Researchers caution that global warming signals are being masked by random weather variations and report that the human influence on snowfall levels will become detectable within the next few decades.
In a warmer world, scientists expect to see an increase in snowfall over the Antarctic because of higher levels of moisture in the air. This is expressed in global and regional climate models as an increase in surface mass balance (SMB) - a term that incorporates the loss of mass in the Antarctic ice sheet through sublimation and the gain in mass due to snowfall.
However, so far - and contrary to robust projections - observations have failed to detect any such increase in net snow accumulation in the region in recent times. Reporting their findings in the journal Environmental Research Letters, scientists in the US have looked into this discrepancy in more detail.
"The long-term SMB trend due to global warming in recent decades is small compared to the natural variability of SMB that arises from random, chaotic variations in the weather," explained Michael Previdi of Columbia University, who performed the study together with his colleague, Lorenzo Polvani. "As a result, these random weather variations could have effectively 'masked' the global warming signal, thus preventing any long-term SMB trend from being detected in the observations."
Their conclusions are based on the analysis of 35 different climate models, which allow the researchers to quantify i) the human influence on Antarctic SMB and ii) the natural variability of SMB that arises from random, chaotic variations in the weather.
"We believe that the human influence on Antarctic SMB will become detectable within the next few decades," said Previdi. "This is of critical societal importance since increases in snowfall in the region will have a mitigating effect on future global sea-level rise."
Full details on the work can be found in the open access journal Environmental Research Letters .
###
Notes to Editors
Contact
For further information, including the paper or spokesperson contact details, please contact:
Anastasia Ireland, Senior Marketing Executive, IOP Publishing
Tel 0117 930 1843
Email Anastasia.Ireland@iop.org
Philippa Skett, Media Officer, Institute of Physics
Tel 0207 470 4829
Email Philippa.Skett@iop.org
For more information on how to use the embargoed material, please refer to IOP Publishing's embargo policy ( http://ioppublishing.org/news/journalist-area/embargo-policy ).
Paper
The published version of the paper Anthropogenic impact on Antarctic surface mass balance, currently masked by natural variability, to emerge by mid-century" (Previdi and Polvani 2016 Environ. Res. Lett. 11 094001) will be freely available online 25 August. It will be available at http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094001 . DOI: 10.1088.1748-9326/11/9/094001.
About Environmental Research Letters
Environmental Research Letters covers all of environmental science, providing a coherent and integrated approach including research articles, perspectives and editorials. Go to http://iopscience.org/erl .
About IOP Publishing
IOP Publishing provides publications through which leading-edge scientific research is distributed worldwide. IOP Publishing is central to the Institute of Physics, a not-for-profit society. Any financial surplus earned by IOP Publishing goes to support science through the activities of the Institute. Go to http://ioppublishing.org or follow us on Twitter @IOPPublishing .
About the Institute of Physics
The Institute of Physics is a leading scientific society. We are a charitable organisation with a worldwide membership of more than 50,000, working together to advance physics education, research and application. We engage with policymakers and the general public to develop awareness and understanding of the value of physics and, through IOP Publishing, we are world leaders in professional scientific communications. Visit us at http://www.iop.org . Follow IOP on Twitter via @PhysicsNews.
Journal
Environmental Research Letters