Tag Archives: rainfall

Deaths attributed directly to climate change cast pall over penguins

Climate change is killing penguin chicks from the world’s largest colony of Magellanic penguins, not just indirectly – by depriving them of food, as has been repeatedly documented for these and other seabirds – but directly as a result of drenching rainstorms and, at other times, heat, according to new findings from the University of Washington.

Too big for parents to sit over protectively, but still too young to have grown waterproof feathers, downy penguin chicks exposed to drenching rain can struggle and die of hypothermia in spite of the best efforts of their concerned parents. And during extreme heat, chicks without waterproofing can’t take a dip in cooling waters as adults can. (more…)

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Biologists find an evolutionary Facebook for monkeys and apes

Why do the faces of some primates contain so many different colors — black, blue, red, orange and white — that are mixed in all kinds of combinations and often striking patterns while other primate faces are quite plain?

UCLA biologists reported last year on the evolution of 129 primate faces in species from Central and South America. This research team now reports on the faces of 139 Old World African and Asian primate species that have been diversifying over some 25 million years. (more…)

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If a tree falls in Brazil…? Amazon deforestation could mean droughts for western U.S.

In research meant to highlight how the destruction of the Amazon rainforest could affect climate elsewhere, Princeton University-led researchers report that the total deforestation of the Amazon may significantly reduce rain and snowfall in the western United States, resulting in water and food shortages, and a greater risk of forest fires.

The researchers report in the Journal of Climate that an Amazon stripped bare could mean 20 percent less rain for the coastal Northwest and a 50 percent reduction in the Sierra Nevada snowpack, a crucial source of water for cities and farms in California. Previous research has shown that deforestation will likely produce dry air over the Amazon. Using high-resolution climate simulations, the researchers are the first to find that the atmosphere’s normal weather-moving mechanics would create a ripple effect that would move that dry air directly over the western United States from December to February. (more…)

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Hurricane research

Team studies new methods to support hurricane evacuation decision-making

Hurricanes are dynamic. Wind speeds change as the storm progresses and rainfall varies widely, creating tremendous uncertainty as the natural elements interact with man and man-made infrastructure.

Roads may close, traffic patterns may change, leading to travel delays that could impact lives and exacerbate public safety.

And yet researchers, policy makers and government officials have long relied on a static model to map hurricanes and chart evacuation zones, particularly when it comes to timing and decision-making.  (more…)

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Rainfall in South Pacific Was More Variable Before 20th Century

AUSTIN, Texas — A new reconstruction of climate in the South Pacific during the past 446 years shows rainfall varied much more dramatically before the start of the 20th century than after. The finding, based on an analysis of a cave formation called a stalagmite from the island nation of Vanuatu, could force climate modelers to adjust their models. The models are adjusted to match the current levels of climate variability that are smaller now than they were in the recent past for this region.

“In this case, the present is not the key to the past, nor the future,” says Jud Partin, a research scientist associate at The University of Texas at Austin’s Institute for Geophysics who led the study. The institute is part of the Jackson School of Geosciences. “Instead, the past is the key to what may happen in the future.” (more…)

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Mercury levels in Pacific fish likely to rise in coming decades

ANN ARBOR — University of Michigan researchers and their University of Hawaii colleagues say they’ve solved the longstanding mystery of how mercury gets into open-ocean fish, and their findings suggest that levels of the toxin in Pacific Ocean fish will likely rise in coming decades.

Using isotopic measurement techniques developed at U-M, the researchers determined that up to 80 percent of the toxic form of mercury, called methylmercury, found in the tissues of deep-feeding North Pacific Ocean fish is produced deep in the ocean, most likely by bacteria clinging to sinking bits of organic matter. (more…)

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Real-time Monitoring Pays Off for Tracking Nitrate Pulse in Mississippi River Basin to the Gulf of Mexico

Cutting edge optical sensor technology is being used in the Mississippi River basin to more accurately track the nitrate pulse from small streams, large tributaries and ultimately to the Gulf of Mexico.

Excessive springtime nitrate runoff from agricultural land and other sources in the Mississippi drainage eventually flows into the Mississippi River. Downstream, this excess nitrate contributes to the Gulf of Mexico hypoxic zone, an area with low oxygen known commonly as the “dead zone.” NOAA-supported researchers reported that the summer 2013 dead zone covered about 5,840 square miles, an area the size of Connecticut. (more…)

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Satellites See Double Jeopardy for SoCal Fire Season

PASADENA, Calif. – New insights into two factors that are creating a potentially volatile Southern California wildfire season come from an ongoing project using NASA and Indian satellite data by scientists at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.; and Chapman University, Orange, Calif.

The scientists tracked the relationship between rainfall and the growth and drying-out of vegetation in recent months, during an abnormally dry year. They found the timing of rains triggered regional vegetation growth in January and early February, which then dried out faster than normal during a period of low rainfall, strong winds and high temperatures in March and April. The combination likely elevates wildfire risks by increasing available fuel. (more…)

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