Rapid Population Growth Among Causes of Recent Heavy Rains- Study

President William Ruto laying a stone on an affordable housing unit in Uasin-Gishu County.

The calamitous rains that pounded Kenya and broader East Africa from March to May were not just a stroke of bad luck.

An international team of climate scientists has now revealed that climate change, coupled with the rapid expansion of urban areas, has significantly intensified the impact of these rains, according to a study published Friday, May 24.

The findings from World Weather Attribution, a consortium of scientists specialising in analysing the influence of human-induced climate change on extreme weather events, paint a grim picture of the consequences of a warming planet.

The downpours unleashed floods that claimed hundreds of lives, displaced thousands, decimated livestock, and wiped out vast swathes of crops across the region.

To gauge the role of human activity in exacerbating floods, researchers meticulously scrutinised weather data and climate models. 

Their analysis focused on the regions hardest hit by the deluge, encompassing southern Kenya, most of Tanzania, and a portion of Burundi.

As of 17 May, an estimated 1.6 million people had fallen victim to the deluge, with a staggering death toll of 473 people and nearly 410,350 individuals forced from their homes.

Their alarming conclusion: climate change has rendered such devastating rains twice as likely and 5 per cent more intense. And the forecast doesn't offer solace — as temperatures climb, the frequency and intensity of these catastrophic rains are projected to escalate further.

A man stranded in the flooded Nairobi River.

"We're likely to see this kind of intensive rainfall happening this season going into the future," warned Joyce Kimutai, the lead author of the study and a research associate at Imperial College London.

The report bluntly states, "Taking these findings and the known physical relationship that heavy rainfall is expected to increase in a warming world, we conclude that the observed increase in rainfall in the region over the last 15 years is in part driven by human-induced climate change."

But climate change isn't the sole culprit. The rapid urbanization of East African cities is compounding the risk of flooding. 

Urban areas, especially densely populated informal settlements, bore the brunt of the deluge, laying bare the inadequacies of urban planning in coping with burgeoning populations and extreme weather events.

March to May marks the "long rains" season in East Africa, traditionally a period of intense downpours. 

However, the recent events have been far from normal. Prior to this, the region grappled with floods during the "short rains" of October to December 2023 and endured a prolonged three-year drought, both exacerbated by climate change, according to WWA scientists.

Philip Omondi, a climate change specialist at the IGAD Climate Prediction and Applications Centre in Nairobi, pointed out that intense and frequent extreme floods and droughts are being exacerbated by human-induced impacts.

In Nairobi, Shaun Ferris, a senior technical advisor for agriculture and climate change at Catholic Relief Services, emphasized the immediate necessity for resilient infrastructure capable of enduring the challenges brought on by climate change.

"There is huge pressure on basic services," Ferris emphasised, pointing to Nairobi's doubling population over the past two decades.

Ferris called for leveraging the loss and damage fund for climate disasters to repair and fortify basic infrastructure.

President William Ruto and Interior Cabinet Secretary Kithure Kindiki inspecting the demolishing of houses on riparian land along the Nairobi River, May 6.
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