News in Brief: Earth & Environment

The supercontinent of the future, pollutants from laundry detergent and more in this week’s news Web edition : Saturday, September 3rd, 2011

Clouds intensify soot’s Arctic heating
Reining in soot production could dramatically slow Arctic warming, Mark Jacobson of Stanford University reported August 31 in Denver at the American Chemical Society’s national meeting. Soot’s presence in water droplets heats clouds much more than it does the black carbon particles between cloud droplets, new computer analyses show — which Jacobson says “helps to explain the burning off of clouds in polluted regions.” Once clouds disappear, more sunlight reaches the surface to melt sea ice and warm Arctic waters. But curbing all soot that now wafts into the Arctic could within 15 years eliminate 15 to 20 percent of the total warming contribution to the region, which could reduce the net temperature rise by 50 percent, his computer projections indicate. —Janet Raloff

Bedrock can help the climate
Researchers from the University of California, Davis offer data that could overturn the conventional wisdom about where new nitrogen in land-based ecosystems comes from. It’s supposed to come from the atmosphere. But forests and local soils underlain with nitrogen-rich sedimentary rock contain 50 percent more nitrogen, a fertilizer, than do those atop nitrogen-poor rock, the scientists report in the Sept. 1 Nature. These researchers fingerprinted the bonus nitrogen to the weathering of bedrock below. Forests and soils over nitrogen-releasing rock also contained substantially more carbon than in nitrogen-poor areas, the scientists found, demonstrating that bedrock can dramatically boost the carbon-sequestering climate benefits of some forests. —Janet Raloff

Clean-smelling clothes dirty the air
Fragrance chemicals in detergents and dryer sheets can release toxic chemicals — none listed on product labels — especially into the air vented from a dryer. Anne Steinemann of the University of Washington in Seattle and her colleagues did laundry using no products, scented detergents, and detergents plus dryer sheets. The researchers report online August 19 in Air Quality, Atmosphere & Health finding substantial quantities of airborne organics including seven chemicals considered hazardous, two of which are potential carcinogens: acetaldehyde and benzene. Acetaldehyde measurements, if extrapolated to all users of the top five detergent brands throughout the county, could equal 6 percent of that toxic chemical’s releases from area cars if all the detergents produce the same levels the test detergent did, the researchers calculate. —Janet Raloff

Triggering earthquakes
Injecting carbon dioxide deep underground to keep it from entering the atmosphere can trigger earthquakes on local faults, a new study suggests. Scientists from the Lawrence Berkeley National Laboratory in California and the Côte d’Azur Observatory in France simulated what would happen if carbon dioxide entered an underground reservoir with a common kind of fault nearby. Depending on how and when the injection was done, an earthquake of up to magnitude 4.5 could occur, the team reports in a paper to appear in Geophysical Research Letters. Oil exploration, geothermal and other companies want to understand the conditions under which injections cause earthquakes. —Alexandra Witze

Supercontinent of the future
Continental drift, combined with heat from deep within Earth, could push North America, Eurasia, Australia and Africa together to form a new supercontinent in the Northern Hemisphere within the next 250 million years. Although scientists know about past supercontinents such as Pangaea, speculating about future landmasses has been something of a guessing game. Now, scientists in Japan have modeled heat welling up from Earth’s mantle and suggested exactly how that could drive today’s continents together. Antarctica and South America never join the future supercontinent, the team reports online August 17 in Terra Nova. —Alexandra Witze

Found in: Earth and Environment

View the original article here

News in Brief: Earth & Environment

The supercontinent of the future, pollutants from laundry detergent and more in this week’s news Web edition : Saturday, September 3rd, 2011

Clouds intensify soot’s Arctic heating
Reining in soot production could dramatically slow Arctic warming, Mark Jacobson of Stanford University reported August 31 in Denver at the American Chemical Society’s national meeting. Soot’s presence in water droplets heats clouds much more than it does the black carbon particles between cloud droplets, new computer analyses show — which Jacobson says “helps to explain the burning off of clouds in polluted regions.” Once clouds disappear, more sunlight reaches the surface to melt sea ice and warm Arctic waters. But curbing all soot that now wafts into the Arctic could within 15 years eliminate 15 to 20 percent of the total warming contribution to the region, which could reduce the net temperature rise by 50 percent, his computer projections indicate. —Janet Raloff

Bedrock can help the climate
Researchers from the University of California, Davis offer data that could overturn the conventional wisdom about where new nitrogen in land-based ecosystems comes from. It’s supposed to come from the atmosphere. But forests and local soils underlain with nitrogen-rich sedimentary rock contain 50 percent more nitrogen, a fertilizer, than do those atop nitrogen-poor rock, the scientists report in the Sept. 1 Nature. These researchers fingerprinted the bonus nitrogen to the weathering of bedrock below. Forests and soils over nitrogen-releasing rock also contained substantially more carbon than in nitrogen-poor areas, the scientists found, demonstrating that bedrock can dramatically boost the carbon-sequestering climate benefits of some forests. —Janet Raloff

Clean-smelling clothes dirty the air
Fragrance chemicals in detergents and dryer sheets can release toxic chemicals — none listed on product labels — especially into the air vented from a dryer. Anne Steinemann of the University of Washington in Seattle and her colleagues did laundry using no products, scented detergents, and detergents plus dryer sheets. The researchers report online August 19 in Air Quality, Atmosphere & Health finding substantial quantities of airborne organics including seven chemicals considered hazardous, two of which are potential carcinogens: acetaldehyde and benzene. Acetaldehyde measurements, if extrapolated to all users of the top five detergent brands throughout the county, could equal 6 percent of that toxic chemical’s releases from area cars if all the detergents produce the same levels the test detergent did, the researchers calculate. —Janet Raloff

