Atlantic Acropora Status Review March 3, 2005
Text and Images describing status of Acropora corals prior to their designation as a threatened species under the US Endangered Species Act.
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Stormwater Journal: Landmark USGS Survey Demonstrates How Methylmercury, known to Contaminate Seafood, Originates in the Ocean
Landmark U.S. Geological Survey Study Demonstrates How Methylmercury, Known to Contaminate Seafood, Originates in the Ocean,
Published May 4, 2009 in Stormwater, the Journal for Surface Water Quality Professionals
(Washington, D.C. – May 1, 2009) A new landmark study published today documents for the first time the process in which increased mercury emissions from human sources across the globe, and in particular from Asia, make their way into the North Pacific Ocean and as a result contaminate tuna and other seafood. Because much of the mercury that enters the North Pacific comes from the atmosphere, scientists have predicted an additional 50 percent increase in mercury in the Pacific by 2050 if mercury emission rates continue as projected.
“This unprecedented USGS study is critically important to the health and safety of the American people and our wildlife because it helps us understand the relationship between atmospheric emissions of mercury and concentrations of mercury in marine fish,” said Secretary of the Interior Ken Salazar. “We have always known that mercury can pose a risk, now we need to reduce the mercury emissions so that we can reduce the ocean mercury levels.”
“This study gives us a better understanding of how dangerous levels of mercury move into our air, our water, and the food we eat, and shines new light on a major health threat to Americans and people all across the world,” said EPA Administrator Lisa P. Jackson. “With this information in hand, plus our own mercury efforts, we have an even greater opportunity to continue working with our international partners to significantly cut mercury pollution in the years ahead and protect the health of millions of people.”
Water sampling cited in the study shows that mercury levels in 2006 were approximately 30 percent higher than those measured in the mid-1990s. This study documents for the first time the formation of methylmercury in the North Pacific Ocean. It shows that methylmercury is produced in mid-depth ocean waters by processes linked to the “ocean rain.” Algae, which are produced in sunlit waters near the surface, die quickly and “rain” downward to greater water depths. At depth, the settling algae are decomposed by bacteria and the interaction of this decomposition process in the presence of mercury results in the formation of methylmercury. Many steps up the food chain later, predators like tuna receive methylmercury from the fish they consume.
One unexpected finding from this study is the significance of long-range transport of mercury within the ocean that originates in the western Pacific Ocean, off the coast of Asia.
“Mercury researchers typically look skyward to find a mercury source from the atmosphere due to emissions from land-based combustion facilities. In this study, however, the pathway of the mercury was a little different. Instead, it appears the recent mercury enrichment of the sampled Pacific Ocean waters is caused by emissions originating from fallout near the Asian coasts. The mercury-enriched waters then enter a long-range eastward transport by large ocean circulation currents,” said USGS scientist and coauthor David Krabbenhoft.
Scientists sampled Pacific Ocean water from 16 different sites between Honolulu, Hawaii and Kodiak, Alaska. In addition, the scientists constructed a computer simulation that links atmospheric emissions, transport and deposition of mercury, and an ocean circulation model.
In the United States, about 40 percent of all human exposure to mercury is from tuna harvested in the Pacific Ocean, according to Elsie Sunderland, a coauthor of the study. Methylmercury is a highly toxic form of mercury that rapidly accumulates in the food chain to levels that can cause serious health concerns for those who consume the seafood. Pregnant women who consume mercury can pass on life-long developmental effects to their children. That is why in 2004 EPA and FDA issued the landmark Joint Guidance on the Consumption of Fish specifically targeted towards pregnant women and nursing mothers. Previous studies show that 75 percent of human exposure worldwide to mercury is from the consumption of marine fish and shell fish.
Scientists have known for some time that mercury deposited from the atmosphere to freshwater ecosystems can be transformed (methylated) into methylmercury, but identifying the analogous cycles in marine systems has remained elusive. As a result of this study we now know more about how the process which leads to the transformation of mercury into methylmercury.
The paper, “Mercury sources, distribution and bioavailability in the North Pacific Ocean–Insights from data and models and information on other USGS mercury research,” is available at: http://toxics.usgs.gov/highlights/pacific_mercury.html
The study appeared today in Global Biogeochemical Cycles, which is published by the American Geophysical Union. In addition to USGS mercury expert David Krabbenhoft, the authors include Elsie Sunderland, Harvard University; John Moreau, University of Melbourne, Australia (until recently a USGS, NRC Post Doctoral Candidate); William Landing, Florida State University; and Sarah Strode, Harvard University.
Pew Research Center: Fewer Americans See Evidence of Global Warming
http://people-press.org/report/556/global-warming
Overview
There has been a sharp decline over the past year in the percentage of Americans who say there is solid evidence that global temperatures are rising. And fewer also see global warming as a very serious problem – 35% say that today, down from 44% in April 2008.
The latest national survey by the Pew Research Center for the People & the Press, conducted Sept. 30-Oct. 4 among 1,500 adults reached on cell phones and landlines, finds that 57% think there is solid evidence that the average temperature on earth has been getting warmer over the past few decades. In April 2008, 71% said there was solid evidence of rising global temperatures.
Over the same period, there has been a comparable decline in the proportion of Americans who say global temperatures are rising as a result of human activity, such as burning fossil fuels. Just 36% say that currently, down from 47% last year.
The decline in the belief in solid evidence of global warming has come across the political spectrum, but has been particularly pronounced among independents. Just 53% of independents now see solid evidence of global warming, compared with 75% who did so in April 2008. Republicans, who already were highly skeptical of the evidence of global warming, have become even more so: just 35% of Republicans now see solid evidence of rising global temperatures, down from 49% in 2008 and 62% in 2007. Fewer Democrats also express this view – 75% today compared with 83% last year.
Despite the growing public skepticism about global warming, the survey finds more support than opposition for a policy to set limits on carbon emissions. Half of Americans favor setting limits on carbon emissions and making companies pay for their emissions, even if this may lead to higher energy prices; 39% oppose imposing limits on carbon emissions under these circumstances.
This issue has not registered widely with the public. Just 14% say they have heard a lot about the so-called “cap and trade” policy that would set carbon dioxide emissions limits; another 30% say they have heard a little about the policy, while a majority (55%) has heard nothing at all.
The small minority that has heard a lot about the issue opposes carbon emissions limits by two-to-one (64% to 32%). More Republicans (20%) and independents (17%) than Democrats (8%) have heard a lot about cap and trade. Among the much larger group that has heard little or nothing about the issue, most support it (58% little, 50% nothing).
With less than two months before the United Nations Climate Change Conference in Copenhagen, a majority (56%) of Americans think the United States should join other countries in setting standards to address global climate change while 32% say that the United States should set its own standards.
Shifts on Global Warming
Opinions about global warming changed little between 2006 and 2008. In August 2006 and January 2007, 77% said there was solid evidence that the earth’s temperatures were increasing; that figure fell modestly to 71% in April of last year.
Among those who saw solid evidence of global warming, most said it was largely caused by human activity, such as burning fossil fuels; in all three of those surveys, 47% of the public expressed this view. Far smaller percentages – including just 18% in 2008 – said it was mostly caused because of natural environmental patterns.
Currently, 57% say there is solid evidence of rising global temperatures, while 33% say there is no solid evidence. Fewer than four-in-ten (36%) now say global warming is mostly caused by human activity such as burning fossil fuels, while 16% say it is occurring mostly because of natural environmental patterns.
A majority (53%) of independents say there is solid evidence of warming, including 33% who say it is mostly caused by human activity. But this is far lower than in April 2008 when 75% said global warming was happening and 50% said it was due to human activity.
The proportion of Republicans saying there is solid evidence of global warming declined from 62% in 2007 to 49% in 2008. The balance of opinion among Republicans has shifted, with a majority (57%) now saying there is no hard evidence of global warming. The drop among moderate and liberal Republicans has been particularly steep; 41% now say there is solid evidence of global warming, compared with 69% last year. The decline among conservative Republicans has been more modest (from 43% to 32%).
There has been less change in opinions among Democrats. Three-quarters of Democrats (75%) say there is solid evidence the earth is warming, including 50% who say that it is mostly because of human activity. In April 2008, 83% of Democrats said the earth is warming and 58% attributed it to human actions. More liberal Democrats than conservative and moderate Democrats say the earth is warming (83% vs. 72%), and far more liberal Democrats say that global warming is caused by human activity (69% vs. 43%).
