We examine the ability of an ensemble of 10 Regional Climate Models (RCMs), driven by ERA-Interim reanalysis, in skillfully reproducing key features of present-day precipitation and temperature (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008) over West Africa. We explore a wide range of time scales spanning seasonal climatologies, annual cycles and interannual variability, and a number of spatial scales covering the Sahel, the Gulf of Guinea and the entire West Africa. We find that the RCMs show acceptable performance in simulating the spatial distribution of the main precipitation and temperature features. The occurrence of the West African Monsoon jump, the intensification and northward shift of the Saharan Heat Low (SHL), during the course of the year, are shown to be realistic in most RCMs. They also capture the mean annual cycle of precipitation and temperature, including, single and double-peaked rainy seasons, in terms of timing and amplitude over the homogeneous sub-regions. However, we should emphasize that the RCMs exhibit some biases, which vary considerably in both magnitude and spatial extent from model to model. The interannual variability of seasonal anomalies is best reproduced in temperature rather than precipitation. The ensemble mean considerably improves the skill of most of the individual RCMs. This highlights the importance of performing multi-model assessment in properly estimating the response of the West African climate to global warming at seasonal, annual and interannual time scales.

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The relevance of carrying out marine warranty surveys (MWS) as mandatory insurable practice in mitigating associated operational risks within the offshore oil and gas industry, during the Covid-19 crises, was examined against the potential health risk and the various Covid-19 restrictions resulting from newly formed regulations. The health risk concerns to the surveyor and the impact of the Covid-19 policy restrictions for the surveyor’s business measured are against the risk of excluding MWS in assessing the suitability of procedures, analyses, and vessels involved in typical offshore marine operations. The purpose of any MWS undertakings ensures that all risks in operations, with potential to destroy property, life, and environment, are minimized—if not eliminated. A series of remote interviews across Africa and direct field observations were respectively conducted at the Takoradi port to develop an understanding of the MWS service product, to ascertain the conditions resulting from current challenges, and to determine contingencies and innovations to ensure full service. The study finds MWS service as paramount to the energy industry with its range of risk control checks for high-value assets and operations. Surveyors demonstrated high-levels of awareness for Covid-19 crises and regulatory policies while in adherence but noted challenges of high-cost and delays as by-products of the restrictions. Surveyors deemed site attendances as crucial in their practice at all time, though recognized the several social and technologically innovative approaches adopted industry-wide to facing the pandemic. The study highlights the need for ‘essential worker’ status and the introduction of innovative insurance packages. Supplementary Information The online version contains supplementary material available at 10.1007/s40152-021-00220-7.

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An evaluation of precipitation and evapotranspiration simulated by mesoscale models is carried out within the African Monsoon Multidisciplinary Analysis (AMMA) program. Six models performed simulations of a mesoscale convective system (MCS) observed to cross part of West Africa in August 2005.Initial and boundary conditions are found to significantly control the locations of rainfall at synoptic scales as simulated with either mesoscale or global models. When initialized and forced at their boundaries by the same analysis, all models forecast a westward-moving rainfall structure, as observed by satellite products. However, rainfall is also forecast at other locations where none was observed, and the nighttime northward propagation of rainfall is not well reproduced. There is a wide spread in the rainfall rates across simulations, but also among satellite products.The range of simulated meridional fluctuations of evapotranspiration (E) appears reasonable, but E displays an overly strong zonal symmetry. Offline land surface modeling and surface energy budget considerations show that errors in the simulated E are not simply related to errors in the surface evaporative fraction, and involve the significant impact of cloud cover on the incoming surface shortwave flux.The use of higher horizontal resolution (a few km) enhances the variability of precipitation, evapotranspiration, and precipitable water (PW) at the mesoscale. It also leads to a weakening of the daytime precipitation, less evapotranspiration, and smaller PW amounts. The simulated MCS propagates farther northward and somewhat faster within an overall drier atmosphere. These changes are associated with a strengthening of the links between PW and precipitation.