Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Politics : The Exxon Free Environmental Thread -- Ignore unavailable to you. Want to Upgrade?

To: Wharf Rat who wrote (831)	6/26/2007 7:57:53 AM
From: Ron	Read Replies (1) \| Respond to of 48970

Climate Changes Are Making Poison Ivy More Potent June 26, 2007 Poison ivy, the scourge of summer campers, hikers and gardeners, is getting worse. New research shows the rash-inducing plant appears to be growing faster and producing more potent oil compared with earlier decades. The reason? Rising ambient carbon-dioxide levels create ideal conditions for the plant, producing bigger leaves, faster growth, hardier plants and oil that's even more irritating. Although the data on poison ivy come from controlled studies, they suggest the vexing plant is more ubiquitous than ever. And the more-potent oil produced by the plants may result in itchier rashes. "If it's producing a more virulent form of the oil, then even a small or more casual contact will result in a rash," says Lewis Ziska, a plant physiologist for the U.S. Department of Agriculture in Beltsville, Md. The latest research, led by Dr. Ziska, studied poison ivy plants in Maryland under different levels of carbon-dioxide exposure. One group of plants was exposed to about 300 parts per million of carbon dioxide -- about the same level found in the atmosphere in the 1950s. Another group was exposed to 400 parts per million of CO2 -- about the same level in the atmosphere today. After about eight months, leaf size, stem length and weight and oil content of the plants raised at current carbon-dioxide levels were, on average, 50% to 75% higher than the plants under the 1950s conditions, according to the study, expected to be published this year in the journal Weed Science. Not only did the higher CO2 level double the growth rate, but it made for hardier plants that recovered more quickly from the ravages of grazing animals. The latest research follows a Duke University report last year that higher carbon-dioxide levels create a chemical change in poison ivy that results in a more potent form of urushiol, the oil that triggers an itchy rash in about 70% of people exposed to it. "It is more abundant and allergenic," says Jacqueline E. Mohan, who led the Duke study and is now assistant professor at the University of Georgia in Athens. [Go to the slideshow]4 www.poison-ivy.org Poison ivy can be both shiny and dull -- even on the same stalk. Poison ivy is difficult to identify. Hikers have long known the adage "leaves of three, let them be." But poison ivy, usually found east of the Rocky Mountains, can sometimes have more leaves and look like a shrub or vine. The leaves can range from one to six inches, and be notched or smooth. Depending on the season, they can be red or green. One Web site, www.poison-ivy.org5, offers cards with life-size images to help identify the plant in its various incarnations. Long pants, long-sleeve shirts and socks can help, but clothes need to be removed and washed to avoid contact with urushiol that may have brushed on clothing. The oil can penetrate rubber gloves and boots, so vinyl gloves are recommended if you're trying to remove the plants. One treatment, sold as IvyBlock, is rubbed on exposed areas before contact to prevent a rash. A 1995 study found the treatment prevented or significantly reduced poison ivy reactions. Despite protective clothes and washing, Yale nursing professor Patricia Jackson Allen still contracted a rash on her forearms after gardening this weekend. The precautions prevented a more severe rash, but "I haven't found anything that works 100% for me,'' she says. If you think you've come into contact with poison ivy, wash immediately. But if more than 10 minutes has passed, soap and water removes only about half the oil. A 2000 study found that Tecnu, an over-the-counter poison ivy wash, is about 70% effective in eliminating urushiol two to eight hours after exposure. Goop, a grease remover and Dial Ultra dishwashing soap were about 60% effective, according to a 2004 article in Pediatric Nursing. Rubbing alcohol also helps. If exposure does occur, over-the-counter topical lotions may provide some relief. Severe cases can be treated with steroids by a doctor. • Email: healthjournal@wsj.com6 URL for this article: online.wsj.com

To: Wharf Rat who wrote (831)	6/26/2007 11:36:50 AM
From: Wharf Rat	Respond to of 48970

Desert dust cuts mountain snow, may spur warming By Deborah Zabarenko, Environment Correspondent Mon Jun 25, 4:09 PM ET WASHINGTON (Reuters) - Desert dust blown onto Rocky Mountain peaks has cut the duration of snow-cover by a month or more, and the same thing is probably happening in the Alps and Himalayas, researchers reported on Monday. In a phenomenon likely to spur global warming, the reflective white of snow is replaced by darker dust deposits that absorb the sun's rays, heating up the lower atmosphere, said Tom Painter, a scientist at the National Snow and Ice Data Center in Colorado. Speaking by telephone from Mont Blanc in Switzerland, Painter described an orange tinge he had seen on the snow of nearby Dome de Miage, which he attributed to dust carried from the Sahara in Africa. Painter said he had observed dust-laden snow on the Tien Shan Mountains in China, and the same likely held true for parts of the Himalayas. "I don't know of any mountain ranges that are not experiencing dust deposition," Painter said. Dust in small doses can help to form snowflakes, but the dust that cuts the length of snow-pack in the Rockies by about 20 to 35 days a year comes in a swirling blanket, spawned by wind storms in desert or drought-stricken areas, Painter and his co-authors wrote online in Geophysical Research Letters. The fact that dust deposits can melt mountain snow by decreasing the ability to reflect sunlight has long been established; what is new, Painter said, is the degree to which this affects snow cover. One month less of snow "is an enormous change," he said. The desert dust-mountain snow system warms up the lower atmosphere in what climate scientists call a positive feedback loop, Painter explained: "The hotter it gets, the less snow cover you have ... and that provides a darker surface that can absorb more solar radiation and that warms things even more." The cause for the diminished snow cover in Colorado's San Juan Mountains is dust carried from the Colorado Plateau, some 200 miles away, where Colorado, Utah, Arizona and New Mexico come together in an area known as Four Corners, the researchers said. The underlying reason for the increased dust is changes in land use starting in the mid-19th century, Painter said. "About 75 percent of the Western United States has been affected by grazing, by agriculture, by mining," he said. "Generally these lands were pretty stable prior to the large-scale introduction of grazing and agriculture." Without natural grasses to stabilize the soil, more of it turned to desert and more dust blew into the mountains. Most climate models predict more drying and warming in the U.S. desert Southwest, causing soil moisture to decrease, which means less vegetation to stabilize the soil and probably more dust emission, Painter said. This, in turn, could mean even more intense snow melt, earlier in the year, spurring the whole cycle, he said. news.yahoo.com