Latest Contributions by DavidAskov1

Hi everyone, I have some WRF model output data in NetCDF format, and I would appreciate any guidance on projecting it from anyone with experience with data from this model. (WRF = Weather Research Forecasting) These WRF runs use a Lambert Conformal Conic projection with a center of -121, standard parallels of 30 & 60 degrees North, and a latitude of origin of 45 degrees North. I think I have that figured out, but my data will be off if I don't use the right sphere/spheroid. My understanding is that WRF uses a sphere of 6370 KM with no flattening. Does this look right?  PROJCS["WRF_LCC_PacificNW",     GEOGCS["WRF_Sphere_6370km",         DATUM["<custom>",             SPHEROID["<custom>",6370000.0,0.0]         ],         PRIMEM["Greenwich",0.0],         UNIT["Degree",0.0174532925199433]     ],     PROJECTION["Lambert_Conformal_Conic"],     PARAMETER["False_Easting",0.0],     PARAMETER["False_Northing",0.0],     PARAMETER["Central_Meridian",-121.0],     PARAMETER["Standard_Parallel_1",30.0],     PARAMETER["Standard_Parallel_2",60.0],     PARAMETER["Scale_Factor",1.0],     PARAMETER["Latitude_Of_Origin",45.0],     UNIT["Meter",1.0] ] ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍ If that is right (or if I need to adjust it), then I should be all set. I would appreciate any feedback I can get from anyone with experience in this. Based on slide 20 of this presentation, it looks right, but I'd appreciate as much help as I can get! That said, my process to bring these into ArcGIS is not for analysis is not straightforward at all, and I'd appreciate any suggestions to improve it. Here is how I do it:  Use Make NetCDF Raster Layer to import to an in-memory raster and save to a GeoTIF. The GeoTIF has headers for the coordinate system, but it comes in as pixel coordinate space with no registration. Unfortunately, the Esri Define Projection did not work on this. I saw several other people griping about this in this forum.  I use gdal_translate.exe -co PROFILE=BASELINE to strip out the file's coordinate system headers in the GeoTIF.  I pre-generate a TFW and copy it to <filename>.tfw in the folder where <filename>.tif lives. (I do this for each time slice in the NetCDF that I export.) The NetCDF gives me the lower left, and I need the upper left in the TFW, so some basic math is needed with the cell size and number of rows.  Use Define Projection to put it into the right coordinate system. It works now that there are no GeoTIF headers and a TFW file exists.  I'm doing this in Python and it's automated. It doesn't take long, but YUCK! It seems like a lot of steps to get the data into the right coordinate system, especially considering that it came from a file where the coordinate system is well-defined, albeit in a different format. After this, I do some resampling, averaging, and export to polygons, so I feel like TIFs are a good intermediate format, but there is clearly room for improvement... thanks! ... View more

Hi - I'm trying to produce contour polygons out of a Geostatistical Analyst layer. The contour polygons (GALayerToContour_ga tool) are super-generalized and look terrible. This screenshot shows is the resulting contour polygons in blue lines (transparent fill). The grid in the background was exported from the GA Layer (using the GALayerToGrid_ga tool), with the colors classified at the same cut-off elevations used to generate the contours: My question is: How do I generate contour lines that really follow the data much more closely? Is there some kind of scale or generalization setting in the environments that I'm missing? Here is what I am running: arcpy.GALayerToContour_ga(     in_geostat_layer="output_geo_lyr",     contour_type="FILLED_CONTOUR",     out_feature_class=output_path,     contour_quality="PRESENTATION",     classification_type="MANUAL",     classes_count="5",     classes_breaks="5;20;75;150;999999") Here is how I created the GA layer. It actually came from a raster-to-point export. For that reason, I set the min and max number of inputs to 1, to basically just make it a nearest neighbor interpolation: arcpy.IDW_ga(     in_features=in_features,     z_field="grid_code",     out_ga_layer="output_geo_lyr",     out_raster="",     cell_size="0.01",     power="2",     search_neighborhood="NBRTYPE=Standard S_MAJOR=1.1 S_MINOR=1.1 ANGLE=0 NBR_MAX=1 NBR_MIN=1 SECTOR_TYPE=ONE_SECTOR",     weight_field="") When I check the GA Layer with the GALayerToGrid_ga, it looks correct.That is the background in the screenshot above. If I run the Spatial Analyst Contour List tool, that creates something much more reasonable. Of course, these are just lines, so they don't meet my needs, since I'm trying to create polygons. Here is a view of those: Any ideas on how I can create polygons with boundaries that look like the lines in this screenshot? thanks! The Python script I'm using is attached. It runs and produces the grid background and polygon foreground in the first screenshot, above. I'm using ArcGIS Desktop 10.5 with its arcpy 2.7. ... View more