'VHPdownload' downloads a series of AVHRR and VIIRS images in a specific date or a period of dates. The format of the files are downloaded as GeoTiff, and they can be optionally returned as a Raster Time Series Object.
VHPdownload(x,dates,rts,ncore,...)product name; it can be either of c('VHI','VCI','SMN','SMT','TCI')
a vector, character or Date, with one or two items, specifiying an individual date or a range of dates as the form of c(from, to)
logical; specifies whether the downloaded files should be returned as a Raster Time Series object
numeric; specifies the number of cores to use for parallel downloading of the files
additional arguments (Not implemented yet.)
Babak Naimi
This function assists to download Blended Vegetation Health Indices Product (blended VIIRS (2013-present) and AVHRR (1981-2012), below, referred as Blended-VHP or VHP). These images for are available with a weekly temporal resolution and a spatial resolution of 4 KM. Five products are available that are specified with the following abbreviations:
- 'SMT': Smoothed Brightness Temperature
- 'SMN': Smoothed NDVI
- 'TCI': Temperature Condition Index
- 'VHI': Vegetation Health Index
- 'VCI': Vegetation Condition Index
Data arrays are in geographic projection (grid with equal latitude and longitude interval).