Tag Archives: fraction

Hydrologists Find Mississippi River’s Buffering System for Nitrates is Overwhelmed

AUSTIN, Texas — A new method of measuring the interaction of surface water and groundwater along the length of the Mississippi River network adds fresh evidence that the network’s natural ability to chemically filter out nitrates is being overwhelmed.

The research by hydrogeologists at The University of Texas at Austin, which appears in the May 11 edition of the journal Nature Geoscience, shows for the first time that virtually every drop of water coursing through 311,000 miles (500,000 kilometers) of waterways in the Mississippi River network goes through a natural filtering process as it flows to the Gulf of Mexico. (more…)

Read More

New Explanation for Slow Earthquakes on San Andreas

New Zealand’s geologic hazards agency reported this week an ongoing, “silent” earthquake that began in January is still going strong. Though it is releasing the energy equivalent of a 7.0 earthquake, New Zealanders can’t feel it because its energy is being released over a long period of time, therefore slow, rather than a few short seconds. 

These so-called “slow slip events” are common at subduction zone faults – where an oceanic plate meets a continental plate and dives beneath it. They also occur on continents along strike-slip faults like California’s San Andreas, where two plates move horizontally in opposite directions.  Occurring close to the surface, in the upper 3-5 kilometers (km) of the fault, this slow, silent movement is referred to as “creep events.” (more…)

Read More

Measuring the “Other” Greenhouse Gases: Higher Than Expected Levels of Methane in California

Berkeley Lab scientists develop new method for evaluating short-lived pollutants.

New research from Lawrence Berkeley National Laboratory (Berkeley Lab) has found that levels of methane—a potent greenhouse gas emitted from many man-made sources, such as coal mines, landfills and livestock ranches—are at least one-and-a-half times higher in California than previously estimated.

Working with scientists from the National Oceanic and Atmospheric Administration (NOAA) Berkeley Lab scientists Marc L. Fischer and Seongeun Jeong combined highly accurate methane measurements from a tower with model predictions of expected methane signals to revise estimated methane emissions from central California. They found that annually averaged methane emissions in California were 1.5 to 1.8 times greater than previous estimates, depending on the spatial distribution of the methane emissions. (more…)

Read More

Russian River Water Unexpected Culprit Behind Arctic Freshening

A hemispherewide phenomenon – and not just regional forces – has caused record-breaking amounts of freshwater to accumulate in the Arctic’s Beaufort Sea.

Frigid freshwater flowing into the Arctic Ocean from three of Russia’s mighty rivers was diverted hundreds of miles to a completely different part of the ocean in response to a decades-long shift in atmospheric pressure associated with the phenomenon called the Arctic Oscillation, according to findings published in the Jan. 5 issue of Nature. (more…)

Read More