Bedrock of a holy city: the historical importance of Jerusalem's geology
Jerusalem's geology has been crucial in molding it into one of the most religiously important cities on the planet, according to a new study.
By simulating gullies, geographers discover ways to tame soil erosion
Dead zones in critical waterways, accelerated loss of arable land and massive famines. They're all caused by the 24 billion tons of soil that are lost every year to erosion, a phenomenon that costs the world as much as $40 billion annually.
Giant impact near India, not Mexico, may have doomed dinosaurs
A mysterious basin off the coast of India could be the largest, multi-ringed impact crater the world has ever seen. And if a new study is right, it may have been responsible for killing the dinosaurs off 65 million years ago.
Arctic now traps 25 percent of world's carbon... but that could change
The arctic could potentially alter the Earth's climate by becoming a possible source of global atmospheric carbon dioxide. The arctic now traps or absorbs up to 25 percent of this gas but climate change could alter that amount, according to a study published in the November issue of Ecological Monographs.
Climate models don't tell the full story
Climate models that predict heavy rainfall don't give the whole picture, according to the results of a study by NWO scientist Martin Ziegler. He examined climate changes that have taken place over the past 800,000 years, and discovered that the melting icebergs in the North Atlantic and changes in the El Niño Southern Oscillation have a great influence on the intensity of monsoon rains.
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Do dust particles curb climate change?
A knowledge gap exists in the area of climate research: for decades, scientists have been asking themselves whether, and to what extent man-made aerosols, that is, dust particles suspended in the atmosphere, enlarge the cloud cover and thus curb climate warming. Research has made little or no progress on this issue. Two scientists from the Max Planck Institute for Meteorology in Hamburg (MPI-M) and the American National Oceanic and Atmospheric Administration (NOAA) report in the journal Nature that the interaction between aerosols, clouds and precipitation is strongly dependent on factors that have not been adequately researched up to now. They urge the adoption of a research concept that will close this gap in the knowledge.
Princeton paleomagnetists put controversy to rest
Princeton University scientists have shown that, in ancient times, the Earth's magnetic field was structured like the two-pole model of today, suggesting that the methods geoscientists use to reconstruct the geography of early land masses on the globe are accurate. The findings may lead to a better understanding of historical continental movement, which relates to changes in climate.
Scientists measure the rate of ascent of volcanic magma
Plinian volcanic eruptions are notoriously destructive. These very powerful eruptions often occur after long periods of quiescence and are preceded by relatively short periods of seismic restiveness. Volcanoes that tend to show this kind of behaviour include Mount Vesuvius in Italy, Mt. Pinatubo in the Philippines and Mt. St. Helens in the USA. Professor Donald Dingwell of Ludwig-Maximilians-Universität (LMU) in Munich, together with Professor Jonathan Castro of the University of Orléans in France, has now been able experimentally to measure the speed with which molten rock rises during a Plinian eruption.
Coal-mining hazard resembles explosive volcanic eruption, study shows
Worldwide, thousands of workers die every year from mining accidents, and instantaneous coal outbursts in underground mines are among the major killers. But although scientists have been investigating coal outbursts for more than 150 years, the precise mechanism is still unknown.
Arctic bacteria: some like it hot
In subzero sediments off the island of Spitsbergen, scientists from the German Max Planck Institute for Marine Microbiology have detected high numbers of thermophilic (heat-loving) bacteria that are adapted to live in much warmer habitats. These thermophiles exist in the Arctic as spores - dormant forms that withstand adverse conditions for long periods, waiting for better times. Experimental incubations at 40 to 60 degrees Celsius revive the Arctic spores, which appear to have been transported from distant hot spots. The discovery could shed new light on one of microbiology's great hypotheses: "Everything is everywhere, but, the environment selects."
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