The largest wilderness on Earth – Antarctica is also the most isolated continent. The oceans around Antarctica are some of the most pristine in the world with more than 8,000 marine species, more than half of which are seen nowhere else in the world.
However, this epic wonder is under pressure. Parts of the Antarctic are among the fastest warming places on the planet. The habitat and biodiversity are being impacted by climate change and human activities in the region such as pressures to increase krill fishing.
This week, WWF released a new report and iPAD app called Tracking Antarctica which dives into the science of Antarctica and the Southern Ocean and identifies ways the wonders of the region can be preserved for generations to come.
My name is Chris Johnson and I am a marine scientist at WWF-Australia and the editor of the report. I often see both interesting and important information that scientists spend years researching, buried deep in journals and reports that most people cannot access. So I spent the bulk of my career working in science communication trying to bring these stories from critical research to life.
Most people ask me – why does the Antarctic matter? Well, if the Amazon rainforest are the lungs of our planet then Antarctica and the Southern Ocean are its pulse. Its changing climate will guide and influence the rest of the planet. And, research tells us that the oceans surrounding Antarctica are warming, affecting worldwide heat and sea levels and have direct impacts on the climate worldwide.
A history in ice
While Antarctica provides many mysteries for scientists to solve, it has also contributed an important piece to the puzzle in our understanding of climate change – that is, how temperatures and greenhouse gases have changed over the centuries before observations began.
Thousands of years of the history of the Earth’s atmosphere is captured in tiny bubbles of air trapped in Antarctica. The deeper the bubbles, the older these perfectly preserved atmospheric time capsules are.
Scientists can extract the air from these bubbles by drilling ice cores, then measuring the amount of carbon dioxide and other gases in air up to a million years old. By chemically analysing the water, the temperature of the air is revealed at the time it was trapped.
The resulting records illustrate the comings and goings of ice ages, and warm periods such as the one we are now in. It’s clear from these long-term records that ice ages occur when there are low greenhouse gases concentrations in the atmosphere, and warm periods occur when there are higher levels. It is also clear that the level of carbon dioxide in the atmosphere today is higher than it has been for a million years. And, that is a concern.
Rising temperatures, rising seas – loss of sea-ice impacts animals great and small
Antarctica’s ice holds about 70 per cent of the world’s freshwater. If it ever all melted, it could raise global sea level more than 60 meters. That won’t happen any time soon, but even small changes in the balance between snowfall increases and melting ice losses will affect future sea level.
Ocean warming is affecting Antarctic krill – the mainstay for a range of marine species from the mighty Antarctic blue whale to the ambassadors of Antarctica – penguins. There are around 380 million tonnes of these shrimp-like crustaceans in the ocean, similar to the total weight of human life on the planet.
They live for about seven years and are no larger than a little finger. The role of Antarctic krill in supporting marine life might be more significant than that of any comparable species elsewhere in the world’s oceans. They are a critical food source for many Southern Ocean species such as whales, seals, fish, penguins and other seabirds.
Future ocean warming may cause a shift in krill habitat and ocean acidification may further
threaten krill as increased carbon dioxide levels interfere with hatching of and development krill larvae.
Antarctic krill occupy many different habitats: under sea ice, the surface water layer (0-10 meters) of the open ocean/sea-ice, the seafloor and the vertical water column between 200 m and the seabed. Krill larvae feed on microorganisms under the ice, so sea-ice reductions affect their survival from birth.
Changes in sea-ice is also the greatest immediate threat to Antarctic penguins
Climate change is likely to cause changes to sea-ice, leading to a continent-wide decline
and regional near extinction of emperor penguins by the end of this century. Paradoxically, increases in sea-ice cover in the East Antarctic region are forcing penguins to walk longer distances to reach the open sea to obtain food. Latest research shows a third of Adélie penguin colonies in Antarctica could disappear by 2060 due to the impacts of climate change.
Already, in the western Antarctic Peninsula, climate is influencing penguin distribution, most Adélie and chinstrap populations have declined, whereas gentoo populations have mostly increased.
More work to be done
Over the past year, I interviewed polar scientists and diving into the latest research in journals and reports to discover more about the Antarctic. I learned that there are solutions emerging from sound science.
Reducing our global emissions is critical to the survival of iconic species. In addition, establishing marine protected areas (MPAs) – like national parks on land – are a vital tool in delivering effective biodiversity conservation. In protected areas of the ocean, activities are managed, limited or entirely prohibited. MPAs can build resilience and mitigate regional climate change impacts ultimately improving the ecosystem and potential fisheries.
That is why I am here in Hobart, Australia. Over two weeks, 25 members are coming together for an international meeting called the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR). It’s like a mini-meeting of the United Nations with a critical task to implement grand scale conservation management initiatives. CCAMLR has committed to adopting marine protected areas (MPAs) in the waters around Antarctica.
Conserving Antarctic marine life is the objective of CCAMLR and it regulates fishing activities, considering all aspects of the ecosystem through consensus.
Global demand for fish meal and omega-3 supplements are likely to lead to increased krill fishing, which is increasingly concentrated along the Antarctic Peninsula and Scotia Arc [, particularly near the tip of the Peninsula ]. That’s why fishing for krill needs to be carefully watched and monitored by CCAMLR, not only limiting the amount fished, but the locations that may overlap with critical feeding areas for whales, seals, penguins, and other seabirds.
A few weeks ago, we saw incredible leadership at the Our Ocean Summit in the United States. Many countries and organisations stepped up to announce 136 new initiatives on marine conservation and protection valued at more than $5.24 billion, as well as new commitments on the protection of almost four million square kilometers (over 1.5 million square miles) of the ocean.
I am hopeful that history can be made here with science as a beacon in establishing marine protected areas in the Southern Ocean.
- Download a PDF version of the WWF Tracking Antarctica report
- WWF Tracking Antarctica app for iPAD and iPhone (6/7)
- NASA – Climate Change May Shrink Adélie Penguin Range By End of Century