Hi, I wanted to ask if there is a preferred or recommended approach for downloading bulk data. I’ve been tasked to download 46 years of hourly data for 10 variables from the global ERA5 single level 0.25° resolution dataset (“reanalysis-era5-single-levels”). These are going to be used to drive a se…

Just to follow up, this process was running as a 24hr job on our HPC queue. I’ve used the new ecmwf-datastores-client to automatically grab the updated set of completed requests (nice functionality by the way!) and get the data below. The actual request processing time is basically completely static…

For bulk downloads like this, it might be worth taking a look at ERA5 data mirrored at Google: https://console.cloud.google.com/storage/browser/gcp-public-data-arco-era5;tab=objects?prefix=&forceOnObjectsSortingFiltering=false

The ECMWF brand new ARCO data implementation was a huge help here: Analysis Ready Cloud Optimised (ARCO) Data - Copernicus Knowledge Base -... It didn’t have all the variables I am after - and for those variables this question still stands - but is much faster…

Yes, it’s fantastic to see ARCO data becoming available for ERA5. This is essentially how we’ve been processing & storing ERA5 / ERA5Land data for the past 5 years and it’s great to see agencies such as ECMWF adopt ARCO formats.

Really love to see ARCO versions of ERA5/ERA5-Land become available, and thank you to any and all that helped make it possible! Related to this question of bulk downloads, I wondered if there are any general guidelines regarding the quantity of data users should target for accessing/downloading thro…

Hi @Durban_Keeler , we have been intentionally vague on the rate-limits implemented as they are subject to change as we launch this new service. Our systems are quite robust and the rate limiting is implemented dynamically, so you should not need to modify scripts to be a good citizen. We cap your …

Recommended strategy for bulk downloads

Datasets and Usage C3S - Datasets and Usage

Edward_Comyn-Platt 1 July 2026 12:20 6

Hi Everyone,

Just to let you know that the ARCO ERA5 and ERA5-land data is now fully published and documented on the CDS dataset pages. Please see this announcement for more details: