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NARCCAP.elev.rda is an R image object (4800X3000 cells
about 10Mb size) based on the USGS GTOP30 world elevation data product.
Resolution is approx 3km at the equator and ocean
cells are coded as missing (NA) and elevation is in meters.
NARCCAP.elev.small.rda for a version at one quarter this
resolution (1200X750, ~14 km ) and
1280X1280 image of the elevations in png format.
Sample R code:
attach( "NARCCAP.elev.rda") image( NARCCAP.elev, col=topo.colors(256))See GTOPO30 Documentation for details of the raw data formats and metadata. Refer to R source codes used to read (get.GTOPO30.R) and combine (make.NARCCAPelev.R) the GTOPO30 data to verify how the object was created. The high resolution version posted here is obtained by averaging the raw elevations from 4 cells to one to decrease the object size and make it easier to manipulate in an R session. (Thus the raw elevations are at a resolution of ~ 1.5 km at the equator.) It is easy to modify the processing to create an R object with the full resolution (see the shrink argument in get.GTOPO30).
NARCCAP_NCEPmovie.mp4 is an mpeg4 animation of the global NCEP preciptation rates for January 1979, an enlarged version over the NARCCAP domain and finally one of the precipitation fields for one of the regional models (ECPC). THe NCEP precipitation data (product)file pr_wtr.eatm.1979.nc (29M) is in netcdf format. It waS originally obtained from the NOAA Climate Data Center web archives. Please refer to this site for metadata information and netcdf file header for details about these data.
Source to draw the frames
In UNIX create the directory to hold the frames: mkdir temp In R: source("animate2a.R") # this will set up the data sets source("animnate2b.R") # does the specifics of drawing the frames
On a mac using Quicktime Pro just open the first image in the temp directory as an image sequence . Use the export option to convert to mpeg format.
Both scripts are easy to modify to include more models, rescale or change the color scales. Note that you only need to create the temp directory and source animate2a.R once if you decide to modify the graphics in animate2b.R