Abstract
The mean climatological distribution of convective environmental parameters from the ERA5 reanalysis and WRF regional climate simulations is evaluated using radiosonde observations. The investigation area covers parts of Central and Eastern Europe. Severe weather proxies are calculated from daily 1200 UTC sounding measurements and collocated ERA5 and WRF pseudo-profiles in the 1985–2010 period. The pressure level and the native ERA5 reanalysis, and two WRF runs with grid spacings of 50 and 10 km are verified. ERA5 represents convective parameters remarkably well with correlation coefficients higher than 0.9 for multiple variables and mean errors close to zero for precipitable water and mid-tropospheric lapse rate. Monthly mean mixed-layer CAPE biases are reduced in the full hybrid-sigma ERA5 dataset by 20–30 J/kg compared to its pressure level version. The WRF model can reproduce the annual cycle of thunderstorm predictors but with considerably lower correlations and higher errors than ERA5. Surface elevation differences between the stations and the corresponding grid points in the 50-km WRF run lead to biases and false error compensations in the convective indices. The 10-km grid spacing is sufficient to avoid such discrepancies. The evaluation of convection-related parameters contributes to a better understanding of regional climate model behavior. For example, a strong suppression of convective activity might explain precipitation underestimation in summer. A decreasing correlation of WRF-derived wind shear away from the western domain boundaries indicates a deterioration of the large-scale circulation as the constraining effect of the driving reanalysis weakens.
Highlights
Deep moist convection is frequent during spring and summer over the Pannonian Basin region, located within Central and Eastern Europe (Taszarek et al 2019; Seres and Horváth 2015)
We utilized 1200 UTC radiosonde observations to evaluate the mean climatological distribution of convective environmental parameters derived from the ERA5 reanalysis and WRF regional climate simulations
Collocated model profiles were inferred from both the pressure level and the native ERA5 dataset as well as two WRF runs with different grid spacings of 50 and 10 km
Summary
Deep moist convection is frequent during spring and summer over the Pannonian Basin region, located within Central and Eastern Europe (Taszarek et al 2019; Seres and Horváth 2015). Taszarek et al (2020c) (hereafter TA20) extended their work to the new generation ERA5 model level dataset. These studies compared several thermodynamic parcel parameters, moisture, temperature, and wind variables, along with composite indices derived from collocated observed and reanalysis profiles. TA20 suggested that a high vertical resolution in the boundary layer is beneficial for the accurate computation of buoyancy parameters. They did not present a direct comparison of results obtained from the pressure level and native ERA5 data
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
