The reason of ‘pause’ or ‘faux pause’ in the pace of global warming over the last decade has ignited a huge debate among the scientists, questioning the validity and accuracy of climate change forecasts and climatic models.
After a long period of rapid rise in global temperature during most of the 20th century, the pace of global warming has slowed unexpectedly over the last 10-15 years.
This unexpected slowdown has forced scientists to find a correct explanation as well as understand the long-term consequences of this change.
A new study has showed that the so-called ‘pause’ or slowdown in the global warming pace is due to the decades-long natural variations in the temperatures of sea water, mainly in the Atlantic and Pacific oceans.
According to researchers, the decade-long ‘oscillations’ in the sea temperature have heavily changed the wind patterns and ocean currents and the condition is expected to prevail for years before actually undergoing a reverse.
The study authors said that the Pacific Ocean is currently in a cooling state and hence, contributing in masking the harmful effects of global warming which is caused by human.
Study co-author Michael Mann, a climatologist at Penn State, said, “In the next decade we will likely begin to see the flip side — instead of slowing global warming, this internal oscillation will likely add to global warming. If so, we are in for a rude awakening. The false pause may have lulled us into a ‘dangerous’ false complacency.”
The researchers behind the study concluded their findings on the basis of a new “semi-empirical” method, involving observational data and several climate model simulations.
Along with Mann, some of the other scientists participated in the study were climate modeler and meteorologist Sonya Miller, from Penn State, and environmental scientist Byron Steinman, from the University of Minnesota Duluth.
The Pacific and Atlantic multi-decadal oscillations or swings occur on a 50-70 years scale, the scientists said.
According to the study authors, the Atlantic Ocean swings were more dominant in the mid of the last century. On the other hand, the Pacific Ocean oscillation has dominated in recent decades in resulting into current cooling trend.
Ben Booth, a climate scientist of the national weather service of the UK, said that the effects of clouds and aerosols, which can possibly trap or reflect heat, are something that are often absent in many climate models.
The findings of the study were published on Thursday in the journal Science.