Earth | Page 1355 | Science Codex

Silent streams? Escalating endangerment for North American freshwater fish

Nearly 40 percent of fish species in North American streams, rivers and lakes are now in jeopardy, according to the most detailed evaluation of the conservation status of freshwater fishes in the last 20 years.

The 700 fishes now listed represent a staggering 92 percent increase over the 364 listed as "imperiled" in the previous 1989 study published by the American Fisheries Society. Researchers classified each of the 700 fishes listed as either vulnerable (230), threatened (190), or endangered (280). In addition, 61 fishes are presumed extinct.

Engineers develop a laser solution to power plants slowed by slagging

Quietly, and with little of the fanfare accompanying the relentless surge in gasoline costs, the price of coal has doubled in less than a year.

The reasons are varied. Worldwide demand for coal is growing sharply. Bad weather has hampered production in Australia and China. Shipping problems have slowed exports from Australia and South Africa.

Because coal-fired power plants produce half the electricity in the U.S., the spike in prices has increased utility bills in some states, just as consumers are already coping with rising food and gas prices.

Moderate quantities of dirt make more rain

Drought or deluge - scientists working with Meinrat O. Andreae, Director at the Max Planck Institute for Chemistry in Mainz, have now discovered how aerosols affect the when, where and how much of rainfall. Until now, the answers to these questions have been as varied as they have been inconsistent. Andreae and his co-authors are now tracing a common theme through the sometimes contradictory effects that these tiny particles have on precipitation.

Fuel emissions from marine vessels remain a global concern

The forecast for clear skies and smooth sailing for oceanic vessels has been impeded by worldwide concerns of their significant contributions to air pollution and greenhouse gas emissions that impact the Earth's climate.

A new study by professors James Winebrake and James Corbett examines "Emission Tradeoffs among Alternative Marine Fuels: Total Fuel Cycle Analysis of Residual Oil, Marine Gas Oil, and Marine Diesel Oil," in a recent issue of Journal of the Air & Waste Management Association.

Climate: New spin on ocean's role

New studies of the Southern Ocean are revealing previously unknown features of giant spinning eddies that have a profound influence on marine life and on the world's climate.

These massive swirling structures – the largest are known as gyres - can be thousands of kilometres across and can extend down as deep as 500 metres or more, a research team led by a UNSW mathematician, Dr Gary Froyland, has shown in the latest study published in Physical Review Letters.

Compost heap bacteria could provide 10 percent of UK transport fuel needs

Bacteria found in compost heaps able to convert waste plant fibre into ethanol could eventually provide up 10% of the UK's transport fuel needs, scientists heard today (Tuesday 9 September 2008) at the Society for General Microbiology's Autumn meeting being held this week at Trinity College, Dublin.

Scientists point to forests for carbon storage solutions

COLUMBUS, Ohio – Scientists who have determined how much carbon is stored annually in upper Midwest forests hope their findings will be used to accelerate global discussion about the strategy of managing forests to offset greenhouse gas emissions.

Climate computer modeling heats up

New "petascale" computer models depicting detailed climate dynamics, and building the foundation for the next generation of complex climate models, are in the offing.

Researchers at the University of Miami Rosenstiel School of Marine and Atmospheric Science (RSMAS), the National Center for Atmospheric Research (NCAR) in Boulder, Colo., the Center for Ocean-Land-Atmospheric Studies (COLA) in Calverton, Md., and the University of California at Berkeley are using a $1.4 million award from the National Science Foundation (NSF) to generate the new models.

Valley networks on Mars formed during long period of episodic flooding

SANTA CRUZ, CA--A new study suggests that ancient features on the surface of Mars called valley networks were carved by recurrent floods during a long period when the martian climate may have been much like that of some arid or semiarid regions on Earth. An alternative theory that the valleys were carved by catastrophic flooding over a relatively short time is not supported by the new results.

US Air Force technology helps scientists understand plant root function

MADISON, WI SEPTEMBER 8, 2008-- The McClellan Nuclear Radiation Center (MNRC) in Sacramento, CA was developed by the U.S. Air Force to detect corrosion and defects in aircraft structure using an imaging technique called neutron radiography. This technique is currently helping soil scientists understand the function of plant roots and their uptake of water and nutrients.

Global sea-rise levels by 2100 may be lower than some predict, says CU-Boulder study

Despite projections by some scientists of global seas rising by 20 feet or more by the end of this century as a result of warming, a new University of Colorado at Boulder study concludes that global sea rise of much more than 6 feet is a near physical impossibility.

Researcher says: No-till practices show extended benefits on wheat and forage

VERNON – With more than 3 million acres of wheat in north Texas, 50 percent or more of which is grazed by 1 to 2 million head of cattle, it is important to look at tillage practices and their effect on forage production, said a Texas AgriLife Research expert.

Theory of the sun's role in formation of the solar system questioned

A strange mix of oxygen found in a stony meteorite that exploded over Pueblito de Allende, Mexico nearly 40 years ago has puzzled scientists ever since. Small flecks of minerals lodged in the stone and thought to date from the beginning of the solar system have a pattern of oxygen types, or isotopes, that differs from those found in all known planetary rocks, including those from Earth, its Moon and meteorites from Mars.

Global sea-rise levels by 2100 my be lower than some predict, says CU-Boulder study

Despite projections by some scientists of global seas rising by 20 feet or more by the end of this century as a result of warming, a new University of Colorado at Boulder study concludes that global sea rise of much more than 6 feet is a near physical impossibility.

Smoke smudges Mexico City's air, chemists identify sources

Mexico City once topped lists of places with the worst air pollution in the world. Although efforts to curb emissions have improved the situation, tiny particles called aerosols still clog the air. Now, atmospheric scientists from UC San Diego and six other institutions have sorted through the pall that hangs over the city to precisely identify aerosols that make up the haze and chart daily patterns of changes to the mix.