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Debate
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Harm answers ============ Spills decreasing now --------------------- OIL EXPLORATION DECREASES NATURAL OIL SPILLS, AND HUMAN INDUCED SPILLS ARE DECREASING Bjorn Lomborg, Associate Professor of Statistics in the Political Science Dept of University of Aarhus, Denmark, 2001, THE SKEPTICAL ENVIRONMENTALIST: MEASURING THE REAL STATE OF THE WORLD, p. 189-190 (BLUEOC 0856) Natural oil spills originate from cracks in the bottom of the sea above oil reserves. It may come as a surprise, but mankind's exploitation of oil has relieved the pressure on many of these oil pockets and presumably reduced the natural leak of oi1. However, neither of these two sources of oil pollution has been particularly well documented over time. We are well aware on the other hand, from international statistics, what has happened over time when it comes to accidental oil spills. Figure 102 shows both the number of major tanker accidents and the overall quantity of oil spilt. Well over 80 percent of the spilt oil originates from major accidents. It is quite clear that the number of accidental spills has been reduced over time: whereas there were about 24 major accidents a year before 1980 there were about nine a year in the 1980s and just eight in the 1990s. Similarly, the quantity of oil spilt fell from about 318,000 tons a year in the 1970s to just 110,000 tons in the 1990s. US OIL SPILLS ARE AT A HISTORIC LOW David Krapf, Staff Writer, February 1st 2003, WORKBOAT MAGAZINE, P.4 (BLUEOC 0864) The November sinking of the single-hull tanker Prestige and subsequent oil spill has raised a few questions, the most important being what are the chances of a major oil spill occurring in U.S. waters? In light of the Prestige spill off the Spanish coast, the U.S. Senate held a hearing recently on the phase-out of single-hull tank vessels. Most of the news was good. In the 10 years after the passage of the Oil Pollution Act of 1990, there was a 70 percent reduction in oil spills in the U.S., where these mishaps are now at a historic low OIL SPILLS IN THE US ARE AT AN ALL TIME LOW- OIL LEAKAGE IS MINIMAL PETROLEUM ECONOMIST March 18th 2003 p. 21 (BLUEOC 0865) It was clear from the committee hearing and the evidence given that since the introduction of OPA 90, oil spills in the US have been drastically reduced. There have been no major environmental incidents involving tankers in the US since 1990, spills have fallen from an average of 70,000 barrels a year (b/y) during the pre-OPA period (1981-1990), to an average of 4,000 b/y since 1994, a 94% reduction (see Figure 1). FEW SPILLS - MOST NOT IN US WATERS THE NEW GLOBAL OIL MARKET, 1995, p.64 (BLUEOC 0866) The IMO estimates that worldwide accidental input of hydrocarbons by tankers into the marine environment is only about 12.1 percent of the total input, whereas input of hydrocarbons on account of municipal and industrial wastes and street runoffs contribute three times as much. Furthermore, tankers discharged more than twice the hydrocarbons into the world marine environment during operations than accidental spills did in 1990 (U.S. Coast Guard 1990). Out of 0.57 million ton s of oil that entered the marine environment as a result of accidental and operational losses, only 0.11 million tons, or 20 percent, were due to accidental spills, while 0.25 million tons were bilge and fuel oil (National Research Council 1991). Lloyd's Register (1990) reported that, overall, accidental spills remain random occurrences, and that less than 6 percent of worldwide marine accidents result in spills. It also reports that since the mid-1970's there have been far fewer spills in U.S. waters compared to the rest of the world. SPILLS ARE NO LONGER A THREAT Dan Walker, Ph.D., Ocean Studies Board, The National, NON-POINT SOURCE POLLUTION: REDUCING ITS IMPACT ON THE COASTAL ENVIRONMENT, September, 24, 2002, http://www.oceancommission.gov/meetings/sep24_25_02/walker_testimony.pdf (PDOCSS2973) New estimates reported in Oil in the Sea III indicate that spillage from vessels in North American waters from 1990 to 1999 was