Solar Storms Affirmative – 4 Week Lab [1/3]
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- Warming can cause irreversible damage to the critical coral reefs Union of Concerned Scientists
- Coral’s key to global biodiversity—offers unique geological and biological structures to sustain life
- Reefs key to biodiversity, hunger, industry, and lifesaving medicines
Impact – ReefsWarming kills reefs which are key to biodiversity Alok Jha, science correspondent for The Guardian, 1-24-08, Hurricanes and global warming devastate Caribbean coral reefs, http://www.guardian.co.uk/environment/2008/jan/24/climatechange Warmer seas and a record hurricane season in 2005 have devastated more than half of the coral reefs in the Caribbean, according to scientists. In a report published yesterday, the World Conservation Union (IUCN) warned that this severe damage to reefs would probably become a regular event given current predictions of rising global temperatures due to climate change. According to the report, 2005 was the hottest year on average since records began and had the most hurricanes ever recorded in a season. Large hotspots in the Atlantic and the Gulf of Mexico powered strong tropical hurricanes such as Katrina, which developed into the most devastating storm ever to hit the US. In addition to the well-documented human cost, the storms damaged coral by increasing the physical strength of waves and covering the coast in muddy run-off water from the land. The higher sea temperature also caused bleaching, in which the coral lose the symbiotic algae they need to survive. The reefs then lose their colour and become more susceptible to death from starvation or disease. Impacts Carl Gustaf Lundin, head of the IUCN's global marine programme, said: "Sadly for coral reefs, it's highly likely extreme warming will happen again. When it does, the impacts will be even more severe. If we don't do something about climate change, the reefs won't be with us for much longer." Some of the worst-hit regions of the Caribbean, which contains more than 10% of the world's coral reefs, included the area from Florida through to the French West Indies and the Cayman Islands. In August 2005 severe bleaching affected between 50% and 95% of coral colonies and killed more than half, mostly in the Lesser Antilles. The IUCN report highlights pressures on coral reefs in addition to those of overfishing and pollution identified in recent years. A recent study found that reefs near large human populations suffered the most damage. Coral reefs are an important part of the marine ecosystem, supporting an estimated 25% of all marine life including more than 4,000 species of fish. They provide spawning, nursery, refuge and feeding areas for a wide variety of other creatures such as lobsters, crabs, starfish and sea turtles. Reefs also play a crucial role as natural breakwaters, protecting coastlines from storms. "It's quite clear that the structure and their function as they are right now in the Caribbean is quite severely impeded," said Lundin. "Over the next few decades we will see a large reduction in the number of reef areas." Reefs also boost the local economy - in the Caribbean coral reefs provide more than $4bn (£2bn) a year from fisheries, scuba-diving tourism and shoreline protection. According to an analysis by the World Resources Institute: Reefs at Risk, coral loss in the region could cost the local economy up to $420m every year. Warming can cause irreversible damage to the critical coral reefs Union of Concerned Scientists, 8-10-05, “Early Warning Signs: Coral Reef Bleaching” Coral reefs are one of the most productive ecosystems on Earth, providing many critical services to fisheries, shoreline protection, tourism, and to medicine. They are also believed to be among the most sensitive ecosystems to long-term climate change (Nurse et al., 1998). Elevated sea surface temperatures can cause coral to lose their symbiotic algae, which are essential for the nutrition and color of corals. When the algae die, corals appear white and are referred to as "bleached." Water temperatures of as little as one degree Celsius above normal summer maxima, lasting for at least two to three days, can be used as a predictor of coral bleaching events (Goreau and Hayes, 1994). Studies indicate that most coral are likely to recover from bleaching if the temperature anomalies persist for less than a month, but the stress from sustained high temperatures can cause physiological damage that may be irreversible (Wilkinson et al., 1999). Coral’s key to global biodiversity—offers unique geological and biological structures to sustain life Robert W. Buddemeier, KANSAS GEOLOGICAL SURVEY, Joan A. Kleypas, NATIONAL CENTER FOR ATMOSPHERIC RESEARCH, and Richard B. Aronson, DAUPHIN ISLAND SEALAB, February 2004 “Coral reefs Potential Contributions of Climate Change to Stresses on Coral Reef Ecosystems & Global climate change” Published by the Pew Center for Climate Change Coral reefs offer many values to human society and to the health of the biosphere. Reefs support fisheries, and reef structures provide natural breakwaters that protect shorelines, other ecosystems, and human settlements from waves and storms. Humans use reefs and reef products extensively for food, building materials, pharmaceuticals, the aquarium trade, and other products. Due to their grandeur, beauty, and novelty, reefs have become prime tourist destinations and, therefore, economic resources. Less evident are the multiple “ecosystem services” of coral reefs, such as