A global webservice to generate SWAT+ hourly and daily input climate files from ERA5 reanalysis data

TY - ABST

T1 - A global webservice to generate SWAT+ hourly and daily input climate files from ERA5 reanalysis data

AU - Lehmann, Anders

AU - Trolle, Dennis

AU - Nielsen, Anders

PY - 2023/6/28

Y1 - 2023/6/28

N2 - The ERA5 reanalysis dataset by the European Centre for Medium-Range Weather Forecasts (ECMWF) represents one of the latest and most accurate, consistent and globally available weather datasets. The raw data comes in hourly resolution, for the period 1950s to present, on a global grid of approx. 30km resolution. While accessing the data from the Climate Data Store by Copernicus is possible from a simple webpage or from scripts, this is a cumbersome process, and significant effort and multiple downloads are required when requesting long time series for multiple climate variables, which is often required when applying a hydrological model such as SWAT+. We developed a new Webservice that now provide an easy way to download and generate input climate files formatted directly for SWAT+ and a lake and reservoir model called GOTM-WET. The service provides a graphical user interface, which makes it easy to select the area and time period of interest.The motivation for creating the service was that the interface provided by ECMWF was quite slow and unpredictable to use in 2019, when we started working on providing SWAT+ modelling globally. We also found that converting units from ECMWF raw data to SWAT+, while not a hard problem, must be done correctly, and the service we developed ensures this. The service has two operating modes, depending on the way data is stored. The first mode accesses the ERA5 data sorted by time. In this mode it is simple to check the available time period, but somewhat slow. The second mode access the ERA5 data stored by location. In this mode it is quite fast to retrieve the wanted data. The SWAT+ input files is retrieved by downloading a zip file from a link sent in a mail when the files are generated. The service provides data from 1958-2023, which is the full time span of the 5 Tb ERA5 dataset. We demonstrate the use of the free Webservice, and also give an example of how SWAT+ can perform when using ERA5 data.

AB - The ERA5 reanalysis dataset by the European Centre for Medium-Range Weather Forecasts (ECMWF) represents one of the latest and most accurate, consistent and globally available weather datasets. The raw data comes in hourly resolution, for the period 1950s to present, on a global grid of approx. 30km resolution. While accessing the data from the Climate Data Store by Copernicus is possible from a simple webpage or from scripts, this is a cumbersome process, and significant effort and multiple downloads are required when requesting long time series for multiple climate variables, which is often required when applying a hydrological model such as SWAT+. We developed a new Webservice that now provide an easy way to download and generate input climate files formatted directly for SWAT+ and a lake and reservoir model called GOTM-WET. The service provides a graphical user interface, which makes it easy to select the area and time period of interest.The motivation for creating the service was that the interface provided by ECMWF was quite slow and unpredictable to use in 2019, when we started working on providing SWAT+ modelling globally. We also found that converting units from ECMWF raw data to SWAT+, while not a hard problem, must be done correctly, and the service we developed ensures this. The service has two operating modes, depending on the way data is stored. The first mode accesses the ERA5 data sorted by time. In this mode it is simple to check the available time period, but somewhat slow. The second mode access the ERA5 data stored by location. In this mode it is quite fast to retrieve the wanted data. The SWAT+ input files is retrieved by downloading a zip file from a link sent in a mail when the files are generated. The service provides data from 1958-2023, which is the full time span of the 5 Tb ERA5 dataset. We demonstrate the use of the free Webservice, and also give an example of how SWAT+ can perform when using ERA5 data.

M3 - Conference abstract for conference

T2 - 2023 Denmark SWAT Conference

Y2 - 28 June 2023 through 30 June 2023

ER -