Determining what global warming of 1.5°C and higher means for the semi-arid regions of Botswana, Namibia, Ghana, Mali, Kenya and Ethiopia: A description of ASSAR’s methods of analysis

Developing nations are the most vulnerable to the impacts of climate change. This is particularly true for semiarid regions (SAR) – climate change hotspots characterised by limited resources, remoteness, susceptibility to natural disasters, vulnerability to external shocks, and fragile environments. In these hotspots, an increase of just half a degree in global temperatures might have a significant effect, as seemingly-small temperature increments can lead to distinct climatological conditions at the local level.

In October 2018, the International Panel on Climate Change (IPCC) released a special report on the impacts of global warming of 1.5°C (IPCC, 2018) above pre-industrial levels – the target set by the Paris Agreement in 2015.

To coincide with this IPCC report, ASSAR developed a set of country-specific analyses that examine how projected 1.5°C and higher (half degree increments up to 3°C) global warming could affect temperatures, precipitation, and climate extremes within the semi-arid and arid regions of each of the African countries where ASSAR works, namely: Botswana, Ethiopia, Ghana, Kenya, Mali, and Namibia. We also explore how these local-level climate changes would impact on water, agriculture, health and other vulnerable sectors in these areas.

This working paper* describes how the analyses are done.

The timing of this work is critical as global temperatures could exceed the 1.5°C threshold by as early as 2026 (Henley and King, 2017). Other estimates indicate that in the absence of considerable emission reductions the world will cross the 1.5°C threshold around 2040. All estimates suggest an urgent need to accelerate locallevel adaptation responses. 

*Donwload the full text from the right-hand column.

Several datasets were analysed to understand what the impacts of 1.5°C is likely to be. This data analysis included:

• Calculating aridity zones
• Determining mean climate and extreme indices
• Calculating climate projections
• Determining local impacts 

Each of these steps is described in detail in the full text.

This methodology was used to produce the following infographics, which illustrate the likely impacts of 1.5°C across the study areas:

• What global warming of 1.5°C and higher means for Ghana
• What global warming of 1.5°C and higher means for Ethiopia
• What global warming of 1.5°C and higher means for Kenya
• What global warming of 1.5°C and higher means for Mali
• What global warming of 1.5°C and higher means for Botswana
• What global warming of 1.5°C and higher means for Namibia

Read more about ASSAR's work on the impacts of 1.5°C global warming here.