Botswana to be hotter, drier
Anew research by the Botswana Institute for Technology Research and Innovation (BITRI) has projected that the county’s future climate will be hotter and drier. The climate projections show a decrease in annual total rainfall over the entire country as rainfall will start declining this spring from September to November and autumn, from March to May next year while a slight increase is anticipated to pick up during summer, from December to February.
The drying is pronounced mostly over the eastern half of the country, with the Kgatleng district leading. North East, Kgatleng and Central districts are projected to realise more than four percent and five percent decrease in annual rainfall at the two warming levels respectively.
The just ended research was conducted in 10 districts using the latest suite of high-resolution climate models and building upon existing research on climate projections, future climate scenarios of temperature and rainfall.
According to BITRI Associate Reseacher- Climate Change, Tiro Nkemelang, the results point towards a shift to the late onset and early cessation of the rainy season with potential increased intensity during the summer months.
“As a semi-arid country, Botswana is anticipated to warm faster than the global average.
Maximum temperatures are found to increase at a faster rate than mean and minimum temperatures especially during the September to November months,” he said.
At district level, the Kgalagadi and Gantsi districts are projected to warm faster than the national average, while the Central and North East districts are projected to warm at a slightly lower rate than the national average.
The unequal rate of warming starts to become pronounced when the global climate reaches the 1.5 warming level above pre-industrial levels.
Nkemelang also said the findings have significant policy implications, especially when looking at rainfall dependent sectors of the economy such as agriculture and water, highlighting that potential increased stress in these sectors require government and relevant stakeholders to formulate or revise existing policies to help Batswana better adapt to the future impacts.
“These include efforts to increase adoption of climate smart agricultural practices and addressing potential future water security challenges as cross sector to avoid hurting other sectors of the economy amongst others,” he said.
According to Nkemelang, a key finding of the study shows that care needs to be taken when defining future climate.
He said the conventional method that defines future climate by selected time periods, gives the impression that projected change will be much greater than when using the method prescribed in the 2015 Paris Agreement which can lead to costly maladaptation efforts.
The Paris Agreement is a legally binding international treaty on climate change.
It was adopted by 196 Parties at COP 21 in Paris, on December 12, 2015 and entered into force on November 4, 2016. Its goal is to limit global warming to well below two, preferably to 1.5 degrees celsius, compared to pre-industrial levels.