24 November 2015, The Conversation, Australia should back calls to end coal and save its drowning neighbours. While all of us of will experience the effects of climate change most are not facing the inevitable disappearance of our country. Yet that is the case for the 92,000 inhabitants of Kiribati, as well as other low-lying island states across the planet. With its nation dispersed over more than 20 islands, some increasingly subject to ocean flooding, the Kiribati government has purchased land in Fiji to relocate some of its inhabitants. Over the coming century Kiribati, along with every other maritime region, faces rising seas driven by oceans expanding as they warm, and by melting ice sheets and glaciers. Ahead of the Paris climate conference, which begins on November 30, Kiribati’s president Anote Tong has issued a call for a moratorium on new coal mines. On his recent visit to Melbourne I spoke to President Tong about the prospects for Kiribati in a warming world, and efforts to mitigate the worst impacts. End coal to saving drowning islands. President Tong related that his call for a coalmine moratorium has had a sympathetic hearing from US President Barack Obama. He and former Australian Prime Minister Tony Abbott talked amiably but (at best) agreed to disagree. As yet, he has been unable to meet with Abbott’s successor Malcolm Turnbull. What impressed me particularly is that, just as indigenous Australians relate to the land, President Tong was deeply passionate that the islands of Kiribati are the ancient, ancestral home of his people. President Tong however is under no illusion that anything will happen quickly when it comes to weaning the world off coal. He points out that coal-fired power stations will be needed in the medium-to-long term to heat the colder northern countries. Read More here
Category Archives: Ecosystem Stress
23 November 2015, Aljazeera, Siberia’s melting permafrost fuels climate change. Over the past year, a number of giant, mysterious holes have emerged in Siberia, some as deep as 200 metres. Scientists say the craters may be emerging because the frozen ground, or “permafrost”, that covers much of Siberia has been thawing due to climate change, allowing methane gases trapped underground to build up and explode. Permafrost is ground that is permanently frozen, where the ground temperature has remained below zero degrees Celsius for at least two years. It covers about a quarter of the northern hemisphere’s land surface. When permafrost thaws, microbes digest the plant and animal remains that were locked in the permafrost and release greenhouse gases, carbon dioxide and methane into the atmosphere. The phenomenon is a self-feeding cycle, explained Sarah Chadburn, from the University of Exeter. “Permafrost soils contain vast amounts of carbon, nearly twice as much as is currently in the atmosphere. As the permafrost thaws in a warming climate, the soil decomposes and releases carbon to the atmosphere as carbon dioxide and methane. These are greenhouse gases, and they warm the Earth even more. This leads to more permafrost thawing, more carbon release, and so the cycle continues,” Chadburn said. Read More here
18 November 2015, The Conversation, Shrinking Antarctic glaciers could make Adélie penguins unlikely winners of climate change. Penguin numbers exploded in East Antarctica at the end of the last ice age, according to research published today in BMC Evolutionary Biology. Despite their image as cold-loving creatures, the increase in Adélie penguin numbers seems to be closely linked to shrinking glaciers, raising the possibility the these penguins could be winners from current climate change. Adélie penguins are one of only two penguin species that live on the Antarctic continent. Their cousins, emperor penguins, may be the movie stars, but it is the Adélies that are the bigger players in the Southern Ocean. They outnumber emperors by more than ten to one, with a population of over 7.5 million breeding adults and counting. Given the abundance of Adélie penguins and their crucial role in Southern Ocean ecosystems, there has been a great deal of interest in understanding how the species is likely to respond to future climate change. Sensitivity to sea ice Breeding colonies have been monitored for decades to determine the effects of a changing environment on the penguins. A common finding of many of these studies is that Adélies are highly sensitive to sea ice conditions. Unlike emperor penguins, Adélies do not nest on the sea ice, but they must cross it to reach their nests on land. As everyone knows, penguins are not the most efficient walkers, and in years with a lot of sea ice their journeys to and from the ocean to feed their chicks can become lengthy. With a longer wait between meals chicks are less likely to survive. In an extreme case, extensive sea ice at one breeding colony had a devastating impact in 2014, and not a single chick survived. Read More here
17 November, ABC Science, New map of Earth’s groundwater to help estimate when it may run out. Less than 6 per cent of ground water in the upper two kilometres of the Earth’s landmass is renewable within a human lifetime, according to a new map showing the world’s hidden groundwater. “This has never been known before,” said the study’s lead author, Dr Tom Gleeson of the University of Victoria in Canada. “We already know that water levels in lots of aquifers are dropping. We’re using our groundwater resources too fast -faster than they’re being renewed.” Using data and computer models, an international group of hydrologists has produced the first data-driven estimate of the Earth’s total supply of groundwater. “Since we now know how much groundwater is being depleted and how much there is, we will be able to estimate how long until we run out.” The study, published in the journal Nature Geoscience, estimated a total volume of underground water to be almost 23 million cubic kilometres, of which 0.35 million cubic kilometres is younger than 50 years old. Underground water is found beneath the Earth’s surface and is recharged by rain, snow or water that leaks from the bottom of lakes and rivers. Its age can be a few months to millions of years. It can be found as deep as nine kilometres, according to the United States Geological Survey. “Since we now know how much groundwater is being depleted and how much there is, we will be able to estimate how long until we run out,” Dr Gleeson said. Read More here