Ten fold speed up using PostGIS2.1.SVN

One of the tasks that is commonly used in most spatial analysis at some point involves obtaining zonal statistics from a vector on raster overlay. This has always been rather inelegant using GRASS or Arc as it involves several steps. A PostGIS raster query simplifies the work flow. However in some cases my queries were…

Building more informative climate layers for species distribution modelling

The Worldclim data set is a fantastic resource for species distribution modelling. Not only does it include quality controlled monthly temperatures (minimum and maximum) and precipitation data but it also provides 16 derived bioclimatic layers that are designed to be universally applicable and interpretable. These layers are quite simple functions of the original data and…

Importing Modis fire pixels into PostGIS

Modis data are “big data” in every respect. Both the temporal and spatial extent of the information obtained from Modis makes data processing rather challenging. A quick overview of the Modis QuickFire data can be obtained by running the following code in R. A complete archive of all pixels recorded as having possible fire activity…