Global warming's effect on extreme Indian Ocean Dipole: What it means for Africa

Flooding of the Gash River in Eastern Sudan, 2007. 
Credit: MOHAMED NURELDIN ABDALLAH/REUTERS

The CIRDA Team recently came across a paper in the weekly journal Nature discussing how global warming will likely impact an anomaly to the ocean/atmosphere circulation over the Indian Ocean (commonly known as the positive Indian Ocean Dipole or pIOD). By using various climate models that take into account an outlook with high GHG, the paper goes on to project that the frequency of high pIOD events will increase by almost three times.

What does this mean for Africa? For East Africa in particular the news is not good as major flooding events are likely to become much more common than in the past (increasing by a factor of 3 to 5 times). The potential for negative impacts on agricultue and infrastructure along rivers is very high. Prognoses like this increase the relevance of adaptation and access to climate information before these events occur in order to protect lives and assets and give end users such as farmers the necessary data they need to adapt. Programs like CIRDA are thus becoming more relevant and particularly urgent.

• Source: Wenju Cai, Agus Santoso, Guojian Wang, Evan Weller, Lixin Wu, Karumuri Ashok, Yukio Masumoto & Toshio Yamagata (2014) Increased frequency of extreme Indian Ocean Dipole events due to greenhouse warming (abstract) Nature 510, 254–258 (12 June 2014) doi:10.1038/nature13327