FEATHER IN CAP
would drop by 9%, with annual rainfall in Namibia dropping by 7%.
Both countries would also see an increase in dry days. At global warming of 1.5°C, projections show Botswana having 10 more dry days per year. That number rises to 17 extra dry days at 2°C global warming. For Namibia, dry days increase by 12 at global warming of 1.5°C, and by 17 at 2°C.
The impact of global warming on extreme events is also evident. Both countries can expect roughly 50 more days of heatwaves at 1.5°C global warming, and about 75 more days at 2°C.
In a hotter, drier future there will be less domestic water available. Runoff in Botswana’s Limpopo catchment is projected to decline by 26% at 1.50C global warming, and by 36% at 20C.
In Namibia, evapotranspiration rates increase by 10% at 1.50C global warming and by 13% at 20C, leading to reduced river flows and drier soils.
Agriculture is particularly vulnerable, with potential drops in crop yields and increased livestock losses. In Botswana, at 1.50C global warming maize yields could drop by over 20%. At 20C warming, yields could slump by 35%. Rain-fed agriculture is already marginal across much of the country, and anticipated climate change may well make current agricultural practices unviable.
In Namibia, productivity of cereal crops is expected to drop by 5% at 1.50C and 10% at 20C.
The impacts of global warming on human health are also essential to consider. Heat stress is projected to become an increasingly greater threat. At 1.50C of global warming, Namibia and Botswana can expect roughly 20 more days of heat stress exposure in a year. At 20C, in Namibia this doubles to around 40 more days.
All of these factors become even more severe should the 20C threshold be overshot.
The progressively serious climate impacts at 1.50C and 20C in these countries demands concerted action, both locally and internationally.
Leaders from countries such as Botswana and Namibia cannot let-up on the global stage in pushing for nation states to improve their pledges to cut greenhouse gas emissions in line with the Paris Agreement.
As the IPCC report shows, early action will not only reduce the risks of overshooting the Paris targets, but also slow down the rates of change, making local adaptation easier to roll out.
Republished from The Conversation.com