Regional adaptions can cool heat extremes by up to 2-3 degrees

Melbourne: Climate engineering that modifies the properties of the land surface in highly populated regions and agricultural areas over Asia, North American and Europe may reduce extreme temperatures there by up to 2-3 degrees Celsius, a study suggests.

The modifications could include “lightening” buildings, roads and other infrastructure in high population areas and changing crops and engaging in no-till agricultural practices.

Unlike many other climate-engineering methods proposed to tackle climate change, many of these regional modifications have already been tested and proven to work, said researchers from the University of New South Wales in Australia.

Critically, this method has fewer risks compared with injecting aerosols into the atmosphere, they said.

“Extreme temperatures are where human and natural systems are most vulnerable. Changing the radiative properties of land helps address this issue with fewer side effects,” said Andy Pitman from the ARC Centre of Excellence for Climate Extremes.

“This research suggests that by taking a regional approach, at least in temperate zones, policy and investment decisions can be pragmatically and affordably focused on areas of greatest need,” said Pitman.

By contrast other proposed forms of large-scale climate engineering, such as spraying sulphate aerosols into the atmosphere, fertilising the ocean with iron and even building giant mirrors in space, have questionable effectiveness and are likely to alter climate systems in unexpected ways.

They could make situations worse for some countries, the researchers said.

They gained their results by modelling how changing only the radiative properties of agricultural land and high population areas across North America, Europe and Asia would impact average temperatures, extreme temperatures and precipitation.

The results showed small impacts on average temperatures, little change in precipitation – except in Asia – but significant reductions in extreme temperatures.