Earth | Page 932 | Science Codex

Ice-free Arctic winters could explain amplified warming during Pliocene

Year-round ice-free conditions across the surface of the Arctic Ocean could explain why the Earth was substantially warmer during the Pliocene Epoch than it is today, despite similar concentrations of carbon dioxide in the atmosphere, according to new research carried out at the University of Colorado Boulder.

In early May, instruments at the Mauna Loa Observatory in Hawaii marked a new record: The concentration of carbon dioxide climbed to 400 parts per million for the first time in modern history.

NRL researchers discover novel material for cooling of electronic devices

WASHINGTON-–A team of theoretical physicists at the U.S. Naval Research Laboratory (NRL) and Boston College has identified cubic boron arsenide as a material with an extraordinarily high thermal conductivity and the potential to transfer heat more effectively from electronic devices than diamond, the best-known thermal conductor to date.

NOAA-supported scientists find large Gulf dead zone, but smaller than predicted

NOAA-supported scientists found a large Gulf of Mexico oxygen-free or hypoxic "dead" zone, but not as large as had been predicted. Measuring 5,840 square miles, an area the size of Connecticut, the 2013 Gulf dead zone indicates nutrients from the Mississippi River watershed are continuing to affect the nation's commercial and recreational marine resources in the Gulf.

Global warming endangers South American water supply

Tuesday, July 29: Chile and Argentina may face critical water storage issues due to rain-bearing westerly winds over South America's Patagonian Ice-Field to moving south as a result of global warming.

A reconstruction of past changes in the North and Central Patagonian Ice-field, which plays a vital role in the hydrology of the region, has revealed the ice field had suddenly contracted around 15,000 years ago after a southerly migration of westerly winds.

When fluid dynamics mimic quantum mechanics

CAMBRIDGE, Mass- In the early days of quantum physics, in an attempt to explain the wavelike behavior of quantum particles, the French physicist Louis de Broglie proposed what he called a "pilot wave" theory. According to de Broglie, moving particles — such as electrons, or the photons in a beam of light — are borne along on waves of some type, like driftwood on a tide.

Seemingly competitive co-catalysts cooperate to accelerate chemical reaction

CHESTNUT HILL, MA (July 29, 2013) – A new, computationally-inspired approach has led a team of Boston College chemists to re-conceptualize a highly valued catalytic process, dramatically increasing the efficiency of a chemical transformation that selectively produces chiral, or handed, molecules valued for medical and life sciences research, the team reports in the current online edition of the journal Nature Chemistry.

Experimental quest to test Einstein's speed limit

Albert Einstein's assertion that there's an ultimate speed limit – the speed of light – has withstood countless tests over the past 100 years, but that didn't stop University of California, Berkeley, postdoc Michael Hohensee and graduate student Nathan Leefer from checking whether some particles break this law.

How well do fossil assemblages of the Ediacara Biota tell time?

Fossils of the Precambrian Ediacara Biota hold the key to understanding the origin and evolution of early animal life on this planet. Abundant fossils of these soft-bodied organisms occur globally and span 40 million years.

These fossils have traditionally been loosely grouped into three associations interpreted to have temporal significance -- with certain fossils representing older rocks and others representative of younger times.

Erosion-induced isostatic rebound triggers extension in low convergent mountain ranges

Earthquakes occur even in places where no deformation related to horizontal tectonic plate motion is expected.

Among the regions where no present-day horizontal deformation can be quantified to the level of accuracy of GPS measurements (i.e., 0.3 mm/yr), the Alps and the Pyrenees mountain ranges (Western Europe) or the New Madrid area (USA) can be cited.

'Event attribution' says East African drought made more likely by climate change

In 2011 a powerful drought gripped East Africa. The failure of both the 2010 fall rains and the 2011 spring rains caused a drought that, stacked on an already unstable political climate, caused a famine that led to hundreds of thousands of deaths.

Whenever an extreme weather event strikes a population—a drought, a hurricane, or a powerful flood—questions arise as to whether ongoing global climate change is complicit.

New knowledge about permafrost improving climate models

New research findings from the Centre for Permafrost (CENPERM) at the Department of Geosciences and Natural Resource Management, University of Copenhagen, document that permafrost during thawing may result in a substantial release of carbon dioxide into the atmosphere and that the future water content in the soil is crucial to predict the effect of permafrost thawing. The findings may lead to more accurate climate models in the future.

Stability of the nitrogen cycle in the redox-stratified late Paleoproterozoic Ocean

Around 1,840 million years ago, a widespread transition to euxinia occurred along productive continental margins.

Seismic studies provide new detail on transition zone below western US

At certain depths in Earth's mantle, the increasing pressure causes minerals to undergo phase changes, transforming to different crystal structures. Seismic waves change speed at these discontinuities, so analyzing seismic waves gives scientists information about the structure of the mantle.

Stratigraphic, geochronologic, and geochemical record of the Cryogenian Perry Canyon Formation

The Cryogenian Period (800-635 million years ago) represents a time of profound and interrelated global tectonic, climatic, and biologic changes, involving the breakup of the supercontinent Rodinia, extreme glaciations, and a drastic turnover in the diversity and morphology of life on Earth.

The solid Earth's influence on sea level

Sea level lies at the intersection of Earth's solid, liquid, and gaseous components, and thus forms a fundamental boundary on our planet that affects both biology and geology.

Human society must adjust to changes in this boundary, which is now rising 2-3 mm per year. Although climatological factors such as seawater warming and glacial melting are major contributors to sea level rise, deformation of the solid earth also exerts an important, and often dominating, influence on sea level.