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The decline in emissions also has negative implications

In large parts of Europe and North America, the decline in industrial emissions over the past 20 years has reduced pollution of the atmosphere and in turn of soils and water in many natural areas. The fact that this positive development can also have negative implications for these regions has been demonstrated by scientists at the Helmholtz Centre for Environmental Research (UFZ) in the journal Global Change Biology. According to their findings, declining nitrate concentrations in the riparian soils surrounding the tributary streams of reservoirs are responsible for the increasing release of dissolved organic carbon (DOC) and phosphate and a deterioration in water quality. In the case of drinking water reservoirs this can cause considerable problems with respect to water treatment.

Thawing ice makes the Alps grow

The Alps are steadily “growing” by about one to two millimeters per year. Likewise, the formerly glaciated subcontinents of North America and Scandinavia are also undergoing constant upward movement. This is due to the fact that at the end of the Last Glacial Maximum (LGM) about 18,000 years ago the glaciers melted and with this the former heavy pressure on the Earth’s surface diminished. The ice reacted rapidly to climate change at that time whereas the Earth’s crust is still responding today to this relatively sudden melting of ice. 

Efficient organic solar cells with very low driving force

It was believed that efficient operation of organic solar cells requires a large driving force, which limits the efficiency of organic solar cells. Now, a large group of researchers led by Feng Gao, lecturer at IFM at LiU, He Yan at the Hong Kong University of Science and Technology, and Kenan Gundogdu at the North Carolina State University have developed efficient organic solar cells with very low driving force.This implies that the intrinsic limitations of organic solar cells are no greater than those of other photovoltaic technologies, bringing them a step closer to commercialisation.

Urban Warming Slows Tree Growth, Photosynthesis

New research from North Carolina State University finds that urban warming reduces growth and photosynthesis in city trees. The researchers found that insect pests are part of the problem, but that heat itself plays a more significant role.

Researchers find better way to 'herd' electrons in solar fuel devices

Researchers at the University of British Columbia and the University of North Carolina at Chapel Hill have discovered a new way to optimize electron transfer in semi-conductors used in solar fuel solutions.The finding, published today in Nature Chemistry, could have a big impact on devices that convert sunlight into electricity and fuel.

NASA studies details of a greening Arctic

The northern reaches of North America are getting greener, according to a NASA study that provides the most detailed look yet at plant life across Alaska and Canada. In a changing climate, almost a third of the land cover – much of it Arctic tundra – is looking more like landscapes found in warmer ecosystems.With 87,000 images taken from Landsat satellites, converted into data that reflects the amount of healthy vegetation on the ground, the researchers found that western Alaska, Quebec and other regions became greener between 1984 and 2012. The new Landsat study further supports previous work that has shown changing vegetation in Arctic and boreal North America.

Shift in global winds caused record flooding in the Balkans

Disastrous floods in the Balkans two years ago are likely linked to the temporary slowdown of giant airstreams, scientists found. These wind patterns, circling the globe in the form of huge waves between the Equator and the North Pole, normally move eastwards, but practically stopped for several days then — at the same time, a weather system got stuck over Bosnia and Herzegovina, Serbia and Croatia that poured out record amounts of rain. The study adds evidence that so-called planetary wave resonance is a key mechanism for causing extreme weather events in summer. Further, the scientists showed that extreme rainfall events are strongly increasing in the Balkans, even more than the globally observed rise.”We were surprised to see how long the weather system that led to the flooding stayed over the region — it's like the Vb cyclone 'Yvette' was trapped there,” says Lisa Stadtherr from the Potsdam Institute for Climate Impact Research (PIK), lead-author of the study to be published in Science Advances. “Day after day the rain was soaking the soil until it was saturated, which lead to the flooding that reportedly caused several dozen casualties and 3.5 billion Euro of damages.” 

Snowshoe hare range moving northward following retreating snow cover

If there is an animal emblematic of the northern winter, it is the snowshoe hare.A forest dweller, the snowshoe hare is named for its big feet, which allow it to skitter over deep snow to escape lynx, coyotes and other predators. It changes color with the seasons, assuming a snow-white fur coat for winter camouflage.But a changing climate and reduced snow cover across the north is squeezing the animal out of its historic range, according to a new study by researchers at the University of Wisconsin-Madison. Writing in the current (March 30, 2016) Proceedings of the Royal Society B, the Wisconsin researchers report that the range of the hare in Wisconsin is creeping north by about five and a half miles per decade, closely tracking the diminishing snow cover the animal requires to be successful. 

Climate Change Redistributes Global Water Resources

Rising temperatures worldwide are changing not only weather systems, but – just as importantly – the distribution of water around the globe, according to a study published today (March 14, 2016) in the journal, “Scientific Reports.”Analysis of more than 40 years of water samples archived at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire tells a vivid tale of how the sources of precipitation have changed. Over the years, there has been a dramatic increase, especially during the winter, of the amount of water that originated far to the north.

Whales dine with their friends of the same species

For a few weeks in early fall, Georges Bank — a vast North Atlantic fishery off the coast of Cape Cod — teems with billions of herring that take over the region to spawn. The seasonal arrival of the herring also attracts predators to the shallow banks, including many species of whales.Now researchers from MIT, Northeastern University, the Institute of Marine Research in Norway, and the National Oceanic and Atmospheric Administration, have found that as multiple species of whales feast on herring, they tend to stick with their own kind, establishing species-specific feeding centers along the 150-mile length of Georges Bank. The team’s results are published today in the journal Nature.