down by nearly two-thirds compared to the prior decade, and reductions in releases during oil and gas exploration and production have been dramatic as well. These releases, however, represent only about 30 percent of the worldwide petroleum inputs to the sea from human activity. Chronic low-level releases associated with the consumption of petroleum account for the other 70 percent and may pose significant risks to the sensitive estuarine environments where these inputs most often enter the marine environment. Volumetrically the most significant anthropogenic source of petroleum entering the marine environment is land-based, non-point source pollution, which delivers roughly 16 million gallons of petroleum to North American coastal waters each year, over half of the total anthropogenic load. Oceans resilient ---------------- OCEANS CAN ABSORB OIL Marc A. Mills, james S. Bonner, Department of Civil Engineering, Texas A&M University, Conrad Blucher Institute for Surveying and Science, Texas A&M University, 2003 (MARIN PRESS BULLETIN, February, p. in press) (PDOCSS693) The environment, having been exposed to petroleum inputs for thousands of years, can assimilate the hydrocarbons under the proper conditions. Efforts Save Birds ------------------ EFFORTS SAVE BIRDS MARINE POLICY, April 2003, p. ScienceDirect (WFU337) The successful rehabilitation of oiled seabirds requires high quality facilities and expert skills (including veterinary). Few oil spills occur where both are readily available, but in recent years there have been some relatively successful attempts to clean, rehabilitate, and release birds with the help of expert teams brought in from abroad. Spill Impacts On Fish Are Not Always Negative --------------------------------------------- NOT ALL SPILLS ARE THE SAME, FACTORS SUCH AS TYPES OF OIL, THE ENVIRONMENT AND THE STRENGTH OF THE ANIMAL DETERMINES SURVIVAL Dr. John Weins, Professor of Chemistry at Colorado State, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/wiens/introduction.html (BLUEOC 0888) Not all oil spills are the same, however, and the severity, extent, and duration of these effects are therefore variable and largely unpredictable. Differences in the kind of oil spilled, the time or season of release, the duration and extent of the spill, and weather conditions all affect the physical and toxicological properties of the oil. Differences among organisms in mobility, habitat preferences, and life-history traits affect the probability that individuals will encounter the oil. And differences in physiology, reproduction, feeding behavior, and diet determine the likelihood that encountering a spill will lead to mortality, reproductive failure, or physiological stress EFFECTS OF OIL SPILLS ARE NOT ALWAYS HORRIBLE, AND CAN ONLY BE SEEN AFTER YEARS OF DATA IS COLLECTED Dr. John Weins, Professor of Chemistry at Colorado State, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/wiens/conclusion.html (BLUEOC 0889) Several points emerge from the above accounts. The first (and most direct) is that reality is quite different from expectations. The four taxa we considered here - pink salmon, sea otters, harbor seals, and seabirds - are among those widely believed to have suffered severe impacts as a consequence of the spill. Our studies provide either no compelling evidence of initial impacts of the Exxon Valdez oil spill (pink salmon, roughly half of the seabird species we considered), suggestions that concerns about initial impacts may have been exaggerated (harbor seals), or indications that the resource was indeed affected by the spill but has recovered from these effects or that recovery is well underway (sea otters, half of the seabird species). These results speak to the resiliency of these species and of the larger marine ecosystem in PWS. SPILL IMPACTS ON FISH ARE NOT ALWAYS NEGATIVE Graham J. Edgar, Charles Darwin Research Station, Puerto Ayora, Galapágos, Ecuador, MARINE POLICY, April 2003, p. ScienceDirect (WFU338) Impacts on fish populations are not always negative, with Laur and Haldorson reporting increased densities of juvenile fishes amongst eelgrass beds following the Exxon Valdez oil