Mamadou Simina Drame

Impacts of aerosols on available solar energy at Mbour, Senegal

This study aims to evaluate the available solar potential (direct normal on the overall horizontal plane) and to estimate the observed impact of aerosols on solar radiation at Mbour, Senegal (16.958 °W; 14. 394 °N) using observations from solar instruments and AERONET during 2006. The results show the presence of a good available solar potential. At intra-seasonal timescale, the total and direct normal energy are stronger in May with a mean value of 7 kWh/m2/day and February with an average value of 5.50 kWh/m2/day. The lower available total and direct normal solar energies are, respectively, found in August (5.31 kWh/m2/day) and July (2.90 kWh/m2/day). The observations of AERONET show that aerosol optical depth values are higher in June (0.7) and lower in February (0.16). These results are consistent with the observed trends of total and direct normal energy during those months. Case studies of the influence of aerosols on available solar energy show a mean decrease of 10% and 28%, respectively, for the ...

Linkages between observed, modeled Saharan dust loading and meningitis in Senegal during 2012 and 2013

The Sahara desert transports large quantities of dust over the Sahelian region during the Northern Hemisphere winter and spring seasons (December–April). In episodic events, high dust concentrations are found at the surface, negatively impacting respiratory health. Bacterial meningitis in particular is known to affect populations that live in the Sahelian zones, which is otherwise known as the meningitis belt. During the winter and spring of 2012, suspected meningitis cases (SMCs) were with three times higher than in 2013. We show higher surface particular matter concentrations at Dakar, Senegal and elevated atmospheric dust loading in Senegal for the period of 1 January–31 May during 2012 relative to 2013. We analyze simulated particulate matter over Senegal from the Weather Research and Forecasting (WRF) model during 2012 and 2013. The results show higher simulated dust concentrations during the winter season of 2012 for Senegal. The WRF model correctly captures the large dust events from 1 January–31 March but has shown less skill during April and May for simulated dust concentrations. The results also show that the boundary conditions are the key feature for correctly simulating large dust events and initial conditions are less important.

The use of ALADIN model and MERRA-2 reanalysis to represent dust seasonal dry deposition from 2006 to 2010 in Senegal, West Africa

The objective of this work is to study the seasonal distribution of dust dry deposition in West Africa particularly in Senegal. This initiative is part of the efforts to improve the performance of photovoltaic panels (PV) in dusty environments such as Sahel region. It will help to evaluate the impact of dust dry deposition on these PV. Two climate models including dust modules during 2006–2010, were used: MERRA-2 (Modern-Era Retrospective Analysis for Research and Applications, version 2) reanalysis and ALADIN (Aire Limitée Adaptation dynamique Développement InterNational) model. In Mbour (Senegal), the aerosol optical depth (AOD) from these two products has been validated by in situ data. Indeed, MERRA-2 and ALADIN fairly simulate the AOD with a maximum in March and June. However, these products tend to overestimate measurements, especially for ALADIN. The correlation coefficient between in situ AOD and products is evaluate almost 0.83 for MERRA-2 and 0.72 for ALADIN. From 2007 to 2009, dust deposition measurement campaign was conducted in Mbour. The comparison between these seasonal data and simulations show a right coherence even if MERRA-2 underestimates measurement and ALADIN overestimates it. The correlation compared to in situ measurements is estimate to 0.71 for MERRA-2 and 0.72 for ALADIN. However, the results showed that ALADIN better describes the seasonal dry deposition during dry season which lasts 9 months despite a strong overestimation in winter. Finally, long-term simulation with ALADIN show that dry deposition maximum occurs from December to May in Senegal and throughout the West Africa region.

An Internet of Things Infrastructure for Rainfall Monitoring in Dakar

Rainfall is a very important climatic phenomenon for the Sahelian economies. In Senegal, it has a very tremendous impact on agriculture and human life, which justifies the need for effective monitoring systems. In fact, the country has been experienced number of extreme events such as floods and public health problems. Despite the efforts made, it remains challenging to have real-time observations, which impact directly forecasts quality. In addition, systems used are not efficient and they are often expensive for implementation and deployment throughout the country. In this paper, we present an automatic rainfall station adapted. A prototype has been designed and implemented to ensure the reliability and availability of data in real time. In addition, a validation study is carried out in order to know its performances. For this, the designed prototype is installed on the same site near an approved industrial station, between July 1st and October 31st, 2017. The comparison between obtained results of these two stations is very satisfactory with a correlation of 99%.