The Earth is getting warmer at a faster rate than ever, in which oceans play a critical role. 93% of the net energy are absorbed by global ocean surface in the form of the Ocean Heat Uptake (OHU), which is the key factor modulating the rate of global warming.
The Earth is getting warmer at a faster rate than ever, in which oceans play a critical role. 93% of the net energy are absorbed by global ocean surface in the form of the Ocean Heat Uptake (OHU), which is the key factor modulating the rate of global warming.
Since 1850, the heat absorbed by oceans is increasing with stronger global warming. The Southern Ocean (surrounding the Antarctic continent, south of 30°S ) plays a dominant role in global OHU while the North Atlantic takes a small share. This phenomenon has been largely due to the concurrent increase in GHGs and aerosols during past centuries and related to changes in deep ocean circulations, in which strong thermohaline circulation in the Atlantic--the Atlantic Meridional Overturning Circulation (AMOC) plays a key role.
Future emissions of GHGs and aerosols in the 21st century will be different from those in the historical period (since 1850), according to a new study published in Science Advances on Nov 6, 2020. The article revealed the effects of aerosols and GHGs on regional OHU under different future warming scenarios. Based on the target of the 2015 Paris Agreement that limits global warming of 1.5°C or 2°C above pre-industrial levels by 2100, the new study first found the hemispheric asymmetry of OHU and its reasons under a low-emission scenario.
Read more at: Institute of Atmospheric Physics, Chinese Academy of Science
Cutting emissions makes the North Atlantic the focus of ocean heat uptake under global warming. (Photo Credit: Gang Huang)
