Long-term analysis of rainfall and temperature data in Burkina Faso (1950-2013)

In this study, trends of classic climate indices on temperature and rainfall were combined with analyses of seasonal indices in order to better highlight the different angles of climate variability and change observed since 1950 in Burkina Faso. Results show that there is no doubt global warming affects all regions of the country. Concerning rainfall, the decrease of total annual precipitation proves to be the most significant change. This is consistent with results of other studies that focused on other areas of the sub-region. Despite this negative trend in all stations, this study demonstrates that the majority of stations have recorded a rainfall recovery in recent years. However, the rainfall levels recorded in 2013 are still far from what they were before the great droughts. The investigation of extreme events shows an overall stability in the frequency and in the intensity of these events. However, the conjunction of the general decrease of total rainfall, of the increase of average rainfall for wet days, of the increase of maximum consecutive dry days and of the decrease of maximum consecutive wet days proves that, even if there is not an increase in so-called heavy rains, there are changes in the pattern of rainfall. Because the results do not show a significant increase of extreme events, it is likely that the socioeconomic impacts generally presented as direct consequences of climate change and which are increasingly observed affecting inhabitants of Burkina Faso cannot be attributed to climate change alone.