Examination of potential impacts of future climate change on solar radiation in Togo, West Africa

Abstract

This study investigates the potential impacts of future warming on Global Solar Radiation (GSR) in different parts of Togo, West Africa. It used regional climate simulations of the International Centre for Theoretical Physics version 4.7 (RegCM4) driven by HadGEM-ES and NorESM-M GCM for three different time-slice periods: baseline (1976–2005), near future (2031–2060) and far future (2070–2099). The models produced realistic simulations of GSR and temperature characteristics over the stations and the simulations spread are within the observation uncertainty. The simulations compared fairly well with the NASA observations. Biases in both the GSR (10–37 Wm−2 or 5–17%) and temperature (0.1–2.0 °C or 0.5–7.3%) were found to be insignificant at p < 0.05 across all the stations under investigation. The results revealed increasing but insignificant trends (0.025–0.043 °C year−1) in observed temperature but decreasing (0.225–0.567 Wm−2 year−1) in GSR during the baseline period. The estimated increasing trends (0.004–0.035% year−1) in cloud cover were partly attributed to the observed variations in surface GSR. All models projected increase in temperature (0.2–4.6 °C) but decrease in GSR (0.5–5.8%) over the entire country at both annual and seasonal time-scales. The simulated future changes in temperatures and GSR were expected to increase further and decrease, respectively, by the end of the century. The study has noteworthy implication in solar photovoltaic power production under warmer climate. It suggests a need for improved technology with the least climate change impacts over the republic of Togo, West Africa.