After all the doomsday talk on climate change, what if someone told you that the situation is still gloomy but not bleak as we have believed for some years now?
After all the doomsday talk on climate change, what if someone told you that the situation is still gloomy but not bleak as we have believed for some years now? An analysis published in Nature Geoscience earlier this month argues that it may be easier to contain Earth’s warming under 1.5oC above pre-industrial levels than it was thought before. The researchers focus on the fact that global climate models used in the 2013 report of the Intergovernmental Panel on Climate Change overestimate the extent of warming that has already happened. The researchers say that, 2015 onwards, humanity has had the space to emit almost three times the greenhouse gases (GHGs) than what was estimated by the Intergovernmental Panel on Climate Change (IPCC) even as the rise is held below 1.5oC.
They arrived at this after factoring the overestimation of the warming that has already happened by the climate models used by the IPCC and running further models. They argue that aggressive action on GHGs other than carbon dioxide can yield even larger carbon space. The implications are significant. We stand at cross-roads. Policy can either focus on reducing GHG burden and securing the planet’s climate future or exhaust the space—in any case, given current human activity, mankind is set to use up the carbon space IPCC had said it had to keep rise under 1.5oC in a matter of few years. Many climate scientists have already said that keeping to 1.5oC ceiling now looks impossible. The leader of the latest study? He told Nature that the Paris goal is not impossible, but “very, very difficult”.
At the same time, the research has its fair share of sceptics. The criticism that has carried the most academic weight is that the analysis is flawed because it centres on a period of slower warming that began at the turn of the millennium and continued till 2014—a period that is called climate hiatus. Critics say the new study’s estimate for the amount of anthropogenic warming so far—0.93oC—could be artificially low because the calculations are based on human contribution at a “cooler” time. Nature quoted Ben Sanderson, a climate modeller at the National Centre for Atmospheric Research in Colorado, the US, as saying that while oceans and other heat sinks absorbed more carbon than they normally do in the climate hiatus period, natural processes will cause the heat to be transferred back to the atmosphere.
So, while the debate rages on—on whether we hit the 1.5oC ceiling sooner or later—two things become certain. One, climate change will always be an inexact science, with diverse interests driving different opinion, and that we have to choose whether we act in the interest of the planet or lull ourselves into whatever black swan opportunity has come by. It is important to remember we live in the times of Donald Trump.