Earth Sciences
There has been a decline in the efficiency of natural land and ocean sinks which soak up carbon dioxide (CO2) emitted to the atmosphere by human activities, according to findings published this week in the Proceedings of the National Academy of Sciences of the US (PNAS).
The swift increase in atmospheric CO2 is due to faster economic growth coupled with a halt in carbon intensity reductions, in addition to natural sinks removing a smaller proportion of emissions from the air. Carbon intensity is the amount of carbon emitted to produce one dollar of global wealth.
The study’s lead author, Dr…
“Being a coral reef scientist these days can be depressing. So many reefs around the world have collapsed before our eyes in the past few years,” says Professor Terry Hughes, Director of the ARC’s Centre of Excellence for Coral Reef Studies. “But we’ve got to get past the gloom-and-doom, and use the best science to find practical ways to protect reefs from global warming.”
The world has a narrow window of opportunity to save coral reefs from the destruction caused by extreme climate change, according to a unanimous statement issued today by leading Australian scientists (see communiqué,…
Washington state climatologist Philip Mote, one of the lead authors of the recently released Fourth Assessment Report of the Intergovernmental Panel on Climate Change, will deliver a public lecture on global warming at the American Vacuum Society's (AVS) 54th International Symposium & Exhibition in Seattle. The lecture is free and open to the public (see details below).
“Climate change is real and it is a problem,” says Mote, a researcher with the University of Washington Climate Impacts Group. “It’s going to exacerbate all sorts of economic and environmental problems, and in the next few…
From 135,000 to 90,000 years ago tropical Africa had megadroughts more extreme and widespread than any previously known for that region, according to new research.
Learning that now-lush tropical Africa was an arid scrubland during the early Late Pleistocene provides new insights into humans' migration out of Africa and the evolution of fishes in Africa's Great Lakes.
"Lake Malawi, one of the deepest lakes in the world, acts as a rain gauge," said lead scientist Andrew S. Cohen of The University of Arizona in Tucson. "The lake level dropped at least 600 meters (1,968 feet) -- an…
Scientists are on the trail of Iapetus' mysterious dark side, which seems to be home to a bizarre 'runaway' process that is transporting vaporised water ice from the dark areas to the white areas of the Saturnian moon.
This 'thermal segregation' model may explain many details of the moon's strange and dramatically two-toned appearance, which have been revealed in exquisite detail in images collected during Cassini’s recent close fly-by of Iapetus.
Infrared observations from the fly-by confirm that the dark material is warm enough (approximately -146°C or 127 Kelvin) for very slow release of…
Why don't we know more about Lake Ellsworth? Because it's a frozen lake. Buried under two miles of ice. In Antarctica.
But Northumbria glaciologist Dr John Woodward, together with experts from the British Antarctic Survey and Edinburgh University, will spend five months working in sub zero conditions to unlock some of its secrets and discover what life may exist there.
More than 150 subglacial lakes have been identified in Antarctica, cut off from the outside world by thick caps of ice for tens or even hundreds of thousands of years. Any life forms will have had to adapt to complete…
The ozone hole over Antarctica has shrunk 30 percent as compared to last year's record size. According to measurements, this year’s ozone loss peaked at 27.7 million tons, compared to the 2006 record ozone loss of 40 million tons.
Ozone is a protective layer found about 15 miles above us, mostly in the stratospheric stratum of the atmosphere that acts as a sunlight filter shielding life on Earth from harmful ultraviolet rays. Over the last decade the ozone layer has thinned by about 0.3% per year on a global scale, increasing the risk of skin cancer, cataracts and harm to marine life.
The…
If space travelers ever visit Saturn's largest moon, they will find a tropical world where temperatures plunge to minus 274 degrees Fahrenheit, methane rains from the sky and dunes of ice or tar cover the planet's most arid regions. These conditions reflect a cold mirror image of Earth's tropical climate, according to scientists at the University of Chicago.
"You have all these things that are analogous to Earth. At the same time, it's foreign and unfamiliar," said Ray Pierrehumbert, the Louis Block Professor in Geophysical Sciences at Chicago.
Orange clouds (at lower center) on Saturn's…
This is a conceptual animation showing how polar ice reflects light from the sun. As this ice begins to melt, less sunlight gets reflected into space. It is instead absorbed into the oceans and land, raising the overall temperature, and fueling further melting.
NASA/Goddard Space Flight Center Conceptual Image Lab
Deluges of Biblical proportions were apparently not all that uncommon when glaciers were more prevalent in the Eurasian continent.
A glacier served as a natural dam for Siberian rivers and gigantic lakes were formed in northern Asia. In the mountains, glaciers formed dammed basins, which periodically burst and flooded vast territories, sending huge water and mud flows rushing out at the speed of 20 meters per second.
Researchers of the Irkutsk State University and Institutes of the Earth’s Crust and Geochemistry have recently discovered traces of a catastrophic hydrobreaking in the middle…