recycling nutrients and providing food, shelter, and nursery habitat for many other species. Many of these services are related to the geologic and biologic structures that create the spatial complexity necessary for the high biodiversity of reefs. The biodiversity is not all marine; humans, like many seabirds and other air-breathing species, have colonized island and coastal environments formed by coral reef communities. Reefs key to biodiversity, hunger, industry, and lifesaving medicines Charles W. Schmidt, science writer specializing in the environment, genomics, and information technology, Jul 08 “In Hot Water: Global Warming Takes a Toll on Coral Reefs” http://www.ehponline.org/members/2008/116-7/focus.html In the summer of 2005, while Atlantic hurricanes battered coastlines from Cuba to Mexico, the Eastern Caribbean baked under a relentless sun with barely a breeze to cool the air. Tourists and locals alike wilted in the heat, and below the sea, marine life and corals in particular suffered as well. The windless calm settled in just as a buildup of unusually warm water began accumulating in the region. Ordinarily, easterly trade winds would have churned the sea, helping it to cool. But thanks to an unprecedented heat wave beginning in May—the result of a confluence of factors related to climate change, scientists say—water temperatures in the Eastern Caribbean climbed and stayed high for months, reaching levels that by September would be warmer than any recorded in 150 years. The heat disturbed a symbiotic partnership that coral animals normally maintain with a type of algae called zooxanthellae. Zooxanthellae supply corals with essential nutrients produced by photosynthesis, particularly carbon, in return for the shelter and access to sunlight provided by the reefs. The algae also impart color to the corals, which themselves are colorless. But as sea temperatures rose, the zooxanthellae disappeared, leaving their carbon-deprived hosts behind to starve. The reefs turned snow white, the color of the underlying stonelike structures they had built up over centuries, in a phenomenon known as coral bleaching. As the heat wave progressed, it left a trail of bleached reefs the likes of which had never been seen in the Caribbean. By year's end, coral cover ranging from 90% in the Virgin Islands to 52% in the French West Indies was affected. Coral bleaching isn't always fatal—if water temperatures cool in time, the zooxanthellae might return, allowing corals to recover. But in parts of the Eastern Caribbean, the reefs never got a chance. Almost as soon as their recovery started, they were attacked by diseases affecting a range of coral species down to 60 feet. By 2007, roughly 60% of the coral cover in the Virgin Islands and 53% in Puerto Rico's La Parguera Natural Reserve was dead—an unprecedented tragedy. The Eastern Caribbean disease outbreak came on the heels of what's been a rough several decades for coral reefs worldwide. Long suffering from land-based pollution, habitat destruction, and overfishing, coral reefs now must also contend with climate change, which has accelerated their global decline. This puts a wealth of biodiversity at risk. Reefs support up to 800 types of coral, 4,000 fish species, and countless invertebrates. Reef-dwelling species numbering in the hundreds of thousands may not even be catalogued yet, some scientists speculate. The implications of these declines could be as disastrous for human health as they are for marine life. Globally, reefs provide a quarter of the annual fish catch and food for about 1 billion people, according to the United Nations Environment Programme. Reefs protect shorelines from storm surges, which could become more powerful as sea levels rise with climate change. Tourism—a mainstay of coastal economies in the tropics, worth billions in annual revenue—could suffer if reefs lose their appeal. Reefs are also a long-standing source of medicines to treat human disease. Being attached to reefs, corals and other immobilized marine animals can't escape predators, so they deploy a range of chemical compounds to deter hunters, fight disease, and thwart competing organisms. Two antiviral drugs (vidarabine and azidothymidine) and the anticancer agent cytarabine were developed using compounds extracted from Caribbean reef sponges. Another product called dolastatin 10, isolated from the sea hare (Dolabella auricularia) of the Indian Ocean, has been investigated as a treatment for breast and liver cancers and leukemia. Many more lifesaving medicines and useful chemical products could one day be derived from reef dwellers, experts say. Saving these ecosystems is imperative on a range of levels, says Caroline Rogers, a marine ecologist with the U.S. Geological Survey in St. John, U.S. Virgin Islands. "We have to save them for economic, ecological, aesthetic, and even spiritual reasons," she says. "People need to feel connected with nature and with systems that are bigger than they are. Coral reefs are awe-inspiring—we're losing something that we barely understand." Directory: file -> view view -> Western Europe after wwii view -> Author study: paul fleischman view -> Qpa1 7ela study Guide view -> Arctic Oil/Gas Neg view -> November 1970 Approximately 150,000-500,000 deaths Bhola Cyclone Bangladesh view -> Grade Level: 6 Unit of Study: Caribbean glce view -> Citation: Duffield, Katy view -> Table of Contents Lesson # view -> Chinese Wind Energy Disad Download 0.93 Mb. Share with your friends:
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