spill, presumably as a consequence of either enhanced densities of epifaunal prey or reduced levels of predation. No Long-term Impact To Spills ----------------------------- THE NATURAL ENVIRONMENT CHANGES THE IMPACT OF SPILLS Dr. John Weins, Professor of Chemistry at Colorado State, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/wiens/conclusion.html (BLUEOC 0890) The second point follows from the first. The natural variability that promotes the resiliency of some components of these systems can severely compromise attempts to document spill impacts and subsequent recovery. If these systems were in a steady-state equilibrium, an impact would be recognized by a departure from that equilibrium, recovery by a return to it. In a variable system, such a fixed baseline is lacking, and the "target" of recovery is moving. Thus, the 1984 seabird surveys conducted by Irons et al. or the prespill surveys at harbor seal haulout sites represent realistic baselines for evaluating impacts to seabirds and their subsequent recovery or for calculating numbers of "missing seals" only if we assume that populations are in a long-term equilibrium about which they vary only moderately. Because the probability of occurrence of natural disturbances (e.g. El Niño events) increases over time, the effects of any single disturbance (e.g. an oil spill) become increasingly confounded by other sources of natural variation with increasing time since the spill event, and assessing recovery becomes more problematic. STANDARD TESTS MASSIVELY OVERESTIMATE OIL TOXICITY Charles Pace, Senior Environmental Scientist at Exxon Biomedical Sciences, 1995, PROCEEDINGS OF THE 1995 INTERNATIONAL OIL SPILL CONFERENCE ACHIEVING AND MAINTAINING PREPAREDNESS, February 27 - March 2, 1995, Long Beach, CA, p. 1003 (BLUEOC 0891) ABSTRACT: Standard aquatic toxicity tests do not address real-world, spiked exposure scenarios that occur during oil spills. We evaluated differences in toxicity of physically and chemically dispersed Kuwait crude oil to mysids (Mysidopsis bahia) under continuous and spiked (half-life of 2 hours) exposure conditions. The 96-hr LC50s for physically dispersed oil were 0.78 mg/L (continuous) and > 2.9 mg/L (spiked), measured as total petroleum hydrocarbons (TPH). Values for chemically dispersed oil were 0.98 mg/L (continuous) and 17.7 mg/L (spiked) TPH. Continuous-exposure tests may overestimate the potential for toxic effects under real-world conditions by a factor of 18 or more. STANDARD TESTS GREATLY EXAGGERATE OIL TOXICITY Charles Pace, Senior Environmental Scientist at Exxon Biomedical Sciences, 1995, PROCEEDINGS OF THE 1995 INTERNATIONAL OIL SPILL CONFERENCE ACHIEVING AND MAINTAINING PREPAREDNESS, February 27 - March 2, 1995, Long Beach, CA, p. 1004 (BLUEOC 0892) The toxicity of the WAF of a crude oil to a marine crustacean is highly dependent on the exposure duration used for test condition. Standard continuous-exposure toxicity test overestimate the toxicity of dispersant, physically dispersed oil and chemically dispersed oil by 18 to more than 38 times that seen under a more environmentally realistic spiked exposure scenario. The use of standard continuous-exposure toxicity test data to assess potential oil toxicity during spill situations provides an unrealistic characterization of the hazard posed to water column communities. MARINE ANIMALS SURVIVE SPILLS F.R. Engelhardt, Vice President for research and development at the Marine Response Corporation, 1994, Purposeful Jettison of Petroleum Cargo, p. 46 (BLUEOC 0893) Investigations of actual oil spill incidents have generally not been conclusive in identifying the toxicity of petroleum in seals or whales, even though mortality has been attributed to oil exposure at sea. Only some of the species have demonstrated a clear sensitivity to petroleum in experimental studies. Recent studies in seals, sea otters, polar bears, and whales have helped to round out the limited information base on the subject. Although the cetaceans at least are able to detect oil on the sea surface, it remains controversial if marine mammals would avoid oil spills at sea. In some circumstances both whale and seal