Triggering earthquakes
Injecting carbon dioxide deep underground to keep it from entering the atmosphere can trigger earthquakes on local faults, a new study suggests. Scientists from the Lawrence Berkeley National Laboratory in California and the Côte d’Azur Observatory in France simulated what would happen if carbon dioxide entered an underground reservoir with a common kind of fault nearby. Depending on how and when the injection was done, an earthquake of up to magnitude 4.5 could occur, the team reports in a paper to appear in Geophysical Research Letters. Oil exploration, geothermal and other companies want to understand the conditions under which injections cause earthquakes. —Alexandra Witze

Supercontinent of the future
Continental drift, combined with heat from deep within Earth, could push North America, Eurasia, Australia and Africa together to form a new supercontinent in the Northern Hemisphere within the next 250 million years. Although scientists know about past supercontinents such as Pangaea, speculating about future landmasses has been something of a guessing game. Now, scientists in Japan have modeled heat welling up from Earth’s mantle and suggested exactly how that could drive today’s continents together. Antarctica and South America never join the future supercontinent, the team reports online August 17 in Terra Nova. —Alexandra Witze

Found in: Earth and Environment

View the original article here

News in Brief: Earth & Environment

Climate change brings a thirstier West and thinner polar bears, plus parsing the sun and moon's effects in this week's newsWeb edition : Saturday, June 11th, 2011

Polar bears' ice-melt diet

For polar bears, the loss of summer sea ice can be a slimming experience. The melting of ice floes eliminates resting spots and forces the bears to swim substantially more. One radio-tagged female lost a cub and almost one-quarter of her body weight over a roughly two-month period in late summer to early fall of 2008. Federal and university scientists from Alaska and Wyoming tracked her traveling almost 2,500 kilometers during that time, including one nine-day stint when she swam continuously — covering 687 kilometers. Such marathon travels would appear to compromise the health and fitness of this beleaguered species, the scientists argue in the July Polar Biology. —Janet Raloff

Celestial climate

The moon and the sun influence Earth’s climate at different times of year, a new study suggests. Researchers have analyzed month-to-month changes in the temperature gradient between the poles. The changes varied every 11 years in winter — meaning the sun was the driving force with its 11-year solar cycle — and 18.6 years in summer — meaning the moon dominated then. Basil Davis, of the École Polytechnique Féderal de Lausanne in Switzerland and Simon Brewer of the University of Wyoming in Laramie describe the work in an upcoming Quaternary Science Reviews. —Alexandra Witze

West may get much thirstier

The primary water source for the Colorado, Columbia and Missouri Rivers — and more than 70 million Americans — has been diminishing at a nearly unprecedented rate and breadth over the last half century, U.S. and Canadian researchers report. They analyzed tree-ring data going back 800 years in the Northern Rockies to reconstruct regional climate. Although precipitation rates seesawed through the centuries, snowpack shrinkage during the latter 20th century was the most dramatic, the scientists report in the June 9 Science. With temperature now appearing to outrank precipitation rates as the leading influence on water storage, the researchers say, current warming trends threaten Western water security. —Janet Raloff

Found in: Earth and Environment

View the original article here

News in Brief: Earth & Environment

Climate change brings a thirstier West and thinner polar bears, plus parsing the sun and moon's effects in this week's newsWeb edition : Saturday, June 11th, 2011

Polar bears' ice-melt diet

For polar bears, the loss of summer sea ice can be a slimming experience. The melting of ice floes eliminates resting spots and forces the bears to swim substantially more. One radio-tagged female lost a cub and almost one-quarter of her body weight over a roughly two-month period in late summer to early fall of 2008. Federal and university scientists from Alaska and Wyoming tracked her traveling almost 2,500 kilometers during that time, including one nine-day stint when she swam continuously — covering 687 kilometers. Such marathon travels would appear to compromise the health and fitness of this beleaguered species, the scientists argue in the July Polar Biology. —Janet Raloff

Celestial climate

The moon and the sun influence Earth’s climate at different times of year, a new study suggests. Researchers have analyzed month-to-month changes in the temperature gradient between the poles. The changes varied every 11 years in winter — meaning the sun was the driving force with its 11-year solar cycle — and 18.6 years in summer — meaning the moon dominated then. Basil Davis, of the École Polytechnique Féderal de Lausanne in Switzerland and Simon Brewer of the University of Wyoming in Laramie describe the work in an upcoming Quaternary Science Reviews. —Alexandra Witze

West may get much thirstier

The primary water source for the Colorado, Columbia and Missouri Rivers — and more than 70 million Americans — has been diminishing at a nearly unprecedented rate and breadth over the last half century, U.S. and Canadian researchers report. They analyzed tree-ring data going back 800 years in the Northern Rockies to reconstruct regional climate. Although precipitation rates seesawed through the centuries, snowpack shrinkage during the latter 20th century was the most dramatic, the scientists report in the June 9 Science. With temperature now appearing to outrank precipitation rates as the leading influence on water storage, the researchers say, current warming trends threaten Western water security. —Janet Raloff

Found in: Earth and Environment

View the original article here