I have a spatio-temporal point data of species sighting with monthly observation for random locations within my study area. I wish to create a grid(fishnet) for each month for each year. Also, certain grids for a month and year has multiple points so need to derive mean.
Old [I have point data for an area over a period of years (2010-2014). I would like to create a grid of 0.25 X 0.25 decimal degrees for each month. Also to derive a mean where there are more than one point in a grid mesh for that particular month. Purpose of creating this grid is to extract the values from rasters based on the grid.]