CERRA sub-daily dataset - Total Precipitation

Martin_Kaschner
Mon, 15 Sep 2025 12:51:35 +0000
C3S - Datasets and Usage

We are trying to look at total precipitation data, and I have noticed something awkward. I’m not sure if I misunderstood the data structure or if it’s simply an uncertainty. The documentation is a bit unclear.

I have downloaded two versions of the dataset: one with 3-hour steps (00:00, 03:00, 06:00, 09:00, 12:00, 15:00, 18:00, 21:00) and one with 6-hour steps (00:00, 06:00, 12:00, 18:00), total precipitation only.

My goal is to obtain the total precipitation over selected time intervals and specified areas, and then compare it with some historical reports (which are hand-drawn maps). When I extract these values from both datasets, I get similar but not identical results.

My question is: should I expect the results to be the same and there is an error somewhere in my workflow, or is this discrepancy expected?

And one more question: if I understand correctly, does the timestamp at 03:00 represent precipitation from 00:00 to 03:00, or from 03:00 to 06:00?

Thank you for your time.

2 posts - 1 participant