This paper assessed the potential impacts of trends detected in rainfall, temperature and wind speed on hydro and wind power resources in Burundi. Two climatic stations located at two contrasting regions, namely Rwegura catchment and northern Imbo plain, were considered. Rainfall, temperature and wind speed observed data were considered for the period 1950–2014 and future projection data from seven Regional Climate Models (RCMs) for the period 2021–2050 were used. The interannual variability analysis was made using standardized variables. Trends and rupture were respectively detected through Mann–Kendall and Pettitt non-parametric tests. Mann–Whitney and Kolmogorov–Smirnov tests were considered as subseries comparison tests. The results showed a downward trend of rainfall while temperature and wind speed revealed upward trends for the period 1950–2014. All models projected increases in temperature and wind speed compared to the baseline period 1981–2010. Five models forecasted an increase in rainfall at northern Imbo plain station while four models projected a decrease in rainfall at Rwegura station. November was forecasted by the ensemble mean model to slightly increase in rainfall for both stations. Therefore, the country of Burundi may benefit more if it plans to invest in wind power.

This study assessed the rainfall trends and changes over Mono river basin under the highest greenhouse gas emission scenario RCP8.5. Simulations of eight regional climate models (RCMs) provided by Africa-CORDEX program were considered. To analyze the performance of a set of regional climate models, the MBE (mean bias error), the RMSE (root mean square error), the volume bias (VB), correlation coefficient (R 2) and the t-Test statistics were calculated. The precipitation concentration index (PCI), Mann-Kendall trend test, Theil-Sen's slope estimator (β), and relative percentage change methods were also adopted for data analysis. Changes from the baseline period 1981-2010 were computed for far future (2061-2090 and 2071-2100). As results, the analysis herein highlighted the multi-models' mean ability to simulate the Mono river basin rainfall adequately. Two distinct patterns emerged from the calculated PCI indicating that stations in southern basin will have moderate, irregular, and strongly irregular rainfall concentrations, whereas stations in northern basin will have irregular and strongly irregular rainfall concentrations. Significant declining in the rainfall was detected in most stations for the future period. The evolution of the monthly average rainfall amounts will be broadly characterized by a decrease and increase between 32.4 and 12% with late rainy seasons. It is understood that future changes in rainfall distribution and trends will affect the availability of water for crops, which should affect the productivity of rain fed agriculture.

This paper assessed climate change impact on future wind power potential across highlands and western lowlands of Burundi. Hourly observed and MERRA-2 data were considered for the historical period 1980-2016, and a Multi-model ensemble for future projections data of eight selected Regional Climate Models under RCP 4.5 and RCP 8.5 over the periods 2019-2040 and 2071-2100 was used. Variability and trend analysis were adopted using standardized index and Mann-Kendall's test, respectively while wind power density (WPD) in quartiles was adopted for changes distribution. As results, diurnal wind speeds (WS) were higher from 9:00 AM to 2:00 PM, while monthly wind speeds reached the maximum during summer time. An increasing trend in WPD was detected all over the studied area. Over the period 2019-2040, the lowest WPD change is projected at Northern Highlands (NHL) under RCP 4.5 with 28.04 W·m −2 while the highest WPD change of 47.35 W·m −2 is projected under RCP 8.5 at Southern Imbo plain (SIP). As for the period 2071-2100, the highest change is expected at SIP under RCP 8.5 with 152.39 W·m −2 while the minimum change of 83.96 W·m −2 is projected under RCP 4.5 at NHL. The findings showed that areas nearby the Lake Tanganyika are expected to have high positive WDP changes.

This study investigated the variability and trend of rainfall and extreme temperatures over three eastern and northeastern regions of Burundi during the period 1980-2015. Data used were collected from seven stations belonging to the geographical institute of Burundi. Annual and seasonal variability are assessed using standardized anomaly, coefficient of variance and precipitation concentration index. In addition, non parametric statistic tests Mann Kendall and Sen’s slope estimator are used to detect trends in rainfall, maximum and minimum temperatures. The results reveal a high monthly and inter-annual variability of rainfall whereas the temperature does not show high fluctuation at monthly scale. The northern region presents the lowest amount of rainfall for the first rainfall season (October-January) when drought is frequently observed. No significant rainfall trend detected over all regions at seasonal and annual scales whereas significant increasing trend was observed for both maximum and minimum temperatures over all regions. The spatial distribution of rainfall and extreme temperatures displays also a wide variation across the region depending on topography of the study area.