Scientists at the Naval Research Laboratory - Stennis Space Center (NRL-SSC) have directly derived the air-sea momentum exchange at the ocean interface using observed ocean currents under Hurricane Ivan and determined that it decreases when winds exceed 32 meters per second. This is the first time that momentum exchange at the air-sea interface has been directly calculated from ocean current observations under extreme winds generated by a major tropical cyclone.
A new climate modeling study forecasts the complete disappearance of several existing climates in tropical highlands and regions near the poles, while large swaths of the tropics and subtropics may develop new climates unlike any seen today.
In general, the models show that existing climate zones will shift toward higher latitudes and higher elevations, squeezing out the climates at the extremes--tropical mountaintops and the poles--and leaving room for unfamiliar climes and new ecological niches around the equator.
The Himalaya, the “Roof of the World”, source of the seven largest rivers of Asia are, like other mountain chains, suffering the effects of global warming. To assess the extent of melting of its 33 000 km2 of glaciers, scientists have been using a process they have been pioneering for some years. Satellite-imagery derived glacier surface topographies obtained at intervals of a few years were adjusted and compared. Calculations indicated that 915 km2 of Himalayan glaciers of the test region, Spiti/Lahaul (Himachal Pradesh, India) thinned by an annual average of 0.85 m between 1999 and 2004.
Scientists of the University of Almeria, led by Gabriel Acién, are carrying out a research project on the development of new systems to eliminate carbon dioxide emissions thanks to the microalgae photosynthetic activity. This project, called CENIT CO2, is being developed by Spanish electricity company Endesa on the initiative of the Spanish Ministry of Industry.
Scientists from the NIOZ Royal Netherlands Institute for Sea Research obtained for the first time a detailed temperature record for tropical central Africa over the past 25,000 years. They did this in cooperation with a German colleague from the University of Bremen, The scientists developed an entirely new method to reconstruct the history of land temperatures based on the molecular fossils of soil bacteria. They applied the method to a marine sediment core taken in the outflow of the Congo River. This core contained eroded land material and microfossils from marine algae.
The theory that Earth once underwent a prolonged time of extreme global freezing has been dealt a blow by new evidence that periods of warmth occurred during this so-called 'Snowball Earth' era.
Analyses of glacial sedimentary rocks in Oman, published online today in Geology, have produced clear evidence of hot-cold cycles in the Cryogenian period, roughly 850-544 million years ago. The UK-Swiss team claims that this evidence undermines hypotheses of an ice age so severe that Earth's oceans completely froze over.
A new study out of Alaska points out the impacts of climate change on marine ecosystems, and the need for increased research and stronger science based management to address future concerns.
Studies by a team of scientists at the North Pacific Universities Marine Mammal Research Consortium http://www.marinemammal.org/ revealed that a sudden ocean climate change 30 years ago changed today’s Alaska marine ecosystems, and may be a leading factor in the decline of Alaska’s endangered western stock of Steller sea lions.
Identification of the oldest preserved pieces of Earth's crust in southern Greenland has provided evidence of active plate tectonics as early as 3.8 billion years ago, according to a report by an international team of geoscientists in the March 23 edition of Science magazine.
The success of science based management in Alaska is emphasized in a newly released report. “Conserving Alaska’s Oceans,” was prepared by Natural Resources Consultants, a research organization based in Seattle, Washington and released by the Marine Conservation Alliance. The report outlines 30 years of improved ocean conservation in the waters off Alaska with recommendations for future action. The “Alaska Model” has been cited as a leading example of science-based management.
Scientists from NOAA’s Earth System Research Laboratory (ESRL) announced today a new tool to monitor changes in atmospheric carbon dioxide and other greenhouse gases by region and source. The tool, called CarbonTracker, will enable its users to evaluate the effectiveness of their efforts to reduce or store carbon emissions.
The entire debate about global warming is a mirage. The concept of ‘global temperature’ is thermodynamically as well as mathematically an impossibility, says professor at The Niels Bohr Institute, University of Copenhagen, Bjarne Andresen who has analyzed this hot topic in collaboration with professors Christopher Essex from University of Western Ontario and Ross McKitrick from University of Guelph, both Ontario, Canada.
Scientists have identified four Antarctic glaciers that pose a threat to future sea levels using satellite observations, according to a study published in the journal Science.
Experts from the University of Edinburgh and University College London determined the effect that Antarctica and Greenland were having on global sea level in a comprehensive evaluation of the Earth’s ice sheets. They found that together these two ice-sheets were responsible for a sea level rise of 0.35 millimetres per year over the past decade – representing about 12 per cent of the current global trend.
It has long been recognized that birds possess the ability to use the Earth’s magnetic field for their navigation, although just how this is done has not yet been clarified. However, the discovery of iron-containing structures in the beaks of homing pigeons in a new study (1) by Gerta Fleissner and her colleagues at the University of Frankfurt offers a promising insight into this complex topic. The article will be published online mid-March in Springer’s journal Naturwissenschaften.
More than three-quarters of the particulate pollution known as black carbon transported at high altitudes over the West Coast during spring is from Asian sources, according to a research team led by Professor V. Ramanathan at Scripps Institution of Oceanography, UC San Diego.
Though the transported black carbon, most of which is soot, is an extremely small component of air pollution at land surface levels, the phenomenon has a significant heating effect on the atmosphere at altitudes above two kilometers (6,562 feet).
Plants can do it: they simply grab carbon dioxide out of the air and covert it into biomass. In this process, known as photosynthesis, the plants use light as their energy source. Chemists would also like to be able to use CO2 as a carbon source for their synthetic reactions, but it doesn’t work just like that. A team headed by Markus Antonietti at the Max Planck Institute for Colloids and Interfaces has now taken an important step toward this goal.