Most downloaded  

Sensitivity analyses for wind direction effects upon an ENVI-met microclimate model were performed for a heterogeneous urban study area. Significant temperature differences were found when forcing the model with constant N/E/S/W wind direction data. Best model performance was observed using measured wind direction forcing data. The results demonstrate that cooling effects of park areas are largely directional which is important for urban planning and design of climate change adaptation measures.

Atmospheric boundary layers are inherently unsteady and exhibit processes on multiple scales. A stochastic one-dimensional turbulence model is applied here to periodically forced Ekman flows. These flows are hard to model due to competing laminar and turbulent response mechanisms. It is shown that the model is able to capture parametric dependencies of the near-surface turbulence. The results consolidate improvements seen in a subgrid-scale application of the model within large-eddy simulations.

The weather information value chain is a framework that describes how information is produced, communicated, and used in an end-to-end warning system for weather and hazard monitoring. A project under the WMO aims to explore value chain approaches to describe and evaluate high-impact weather events. The project developed a template for high-impact weather event case study collection, which allows scientists and practitioners to assess the effectiveness of warning value chains.

This method generates probabilistic solar power forecasts of up to 30 min using artificial intelligence and fish eye images of the sky. We investigated the impact of parameters describing the variability of the solar power on the forecast performance and divided the solar power to its direct and diffuse components. The method achieves overall good performance, while variability parameters and dividing the solar power don't show any performance gain. However, training time can be decreased.

The quality of the global reanalysis ERA5, the regional reanalysis COSMO-REA6 and a successor version (R6G2), the new Copernicus European Regional Re-Analysis (CERRA) and a regional downscaling simulation with COSMO-CLM (HoKliSim-De) is assessed for offshore wind farm planning in the German Exclusive Economic Zone (EEZ) of the North Sea. The quality is assessed using in-situ wind measurements at the research platform FINO1 and satellite-based data of the near-surface wind speed as reference.

We present a wind power forecasting procedure, that consists of a physics-based component generated at a central server, and a data-based component generated on-site the wind power plant (WPP). It provides blackout-robust data transmission to grid operators and high forecast reliability, especially in the very-short term horizon. This endeavor aims at employing WPPs for support in exceptional or critical grid situations, where short term decision making is most relevant.

In this work, we present the most recent updates in the E-OBS gridded data set for daily mean wind speed over Europe. The data set is provided as an ensemble of equally likely realisations. In addition, we make a preliminary study into possible causes of the observed terrestrial wind stilling effect, such as local changes in surface roughness length. As one of the results, we do observe a terrestrial wind stilling effect, however, the trend varies locally over Europe.

In 2021, several weather disasters occurred in which conditions surpassed recorded extremes. Comparative analysis of the warnings issued for these disasters shows that the conditions were generally forecast but that lack of preparedness and/or communication failures led to loss of life in particularly vulnerable groups.

The importance of the ABL studies is essential because we live and work in it. The presented study is based on long-term acoustic soundings data for the coastal atmosphere. Such data is of great importance for the study and the theoretical description of the atmospheric processes in similar complex terrain regions and can be used for validation of different NWP and prognostic air pollution models. Such data is critically needed for the development of improved ABL parametrization schemes.

We considered it important to complete the content knowledge of secondary school physics with those concerning atmospheric humidity, fog, and air pollution. For this aim, a three-hour teaching module was elaborated, which included the analysis of the air-polluting events together with the foggy weather. The experimental curriculum motivated the students to understand processes that take place in their environment regarding environmental protection.