The Kalahari Basin is a desert and sand dune area in southern Africa that includes the Kalahari Desert, is 2.5 million square miles in size, and covers parts of South Africa, Namibia, Botswana, and Zimbabwe. Temperatures in the basin reach 46 degrees Celsius or 115 degrees Fahrenheit and there is zero rainfall for six to eight months at a time. This makes for harsh conditions for indigenous as well as non-indigenous populations that rely heavily on agriculture, as well as hunting and gathering. Among the most vulnerable of these populations are the San people, also known pejoratively as the Bushmen. They are among the oldest tribes in the world and the oldest living population in Southern Africa – they are at least 20,000 years old. Africa as a continent is rated by the IPCC as one of the most vulnerable continents to climate change and specifically lists agricultural production and ecosystem change as major issues, two problems that are of particular importance to people living in the Basin. The Basin faces a range of impacts including sand dune expansion, loss of hunting due to drought, loss of native knowledge, and loss of arable agricultural land. The Basin is a prime example of many of the problems that the larger continent faces in regards to climate change.
One of the Oldest Tribes on Earth
To the right, two san women sit under a tree in the Central Kalahari Game Reserve. The San people say they are the first peoples to inhabit the Kalahari, and have lived in the area for 25,000 years. In addition to climate change vulnerability, the San people also face land rights issues, reliance on government, and a loss of traditional ecological knowledge that supports their semi-nomadic lifestyles.
Climate Change Hazards
Africa is among the most vulnerable continents to climate change. That vulnerability consists of high or very high confidence in the compromising of agricultural systems and the aggravation of water issues that many African countries are dealing with now. Ecosystem degradation and change is a bigger problem in the Southern Africa region, where the Kalahari Basin is located. Additionally, decadal warming changes are higher in South Africa (0.3 degrees) than in other regions, more rainfall anomalies and more stronger droughts have been reported since 1970 in the same region. A positive feedback loop is also occurring in Africa, whereby drought kills vegetation, however vegetation can contribute a possible 0.8 degrees of cooling. The more vegetation goes away, the hotter it gets, and then more vegetation dies off. One third of all Africans (approximately 400 million people) are living in drought prone areas, with many of those people located in or around the Kalahari Basin. Along with those 400 million, another one quarter of Africans live in high stress water areas, meaning their access to improved water is extremely variable and limited. Impacts from those stresses will be amplified by increased drought and higher temperatures and is considered by the IPCC to be especially sensitive to climate.
Table 9.1 in the IPCC report deals with significant ecosystem responses to climate change and specifically addresses the southern part of the Kalahari Basin. It details a scenario where all dune fields in the Basin are vulnerable to change or suffering from enhanced activity by 2099. This would lead to a decrease in fertile land for agriculture and a loss of traditional hunting patterns for hunter-gatherers. The IPCC briefly touches on indigenous knowledge systems in their Chapter nine Africa report, giving some space to indigenous models of forecasting the weather and observable changes in climate. However, most of the section on indigenous knowledge is dedicated to mitigation and adaptation, two facets of climate change not addressed here.
Climate Change on the Continent
Video by the World Health Organization
The Kalahari is mostly desert, and is expanding rapidly. The BBC reports that it could double in size to five million square miles. The article states that if wind speed increases to 15 miles per hour, it will disrupt grains enough to shift entire dunes. The wind speeds would be a result of warmer air coming in over the desert. This in turn covers agricultural land and covers the soil. A lack of cultivatable land will lead to a decrease in traditional farming practices for the 40% of Botswana’s residents (the Kalahari covers most of Botswana) that rely primarily on pastoral agriculture. David Thomas at the University of Oxford declared the journal Nature that all models show increase dune activity by 2070, meaning it is an unavoidable impact of climate change. While Thomas said this could result in more hunting and reliance on a non-sedentary lifestyle, that is also under threat from climate change. In addition to a possible loss of agricultural land and a direct impact on the economy, the Kalahari Desert is also a little known carbon sink. When higher temperatures and warmer air come in contact with the sand, there is a serious loss of carbon that is noticeable and comparable to other soils, according to Dr. Andrew Thomas of Manchester Metropolitan University. Although the release of stored carbon is traditionally associated with rich organic soil, this shows that shifting dunes and higher temperatures will also contribute significantly to what Thomas calls the global carbon dioxide budget.
Aside from the impact on the sand, climate change will also have unpredictable effects on birds and other species living in the Kalahari Basin, as extreme heat waves, drought, and rising temperatures “exceed the upper limits of organisms’ thermal tolerance” per the Hot Birds Programme run by the African Climate and Development Initiative. They confidently project a “range change” for birds that will come with increasing temperatures from climate change, and will be further studying what the physical response of the birds will be.
Vulnerability: The San People
Beyond the biological or physical impacts are the effects of climate change on vulnerable populations, such as the San people. The San people have lived in the Kalahari Basin for at least 20,000 years and have retained extensive native knowledge and nomadic practices during that time. However, they now number merely 50,000 tribesmen and are already losing battles for their native lands without the multiplying effects of climate change. The Central Kalahari Game Reserve has forced the San people off of their native hunting land and into settlements where they are trained to become herdsmen by government officials. Now, those 50,000 tribesmen and women are at risk of becoming climate refugees and in the hands of Botswana’s government, where they have not fared well in the past. They are considered the highest risk group in the area because of their dependence on the natural environment, a dependence that is becoming more restricted as climate change takes hold
Loss of Traditional Knowledge
The increased drought, unpredictability of water and loss of vegetation all make it harder for the San people to access their traditional resources. The unpredictable conditions also present challenges for indigenous knowledge, as they were able to use that knowledge to track animals, keep track of hunting seasons and sustainably manage the lands they hunted on. After what David Thomas said was hundreds of years of colonization, climate change is the latest challenge to the San people’s native knowledge. Additionally, it affects their freedom to move independently as a tribe. Normally the San people would have mapped out and passed along information as to where water sources are so that hunting groups could find them. Now, the drought and unpredictability of extreme weather has forced the San people to be more reliant on stationary water sources in the form of water bores owned by the Botswanian government.