© 2003 Eugene S. Takle
Kerr (2003) gives a summary of an Science Express article by Giannini et al (2003) indicating that the 50-year warming trend in the Indian Ocean is likely the cause of the multi-year drought in the Sahel that began in the 1970s. Previous research had suggested land use in the Sahel region or global warming were the reason, but two separate modeling studies cited by Kerr (2003) pin the linkage to the Indian Ocean. These results do not, however, pin down the cause of the long term warming of the Indian Ocean. Possible candidates include increases in greenhouse gases or soot from combustion in China and India.
References
Kerr, R.A., 2003: Warming Indian Ocean wringing moisture from the Sahel.
Science, 302, 210-211.
Giannini, A.R.Saravanan, and P. Change. Oceanic forcing of Sahel rainfall on interannual to
interdecadal time scales. www.sciencexpress.org.