High-resolution (250x250m) gridded daily mean wind speed dataset for Austria spanning from 1961 to 2023

Overview:

Resolution: 250x250 mProjection: EPSG 31287, Austria LambertExtent: Austria Period : 1961-2023Format: NetCDF

Application:

High-resolution gridded climate data derived from in-situ observations play a crucial role in global and regional climatology. The data are a valuable input for further climate impact studies, particularly in ecological and energy modelling, and can be subsequently used for wind power potential analysis. Moreover, policymakers can make informed decisions based on accurate climate information derived from this dataset, enhancing the effectiveness of climate-related policies and interventions. Additionally, the data can be used for model evaluation and bias adjustment.

Methods:

1. Data homogenization

Breaks in the station data time series were detected and corrected using the Standard Normal Homogeneity Test (SNHT), which identifies where the mean changes the most. If this change exceeds a certain threshold, the time series is adjusted by aligning the statistical distribution of values before the change to those after the change, assuming the most recent time series is correct. This adjustment is achieved using the Quantile Mapping (QM) approach.

2. Spatial interpolation

All methods were tested in a nested 10-fold cross-validation (CV) scheme. This means that 10 % of the stations are left out (outer loop), and the other 90 % are used for training the model (inner loop). The outer loop is solely used for validating the model, whereas the inner loop serves for model optimization.

A two-stage approach was applied. Initially, a background field - the climatology for each month - was calculated using Random Forest Regression (RFR) with a defined set of predictors. Subsequently, model residuals were spatially interpolated using the 3D Inverse Distance Weighting (3D IDW) method. Differences between daily values and corresponding monthly climatologies were also interpolated using 3D IDW. The final daily mean wind speed field is calculated by adding the monthly climatology fields to the interpolated daily residuals.