Enn Original News
February 8, 2011 04:10 PM - Andy Soos, ENN
Thundersnow, also known as a winter thunderstorm or a thunder snowstorm, is a relatively rare kind of thunderstorm with snow falling as the primary precipitation instead of rain. It typically falls in regions of strong upward motion within the cold sector of an extratropical cyclone, where the precipitation consists of ice pellets rather than snow. Snowstorms that trigger lightning are rare. Of the roughly 10,000,000 cloud-to-ground lightning flashes observed over the continental United States each year, about 0.1 percent to 0.01 percent are associated with snow, says Walter Petersen, atmospheric physicist with NASA's Marshall Space Flight Center in Huntsville, Alabama. This thundersnow happened this winter in northern Alabama and was observed first hand by sophisticated lightning mapping station in Huntsville
The Dunes of Mars
February 7, 2011 12:41 PM - Andy Soos, ENN
A dune is a hill of sand built by the wind. Dunes occur in different forms and sizes. Most kinds of dunes are longer on the windward side where the sand is pushed up the dune and have a shorter slip face in the lee of the wind. Dunes can be found in any environment where there is a substantial atmosphere, winds, and dust to be blown. Dunes are common on Mars, and they have also been observed in the equatorial regions of Titan. Sand dunes in a vast area of northern Mars long thought to be frozen in time are changing with both sudden and gradual motions, according to research using images from a NASA orbiter. These dune fields cover an area the size of Texas in a band around the planet at the edge of Mars' north polar cap. The new findings suggest they are among the most active landscapes on Mars. However, few changes in these dark-toned dunes had been previously detected before a campaign of repeated imaging by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.
February 4, 2011 12:29 PM - Andy Soos, ENN
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. A new, wide-ranging survey that compares the past and present condition of oyster reefs around the world finds that more than 90 percent of former reefs have been lost in most of the bays and ecoregions where the prized molluscs were formerly abundant. In many places, such as the Wadden Sea in Europe and Narragansett Bay, oysters are rated "functionally extinct," with fewer than 1 percent of their former reefs persisting. The declines are in most cases a result of over harvesting of wild populations and disease, often exacerbated by the introduction of non-native species. Oysters have fueled coastal economies for centuries, and were once astoundingly abundant in favored areas.
The Alarming Amazon Droughts of 2005 and 2010
February 4, 2011 08:58 AM - David A Gabel, ENN
When thinking of the wettest place on land, most people think about rainforests such as the Amazon, which can get up to 78 inches of rain per year. All this precipitation supports the Amazon's rich plant life which helps moderate carbon dioxide levels in the atmosphere. It is then quite alarming to learn that the Amazon has suffered two devastating droughts in the last five years. Researchers fear a continuation of this disturbing trend.
New from BBC Earth: America's National Parks
February 4, 2011 08:54 AM - BBC Earth
Once hailed as 'America’s best idea', Yellowstone was the world's first national park. Changing the way we interact with nature, the Pulitzer prize-winning author Wallace Stegner put it best when he said national parks "reflect us at our best, not our worst". In the gigantic 3.5million square miles of land, Yellowstone is host to a large number of interesting animal species, including bison, cougars, lynx, bobcats and coyotes. The whole park actually sits on a caldera, often referred to as a 'supervolcano', and has at its heart the same conditions that brought about the start of life on Earth. This means it holds one of the world’s natural wonders. The volcano means Yellowstone remains geologically very active. Recent changes in the volcanic springs have killed these pines by cooking their roots, as the branches freeze in winter. It's safe to say that Yellowstone is a place of natural beauty that's inspired conservation and preserved countless areas of outstanding natural interest around the world.
Gowanus Canal Superfund Site
February 3, 2011 03:55 PM - Andy Soos, ENN
The U.S. Environmental Protection Agency has completed its investigation of the Gowanus Canal Superfund site in Brooklyn, N.Y. The investigation confirmed the widespread presence of numerous contaminants in the canal and identified the sources of contamination. The investigation also identified characteristics of the canal that will influence future plans for a cleanup. A companion human and ecological risk assessment found that exposure to the contaminants in the canal poses potential threats to people’s health and the environment. The Gowanus Canal was originally built to allow access for industrial needs by bulkheading and dredging a tidal creek and wetland that had previously been fished for oysters. After its completion in the 1860s, the canal quickly became one of the nation’s busiest industrial waterways, home to heavy industry including gas works, coal yards, cement makers, soap makers, tanneries, paint and ink factories, machine shops, chemical plants, and oil refineries. It was also the repository of untreated industrial wastes, raw sewage, and surface water runoff for decades, causing it to become one of New York’s most polluted waterways. Although much of the industrial activity along the canal has stopped, high contaminant levels remain in the sediments.
Brazil Approves Construction of the Belo Monte Dam Project
February 2, 2011 11:07 AM - David A Gabel, ENN
The proposed Belo Monte Dam in northern Brazil would be the third largest hydro-electric dam in the world in terms of electrical output. The dam would be 3.75 miles long and generate over 11,000 megawatts, which could power up to 23 million homes. Government officials say that the dam is an essential step in supplying energy to the nation's growing population. However, the project is rife with environmental conflicts. The project requires the clearing of 588 acres of Amazon jungle, the displacement of over 20,000 indigenous people, flooding a 193 square mile area, and drying up a 62 mile stretch of the Xingu River.
Eurasian Arctic Rivers
February 2, 2011 08:55 AM - Andy Soos, ENN
Changes in the amount and timing of the discharge of major Eurasian Arctic rivers have been well documented, but whether or not these changes can be attributed to climatic factors or to the construction of man made reservoirs remains unclear. A new research report helps to identify the key processes (snow cover and air temperature) that have regulated seasonal stream flow fluctuations in the Eurasian Arctic over the last half-century (1958—1999) and to understand the regional coherence of timing trends, using a set of Eurasian Arctic rivers selected specifically because they are free of known effects of dams. A shift toward the earlier onset of spring runoff as measured by a modest change in the spring pulse onset (26 of 45 stations) and a strong change in the timing (39 of 45 stations). Winter stream flows increased over the period of record in most rivers, suggesting that trends observed by others in larger regulated Eurasian Arctic rivers may not be entirely attributable to reservoir construction.
Australian Cyclone Yasi
February 1, 2011 04:27 PM - Andy Soos, ENN
Down under they are called cyclones. In the Atlantic they are called hurricanes. Queensland in northeast Australia has recently been hit with devastating floods. Now Yasi, a very large cyclone, is bearing down. Yasi has reached maximum sustained winds near 90 knots (103 mph), equivalent to a Category Two hurricane on the Saffir-Simpson Scale early on January 31). Since then the winds have increased to a category 3 storm. It was centered about 875 miles east of Cairns, Australia, moving west at about 19 knots per hour (22 mph). Cyclone-force winds extend out to 30 miles from the center. Yasi is forecast to move west, then southwestward, into an area of low vertical wind shear (strong wind shear can weaken a storm). Forecasters at the Joint Typhoon Warning Center expect Yasi to continue to strengthen over the next 36 hours. The Center forecasts a landfall just south of Cairns as a large 100-plus knot-per-hour (115 mph) system by around midnight local time on February 2.
Humans Share Genetic Ancestry with Orangutans
February 1, 2011 12:17 PM - David A Gabel, ENN
For those who believe in the theory of evolution, the general consensus is that mankind evolved from chimpanzees. Chimps are man's most closely related living species. While that may be true, a new study published in the online journal, Genome Research, has a surprising new finding. Parts of the human genome are more closely related to the orangutan.