What is the difference between NEMS, NEMS30, and ERA5T in history+, and which one should I use?
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For more precise evaluations, you can, for most locations, choose between high-resolution NEMS (4 -10 km resolution) and the low-resolution model (NEMS30). The availability of high-resolution NEMS data depends on the location and starts in 2008. The low-resolution NEMS with a spatial resolution of 30 km resolution is available as of 1984 which are all updated daily until the present.
ERA5T provides data since 1940, which are continuously updated but with a delay of 8 days. This is a re-analysis dataset that uses satellite data for post-processing. The dataset between 1940 and 1980 therefore might be of lower accuracy than the data from 1980 onwards due to the absence of satellite data. The ERA5 model is a legacy version of the ERA5T model and will be removed in the near future. Data are available between 1979 and March 2022, but this dataset will not be further updated. We, therefore, recommend using the ERA5T re-analysis model.
The weather data is always calculated for the grid cell centre and the average altitude of the grid cell. Temperature (and temperature-related) data are additionally downscaled to the respective altitude of the location. The location's altitude is defined using a high-resolution (80 meters) topography model.