Precipitation–temperature relationships over Europe in CORDEX regional climate models

Abstract

We studied spatial and temporal patterns of precipitation-temperature (P-T) relationships through correlations between monthly standardized precipitation index (SPI) and monthly temperature anomalies in individual climatic seasons over Europe. In the observed data (represented by E-OBS), positive correlations (wet-warm/dry-cold relationships) prevail during winter over most of Europe, while negative values (dry-warm/wet-cold) are dominant in summer. In the next step, an ensemble of seven regional climate models (RCMs) from the CORDEX project driven by the ERA-Interim reanalysis were examined as to their reproduction of the regional patterns of the P-T correlations. In winter, the RCMs yielded overly strong positive P-T correlations over northern Europe, while the correlations were too weak in the south compared to observed data. During summer, the biases were generally larger; the RCMs were able to capture the overall negative P-T correlations but these tended to be too weak over northern Europe. This deficiency was found to be linked to simulated differences in shortwave radiation (a proxy for cloud cover) between dry and wet months. In western, central, and southeastern Europe, by contrast, most RCMs yielded too strong negative correlations in summer, and overly large decreases of relative humidity during dry months probably contributed to these errors. The results pointed up issues that should be addressed as the reported RCMs' deficiencies may lower credibility of projected compound dry-hot events in climate change scenarios.

Three-dimensional analysis reveals diverse heat wave types in Europe

“…It should be noted that precipitation observations are not assimilated into the ERA5 reanalysis but produced through large-scale cloud and precipitation schemes and parametrization of convection 19,42 . Therefore, uncertainties in the precipitation-temperature relationship 43 may affect the near-surface layers' temperature and heat wave 3D types, which will be addressed in further studies employing the E-OBS data set 44 for reference precipitation.…”

Prolongation of Compound Dry–Hot Seasons Over Europe Under Climate Change Scenarios

“…A number of methods for estimation of PET were introduced but none of them outperforms others globally, as their performance is often linked to certain climatic region (Valipour et al., 2017). Some studies have reported that more complex radiation‐based models perform better under climate change conditions (Sheffield et al., 2012) but they demand variables (e.g., relative humidity, solar radiation, and wind speed) often laden with errors in RCMs (Lhotka & Kyselý, 2022b; Vautard et al., 2021), thus increasing uncertainties originating from climate models' selection. In addition, the limited requirements for input data in the Oudin's method allow evaluating the climate models against the established gridded observation‐based products (such as the E‐OBS data set; Cornes et al., 2018).…”

“…These variations between the sub-ensembles are linked to future changes in temperature, precipitation, and the mutual relationships between these two. Lhotka and Kyselý (2022b) showed that CORDEX RCMs have difficulties in reproducing links between summertime precipitation and temperature on the monthly scale and that these biases are RCM-dependent. In addition, differences between sub-ensembles are probably also linked to simulations of future changes in atmospheric circulation patterns (Zappa & Shepherd, 2017).…”

Large-scale spatial variation and phenotypic integration in three Argynnini species inform about functions and evolutionary drivers of butterfly wings

“…In F. adippe and F. niobe, melanisation increased with precipitation. We propose that because precipitation is often negatively correlated with temperature in European summers (Lhotka and Kyselý, 2022), exhibiting darker wings might be beneficial in areas with high precipitation. Together, these results strengthen the conclusion that the thermal milieu is a crucial selective driver for the degree of melanism in insects, and ectotherms generally.…”