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Ocean Probes To Help Refine Climate Change Forecasting; 'Oceanography Is Risky; You Lose Things' by Underwatertimes.com News Service - August 5, 2011 17:43 EST LOS ANGELES, California -- A USC researcher has opened a new window to understanding how the ocean impacts climate change. Lisa Collins, environmental studies lecturer with the USC Dornsife College, spent four years collecting samples from floating sediment traps in the San Pedro Basin off the Los Angeles coast, giving scientists a peek at how much carbon is locked up in the ocean and where it comes from. Collins' research suggests that the majority of particulate organic carbon (POC) falling to the basin floor is marine-derived, not the result of runoff from rainfall. This means that the ocean off the coast of Southern California is acting as a carbon "sink" - taking carbon out of the atmosphere via phytoplankton and locking it up in sediment. Though estimates regarding the effect of carbon in the ocean already exist, her hard data can help climatologists create more accurate predictions of how carbon will impact global warming. What is unique about Collins' study is that it is not just a snapshot of POC falling, but rather a finely detailed record of four years of POC production, showing how much fell and when. "It's all tied to climate change," said Collins, who started the research as a graduate student working for USC Earth Sciences Professor Will Berelson. "This lets us see patterns. "Our data can help climate modelers better predict the interactions between the oceans and atmosphere with respect to carbon which can help them better predict how much carbon dioxide will end up sequestered over the long term as sediments in the ocean," she said. Collins' study is among the longest of its kind in the region. A similar study was conducted in Santa Monica Basin from 1985-1991, and another is currently underway in Hawaii. Her findings appear in the August issue of Deep-Sea Research I. Between Janua

Science 25 November 2011: Vol. 334 no. 6059 p. 1039 DOI: 10.1126/science.334.6059.1039-b * News of the Week Random Sample Mongolia's 'Ice Shield' Figure View larger version: * In this page * In a new window Hot zone. Flanked by desert, Ulan Bator will be cooled in summer by an "ice shield." "CREDIT: BRÜCKE-OSTEUROPA/WIKIPEDIA" As the coldest capital on Earth, you might think the last thing Ulan Bator needs is more ice. But that is just what it's about to get under a geoengineering trial aimed at "storing" freezing winter temperatures to cool and water the city during the summer. At the end of this month, engineers will drill a series of bores through the ice on the Tuul River, pump up water from below, and spray it on the surface where it will freeze. This process will be repeated throughout the winter, adding layer after layer to create a chunk of ice that will be 7 or 8 meters thick by the spring. It's an attempt to artificially create the ultra-thick slabs-known as naleds in Russian-that occur naturally in far northern climes when rivers or springs push through surface cracks. Nomads have long made their summer camps near such phenomena, which melt much later than normal ice. Flanked by desert and plagued by summer temperatures that can rise close to 40°C, Ulan Bator's municipal government hopes the $724,000 experiment will create a cool microclimate and provide fresh water as the naled melts. ECOS & EMI, the Anglo-Mongolian company behind the plan, has still greater ambitions. "Everyone is panicking about melting glaciers and icecaps, but nobody has yet found a cheap, environmentally friendly alternative," says Robin Grayson, a geologist in Ulan Bator for ECOS & EMI. "If you know how to manipulate them, naled ice shields can repair permafrost and build cool parks in cities." The process, Grayson says, can be replicated anywhere where winter temperatures fall below −5°C for at least a couple of months.

"Stephanie Keske does computer visualization work, and is starting a graduate program this fall at Texas A&M University. She told me, "Just living on a ship, I think … you know, I try to be outside as much as I can so just being trapped on a floating hunk of metal is maybe going to be a little difficult. I don't know: I've never been in one place with an inability to leave it for 2 months solid." At the moment, Keske's in the northeast Pacific onboard an oceanographic research vessel. She and six other educators and artists from the US and France are working with the science team to do unprecedented outreach. Have a listen."

Mountains out of Molehills

Aerosols Altered Asian Monsoons Summer monsoons provide much of the water for farming on the Indian subcontinent, but the pattern of rain shifted dramatically during the last half of the 20th century. In a study appearing online 29 September in Science, researchers pin the blame on soot and other aerosols from human activities. From 1951 to 1999, central-northern India became drier while Pakistan, northwestern India, and southern India got wetter. To determine whether these changes were due to natural variability or human interference (greenhouse gases or aerosols), climate scientists Massimo Bollasina, Yi Ming, and V. Ramaswamy of the Geophysical Fluid Dynamics Laboratory/NOAA in Princeton, New Jersey, compared the history of rainfall with simulations that singled out each climate "forcing" factor to observe its impact. Although greenhouse gases would have increased rainfall over north-central India, the aerosols, they found, caused the "very pronounced drying trend," Ming says. Here's why: Under normal conditions, the northern hemisphere receives more energy from the sun from June to September; that imbalance drives the ocean-atmosphere circulation that powers the monsoons. But atmospheric aerosols shaded the northern hemisphere relative to the southern hemisphere, altering the energy balance between the two-weakening the circulation and altering where the rain falls.

The bad news just got worse: A new study finds that reining in greenhouse gas emissions in time to avert serious changes to Earth's climate will be at best extremely difficult. Current goals for reducing emissions fall far short of what would be needed to keep warming below dangerous levels, the study suggests. To succeed, we would most likely have to reverse the rise in emissions immediately and follow through with steep reductions through the century. Starting later would be far more expensive and require unproven technology.

An animated Robert Krulwich chemistry lesson -- in five episodes.