species have been observed to surface through oil slicks. HISTORY PROVES ANIMALS WITHOUT SKIN ARE NOT AFFECTED BY OIL SPILLS Dr. David Page, Professor of Biochemistry at Bowdin College, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/baker/mammals_otters.html (BLUEOC 0894) Whales, porpoises and dolphins have no hair apart from a few bristles on the head or around the mouth (they rely on blubber under the skin for thermal insulation) and oil does not adhere to the skin. As with other blubber-bearing sea mammals, oil has little or no effect on cetaceans. All three of these species were exposed to floating oil after the Exxon Valdez spill, but there is no direct evidence that any of them were affected by it. STUDIES SHOW OIL SPILLS DON'T HURT SEA OTTERS Dr. David Page, Professor of Biochemistry at Bowdin College, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/baker/mammals_otters.html (BLUEOC 0895) Despite claims that sea otter populations were reduced in areas affected by the oil, censuses made in 1990 and 1991 suggest that numbers were fully restored either by immigration from unaffected areas or by increased breeding (Paine et al, 1996; Johnson & Garshelis, 1995). Despite the observed deaths following the oil spill, the evidence suggests that the sea otter population in Prince William Sound recovered quickly and suffered no long-term impact. EVIDENCE SHOWS SEA OTTER POPULATIONS INCREASE AFTER OIL SPILLS Dr. John Weins, Professor of Chemistry at Colorado State, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/wiens/otters.html (BLUEOC 0896) Postspill counts of independent sea otters at all four heavily oiled sites following the spill were at least as high as the last prespill counts conducted in 1984-85 (Figure 2). At Applegate Rock, prespill numbers declined from 1977 to 1985. After the spill, sea otter numbers increased significantly from 1990 to 1991 (Johnson and Garshelis 1995); since then, they have hovered around 44 otters, the number counted on the last prespill survey (A. M. Johnson, unpublished data). At Green Island, sea otter numbers were stable to slightly increasing from 1977 to 1985 (Figure 2). Average counts in 1990-91 were not significantly different from the prespill average (Johnson and Garshelis 1995), but the postspill trend has been positive. Sea otters at Knight Island increased significantly over their prespill numbers as early as 1991 (Johnson and Garshelis 1995) and have continued to increase into 1998 (Figure 2). Counts were not taken at Naked Island until 1993, at which time sea otters were more numerous (63 independent otters) than in 1985 (40 independent otters). Numbers have been increasing slowly since then, to 80 otters in 1998. SPILLS DIDN'T WIPE OUT SEA BIRDS Bjorn Lomborg Associate Professor of Statistics in the Political Science Dept of University of Aarhus, Denmark, 2001, THE SKEPTICAL ENVIRONMENTALIST: MEASURING THE REAL STATE OF THE WORLD, p 193 (BLUEOC 0897) Other scientists do not beat about the bush so much. John Wiens of Colorado State University says that it is "apparent that seabird populations were not devastated by the spill" and that "it now appears that the spill had few persistent or devastating long-term effects on seabirds."1452 Edward Gilfillan, who carried out the large-scale scientific investigation for Exxon, says that as early as "1990 between 73 and 91 percent of the area had recovered . OIL SPILLS DON'T EFFECT WHALES OR OTHER ANIMALS Dr. David Page, Professor of Biochemistry at Bowdin College, 1999 "TEN YEARS AFTER VALDEZ: AN ENVIRONMENTAL UPDATE http://www.valdezscience.com/baker/mammals_otters.html (BLUEOC 0898) Whales and other cetaceans can detect floating oil; gray whales (Eschrichtius robustus) surface and breathe less frequently when oil is on the water (Evans, 1982), but otherwise appear to ignore it; they passed through the Santa Barbara Channel, following the blow-out in 1969 while oil was on the water, without coming to harm (Straughan & Abbott, 1971).
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Title: Debate
Words: 12510
Rating: None
Pages: 50
submitted by: jellylizard
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