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ABSTRACT Recent special reports on climate extremes have shown evidences of changes in the patterns of climate extremes at global, regional and local scales. Understanding the characteristics of climate extremes at regional and local levels is critical not only for the development of preparedness and early warning systems, but is also fundamental in the development of any adaptation strategies. There is still very limited knowledge regarding the past, present and future patterns of climate extremes in the Greater Horn of Africa (GHA). This study, which was supported by the World Bank Global Facility for Disaster Reduction and Recovery (WB-GFDRR) and implemented by the World Meteorological Organization, was organized in terms of three workshops with three main objectives; (1) analysis of daily rainfall and temperature extremes for ten countries in the GHA region using observed in situ data running from 1971 to 2006, (2) assessing whether the United Kingdom Met-office and Hadley centre Providing REgional Climates for Impact Studies (UK-PRECIS) modelling system can provide realistic representation of the past and present climate extremes as observed by available in situ data, and (3) studying the future regional climate extremes under different scenarios to further assess the expected changes in climate extremes. This paper, therefore, uses the outputs of these workshops and also includes post-workshop analyses to assess the changes of climate extremes within the GHA. The results showed a significant decrease in total precipitation in wet days greater than 1 mm and increasing warm extremes, particularly at night, while cold extremes are decreasing. Considering a combination of geophysical models and satellite gravimetry observations from the Gravity Recovery and Climate Experiment (GRACE) mission in the frame of GRACE daily Kalman-smoothing models, for the years 2002 to 2010, we explored a decline in total water storage variations over the GHA. [ABSTRACT FROM AUTHOR]

The flora and vegetation of the archipelago of Cabo Verde is dominated by Macaronesian, Mediterranean, and particularly by African tropical elements, resulting from its southernmost location, when compared to the other islands of the Macaronesia (i.e., Azores, Madeira, Selvagens, and Canary Islands). Very likely, such a geographical position entailed higher susceptibility to extreme climatic fluctuations, namely those associated with the West African Monsoon oscillations. These fluctuations led to a continuous aridification, which is a clear trend shown by most recent studies based on continental shelf cores. Promoting important environmental shifts, such climatic fluctuations are accepted as determinant to explain the current spatial distribution patterns of taxa, as well as the composition of the plant communities. In this paper, we present a comprehensive characterization of the main plant communities in Cabo Verde, and we discuss the role of the climatic and topoclimatic diversity in shaping the vegetation composition and distribution of this archipelago. Our study reveals a strong variation in the diversity of plant communities across elevation gradients and distinct patterns of richness among plant communities. Moreover, we present an overview of the biogeographical relationships of the Cabo Verde flora and vegetation with the other Macaronesian Islands and northwestern Africa. We discuss how the distribution of plant communities and genetic patterns found among most of the endemic lineages can be related to Africa's ongoing aridification, exploring the impacts of a process that marks northern Africa from the Late Miocene until the present. [ABSTRACT FROM AUTHOR]

As a result of the world-wide attention that global climate change is receiving, laudable attempts are made to increase the share of renewable energies in electricity production around the globe. In addition to climate change issue, the need for bringing electricity to millions of people who live in the least-developed parts of the world act as a stimulus to the development of renewable energy share of electricity generation. Despite all efforts, a considerable number of people in rural and remote areas of Africa are still striving to gain access to energy. This issue has been partly addressed by the introduction and development of off-the-grids (stand-alone power systems) using renewable energy sources, including wind. The key aim of this research is to study wind power as a source of electrification in Africa. Renewable energy supply is very vulnerable to hydro-climatic variability and extreme hydro-meteorological events, and wind energy is no exception. In particular, low wind speeds throughout Africa pose a real challenge to electricity generation from wind. Using hourly estimates of wind speed provided by ERA5 (the latest climate reanalysis produced by ECMWF), this paper evaluates spatial and temporal variability in daily wind power production across Africa, for a 18-year period (from 2000 to 2017), in terms of the capacity factor of wind (the average wind power generated each day divided by the rated peak power), and the minimum required wind speed for power production (useable wind speed). Furthermore, by calculating the low percentile values of daily capacity factors, we gain understanding of the ability of wind turbines to achieve a given level of service quality, and put an economic perspective on wind power production. [ABSTRACT FROM AUTHOR]