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Drought May Stunt Forests' Ability to Grow for Years. Forests are sometimes called the lungs of the earth—they breathe in carbon dioxide in the atmosphere and store it in tree trunks until the forest dies or burns. A new study, however, shows that forests devastated by drought may lose their ability to store carbon over a much longer period than previously thought, reducing their role as a buffer between humans’ carbon emissions and a changing climate. The study, published Thursday in the journal Science by a team of by researchers at the University of Utah and Princeton University, shows that the world’s forests take an average of between two and four years to return to their normal growth and carbon dioxide absorption rate following a severe drought—a finding that has significant climate implications. “This means that these forests take up less carbon both during drought and after drought,” study lead author William Anderegg, an assistant professor of biology at the University of Utah and a researcher at Princeton University, said.

Journaldelenvironnement. Fossil fuels the 'new sub-prime crisis' Staggering gains in solar power - and soon battery storage as well - threatens to undercut the oil industry with lightning speed ... Writing in the conservative UK newspaper the Daily Telegraph, influential columnist Ambrose Evans-Pritchard writes that the "fossil industry is the subprime danger of this cycle". Oil and gas investment has soared and production has peaked but has yielded very little financial return: "The cumulative blitz on exploration and production over the past six years has been $5.4 trillion, yet little has come of it.

Output from conventional fields peaked in 2005. Mark Lewis of the leading European independent financial service, Kepler Cheuvreux states that "upstream costs in the oil industry have risen threefold since 2000 but output is up just 14%. " Bigger risks, collapsing rewards But the reality has been masked by big oil companies exploiting their cheap, more easily accessible reserves: Referencing a report by Carbon Tracker, Evans-Pritchard writes: Mysterious Craters Are Just the Beginning of Arctic Surprises. It's not just craters purportedly dug by aliens in Russia, it's also megaslumps, ice that burns and drunken trees. The ongoing meltdown of the permanently frozen ground that covers nearly a quarter of land in the Northern Hemisphere has caused a host of surprising arctic phenomena. Temperatures across the Arctic are warming roughly twice as fast as the rest of the globe, largely due to the reduction in the amount of sunlight reflecting off of white, snow-covered ground.

"At some point, we might get into a state of permafrost that is not comparable to what we know for 100 years or so, some new processes that never happened before," says geologist Guido Grosse of the Alfred Wegener Institute for Polar and Marine Research in Germany. The mysterious craters in far northern Russia are just such an example.

What We Know. Now the two most famous scientific institutions in Britain and the US agree: 'Climate change is more certain than ever' The speed of global warming is now 10 times faster than at the end of the last ice age, which represents the most rapid period of sustained temperature change on a global scale in history - and there is no end in sight if carbon emissions continue to increase, the Royal Society and the US National Academy of Sciences have warned. Concentrations of carbon dioxide in the atmosphere are the highest for at least 800,000 years and 40 per cent higher than they were in the 19th century. They are set to increase even further without a binding global agreement on significant cuts in industrial emissions, the scientists said.

Average global surface temperatures have increased by 0.8C since 1900 and the last 30 years have been the warmest in 800 years. On the current carbon dioxide trajectory, global warming could increase further by between 2.6C and 4.8C by 2100, which would be about as big as the temperature difference between now and the last ice age, they said. “The evidence is clear. Swiss wildlife climbing up the mountains - News in Brief. Animals and plants are already today adapting to the rising temperatures at a surprising pace.

Alpine ecosystems are on the rise. Between 2003 and 2010, plants have managed to scramble up another eight metres of mountain slope. On the way up, they were overtaken by butterflies, which collectively gained another 38 metres of higher ground. Alpine birds in turn fluttered an average of 42 metres higher. Tobias Roth and colleagues from the University of Basel and the Petite Camargue Alsacienne research station at St Louis in France report in PLOS One, the journal of the Public Library of Science, that, at least in the short term, alpine landscapes offer safe habitats in a warming world. "An average of eight metres difference in eight years and across all plant species is quite impressive for the often not very mobile plant communities", said Valentin Amrhein, one of the authors.

"The results show that the biological impacts of climate change will not only become apparent in the long term. To tackle inequality, the first priority is to fight climate change. When Bill de Blasio took the oath of office as mayor of New York City on 1 January, his inauguration address focused heavily on inequality. In a speech four weeks earlier, President Obama made reducing economic inequality a core mission, saying: "For the rest of my presidency, that's where you should expect my administration to focus all our efforts. " Inequality is a critical issue globally. A society where the gains of economic growth go only to the already wealthy is not stable. That said, I believe that when we look back on the priorities set by presidents and mayors at this time in history, people will be astonished at what our leaders didn't prioritise.