There also are strong regional differences in opinions about global warming; fewer people living in the Mountain West (44%) and the Midwest (48%) say there is solid evidence of warming than in other regions. Similarly, there have been sharp declines since April 2008 in the proportion who say the earth is warming in the Mountain West (75% to 44%) and the Great Lakes region (69% to 49%). Both regions have also seen large drops in the percentage who say that warming is caused by human activity. (For a breakdown of states and regions, see About the Survey, pg. 10.)
Fewer See Warming as Very Serious Problem
A majority (65%) of the public continues to view global warming as a very (35%) or somewhat (30%) serious problem. But in April 2008, 73% expressed this view, including 44% who thought it was a very serious problem. About a third (32%) says global warming is not too serious (15%) or not a problem at all (17%). Last year, 24% said it was little or no problem. From 2006 to 2008, these numbers had been quite stable.
Partisan differences also are evident on evaluations of the seriousness of global warming. About half (49%) of Democrats say global warming is a very serious problem, down from 57% in April 2008. Far fewer conservative and moderate Democrats say global warming is a serious problem than did so last year, widening the gap between them and liberal Democrats. Currently, 39% of conservative and moderate Democrats say it is a very serious problem compared with 70% of liberal Democrats. A third of independents now say global warming is a very serious problem, a decline of 13 points from last year.
Only 14% of Republicans say that global warming is a very serious problem, down from 22% in April 2008. Just 20% of moderate and liberal Republicans now say that global warming is a very serious problem, down from 35% last year. Only 10% of conservative Republicans now say global warming is a very serious problem.
People living in the Midwest (30%) and the Mountain West (26%) are the least likely to view global warming as a very serious problem. There have been modest declines across regions, but they are particularly steep in the West (52% April 2008 to 36% now).
Young people are now far more likely than older Americans to view global warming as a very serious problem. Across all age groups, except those younger than 30, the percent who think warming is a very serious problem has declined since April 2008.
As expected, views about the seriousness of global warming are also related to whether people think there is solid evidence the earth is warming and whether it is human caused. A third of those who do not think there is solid evidence of global warming say it is a very or somewhat serious problem while 65% say it is not too serious or not a problem at all.
By comparison 65% of those who say that the warming is mostly caused by natural patterns in the earth’s environment say global warming is at least a somewhat serious problem. Nearly all (97%) who think the earth is warming mostly because of human activity say it is a problem. These numbers are largely unchanged from April 2008.
In January 2009, global warming ranked at the bottom of the public’s list of policy priorities for the president and Congress this year. Only 30% of the public said it should be a top priority, down from 35% a year ago. More than twice as many Democrats (45%) as Republicans (16%) rank global warming as a top priority, along with 25% independents. Global warming is the lowest-rated priority for both independents and Republicans and ranks sixteenth for Democrats among 20 issues. (Economy, Jobs Trump All Other Policy Priorities in 2009 Jan. 22).
Cap and Trade Barely Registers
As the health care debate has dominated the public’s attention, awareness about cap and trade legislation is quite low. A majority (55%) of the public has heard nothing at all about the cap and trade policy being considered by the president and Congress that would set limits on carbon dioxide emissions. Only 14% have heard a lot and 30% a little about this policy.
More Republicans (20%) and independents (17%) than Democrats (8%) have heard a lot about cap and trade although more Democrats have heard a little. Conservative Republicans are hearing the most; more than a quarter have heard a lot (28%) about the policy.
More people who say there is no solid evidence of global warming have heard a lot about cap and trade than those who think temperatures are rising (24% vs. 10%). But more of those who say that warming is caused mostly by human activity have heard a little about the proposed policy than those who say there is no evidence of warming (36% vs. 27%).
The most recent survey of the public’s knowledge by the Pew Research Center, released Oct. 14, found that just 23% of the public could correctly identify that the cap and trade legislation being discussed in Congress deals with energy and the environment; 48% were unsure and 29% said incorrectly that it deals with health care, banking reform or unemployment. More Republicans (27%) and independents (29%) correctly identify cap and trade as dealing with energy and the environment than Democrats (15%). (See Well Known: Public Option, Sonia Sotomayor; Little Known: Cap and Trade, Max Baucus).
