Abstracted/indexed

Reanalyses are long-term meteorological datasets that are based on numerical weather prediction models and the assimilation of historic observations. The regional model COSMO of Germany’s national meteorological service (Deutscher Wetterdienst) has been used to develop regional reanalyses with spatial resolution of up to 2 km. In this paper, we provide an overview of evaluation results and application examples at the European and national German level with a focus on renewable energy.

This article describes the high-resolution Ensemble Prediction System (EPS) AEMET-γSREPS. This is the first convection-permitting EPS that operationally provide forecasts for a region of Antarctica. Kilometric-resolution EPSs, such γSREPS, will improve the short-range prediction in Antarctica in the following years. This will have a positive impact on safety and logistic activities at Antarctic research stations.

Access to high quality weather and climate data is crucial for a wide range of societal and economic issues. It allows optimising industrial processes with respect to efficiency. The goal of the research project FAIR is to simplify the information exchange between the DWD and economical players. This paper summarizes the results of the requirement analysis of three use cases and presents the deduced technical architecture and FAIR services aiming at a user-friendly exchange of weather data.

Wind speeds at turbine hub heights are scarcely measured and often replaced by numerical datasets when simulating wind power time series for various impact studies. Can we trust these modelled wind speeds? This work investigates five wind-speed datasets, comparing them to actual wind-speed and wind-power observations in France. They show various skills in terms of bias and hourly variability, leading to more or less realistic wind-power simulations at the local scale.

High-resolution precipitation observation based on signal attenuation in a Commercial Microwave Link (CML) network is an emerging technique that is becoming more and more used. Here a pragmatic method for estimating the optimal resolution is presented. The method is demonstrated using a CML network and a representative precpitation pattern in Stockholm, Sweden. One application would be feasibility investigations in cities considering starting CML-based precipitation observations.

A common framework for early action to cope with complex disasters can make it easier for authorities and populations at risk, to understand the full spectrum of impacts and thus where to focus preparedness efforts, and how best to provide more targeted warnings and early actions. There are useful lessons from Multi-Hazard Impact-based Early Warning Systems for the COVID-19 pandemic, and some valuable insight to be gained in risk communication, analysis and monitoring methodologies.

This article has been possible because of the cooperation between Television of Catalonia and the Applied Physics Department of the University of Barcelona, via the work of an intern student who was working from home because of the lockdown during the COVID19 pandemic. The mood of people we have studied in this article was similar to the one experimented by researchers. Weeks and months at home, with the only outside contact through the window, and social media.

In this study we look for a new knowledge of the costal boundary layer processes through analysis of extreme phenomena which include the verification of numerical modeling data outputs from the WRF mesometological model for selected period with high availability of extreme wind profiles by acoustic sounding of the atmosphere. The work is within the frame of research projects REPLICA (extReme Events and wind ProfiLe In a Coastal Area) – DM 14/1 26 May 2020.

We present the open source project Titan for automatic quality control of meteorological in-situ observations. The quality control strategy adopted is a sequence of tests, where several of them utilize the expected spatial consistency between nearby observations. Titan serves real-time operational applications that process massive amounts of observations measured by networks of automatic weather stations. Further developments include transforming Titan into a more flexible library of functions.

The present work deals with the spatial consistency of two well-known databases of solar radiation received at ground level: the CAMS Radiation Service database version 3.2, abbreviated as CAMS-Rad and the HelioClim-3 database version 5, abbreviated as HC3v5. Both databases are derived from satellite images. For both databases, there is no noticeable spatial trend in the standard deviation.

The power output of solar photovoltaic (PV) modules depends largely upon incident solar radiation as well as PV module temperature. Although irradiance can fluctuate rapidly under broken cloud conditions, module temperature is subject to latency due to the solar panel's heat capacity. In order to reconcile this difference a simple four-parameter model is successfully employed to describe the dynamics of PV module temperature as a function of atmospheric conditions.

This paper proposes new relationships for momentum exchange through the air–water interface for medium size lakes. High-resolution wind and wave measurements were performed simultaneously in onshore and offshore stations in Lake Balaton. Our results show that the surface drag is remarkably higher compared to open ocean conditions due to the very young wave state which is a typical feature of midsize freshwater lakes.

Statistics of the frequency and intensity of snow bands affecting the Finnish coast during years 2000–2010 was conducted. A set of criteria for meteorological variables favoring the formation of the snow bands were applied to regional climate model (RCA4) data. We found on average three days per year with favorable conditions for coastal sea-effect snowfall. The heaviest convective snowfall events were detected most frequently over the southern coastline.

Climate change projections for precipitation and temperature are a crucial element for stakeholders to make well-informed decisions on adaptation to new climate conditions. In this frame, the Pyrenees constitute a paradigmatic example of mountains undergoing rapid changes in environmental conditions. The impact of the scenarios becomes significant for the second half of the 21st century.

