A new set of the Quarter Degree Grid Cell shapefiles has been generated. This time the coverage is global and the publication is for individual countries.
The QDGC shapefiles contain center lon/lat coordinates and the QDGC string for the different squares. The files are offered down to level four. For a country around the equator level four covers around 45 square kilometers with length and height a little under seven kilometres.
Read more about the use of QDGC on this page:
The calculations/export this time took around 60 hours computer pricessing time including generation of world fishnet with the different sizes, square area calculations, assigning QDGC strings, compression and more.
The below images shows how quarter degree grid cells covers Uganda.
Since last time I have moved the files to my own server. Figured out I wanted to have statistics for the files. The naming convention in the below list is based on the ISO 3166-1 alpha-3 standard. This means that the first three letters in the files below indicate which country the file is for. UGA is for example for Uganda.
Here is a list of country level files:
[wpfilebase tag=list id=10 tpl=table pagenav=1 /]
This i s a list of the continents files:
[wpfilebase tag=list id=11 tpl=table pagenav=1 /]
The associated code for generating the QDGC is kept in the following project on github:
I am so delighted to have found the resources you’re offering! I run an Africa wide mammal conservation project and am doing a lot of analyses of the spatial data. All the data I have are at GPS level and (for multiple reasons) I would like to scale these up to QDGC level. I see from comments on your website that you may have an Africa wide QDGC GIS layer, but I’m struggling to find this. Can you please point me in the right direction?
Also, please let me know how best to credit you in the analyses I do.
Hello Tali – good to be of help 🙂 I will try to prepare a Pan-African QDGC-file by tomorrow. It will consist of QDGC levels 1-4. Level 2 only is available for download here:
For credits just use the article we wrote some years back as a reference in papers or similar:
Thank you so, so much! Level 2 is actually the one I need for now, but I’d be happy to see what the other 3 levels look like when you get a chance to prepare them. Please dont rush on my account!!
Thanks so much,
Hello again Tali – QDGC 1-4 available for download. An update on the per country files are on their way 🙂
Continents and per country files of QDGC levels 1-4 are now available for download 🙂
For the country Tunisia, level 3 doesn’t work.
Thank you for your feedback. I will look into it, but can not promise any updates shortly. Try out the regional data sets (africa) in between, you might be able to find working files there.
Thanks. But there is no level 3 for Africa.