His doctoral research was on the Qoz region of Kordofan, Sudan, funded by the consultancy Huntings, with whom he had worked as a soil surveyor in Sind, West Pakistan after his undergraduate degree.
Warren's contributions are to the understanding of desert sand dunes, desertification in arid lands, and soil erosion by wind.
[1] This has proven controversial, but has helped shift the debate on desertification to one that recognizes dryland peoples as positive agents of change rather than destroyers of fragile ecosystems.
The team established that the region contributes substantially to global atmospheric dust due to its diatomite and mega-barchan dunes.
[5] The team also argued that dust, displaced into the upper atmosphere and widely dispersed, is a major contributor to terrestrial and oceanic nutrient budgets.