In this modelling study, we conclude that groundwater is used unsustainably for irrigation in several areas of the Euro-Mediterranean region. In the southern Iberian Peninsula, we estimate the potential effects of reducing irrigation groundwater abstractions to sustainable amounts to prevent long-term decline of groundwater storage. These restrictions may cause crop production losses but halt groundwater depletion and increase river flow during dry periods which is beneficial for ecosystems.

In the case of coastal wind farms, the wind that produces power simultaneously contributes to the cooling of high-voltage overhead conductors. Ideally this would allow for increased power transmission or decreased dimensions and cost of the conductor wires. In this study we investigate how well the wind speed in coastal wind farms is correlated with wind along a 75 km long 330 kW power line towards inland.

The single-column version of the shared ALADIN-HIRLAM numerical weather prediction system, called MUSC, was developed by Météo-France in the 2000s and has a growing user-base. Tools to derive the required input, to run experiments and to handle outputs have been developed within the HARMONIE-AROME configuration of the ALADIN-HIRLAM system. We also illustrate the usefulness of MUSC for testing and developing physical parametrizations related to cloud microphysics and radiative transfer.

The satellite-based fractional cloud cover and cloud top height from CLARA-A2 data record has been used to analyse trends in the Baltic Sea region, 1982–2015. Cloud observations from the Tartu-Tõravere meteorological station were used as reference data for the same period. A downward trend in fractional cloud cover in March over the 1982–2015 period was found. For cloud top heights summer and spring regional averages showed opposite signs of the trend: for June positive and for March negative.

We studied the applicability of seasonal forecast outputs in agriculture in Finland. The quality of seasonal forecasts output was assessed, and six tailored seasonal forecast indices were co-designed, developed in close collaboration with the Central Union of Agricultural Producers and Forest Owners and piloted with over 200 farmers. Although the tested seasonal forecast indices had a limited skill and need further improvements, the farmers found the climate outlooks useful.

Recently an objective method was suggested to translate realistic vegetation characteristics into spatially varying values of effective roughness. This parameter allows prediction of wind flow over vegetation using models, without incorporating local drag forces in each grid volume of a three-dimensional model domain. Results of the flow simulations over different forested sites show that an approach based on a roughness representation of forest is appropriate only for the flat terrain.

European NMHSs are progressing towards impact-oriented and impact-based warnings. This publication gives an overview of warning implementation as surveyed at 32 of the 37 NMHSs participating in the EUMETNET Meteoalarm project. Topics adressed include warning format, legislation and production process of warnings, dissemination and verification of warnings, impact databases, warning strategy and cooperation and cross-border collaboration. Obstacles are identified and trends are discussed.

This paper describes the approach and the process used for the development of TOPaCS, a contribution of RTC Italy to the WMO Global Campus initiative for ongoing continuous professional development in Meteorological and Climate Services. TOPaCS is open access and created under a Creative Commons licence, facilitating knowledge sharing and dissemination. TOPaCS is now available to the community of Climate Services through the platform www.climateservices.it.

To obtain reliable snowfall estimates in high mountain remains a challenge. This study uses daily snow water equivalent (SWE) estimates by a cosmic ray sensor on two Swiss glaciers to assess three readily-available high-quality precipitation products. We find a large bias between in situ SWE and snowfall, which differs among the precipitation products, the two sites, the winter seasons and in situ meteorological conditions. All products have great potential for various applications in the Alps.

Ensemble forecasting has gained popularity as a means of handling the limitations inherent to predicting the behavior of high dimensional systems with strong sensitivity to initial conditions. Initial conditions are sampled and propagated through the model equations, leading to a set of predictions. So far, this set has been interpreted in a probabilistic way. Here, we question this choice and show that possibility theory may be a sounder approach, especially in the case of extreme events.

Agricultural production is largely determined by weather conditions during the crop growing season. Weather events such as frosts, droughts or heat stress during crop growth and development helps explain yield variability of common arable crops. We developed a methodology and visualisation tool for risk assessment, and tested the workflow for drought and frost risk. The methodology can be extended to other extreme weather events and their impacts on crop growth in different regions of the world.

The Norwegian Meteorological Institute initiated the project TV meteorologists as climate communicators in 2019. Our goal was to make it easier for people to understand climate change and how it relates to local weather. The TV meteorologists have received extended training in climate issues, and in the last two years they have had 40 TV-appearances focusing on different local climate issues on the NRK Evening news. The majority of the stories have also been shared through social media.

Fall velocities of rain drops are reported for 2–3 mm drop diameters for several different turbulent intensities. The fall velocities are measured by 2D video disdrometers and the turbulence intensities by 100 Hz sonic anemometer. The findings are, (i) the mean fall speed decreases with increasing turbulent intensity, and (ii) the standard deviation increases with increase in the rms of the air velocity fluctuations.