Rising temps, eroding buffer

Increasing temperatures are fostering more favorable conditions for the transmission of malaria into the highlands of Ethiopia, according to a study led by University of Maine associate research professor Bradfield Lyon.

Traditionally, the cooler climate in the highlands has provided a natural buffer against malaria transmission.

But new data indicate rising temperatures over the past 35 years are eroding this natural buffer and allowing conditions more suitable for malaria to climb into highland areas, says Lyon, who is based at the Climate Change Institute, and in the School of Earth and Climate Sciences.

 In 2015, the Centers for Disease Control and Prevention estimated 214 million cases of malaria occurred worldwide and 438,000 people died, mostly children in Africa.

The elevation at which the necessary temperature thresholds are met has risen by more than 100 meters since 1981.

“While a 100-meter increase may appear modest, we estimate that more than 6 million people currently live in areas with statistically significant increases in threshold temperature,” he says.

“The necessary temperature conditions for malaria transmission are now being met on an increasingly regular basis at higher elevations in the Ethiopian highlands, where a substantial population lives,” says Lyon.

The study, published in the journal Environmental Research Letters, utilized a newly developed national temperature data set for Ethiopia, made possible by NOAA’s Climate Program Office and Columbia University.