Tag Archives: pacific ocean

In ancient fish teeth, a tale of ecological resilience

Microscopic fish teeth may carry a message of hope from an ecological upheaval in the distant past, scientists at Yale University and the University of California-San Diego (UCSD) have found.

An analysis of tooth fossils and shark scales from the sea floor indicates that a massive die-off of species 66 million years ago did not, in fact, leave uniformly dead oceans around the world. In the Pacific Ocean, at least, some small fish species actually flourished. (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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Newly discovered ocean plume could be major source of iron

Study reveals micronutrient riches rising from the Southern Mid-Atlantic Ridge

Scientists have discovered a vast plume of iron and other micronutrients more than 1,000 km long billowing from hydrothermal vents in the South Atlantic Ocean. The finding, soon to be published in the journal Nature Geoscience, calls past estimates of iron abundances into question, and may challenge researchers’ assumptions about iron sources in the world’s seas.

“This study and other studies like it are going to force the scientific community to reevaluate how much iron is really being contributed by hydrothermal vents and to increase those estimates, and that has implications for not only iron geochemistry but a number of other disciplines as well,” says Mak Saito, a WHOI associate scientist and lead author of the study. (more…)

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2013 Summer Could be Similar to Last Summer, MU Researcher Says

Farmers should prepare for possible drought conditions through July

COLUMBIA, Mo. – Last summer, the Midwest experienced one of the hottest and driest summers on record. While a few rain showers have occurred across the Midwest the past few weeks, it appears that the region is in for another dry summer. A University of Missouri researcher says that an opposing weather pattern could bring more favorable weather conditions to the Midwest, but won’t be here until after this summer. (more…)

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Study Provides New Insights on Drought Predictions in East Africa

Research May Also Help Determine Effects of Global Warming in the Region

With more than 40 million people living under exceptional drought conditions in East Africa, the ability to make accurate predictions of drought has never been more important. In the aftermath of widespread famine and a humanitarian crisis caused by the 2010-2011 drought in the Horn of Africa—possibly the worst drought in 60 years— researchers are striving to determine whether drying trends will continue.

While it is clear that El Niño can affect precipitation in this region of East Africa, very little is known about the drivers of long-term shifts in rainfall. However, new research described in the journal Nature helps explain the mechanisms at work behind historical patterns of aridity in Eastern Africa over many decades, and the findings may help improve future predictions of drought and food security in the region. (more…)

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Plumes across the Pacific Deliver Thousands of Microbial Species to West Coast

A surprising number of microorganisms – more than 100 times more kinds than reported just four months ago – are leaping the biggest gap on the planet. Hitching rides in the upper troposphere, they’re making their way from Asia across the Pacific Ocean and landing in North America.

For the first time researchers have been able to gather enough biomass in the form of DNA to apply molecular methods to samples from two large dust plumes originating in Asia in the spring of 2011. The scientists detected more than 2,100 unique species compared to only 18 found in the very same plumes using traditional methods of culturing, results they published in July. (more…)

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New Research Underscores Vulnerability of Wildlife in Low-Lying Hawaiian Islands

HONOLULU, Hawaii — If current climate change trends continue, rising sea levels may inundate low-lying islands across the globe, placing island biodiversity at risk. A new U.S. Geological Survey scientific publication describes the first combined simulations of the effects of sea-level rise and wave action in the Northwestern Hawaiian Islands, offering the most detailed and multifaceted assessment available of how island biodiversity may be affected by climate change.

The publication, “Predicting Sea-Level Rise Vulnerability of Terrestrial Habitat and Wildlife of the Northwestern Hawaiian Islands,” by Michelle H. Reynolds, Paul Berkowitz, Karen N. Courtot, Crystal M. Krause, Jamie Carter, and Curt Storlazzi is available online. (more…)

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