Met department underestimates Nairobi slum heat

Mathare slum in Nairobi. FILE photo | nmg
Mathare slum in Nairobi. FILE photo | nmg  

Densely packed housing and a lack of vegetation make temperatures in Nairobi slums much higher than those measured at the Kenya Meteorological Department’s headquarters in the capital city, US-based researchers reported on Monday.
Their study “suggests that climate change will hit people living in these ‘slum’ settlements harder because their living conditions often create a warmer ‘micro-climate’,” says an accompanying statement by Johns Hopkins University, the lead sponsor of the study.

Previous research by other scientists found that deaths among children younger than four and adults over 50 increase as temperatures rise above 20 degrees Celsius (68 Fahrenheit), the authors note.

During an 80-day period spanning 2015 and 2016, the average daytime high temperature recorded at the government’s Dagoretti observation station was about 25 degrees Celsius (78 Fahrenheit).

In Kibera, the average high in the same period was about 28 Celsius (82 Fahrenheit). And in Mathare and Mukuru — the other two settlements included in the study — the average was 29 Celsius (85 Fahrenheit) and 31 Celsius (87 Fahrenheit), respectively.

The Dagoretti station is located on a grassy, wooded campus less than a kilometre from Kibera.

The comparatively higher temperatures in the three slums are “certainly consistent with excess deaths,” said Johns Hopkins climate scientist Ann Scott, the study’s lead author.

A large proportion of Nairobi’s estimated 3.1 million residents live in poor settlements such as Kibera, Mukuru and Mathare, the researchers pointed out.

The study’s findings show that grass and trees help reduce temperatures, the Johns Hopkins statement says. The research also suggests that “as the Earth warms, the burden of climate change will not fall equally from one part of the planet to another.”

Because heat exposure is understood to be a function of population as well as temperature, “the burden of climate change is expected to be 100 times greater in Africa” where human numbers are rising far more rapidly than in less heated parts of the world, Johns Hopkins comments.

The University of Nairobi’s Department of Meteorology and the a climate-research unit of the Nairobi-based Intergovernmental Authority on Development were among the seven institutions that took part in the study.

The full study is published at the PLOS One (Public Library of Science) website.