Environmental problems amplify human impact on Earth System

17 December 2019

Climate change, through increasing temperatures and changing rainfall patterns, has played a significant role in creating the conditions conducive for such massive and widespread fires.

The bushfires raging across Australia are a distressing example of connections between global environmental problems that amplify human impacts on the Earth System, says Dr Steven Lade from The Australian National University (ANU).

He and other authors, including ANU Emeritus Professor Will Steffen, write about this concerning phenomenon in Nature Sustainability, using the 'planetary boundaries' framework to analyse these connections.

One of the key interactions among the planetary boundaries involves climate change and land systems, an interaction the researchers say is playing out in disastrous fashion with the mega fires across eastern Australia.

"Climate change, through increasing temperatures and changing rainfall patterns, has played a significant role in creating the conditions conducive for such massive and widespread fires," said Dr Lade, an ANU Honorary Senior Lecturer who is based at Stockholm University.

"In turn, the bushfires are having an impact on the climate system by releasing large amounts of carbon dioxide into the atmosphere, contributing to further climate change in what scientists call a 'feedback loop'.

"In addition, smoke, unlike some other types of aerosols, also absorbs solar radiation, accelerating climate change even further.

"The severity of the fires coupled with ongoing climate change could lead to ecosystem shifts as the landscape eventually recovers. If new ecosystems store less carbon than the forests that were burnt, a long-term, net increase of carbon dioxide in the atmosphere will occur."

Dr Lade said immediate action to reduce greenhouse gas emissions is required to slow these damaging feedback loops and eventually stabilise the climate system.