We should focus our energies on building general societal resilience (of which efforts to address inequality are a part), but more specifically, the first priority needs to be fighting and preparing for climate change. Imagine a probability curve of possible outcomes from our planet-baking experiment. As Temperatures Climb, So Does Malaria. Warming temperatures expand the risk area for malaria, pushing the disease farther uphill in afflicted regions, according to a new study. Infecting more than 300 million people each year, malaria emerges from a tapestry of temperature, rainfall, vectors, parasites, human movement, public health and economics. Fighting the disease involves pulling on all of these threads, but scientists have a hard time figuring out which ones are the most important to predicting where the disease will go.

Temperature has been especially contentious. Some previous research indicated that warmer weather only plays a minor role in this mosquito-borne illness, with human factors being the major influence on disease risk (ClimateWire, Feb. 4). Other studies concluded that climate change will cause no net increase in the disease in some parts of the world (ClimateWire, Sept. 20, 2013). The findings hold promise for better forecasting. But that doesn't account for where people reside relative to the disease. Stuck in the Antarctic ice we set out to study - Blogs. Going off the ship is an endeavour - the Antarctic equivalent of a spacewalk. It's cold, windy and lonely. Everything about it is the exact opposite of my normal summer destination. But scientists value the continent like an uncut gem. Every bit of data retrieved from Antarctica pushes science forward. Which is why just over a month ago, we set out on the Australasian Antarctic Expedition 2013. Our goal was a survey of the Southern Ocean near a place called Commonwealth Bay, which is unique because its conditions changed dramatically a few years ago.

Ice-free since 1912 Ever since Sir Douglas Mawson first arrived in Commonwealth Bay in 1912, the place has been ice-free and directly connected to the Southern Ocean in summer. But in 2010 a giant iceberg (B09B, almost 100km wide) ran aground in the middle of the bay and since then sea ice has been building up around the berg. Mawson's original Australasian Antarctic Expedition. Scientifically, the iceberg offers a wonderful opportunity. En Arctique, la glace la plus vieille fond et emporte le reste de la banquise avec elle.

La NOAA vient de publier une vidéo très efficace montrant combien les choses sont en train de dégénérer au sommet de la planète. Sur l'animation, on voit la fonte de la calotte glaciaire non seulement en termes de surface, mais aussi d'âge de la banquise – plus les zones sont blanches, plus les couches de glace sont anciennes (9 ans ou plus). On peut facilement constater que, ces dernières années, les couches de glace les plus anciennes ont fondu et que la glace arctique ne cesse de rajeunir. Ce qui n'augure rien de bon: plus la glace est vieille, plus elle est épaisse et plus elle reste en place; la glace plus jeune, elle, est plus fine et fond tous les étés. Ce qui signifie que, tous les ans, la quantité de glace présente au pôle nord diminue, et qu'elle diminue vite. A mesure que l'Arctique se réchauffe, sa capacité à former de la banquise, mais aussi à la conserver, s’évanouit. publicité Le problème ne se pose pas seulement en termes de surface, mais aussi de volume.

Phil Plait. L'activité solaire n'influence pas le changement climatique actuel. Les éruptions volcaniques seraient le forçage externe dominant sur la variabilité de la température globale moyenne. © Janke, USGS L'activité solaire n'influence pas le changement climatique actuel - 2 Photos L’activité solaire n’est peut-être pas l’un des acteurs majeurs dans les changements climatiques survenus au cours du dernier millénaire. Jusqu’à aujourd’hui, on attribuait communément le petit âge glaciaire (couvrant la période 1450-1850) à une faible activité de notre astre. De même, l’anomalie climatique médiévale, marquée par un réchauffement régional important durant la période 950-1250, est majoritairement associée à une intense activité solaire. Néanmoins, le lien entre l’intensité du soleil et l’amplitude du changement associé est méconnu. Beaucoup ont mis en exergue le fait qu'avant le petit âge glaciaire, l'activité solaire a été minimale durant 70 ans (c'est le minimum de Maunder).

L’influence du soleil sur les grandes ères climatiques est incontestable. Sur le même sujet.