30-year African Rainfall Data to Improve Climate Models

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Map of African Rainfall. Image Source: Africa Environment Outlook.

Map of African Rainfall. Image Source: Africa Environment Outlook.

Within the next year, researcher David Grimes from the University of Reading in the United Kingdom plans to release a 30-year dataset measuring African rainfall. This open-access dataset will help predict long-term climate models and climate

A European Meteosat satellite that has been gathering data from Europe and Africa will be used to create the dataset. Previously, short-term predictions of climate models were possible, but no reliable long-term prediction set was available. For example, the Global Precipitation Climatology Project measured rainfall from different periods using different methods of calculation, making it more difficult to detect a climate pattern.

Grimes said in an article for SciDev.net, “Some models predict an increase in rainfall in some areas, other models predict a decrease of rainfall in the same area, and part of the reason for that is that data coming out of Africa [are] very poor and very sparse.”

Similarly, ground-based data acquisition in Africa is poor and tends to be contradictory. These satellite datasets will be calibrated to ground-based data in order to improve accuracy, since satellites can only provide estimates of rainfall and not exact amounts.

These climate predictability models have shown that Africa will be subjected to more extreme weather in the future. Researchers predict, for instance, that there will be recurrences of disasters such as the drought in the Horn of Africa in 2011, which caused a food crisis for more than 12 million people in countries such as Somalia, Ethiopia, and Kenya. Likewise, research predicts an increase in the risk of floods that predominate in countries in Southern Africa. Geoff Pegram, emeritus professor at the University of KwaZulu-Natal in South Africa, has released a statement saying that he believes droughts will be extremely dry and rainfall will cause heavier flooding.

Horn of Africa Drought. Image Source: UNICEF.

Horn of Africa Drought. Image Source: UNICEF.

Previous datasets could not predict rainfall in individual locations. However, this new 30-year dataset promises to make predictions with increased accuracy compared to ground-based data. Grimes explains that this new data can specify particular locations where the rainfall will be severe or mild, and predict such things as: What time of the year or season will be most intense, whether the rainfall is a change from the past 30 years, and whether it correlates with climate models.

Grimes will be establishing workshops in Africa to calibrate the data and teach on-site scientists how to analyze and interpret the information. He believes that Africa, next to Antarctica, is the most difficult continent to measure the distribution of rain gauges.

Tufa Dinki, a researcher at the International Research Institute for Climate and Society at Columbia University, notes that this dataset is unique. It uses a single algorithm and one satellite sensor to gather its data in order to promote consistency in the 30-year period.