Pastoralism is the dominant economy in the drylands of Kenya and Tanzania but up until recently there has been little appreciation of how pastoralists use environmental variability as a resource to maximise livestock productivity and mitigate asset loss. Paradoxically, far from being left behind by the rapid pace of developments in agriculture, these communities could be better prepared for the huge variations in rainfall, and the resultant threat to productivity, from climate change than their more settled agrarian peers.

Now an innovative pilot project in the two countries is showing a way to close the gap between local knowledge and distant government planning for policymakers grappling with how to adapt to climate change. A paper last year by the International Institute for Environment and Development and Southampton University’s Geodata Institute, Harnessing Pastoral Knowledge for Climate Change Adaptation in the Drylands, describes how a pioneering exercise in digital mapping is bridging the mutual incomprehension created by politicians and technocrats’ lack of understanding of pastoralism and the herders’ own inability in turn to explain their deep understanding of their environment.

Where conventional maps of these countries might show vast areas of empty, unproductive space in the drylands, crossed by an unpaved road here and a major watercourse there, pastoralists see land rich with resources and possibilities. To integrate the two contrasting visions of resources, the project first helps create a ‘community perception map’ in a village or pastoralists’ camp to allow as many people to participate. Different maps may be created depending on the informants: elders, women and youth.

A smaller group of key members of the community then meet for a workshop with local government planners and technical staff. Google Earth is projected on a wall next to the maps the community has prepared in the first consultation and the information is cross-referenced using the satellite imagery and open-source map editing applications to pinpoint the locations of the natural resources. These can then be independently verified.

Qualitative and quantitative data are entered on a spreadsheet with ID numbers to correspond to mapped features. This includes information on soil type, plant species and water quantity, details of land management and tenure systems, resources where access must be negotiated or paid, and areas of conflict. The accumulated data is then merged for use in a Global Information System. Crucially, the map that emerges goes back in turn for validation by the original participants—and those who might not have contributed to the initial stage. This ‘cross-pollination’, as the IIED/Geodata Institute report puts it, allows a consensus to form that adds authority to the finished map. It also elicits information that may otherwise remain known only to those reliant on those features, rather than those who might be able to enact change. For example, in Tanzania’s Longido ward it emerged during the digitisation process that 36 water points were in fact 143—and more than a quarter were not functioning.

Climate change exacerbates the structural causes of poverty and inequality, nowhere more so than in liminal environments such as the world’s arid rangelands. And there are few communities likely to be harder hit than those already struggling for resources in these harsher marginal territories, such as the nomads of east Africa, so it is heartening to see that the pilot projects are being pursued against a background of political and administrative devolution in Kenya and Tanzania and a more positive government approach to pastoralism. The digital maps could be the key to making the connections needed for such devolution to work.