Environment – Page 172 – Shamskm: A site to exchange knowledge and solutions

What’s so Unique About the Tropics?

By Guest PostSeptember 23, 2011Environment, Sciencebeta diversity, brad boyle, calgary, canada, costa rica, distribution of biodiversity across the globe, ecological mechanisms, ecologists, elevations in mountain regions, extinctions, geographical scales, latitudinal diversity gradient, nathan j b kraft, new zealand, northern europe, panama, south america, speciation, temperate forests of canada, tropical rainforests of southeast asia, tropics, university of arizona ecologist, university of british columbia, university of maryland

“Less than we thought,” researchers say in a new study providing insights into the distribution of biodiversity across the globe.

The temperate forests of Canada or Northern Europe may have much more in common with the tropical rainforests of Southeast Asia or South America than previously believed, according to a research group including a University of Arizona ecologist.

The assertion, published as the cover article in the journal Science, is focused on the concept of “beta-diversity” – a measure of the change in species composition between two sites, such as neighboring patches of forest. High beta-diversity means that two given sites have few species in common. (more…)

Deep Oceans May Mask Global Warming for Years at a Time

By Guest PostSeptember 22, 2011Environmentatlantic, climate system, community climate system model, computer simulations of global climate, coupled model intercomparison project phase 5, earth, el niño, eric deweaver, gerald meehl, global air temperatures, greenhouse gas, ice and snow, john fasullo, kevin trenberth, la niña, missing heat, national center for atmospheric research, ncar, oceanic circulation, rate of global warming, software tool, temperature, tropical pacific, warming the upper ocean

*Computer simulations of global climate lead to new conclusions*

Earth’s deep oceans may absorb enough heat at times to flatten the rate of global warming for periods of as long as a decade–even in the midst of longer-term warming. This according to a new analysis led by scientists at the National Center for Atmospheric Research (NCAR).

The study, based on computer simulations of global climate, points to ocean layers deeper than 1,000 feet as the main location of the “missing heat” during periods such as the past decade when global air temperatures showed little trend. (more…)

Arctic Sea Ice Reaches Minimum 2011 Extent, the Second Lowest in the Satellite Record

By Guest PostSeptember 19, 2011EnvironmentArctic, arctic ocean, Arctic sea ice, arctic sea ice extent, atmosphere, california, floating ice chunks, goddard space flight center, greenbelt, greenhouse gases, mark serreze, NASA, national snow and ice data center, sea ice, texas, university of colorado boulder, walt meier, warming temperatures

The blanket of sea ice that floats on the Arctic Ocean appears to have reached its lowest extent for 2011, the second lowest recorded since satellites began measuring it in 1979, according to the University of Colorado Boulder’s National Snow and Ice Data Center.

The Arctic sea ice extent fell to 1.67 million square miles, or 4.33 million square kilometers on Sept. 9, 2011. This year’s minimum of 1.67 million square miles is more than 1 million square miles below the 1979-2000 monthly average extent for September — an area larger than Texas and California combined. (more…)

Scorched Earth: The Past, Present and Future of Human Influences on Wildfires

By Guest PostSeptember 18, 2011Environmentearth, fires, human ignition, jennifer balch, pre human fire history, relative influences of climate, role of fire in natural ecosystems, sustainable fire management practices, university of california at santa barbara, western united states, wildfires

*A new framework for evaluating human influences on wildfires is developed*

Fires have continuously occurred on Earth for at least the last 400 million years. But since the 1970s, the frequency of wildfires has increased at least four-fold, and the total size of burn areas has increased at least six-fold in the western United States alone. Steadily rising, the U.S.’s bill for fighting wildfires now totals $1.5 billion per year.

How much of the increases in the frequency and size of fires are due to human activities? No one knows for sure. But a paper in this week’s issue of the Journal of Biogeography puts the role of fire in natural ecosystems into context and provides support for efforts to plan for future risks from wildfires. (more…)

Water Evaporated from Trees Cools Global Climate

By Guest PostSeptember 17, 2011Environmentatmosphere, central park, earth, emissions of carbon dioxide, evaporated water, evaporation, george ban-weiss, global balance of energy, global climate, global warming, govindasamy bala, greenhouse gas, julia pongratz, ken caldeira, new york, vegetation, water, water vapor

Washington, DC — Scientists have long debated about the impact on global climate of water evaporated from vegetation. New research from Carnegie’s Global Ecology department concludes that evaporated water helps cool the earth as a whole, not just the local area of evaporation, demonstrating that evaporation of water from trees and lakes could have a cooling effect on the entire atmosphere. These findings, published September 14 in Environmental Research Letters, have major implications for land-use decision making.

Evaporative cooling is the process by which a local area is cooled by the energy used in the evaporation process, energy that would have otherwise heated the area’s surface. It is well known that the paving over of urban areas and the clearing of forests can contribute to local warming by decreasing local evaporative cooling, but it was not understood whether this decreased evaporation would also contribute to global warming (more…)

MSU Scientists Suggest How Countries Can Cooperate on Climate

By Guest PostSeptember 16, 2011Environmentclimate change risk, climate policy, greenhouse gas mitigation, linear compensation

EAST LANSING, Mich. — When countries try to work together to limit the effects of climate change, the fear of being the only nation reducing greenhouse gas emissions – while the others enjoy the benefits with no sacrifice – can bring cooperation to a grinding halt. (more…)

Something Odd Is Happening With Namibia’s Weather

By Guest PostSeptember 16, 2011Environmentages of sediments, bedrock outcrops, drainage basins, river sediment, weather in namibia, western namibia

Southwestern African country is no arid desert–this year

Something’s up with the weather in Namibia, say geoscientists Kyle Nichols of Skidmore College in Saratoga Springs, N.Y., and Paul Bierman of the University of Vermont in Burlington, Vt. (more…)

New Video/Images of Walrus Haulout

By Guest PostSeptember 14, 2011Environment, Naturealaska, arctic basin, chukchi sea barrier beach, female walruses, human disturbance, icy cape, inupiaq community, native village of point lay, pacific walruses, point lay, radio tracking walruses, radio transmitters, sea ice, usgs alaska science center, walrus haulouts, walruses

ANCHORAGE, Alaska – The USGS Alaska Science Center has released new high-resolution video of Pacific walruses hauling out near Point Lay, Alaska, in late August, 2011.

Also available on the USGS Alaska Science Center walrus website are animations of the walruses’ movements as tracked by radio transmitters, and FAQs on the ongoing walrus studies. (more…)

Category Archives: Environment