Global warming due to loss of large ice masses and Arctic summer sea ice

• Main Authors: Wunderling, Nico, Willeit, Matteo, Donges, Jonathan F., Winkelmann, Ricarda
• Format: Article in Journal/Newspaper
• Language: English
• Published: [London] : Nature Publishing Group UK 2020
• Subjects: carbon dioxide; albedo; anthropogenic effect; arctic environment; climate feedback; climate modeling; cryosphere; glacier mass balance; global warming; ice sheet; mountain environment; sea ice; summer; timescale; twenty first century; cloud; greenhouse effect; temperature; water vapor; Antarctic; Antarctica; Arctic; Greenland; West Antarctica; 500; West Antarctic Ice Sheet; Antarc*; glacier; Global warming; Ice Sheet; Sea ice
• Online Access: https://oa.tib.eu/renate/handle/123456789/10321; https://doi.org/10.34657/9357

Several large-scale cryosphere elements such as the Arctic summer sea ice, the mountain glaciers, the Greenland and West Antarctic Ice Sheet have changed substantially during the last century due to anthropogenic global warming. However, the impacts of their possible future disintegration on global mean temperature (GMT) and climate feedbacks have not yet been comprehensively evaluated. Here, we quantify this response using an Earth system model of intermediate complexity. Overall, we find a median additional global warming of 0.43 °C (interquartile range: 0.39−0.46 °C) at a CO2 concentration of 400 ppm. Most of this response (55%) is caused by albedo changes, but lapse rate together with water vapour (30%) and cloud feedbacks (15%) also contribute significantly. While a decay of the ice sheets would occur on centennial to millennial time scales, the Arctic might become ice-free during summer within the 21st century. Our findings imply an additional increase of the GMT on intermediate to long time scales. publishedVersion