The 2009 State of the Climate report released
IN A DEPRESSING case of irony by juxtaposition, the death of climate change legislation in the Senate has been followed by the appearance of two government reports in the past week that underscore the overwhelming scientific case for global warming -- and go out of the way to repudiate skeptics.
First came a report on global climate from the National Oceanic and Atmospheric Administration, which confirmed that the 2000s were by far the warmest decade in the instrumental record -- as were, in their turns, the 1980s and the 1990s. Unlike year-to-year fluctuations, these 10-year shifts are statistically significant. Further, the report notes that it derived its conclusions from an array of data sources -- not just the land-surface readings that doubters challenge -- from ocean heat uptake to melting land ice to sea level rise.
"If the land surface records were systematically flawed and the globe had not really warmed, then it would be almost impossible to explain the concurrent changes in this wide range of indicators produced by many independent groups," the report said. "The warming of the climate system is unequivocal." The gases most likely responsible for that warming, such as carbon dioxide, continue to accumulate.
Second was a strongly worded response from the Environmental Protection Agency to petitions that it revoke its finding that "climate change is real, is occurring due to emissions of greenhouse gases from human activities and threatens human health and environment." As with much climate-change skepticism, the petitions were based "on selectively edited, out-of-context data and a manufactured controversy," EPA Administrator Lisa P. Jackson said. Among other things, the agency reviewed every document from the "Climategate" e-mail hack at a respected British climate research unit. The EPA found what four other independent studies did: that the e-mails contained some "candid" language but nothing that seriously discredits the scientific consensus on global warming.
Perhaps it is still too much to hope that Virginia Attorney General Ken Cuccinelli II will call off his misguided investigation of climate scientist Michael Mann, which seems to be based on the e-mail affair. Many climate-change skeptics will simply dismiss these reports as more evidence of a sprawling conspiracy instead of what they really are: yet more affirmation of the risks humanity runs if it continues to pump carbon into the atmosphere.
Report on global climate
The 2009 State of the Climate report released today draws on data for 10 key climate indicators that all point to the same finding: the scientific evidence that our world is warming is unmistakable. More than 300 scientists from 160 research groups in 48 countries contributed to the report, which confirms that the past decade was the warmest on record and that the Earth has been growing warmer over the last 50 years.
Based on comprehensive data from multiple sources, the report defines 10 measurable planet-wide features used to gauge global temperature changes. The relative movement of each of these indicators proves consistent with a warming world. Seven indicators are rising: air temperature over land, sea-surface temperature, air temperature over oceans, sea level, ocean heat, humidity and tropospheric temperature in the “active-weather” layer of the atmosphere closest to the Earth’s surface. Three indicators are declining: Arctic sea ice, glaciers and spring snow cover in the Northern hemisphere.
“For the first time, and in a single compelling comparison, the analysis brings together multiple observational records from the top of the atmosphere to the depths of the ocean,” said Jane Lubchenco, Ph.D., under secretary of commerce for oceans and atmosphere and NOAA administrator. “The records come from many institutions worldwide. They use data collected from diverse sources, including satellites, weather balloons, weather stations, ships, buoys and field surveys. These independently produced lines of evidence all point to the same conclusion: our planet is warming,”
The report emphasizes that human society has developed for thousands of years under one climatic state, and now a new set of climatic conditions are taking shape. These conditions are consistently warmer, and some areas are likely to see more extreme events like severe drought, torrential rain and violent storms.
“Despite the variability caused by short-term changes, the analysis conducted for this report illustrates why we are so confident the world is warming,” said Peter Stott, Ph.D., contributor to the report and head of Climate Monitoring and Attribution of the United Kingdom Met Office Hadley Centre. “When we look at air temperature and other indicators of climate, we see highs and lows in the data from year to year because of natural variability. Understanding climate change requires looking at the longer-term record. When we follow decade-to-decade trends using multiple data sets and independent analyses from around the world, we see clear and unmistakable signs of a warming world.”
While year-to-year changes in temperature often reflect natural climatic variations such as El Niño/La Niña events, changes in average temperature from decade-to-decade reveal long-term trends such as global warming. Each of the last three decades has been much warmer than the decade before. At the time, the 1980s was the hottest decade on record. In the 1990s, every year was warmer than the average of the previous decade. The 2000s were warmer still.
“The temperature increase of one degree Fahrenheit over the past 50 years may seem small, but it has already altered our planet,” said Deke Arndt, co-editor of the report and chief of the Climate Monitoring Branch of NOAA’s National Climatic Data Center. “Glaciers and sea ice are melting, heavy rainfall is intensifying and heat waves are more common. And, as the new report tells us, there is now evidence that over 90 percent of warming over the past 50 years has gone into our ocean.”
More and more, Americans are witnessing the impacts of climate change in their own backyards, including sea-level rise, longer growing seasons, changes in river flows, increases in heavy downpours, earlier snowmelt and extended ice-free seasons in our waters. People are searching for relevant and timely information about these changes to inform decision-making about virtually all aspects of their lives. To help keep citizens and businesses informed about climate, NOAA created the Climate Portal at http://www.climate.gov. The portal features a short video that summarizes some of the highlights of the State of the Climate Report.
Denial of Petitions for Reconsideration of the Endangerment and Cause or Contribute Findings for Greenhouse Gases under Section 202(a) of the Clean Air Act
EPA determined in December 2009 that climate change caused by emissions of greenhouse gases threatens the public's health and the environment. Since then, EPA received ten petitions challenging this determination. On July 29, 2010, EPA denied these petitions.
The petitions to reconsider EPA's "Endangerment Finding" claimed that climate science can't be trusted, and asserted a conspiracy that calls into question the findings of the Intergovernmental Panel on Climate Change (IPCC) Exit EPA disclaimer, the U.S. National Academy of Sciences Exit EPA disclaimer, and the U.S. Global Change Research Program. After months of serious consideration of the petitions and of the state of climate change science, EPA found no evidence to support these claims.
The scientific evidence supporting EPA's finding is robust, voluminous, and compelling. Climate change is happening now, and humans are contributing to it. Multiple lines of evidence show a global warming trend over the past 100 years. Beyond this, melting ice in the Arctic, melting glaciers around the world, increasing ocean temperatures, rising sea levels, altered precipitation patterns, and shifting patterns of ecosystems and wildlife habitats all confirm that our climate is changing.
Source and Credits : washingtonpost.com, National Oceanic and Atmospheric Administration and www.epa.gov
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