Carbon Emissions Limits Favored
Half of the public favors setting limits on carbon dioxide emissions and making companies pay for their emissions, even if it may mean higher energy prices. About four-in-ten (39%) oppose this and 11% are unsure or do not offer an opinion.
Conservative Republicans are the only political group in which a majority (60%) opposes setting limits on carbon dioxide emissions. Most moderate and liberal Republicans (51%) favor this policy, as do an identical percentage of independents and a majority of Democrats (58%).
There also are wide regional differences in opinions about cap and trade. More people living near the Pacific coast (62%) and the Northeast (56%) favor limiting carbon emissions, even if it may mean higher energy prices than those living in the South (46%), Midwest (44%) and Mountain West (42%). More college graduates favor this policy than those with a high school education or less (59% vs. 43%), but there are very few differences by age.
Opinion about cap and trade is related to views about global warming. About three-fourths (74%) of those who think the earth is warming and it is mostly caused by human activity favor cap and trade legislation. By comparison, 41% of those who say warming is due to natural patterns in the earth’s environment favor limiting carbon emissions. But even 31% of those who say there is no solid evidence of rising temperatures favor cap and trade.
Public Supports Global Initiatives
A majority (56%) of Americans thinks the United States should join other countries in setting standards to address global climate change while 32% say the U.S. should set its own standards; 5% say neither and 6% are unsure. These numbers are similar to those in 2001 and 1997 when the public was asked about setting standards to improve the global environment.
More Democrats (66%) than independents (53%) or Republicans (47%) say the U.S. should join other countries in setting standards to address global climate change. Three-quarters of those who say the earth is warming mostly because of human activity think the U.S. should join with other countries in setting standards to address global climate change. By comparison, 51% of those who say warming is due to natural patterns in the earth’s environment and 42% who say the earth is not warming think the U.S. should join other countries in setting standards to address climate change.
Report Materials–see link above
About the Survey: Results for this survey are based on telephone interviews conducted under the direction of Abt/SRBI Inc. among a nationwide sample of 1,500 adults, 18 years of age or older, from September 30-October 4, 2009 (1125 respondents were interviewed on a landline telephone, and 375 were interviewed on a cell phone, including 141 who had no landline telephone). Both the landline and cell phone samples were provided by Survey Sampling International. Interviews were conducted in English. For detailed information about our survey methodology, see http://people-press.org/methodology/.
The combined landline and cell phone sample are weighted using an iterative technique that matches gender, age, education, race/ethnicity, region, and population density to parameters from the March 2008 Census Bureau’s Current Population Survey. The sample is also weighted to match current patterns of telephone status and relative usage of landline and cell phones (for those with both), based on extrapolations from the 2008 National Health Interview Survey. The weighting procedure also accounts for the fact that respondents with both landline and cell phones have a greater probability of being included in the combined sample and adjusts for household size within the landline sample.
The following table (go to link above) shows the error attributable to sampling that would be expected at the 95% level of confidence for different groups in the survey:
In addition to sampling error, one should bear in mind that question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of opinion polls.
For the regional analysis used in this report, states were grouped into smaller subregions or divisions.
ABOUT THE CENTER
The Pew Research Center for the People & the Press is an independent opinion research group that studies attitudes toward the press, politics and public policy issues. We are sponsored by The Pew Charitable Trusts and are one of seven projects that make up the Pew Research Center, a nonpartisan “fact tank” that provides information on the issues, attitudes and trends shaping America and the world.
The Center’s purpose is to serve as a forum for ideas on the media and public policy through public opinion research. In this role it serves as an important information resource for political leaders, journalists, scholars, and public interest organizations. All of our current survey results are made available free of charge.
