Tropical rainforests may be warming planet instead of fighting climate change: Study

New Delhi, Sep 18 (PTI) Important for fighting climate change, tropical rainforests could instead be contributing to the planet's warming by releasing vast amounts of carbon dioxide, potentially accelerating a feedback loop, according to a new study.

Considered critical in the world's fight against climate change, tropical rainforests are equipped with natural systems to absorb excess carbon and cool the planet.

However, a continued warming of the planet is causing soils of these forests to release enormous amounts of carbon dioxide, essentially flipping the script, researchers including those from the US' Chapman University said.

The study, published in the journal Nature Communications, looked at the rates of soil respiration in a Puerto Rican rainforest in response to a global warming of 4 degrees Celsius.

Findings show "soil respiration rates were 42-204 per cent higher in (experimentally) warmed (plots) relative to ambient plots, representing some of the highest soil respiration rates reported for any terrestrial ecosystem".

"This research shows that as the planet warms, tropical soils may begin to amplify that warming," author Christine Sierra O'Connell, Assistant Professor of Biological Sciences, said.

The study's results position belowground ecosystems as critical players in the global climate crisis, the researchers said.

The findings are also significant because soils store more carbon than the atmosphere and land plants combined, and soils releasing this carbon could amplify warming globally, they added.

"We are witnessing a troubling shift. The very systems we rely on to stabilise the climate may now be pushing us in the opposite direction," O'Connell said.

"If these patterns persist across time and regions, we may be drastically underestimating the extent to which tropical forests will lose carbon and accelerate climate change," the author added.

Tropical regions of the world are projected to experience the worst effects of climate change, should current trends in emissions and warming continue.

The researchers said that rainforests acting as carbon sources, instead of carbon sinks which absorb more carbon dioxide than they release, could accelerate global warming far faster than previously predicted.

This can affect everything from sea-level rise and extreme weather to food security and public health, the team said.

Understanding the feedback loop is essential if we are to prevent the worst impacts of a rapidly changing climate, they added. PTI KRS KRS KSS KSS