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News
- -03-27-06 Is It Too Late to Stop Global Warming? (ABC News)
"A prime example: decayed vegetation in the Arctic, which contains massive amounts of carbon, used to be protected by the perpetual cold. As the climate warms — sped along by human beings burning fossil fuels that release carbon dioxide — scientists say the vegetation will dry out and break down, releasing even more carbon dioxide."
" 'Humans are putting about 6 or 7 billion metric tons of carbon in the atmosphere a year, and we're standing on 200 billion tons here," says [biologist Walter] Oechel. 'Any significant portion comes out, that's worse than current human injection into the atmosphere. And once that runaway release occurs, there would be no way to stop it.' " 03-06
- -05-21-09 Beyond the Worst Case Scenario (Scientific American)
"The IPCC has declared man-made climate change 'unequivocal.' The hard part: trying to stop it." 05-09
- -05-21-09 How Much Carbon Is Too Much? (Scientific American)
"To avoid catastrophic climate change, the world will need to emit less than one trillion metric tons of carbon between now and 2050, according to two new papers published in Nature today. In other words, there is only room in the atmosphere to burn or vent less than one quarter of known oil, natural gas and coal reserves."
Editor's Note: One alternative is to "pull carbon from the air and store it in the soil. See biochar. 05-09
- -05-21-09 Special Report: Climate Change (Scientific American)
"The Intergovernmental Panel on Climate Change (IPCC) has just completed its fourth assessment of the science of climate change, its impacts and possible solutions. The panel of 2,500 scientists and other experts declared manmade warming 'unequivocal' and wrote that it could lead to climate changes that are 'abrupt and irreversible.' " 05-09
- -09-25-06 Global Warming Nears "Dangerous Levels" (MSNBC News)
"Global temperatures are dangerously close to the highest ever estimated to have occurred in the past million years, scientists reported Monday." 09-06
- Carbon Emissions Need to Go "Negative" by 2050 (Planet2025News.net)
"A chapter by climate scientist W. L. Hare concludes that in order to avoid a catastrophic climate tipping point, global greenhouse gas emissions will need to peak before 2020 and drop 85 percent below 1990 levels by 2050, with further reductions beyond that date. Emissions of carbon dioxide would actually need to ‘go negative’—with more being absorbed than emitted—during the second half of this century. Hare’s research finds that even a warming of 2 degrees Celsius poses unacceptable risks to key natural and human systems, including significant loss of species, major reductions in food-production capacity in developing countries, severe water stress for hundreds of millions of people, and significant sea-level rise and coastal flooding." 01-09
Papers
- -Editorial: Our Threatened Oceans (Awesome Library)
"We have reason for great concern that our oceans are going through a rapid change that may create severe problems for ourselves and disaster for our children and grandchildren. Here are some of the problems...." 01-06
- -Editorial: Where Is the Tipping Point for Disaster? (Time.com)
"When asked to quantify the impact of climate change, scientists come up with a lot of interesting answers, no two of them quite the same. For the lay person, then, perhaps the simplest way to understand it is to imagine a distant asteroid, somewhere out in space, on a collision course with Earth. It's not clear when or where the asteroid will hit, or exactly how severe the consequences will be. But it is clear that when it happens, the consequences will be far worse — and last far longer — than any natural disaster humanity has ever known." 03-09
- -How Much Carbon Is Too Much? (Nature.com)
"More than 100 countries have adopted a global warming limit of 2 °C or below (relative to pre-industrial levels) as a guiding principle for mitigation efforts to reduce climate change risks, impacts and damages1, 2." 05-09
- Atlantic Ocean Heat Conveyor Currents (CLIVAR.org)
"The oceanic heat transport in the Atlantic Ocean has an obvious and well-known impact on climate. Most of the heat transport in this basin is a consequence of the warm-to-cold water conversion associated with the thermohaline circulation. Fig. 7.1 shows the main northward flowing warm water routes and the cold deep southward return flows that form the North Atlantic thermohaline circulation." 01-06
- Ocean Currents Already Changing (Scientific American)
"A paper in this week's issue of Nature reveals that the Gulf Stream current system--a band of water that brings tropical warmth to the North Atlantic, keeping Europe from being as cold as it should be--circulates 30 percent less water than it did in the past." 12-05
- Oceanic Conveyor (Woods Hole Oceanic Institute)
"Evidence for abrupt climate change is readily apparent in ice cores taken from Greenland and Antarctica. One sees clear indications of long-term changes discussed above, with CO˛ and proxy temperature changes associated with the last ice age and its transition into our present interglacial period of warmth. But, in addition, there is a strong chaotic variation of properties with a quasi-period of around 1500 years. We say chaotic because these millennial shifts look like anything but regular oscillations. Rather, they look like rapid, decade-long transitions between cold and warm climates followed by long interludes in one of the two states." Includes an animation showing the global oceanic conveyor of warm and cool currents. 01-06
- Scientists: Arctic Ice Loss Triggering Global Warming (BBC News)
" 'September 2005 will set a new record minimum in the amount of Arctic sea ice cover,' said Mark Serreze, of the National Snow and Ice Data Center (NSIDC), Boulder, Colorado.' "
"The current rate of shrinkage they calculate at 8% per decade; at this rate there may be no ice at all during the summer of 2060."
" 'These dark areas absorb a lot of the Sun's energy, much more than the ice, and what happens then is that the oceans start to warm up, and it becomes very difficult for ice to form during the following autumn and winter.' "
" 'It looks like this is exactly what we're seeing - a positive feedback effect, a "tipping-point".' "
"The idea behind tipping-points is that at some stage the rate of global warming would accelerate, as rising temperatures break down natural restraints or trigger environmental changes which release further amounts of greenhouse gases."
"The Arctic Climate Impact Assessment, a four-year study involving hundreds of scientists, projected an additional temperature rise of 4-7C by 2100." 9-05
- U.N.: 2005 Set Record for Greenhouse Gases (MSNBC News)
"Greenhouse gases in the Earth's atmosphere reached a high in 2005 and are still increasing, the U.N. weather agency said Friday." 11-06
- Warming Debate Shifts to "Tipping Point" (MSNBC News)
"Now that most scientists agree human activity is causing Earth to warm, the central debate has shifted to whether climate change is progressing so rapidly that, within decades, humans may be helpless to slow or reverse the trend."
"There are three specific events that these scientists describe as especially worrisome and potentially imminent, although the time frames are a matter of dispute: widespread coral bleaching that could damage the world's fisheries within three decades; dramatic sea level rise by the end of the century that would take tens of thousands of years to reverse; and, within 200 years, a shutdown of the [Atlantic thermohaline] ocean current that moderates temperatures in northern Europe." 01-06
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© 2009 EDI
and Dr. R. Jerry Adams
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