28. Appendix B Map Projections, Grids, and Polylines¶
28.1. Map Projections¶
The following map projections are currently supported in MET:
Lambert Conformal Projection
Polar Stereographic Projection (Northern)
Polar Stereographic Projection (Southern)
Mercator Projection
Lat/Lon Projection
Rotated Lat/Lon Projection
Gaussian Projection
28.2. Grids¶
All of NCEP’s pre-defined grids that reside on one of the projections listed above are implemented in MET. The user may specify one of these NCEP grids in the configuration files as “GNNN” where NNN is the 3-digit NCEP grid number. Defining a new masking grid in MET would involve modifying the vx_data_grids library and recompiling.
Please see NCEP’s website for a description and plot of these pre-defined grids:
28.3. Polylines for NCEP Regions¶
Many of NCEP’s pre-defined verification regions are implemented in MET as lat/lon polyline files. The user may specify one of these NCEP verification regions in the configuration files by pointing to the lat/lon polyline file in the installed share/met/poly directory. Users may also easily define their own lat/lon polyline files.
See NCEP’s website for a description and plot of these pre-defined verification regions: http://www.emc.ncep.noaa.gov/mmb/research/nearsfc/nearsfc.verf.html
The NCEP verification regions that are implemented in MET as lat/lon polylines are listed below:
APL.poly for the Appalachians
ATC.poly for the Arctic Region
CAM.poly for Central America
CAR.poly for the Caribbean Sea
ECA.poly for Eastern Canada
GLF.poly for the Gulf of Mexico
GMC.poly for the Gulf of Mexico Coast
GRB.poly for the Great Basin
HWI.poly for Hawaii
LMV.poly for the Lower Mississippi Valley
MDW.poly for the Midwest
MEX.poly for Mexico
NAK.poly for Northern Alaska
NAO.poly for Northern Atlantic Ocean
NEC.poly for the Northern East Coast
NMT.poly for the Northern Mountain Region
NPL.poly for the Northern Plains
NPO.poly for the Northern Pacific Ocean
NSA.poly for Northern South America
NWC.poly for Northern West Coast
PRI.poly for Puerto Rico and Islands
SAK.poly for Southern Alaska
SAO.poly for the Southern Atlantic Ocean
SEC.poly for the Southern East Coast
SMT.poly for the Southern Mountain Region
SPL.poly for the Southern Plains
SPO.poly for the Southern Pacific Ocean
SWC.poly for the Southern West Coast
SWD.poly for the Southwest Desert
WCA.poly for Western Canada
EAST.poly for the Eastern United States (consisting of APL, GMC, LMV, MDW, NEC, and SEC)
WEST.poly for the Western United States (consisting of GRB, NMT, NPL, NWC, SMT, SPL, SWC, and SWD)
CONUS.poly for the Continental United States (consisting of EAST and WEST)