All of the Center’s research and reports are collaborative products based on the input and analysis of the entire Center staff consisting of:
Andrew Kohut, Director
Scott Keeter, Director of Survey Research
Carroll Doherty and Michael Dimock, Associate Directors
Michael Remez, Senior Writer
Robert Suls, Shawn Neidorf, Leah Christian and Jocelyn Kiley, Research Associates
Alec Tyson, Research Analyst
UNEP Climate Change Science Compendium 2009
http://www.unep.org/compendium2009/
Climate Change Science Compendium 2009
The Climate Change Science Compendium is a review of some 400 major scientific contributions to our understanding of Earth Systems and climate that have been released through peer-reviewed literature or from research institutions over the last three years, since the close of research for consideration by the IPCC Fourth Assessment Report.
The Compendium is not a consensus document or an update of any other process. Instead, it is a presentation of some exciting scientific findings, interpretations, ideas, and conclusions that have emerged among scientists.
Focusing on work that brings new insights to aspects of Earth System Science at various scales, it discusses findings from the International Polar Year and from new technologies that enhance our abilities to see the Earth’s Systems in new ways. Evidence of unexpected rates of change in Arctic sea ice extent, ocean acidification, and species loss emphasizes the urgency needed to develop management strategies for addressing climate change.
An up-dated version of the Climate Change Science Compendium 2009 was uploaded to the Internet on 21 October 2009. It follows feed-back from researchers, experts and members of the public following the launch last month. UNEP welcomes further constructive comments so that the report evolves as a living document containing the latest peer-reviewed science.
Peter Gilruth, Director Division of Early Warning and Assessment
Climate Change Coral Bleaching and the Future of the World’s Coral Reefs
http://www.greenpeace.org/australia/resources/reports/climate-change/climate-change-coral-bleachin
Climate Change Coral Bleaching
Ove Hoegh-Gulberg, Foundation Professor
Marine Studies, University of Queensland
EXECUTIVE SUMMARY
Sea Temperatures in the tropics have increased by almost 1 degree Centigrade over the past 100 years and are currently increasing at the rate of 1-2 degrees Centigrade per century. Reef-building corals, which are central to healthy coral reefs, are currently living close to their upper thermal limit. They become stressed if exposed to small slight increases (1-2 degrees Centigrade) in water and experience coral bleaching.
Coral bleaching occurs when the photosynthetic symbionts of corals (zooxanthellae) become increasingly vulnerable to damage from light at higher than normal temperatures. The resulting damage leads to the expulsion of these important organisms from the coral host. Corals tend to die in great numbers following coral bleaching events, which may stretch across thousands of square kilometers of ocean. Bleaching events in 1998, the worst on record, saw the complete loss of live coral from some reefs in some parts of the world.
This paper reviews our understanding of coral bleaching and demonstrates that the current increase in the intensity and extent of coral bleaching is due to the increasing sea temperature. Importantly, this paper uses the output from four different models to project how the frequency and intensity of bleaching events are likely to change over the next hundred years if greenhouse gas emissions are not reduced. The results of this analysis are startling and a matter of great concern. Sea temperatures calculated by all model projections show that the thermal tolerances of reef-building corals are likely to be exceeded within the next few decades. As a result of these increases, bleaching events are set to increase in frequency and intensity. Events as severe as the 1998 event could become commonplace within twenty years. Bleaching events are very likely to occur annually in most tropical oceans by the end of the next 30-50 years.
There is little doubt among coral reef biologists that an increase in the frequency of bleaching events of this magnitude could have drastic consequences for coral reefs everywhere. Arguments that corals will acclimate to predicted patterns of temperature change are unsubstantiated and evidence suggests that the genetic ability of corals to acclimate is already being exceeded. Corals may adapt in evolutionary time, but such changes are expected to take hundreds of years, suggesting that the quality of the world’s reefs will decline at rates that are faster than are expected.
Every coral reef examined in Southeast Asia, the Pacific and Caribbean showed the same trend. The world’s largest continuous reef system (Australia’s Great Barrier reef) was no exception and could face severe bleaching events every year by the year 2030. Southern and central sites of the Great Barrier Reef are likely to be severely affected by sea temperature rise within the next twenty to forty years. Northern sites are warming more slowly and are expected to lag behind changes in the southern end of the Great Barrier Reef by twenty years. In summary, the rapidity and extent of these projected changes, if realized, spells catastrophe for tropical marine ecosystems everywhere and suggests that unrestrained warming cannot occur without the complete loss of coral reefs on a global scale.