What will happen if the glaciers in Antarctica melt because of the hole in the ozone layer?
Answers
The first comprehensive review of the state of Antarctica’s climate and its relationship to the global climate system is published this week (Tuesday 1 December) by the Scientific Committee on Antarctic Research (SCAR). The review - Antarctic Climate Change and the Environment – presents the latest research from the icy continent, identifies areas for future scientific research, and addresses the urgent questions that policy makers have about Antarctic melting, sea-level rise and biodiversity.
Based on the latest evidence* from 100 world-leading scientists from eight countries, the review focuses on the impact and consequences of rapid warming of the Antarctic Peninsula and the Southern Ocean; rapid ice loss in parts of Antarctica and the increase in sea ice around the continent; the impact of climate change on Antarctica’s plants and animals; the unprecedented increase in carbon dioxide levels; the connections between human-induced global change and natural variability; and the extraordinary finding that the ozone hole has shielded most of Antarctica from global warming.
Dr. Colin Summerhayes, Executive Director of the Scientific Committee on Antarctic Research said, “Antarctica is an unrivalled source of information about our planet. This review describes what we know now and illustrates how human activity is driving rapid climate change. By integrating this multidisciplinary evidence into a single source we will help scientists and policy makers understand the distinction between environmental changes linked to the Earth’s natural cycles, and those that are human induced. The work is particularly important because it puts Antarctic climate change into context and reveals the impact on the rest of the planet.”
Professor John Turner of British Antarctic Survey is the lead editor of the review. He said,“ For me the most astonishing evidence is the way that one man-made environmental impact – the ozone hole – has shielded most of Antarctica from another – global warming. Understanding the complexities surrounding these issues is a challenge for scientists – and communicating these in a meaningful way to society and to policymakers is essential. There is no doubt that our world is changing and human activity is accelerating global change. This review is a major step forward in making sure that the latest and best evidence is available in one place. It sets the scene for future Antarctic Research and provides the knowledge that we all need to help us live with environmental change.”
A summary of the report’s findings are detailed in the following 10 key points:
1. Hole in ozone layer has shielded most of Antarctica from global warming The ozone hole has delayed the impact of greenhouse gas increases on the climate of the continent. Consequently south polar winds (the polar vortex), have intensified and affected Antarctic weather patterns. Westerly winds over the Southern Ocean that surrounds Antarctica have increased by around 15%. The stronger winds have effectively isolated Antarctica from the warming elsewhere on the planet. As a result during the past 30 years there has been little change in surface temperature over much of the vast Antarctic continent, although West Antarctica has warmed slightly. An important exception is the eastern coast of the Antarctic Peninsula, which has seen rapid summer warming. This warming is caused by stronger westerly winds bringing warm, wet air into the region from the ocean.
2. Warming of the Southern Ocean wwill cause changes in Antarctic ecosystem The largest ocean current on Earth (the Antarctic Circumpolar Current) has warmed faster than the global ocean as a whole. The Southern Ocean is one of the major sinks of atmospheric CO2, but increasing westerly winds have affected the ocean’s ability to absorb CO2 by causing the upwelling of CO2 rich water. If temperatures continue to rise ‘alien’ species may migrate into the region, competing with and replacing original Antarctic inhabitants. Key species in the food chain like planktonic snailscould suffer from ocean acidification. Changes in the food regime are likely to decrease the rich Antarctic seabed biodiversity.
3. Rapid increase in plant communities across Antarctic Peninsula Rapid warming has been seen along the western Antarctic Peninsula, along with a switch from snowfall to rain during summer, resulting in expansion of plant, animal and microbial communities in newly available land. Humans have also inadvertently introduced ‘alien’ organisms such as grasses, flies and bacteria.