California drought assessment
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This data set was developed using satellite imagery, MODIS (land cover, NPP, GPP, and ET) and PRISM (precipitation and scPDSI) data sets, for the entire state of California from 2002 to 2013. Satellite imagery was re-sampled to match the resolution of the scPDSI data set (4km) using bilinear methods of interpolation and re-projected to UTM WGS84 using the R library raster. To remove effects of possible changes in vegetation classes or errors in classification, cells that did not maintain the same ecosystem class over the study period were masked. Data sets were then stacked and converted to a data frame. This data set contains mean annual estimates for scPDSI, precipitation , leaf area index (LAI), gross primary productivity (GPP), net primary productivity (NPP), carbon update efficiency (CUE=GPP/LAI), and water use efficiency (WUE= NPP/ET).



