Category Archives: The Science

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4 November 2015, Stockholm Resilience Centre, Tipping points: A new landscape of global crises. Recent crises are increasingly global and follow new kinds of patterns in the past crises were often local and isolated. They left surrounding ecosystems and societies largely unaffected. This made aid and governance work easier.Today, crises are becoming more global in reach affecting more people and systems at the same time. In a recent study lead by Thomas Homer-Dixon and Brian Walker published in Ecology and Society with Centre researchers Oonsie Biggs, Anne-Sophie Crépin, Carl Folke, Garry Peterson, Johan Rockström, Will Steffen and Max Troell a framework to identify the causes, processes and outcomes of multiple interconnected crises which they term “synchronous failure” is proposed. A guide for understanding globally interconnected crises The framework shows how several stressors together can cause a crisis which can rapidly spread to become global in reach. “We have developed a framework for understanding how global crises may emerge,” says Biggs. “Our framework could be used as an initial guide for systematic analyses and identifying early-warning signals and measures for building social-ecological resilience. It can also support establishment of appropriate governance structures that can navigate the danger of synchronous failure,” she says. Causes of crises The authors argue that future crises will increasingly result from three long-term global trends: the dramatic increase in human economic activity in relation to Earth’s environment, the rapidly increasing connections across the globe, and the decreasing diversity of human cultures, institutions, practices and technologies. These three trends create several stresses and reduce the capacity of systems to deal with disturbances. Case studies from the 2008 financial-energy and food-energy crises illustrate this. In the food-energy crises four stresses seemed to have affected the systems simultaneously, sometimes enhancing the impacts on one another:

1. diminishing supply of new agricultural land of good quality
2. declining returns on intensifying agriculture through more extensive inputs
3. climate change related extreme weather such as droughts
4. consistent high demand for food in a world with a growing population. Read More here

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4 November 2015, New York Times, The Tough Realities of the Paris Climate Talks. In less than a month, delegates from more than 190 countries will convene in Paris to finalize a sweeping agreement intended to constrain human influence on the climate. But any post-meeting celebration will be tempered by two sobering scientific realities that will weaken the effectiveness of even the most ambitious emissions reduction plans that are being discussed. The first reality is that emissions of carbon dioxide, the greenhouse gas of greatest concern, accumulate in the atmosphere and remain there for centuries as they are slowly absorbed by plants and the oceans. This means modest reductions in emissions will only delay the rise in atmospheric concentration but will not prevent it. Thus, even if global emissions could be reduced by a heroic average 20 percent from their “business as usual” course over the next 50 years, we would be delaying the projected doubling of the concentration by only 10 years, from 2065 to 2075. This is why drastic reductions would be needed to stabilize human influences on the climate at supposed “safe” levels. According to scenarios used by the United Nations Intergovernmental Panel on Climate Change, global annual per capita emissions would need to fall from today’s five metric tons to less than one ton by 2075, a level well below what any major country emits today and comparable to the emissions from such countries as Haiti, Yemen and Malawi. For comparison, current annual per capita emissions from the United States, Europe and China are, respectively, about 17, 7 and 6 tons. The second scientific reality, arising from peculiarities of the carbon dioxide molecule, is that the warming influence of the gas in the atmosphere changes less than proportionately as the concentration changes. As a result, small reductions will have progressively less influence on the climate as the atmospheric concentration increases. The practical implication of this slow logarithmic dependence is that eliminating a ton of emissions in the middle of the 21st century will exert only half of the cooling influence that it would have had in the middle of the 20th century. Read More here

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30 October 2015, Daily Science, Mass gains of Antarctic Ice Sheet greater than losses. A new study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers. A new NASA study says that an increase in Antarctic snow accumulation that began 10,000 years ago is currently adding enough ice to the continent to outweigh the increased losses from its thinning glaciers. The research challenges the conclusions of other studies, including the Intergovernmental Panel on Climate Change’s (IPCC) 2013 report, which says that Antarctica is overall losing land ice. According to the new analysis of satellite data, the Antarctic ice sheet showed a net gain of 112 billion tons of ice a year from 1992 to 2001. That net gain slowed to 82 billion tons of ice per year between 2003 and 2008. “We’re essentially in agreement with other studies that show an increase in ice discharge in the Antarctic Peninsula and the Thwaites and Pine Island region of West Antarctica,” said Jay Zwally, a glaciologist with NASA Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study, which was published on Oct. 30 in the Journal of Glaciology. “Our main disagreement is for East Antarctica and the interior of West Antarctica — there, we see an ice gain that exceeds the losses in the other areas.” Zwally added that his team “measured small height changes over large areas, as well as the large changes observed over smaller areas.” Read More here

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28 October 2015, Climate News Network, Rise in wildfires depletes forests’ carbon store. As the world warms, the increasing hazard of forest fires is dangerously tilting trees’ carbon storage balance from positive to negative in some regions of Alaska. In a warming world, forest fires could be about to put more carbon dioxide into the atmosphere than the trees absorb. New research by US scientists looked at decades of wildfire incidence in Alaska, and they have found that at least one region is now a net exporter of carbon. This is a reversal of the normal arrangements, whereby trees photosynthesise tissue from the carbon dioxide in the atmosphere. As they absorb carbon, they sequester it in roots, timber and leaves, and then in leaf litter in the forest soils. Fire is a natural hazard, and some geographical zones –the Mediterranean, the US southwest, and Australia – are adapted to periodic fire. But as the planet warms, there have been increasing levels of fire even in therainforests of the Amazon and in the boreal forests of the near-Arctic. Read More here