Problems in making CLM files with DIVA-GIS

Question

I am fairly new to GIS softwares and this will be my first post here. I'm working with DIVA-GIS and was redirected here. I hope this is the correct place. I am doing a research which involves ecological niche modeling for present and future climate scenarios. However, i am having some urgent problems with creating the .clm files for the predicted future climate. I have downloaded the necessary data from WorldClim. I have followed the instructions from "Ramirez & Bueno, 2009, Working with climate data and niche modeling: Creation of bioclimatic variables", but DIVA GIS doesnt seem to want to create the files. Basically, i open up the "Make CLM files" window in DIVA GIS, and have all the necessary 36 .grd files + the alt.grd required for the operation. I have correctly inserted the prefixes and ticked their boxes. As soon as i press "OK", these boxes automatically uncheck, the 36 files are not split into the "selected files" spaces present in the window, and the program only creates the single climate.cli files. I have found this question being asked on the internet but with no answer. I have no idea how to solve the issue as everything seems to have been done correctly. Does anybody have an idea? Help would be greatly appreciated.

Thank you all.

Alessandro

Answer 1

I ran into the same problem… follow this guide from steps 5 and onwards if you have not already done so. http://www.ccafs-climate.org/downloads/docs/Ramirez_Bueno-Cabrera_2009_tutorial_bcvars_creation.pdf

The EXACT file naming is critical!!! In the upper file prefix window change the prefixes to “tmin_” for Tmin, “tmax_” for Tmax and “prec_” for Precipitation; Then rename each of the 36 files to match the prefix (ie. change tmin10_11.grd -> “tmin_10.grd"). So in the end you should have a folder with 36 grd and 36 gir files (tmin_1.grd, tmin_1.gri, tmin_2.grd, tmin_2.gri, ect. (NOT "tmin1_11.grd").

Another important consideration is file size and storage capacity. If you download and create monthly tmin values for each month at a 1km/1km resolution for the entire planet, Diva-GIS will just freeze out. I would suggest downloading and merging only the tiles you need… then follow steps to convert (BIL - > grd)

http://www.worldclim.org/formats

Good luck,

Matt