This page contains links to pages discussing the emission of greenhouse gases into the atmosphere.
"Our data clearly shows a break point in 1982, where the entire growth
patterns of the trees in this forest started on a different trajectory,"
Nippert said. "It took 10 years for that landmark environmental
legislation to reduce sulfur dioxide emissions, but it eventually did.
When it did, we saw an entire ecosystem recover from years of acidic
pollution."
Right now, if businesses or environmental officials need to estimate the
impact of different greenhouse gas (GHG) reduction measures in one
country or region of North America compared to another, they face
multiple GHG reporting regimes with varying levels of detail and
complexity.
Outgoing environment minister A Raja has said India was among the lowest polluters with emission levels of four per cent. Blaming the developed countries for being major contributors to global warming, he said India was mobilising the developing nations to protest against the high emissions levels of the USA-led affluent countries. [posted by the Hindustan Times (online) on May 20, 2007]
The newest analysis of trace gases trapped in Antarctic ice cores now provide a reasonable view of greenhouse gas concentrations as much as 800,000 years into the past, and are further confirming the link between greenhouse gas levels and global warming, scientists reported May 14 in the journal Nature.
The United Nations on Wednesday launched a web portal [http://www.cdmbazaar.net] to spur a market-driven trading service designed to help cut greenhouse gas emissions under the Kyoto Protocol.
These climate changes, the statement says, are “best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century.”
The findings, just published in the online edition of the journal Science, shed further light on the fluctuations in greenhouse gases and climate in Earth’s past, and appear to confirm the validity of the types of computer models that are used to project a warmer climate in the future, researchers said.
How can we be sure that humans are responsible for these increases? Some greenhouse gases (most of the halocarbons, for example) have no natural source. For other gases, two important observations demonstrate human influence. First, the geographic differences in concentrations reveal that sources occur predominantly over land in the more heavily populated Northern Hemisphere. Second, analysis of isotopes, which can distinguish among sources of emissions, demonstrates that the majority of the increase in carbon dioxide comes from combustion of fossil fuels (coal, oil and natural gas). Methane and nitrous oxide increases derive from agricultural practices and the burning of fossil fuels.
The threat of global warming can still be greatly diminished if nations cut emissions of heat-trapping greenhouse gases by 70 percent this century, according to a new analysis. While global temperatures would rise, the most dangerous potential aspects of climate change, including massive losses of Arctic sea ice and permafrost and significant sea level rise, could be partially avoided.
Researchers from Brown University and the University of Washington have found a new way to make the link. The scientists show that comparing nitrogen isotopes in their deposited form — nitrates — can reveal the sources of atmospheric nitric oxide. In a paper published June 5 in Science, the group traces the source of nitrates to nitric oxides released through fossil fuel burning that parallels the beginning of the Industrial Revolution. The group also reveals that the greatest change in nitrogen isotope ratios occurred between 1950 and 1980, following a rapid increase in fossil fuel emissions.
Observations show that the tropics have widened by 0.7 degrees latitude per decade, with warming from greenhouse gases also contributing to the expansion in both hemispheres. To study this expansion, the researchers first compared observational data with simulated data from climate models for 1979-1999. The simulated data were generated by a collection of 20 climate models called the Coupled Model Intercomparison Project version 3 or "CMIP3."
These eruptions are known as super-eruptions because they are more than 100 times the size of ordinary volcanic eruptions like Mount St. Helens. They spew out tremendous flows of super-heated gas, ash and rock capable of blanketing entire continents and inject enough particulate into the stratosphere to throw the global climate into decade-long volcanic winters. In fact, there is evidence that one super-eruption, which took place in Indonesia 74,000 years ago, may have come remarkably close to wiping out the entire human species.
Giant volcanic eruptions in Nicaragua over the past 70,000 years could have injected enough gases into the atmosphere to temporarily thin the ozone layer, according to new research. And, if it happened today, a similar explosive eruption could do the same, releasing more than twice the amount of ozone-depleting halogen gases currently in stratosphere due to humanmade emissions.
Clouds of pollution over the Indian Ocean appear to cause as much warming as greenhouse gases released by human activity, a study has suggested.
The European Union implemented a cap and trade scheme in 2005 to help it fulfil its obligations under the first phase of the Kyoto Protocol for reducing carbon emissions. The Scandinavian nations had independently imposed a carbon tax in the 1990s as part of their effort to reduce carbon emissions. US researchers have tracked the carbon disclosures from both regions of Europe and found that neither the EU's carbon allocation scheme nor Scandinavia's carbon taxes have made any significant impact on reducing greenhouse gas emissions.
Rising sea levels cannot be stopped over the next several hundred years, even if deep emissions cuts lower global average temperatures, but they can be slowed down, climate scientists said in a study on Sunday. (posted by NewsDaily for July 1, 2012)
Researchers at the University of Wisconsin-Madison and Rutgers University have found that the climate effects of a hypothetical nuclear war between India and Pakistan would greatly reduce yields of staple crops, even in distant countries.
A U of S-led international research team has discovered that aerosols from relatively small volcanic eruptions can be boosted into the high atmosphere by weather systems such as monsoons, where they can affect global temperatures. The research appears in the July 6 issue of the journal Science.
A debate has raged in the past couple of years as to whether natural gas is better or worse overall than coal and oil from a global warming perspective. The back-and-forth findings have been due to the timelines taken into consideration, the details of natural gas extraction, and the electricity-generating efficiency of various fuels. An analysis by Cathles, which focuses exclusively on potential warming and ignores secondary considerations, such as economic, political, or other environmental concerns, finds that natural gas is better for electricity generation than coal and oil under all realistic circumstances.
As reported in a paper published in the July 27 issue of Science, a team of researchers led by James G. Anderson, the Philip S. Weld Professor of Atmospheric Chemistry, are warning that a newly-discovered connection between climate change and depletion of the ozone layer over the U.S. could allow more damaging ultraviolet (UV) radiation to reach the Earth's surface, leading to increased incidence of skin cancer.
"The reason is simple: Cars are getting cleaner," said Carsten Warneke, Ph.D., a NOAA-funded scientist with the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder.
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