NASA—How Tropical Rainforests May Help End the Climate Change Issue

If 2014 made anything evident on the global stage, it's that climate change is a serious issue and one that must be dealt with urgently. Many hope that the United Nations Summit in 2015 will bring some sort of international change, but with new research from the US space agency NASA, researchers are now saying that we may have some added help on our side-tropical rainforests.

With greenhouse gas emissions on a constant rise since the dawning of the industrial revolution and the subsequent population growth that followed, researchers in recent years have tried to estimate exactly how much carbon dioxide is actually absorbed by plants to better assess a serious global issue. And in a new NASA-led study, researchers from the Jet Propulsion Laboratory were able to combine three different divisions of science to reveal that tropical rainforests may be absorbing far more CO2 than many researchers previously thought, in response to rising atmospheric levels of the greenhouse gas.

While some CO2 is absorbed by "boreal forest" regions in Canada, Siberia and other northern regions densely covered in snow, the new study published in the journal Proceedings of National Academy of Sciences estimates that tropical forests absorb approximately 1.4 billion metric tons of the total global absorption of 2.5 billion metric tons per year.

"This is good news, because uptake in boreal forests is already slowing, while tropical forests may continue to take up carbon for many years," lead author of the study and researcher at NASA's Jet Propulsion Laboratory, David Schimel says.

Currently forests and other land vegetation remove up to 30 percent of carbon dioxide within our atmosphere during the process of photosynthesis. And this is of much aid in abating the issue of greenhouse gas emissions and climate change. Yet, it's not a perfectly efficient process. The researchers revealed that in response to the pressures exerted on the forests due to increased emissions courtesy of human pollution, trees are actually removing more and more carbon dioxide than ever before. Yet, should the limits of nature be pushed and should the rates decline, humans may find the Earth a far more inhospitable place with dwindling oxygen present and temperatures, courtesy of global warming, on the rise.

"It has big implications for our understanding of whether global terrestrial ecosystems might continue to offset our carbon dioxide emissions or might begin to exacerbate climate change" co-author of the study and researcher at the National Center for Atmospheric Research, Britton Stephens says. 

In an attempt to better assess the global issue and offer a unique view of the problems with greenhouse gases, the researchers devised a new method for direct comparison, blending three different areas of science into one study.

"The new study is the first to devise a way to make apples-to-apples comparisons of carbon dioxide estimates from many sources at different scales: computer models of ecosystem processes, atmospheric models run backward in time to deduce the sources of today's concentrations (called inverse models), satellite images, data from experimental forest plots and more" spokesperson from NASA's Earth Science News Team, Carol Rasmussen says. "The researchers reconciled all types of analyses and assessed the accuracy of the results based on how well they reproduced independent, ground-based measurements. They obtained their new estimate of the tropical carbon absorption from the models they determined to be the most trusted and verified."

Basing the combined data on the efficacy of each test, the researchers believe that their newest study reveals a view of the greenhouse gas issue never-before-seen, and shows how nature may be changing to better meet the needs of mankind.

"Until our analysis, no one had successfully completed a global reconciliation of information about carbon dioxide effects from the atmospheric, forestry and modeling communities," study co-author and JPL researcher, Joshua Fisher says. "It is incredible that all these different types of independent data sources start to converge on an answer."