Glaciers play a vital role in Earth’s climate system, and it’s critical to understand what contributes to their fluctuation.
Increased global temperatures are frequently viewed as the cause of glacial melt, but a new study of Patagonia’s Gualas Glacier highlights the role of precipitation in the glacier’s fluctuation. The study, conducted by Sébastien Bertrand of the Woods Hole Oceanographic Institution (WHOI) and his colleagues, reconstructs a 5,400 year-record of the region’s glacial environment and climate, comparing past temperature and rainfall data with sediment records of glacier fluctuations and the historical observations of early Spanish explorers. (more…)
Mesquite trees and woody shrubs are better adapted than grasslands to a Southwestern climate predicted to shift toward higher temperatures and greater variability in rainfall, UA ecologists have discovered.
As the desert Southwest becomes hotter and drier, semi-arid grasslands are slowly being replaced by a landscape dominated by mesquite trees, such as Prosopis velutina, and other woody shrubs, a team of University of Arizona researchers has found.
In a “leaf-to-landscape” approach, the team combined physiological experiments on individual plants and measurements across entire ecosystems to quantify how well grasslands, compared to mesquite trees and woody shrubs, cope with heat and water stress across seasonal precipitation periods. (more…)
How do we understand what’s happening today by looking back millions of years?
Scientists are looking at what climate conditions were like 3.3 to 3 million years ago, during a geologic period known as the Pliocene, and they are confident in the accuracy of their data.
The Pliocene is the most recent period of sustained global warmth similar to what is projected for the 21st century. Climate during this time period offers one of the closest analogs to estimate future climate conditions. (more…)
Researchers led by Matt Sullivan at the UA are among the first to dive into the world of viruses drifting through the world’s oceans.
Surrounded by the deep blue of the Pacific Ocean stretching from horizon to horizon, a lonely dot is glinting in the sun. It is the aluminum hull of a sailboat, a 118-foot schooner with white sails billowing from two masts.
On the deck, crewmembers and scientists are milling about. Commands are flying back and forth, and soon a strange contraption consisting of tubes clustered around an array of sensors dangling from a crane is lowered into the water, until it disappears in the clear blue depths. (more…)
EAST LANSING, Mich. — Underserved youth athletes report more life skill and character development when their coaches place greater emphasis on creating caring climates instead of focusing on competition, according to research from Michigan State University’s Institute for the Study of Youth Sports.
Playing in an atmosphere that focuses on player self-improvement versus player competition creates a sense of teamwork and develops initiative, social skills and a sense of identity, report the authors of the study from the Department of Kinesiology institute. (more…)
Nearly one-third of CO2 emissions due to human activities enters the world’s oceans. By reacting with seawater, CO2 increases the water’s acidity, which may significantly reduce the calcification rate of such marine organisms as corals and mollusks, resulting in the potential loss of ecosystems. The extent to which human activities have raised the surface level of acidity, however, has been difficult to detect on regional scales because it varies naturally from one season and one year to the next, and between regions, and direct observations go back only 30 years.
By combining computer modeling with observations, an international team of scientists concluded that anthropogenic CO2 emissions, resulting from the influence of human beings, over the last 100 to 200 years have already raised ocean acidity far beyond the range of natural variations. The study is published in the January 22, 2012 online issue of Nature Climate Change. (more…)
La Niña, “the diva of drought,” is peaking, increasing the odds that the Pacific Northwest will have more stormy weather this winter and spring, while the southwestern and southern United States will be dry.
Sea surface height data from NASA’s Jason-1 and -2 satellites show that the milder repeat of last year’s strong La Niña has recently intensified, as seen in the latest Jason-2 image of the Pacific Ocean, available at: https://sealevel.jpl.nasa.gov/images/ostm/20120108P1.jpg.(more…)
*Disruption of wind shear enables stronger storms*
Pollution is making Arabian Sea cyclones more intense, according to a study in this week’s issue of the journal Nature.
Traditionally, prevailing wind shear patterns prohibit cyclones in the Arabian Sea from becoming major storms.
The Nature paper suggests that weakening winds have enabled the formation of stronger cyclones in recent years–including storms in 2007 and 2010 that were the first recorded storms to enter the Gulf of Oman. (more…)
