variation to develop a spatial representation of each emission  source. The locations of emission sources and receptors should be represented in the Universal  Transverse Mercator (UTM) coordinate system and the analysis should be centered on the airport  reference point. 85  Emission source locations can be determined using airport layout plans, aerial  photographs, drawings, maps, available databases, and/or site visits. The location of endpoints can be obtained from AEDT or the FAA’s Airport Master Record. 86  The percent of time the various runways are used for departures/arrivals are developed distribute the aircraft operations to each runway endpoint. To accommodate EDMS /AEDT and  AERMOD, the runway utilization is developed by aircraft size (i.e., small, large and heavy) for  each airfield configuration.  • Runway utilization  • Taxipaths  • Apron/Gate Assignments  84  FAA,  Aviation System Performance Metrics ,  https://aspm.faa.gov/aspm/entryASPM.asp. 85  The airport reference point is a point of an airport located at the geometric center of all the usable runways. 86  Airport IQ 5010, Airport Master Records and Reports, http://www.gcr1.com/5010web/. 81$_{ }$ D.2.4  Airport Capacity and Configurations  D.2.5  Spatial Allocation 