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Title: Widespread Arctic Wildlife Changes Seen with Global Warming
Source:
VOANews
URL Source: http://www.voanews.com/english/2009-09-11-voa1.cfm
Published: Sep 11, 2009
Author: Jessica Berman
Post Date: 2009-09-12 16:01:09 by buckeroo
Keywords: None
Views: 493
Comments: 47
Scientists carying out studies of wildlife in the Arctic say global warming is causing dramatic changes in animal and plant life, threatening some species with extinction. The report is a compilation of studies of Arctic eco-systems by an international team of scientists who have been collaborating during the fourth International Polar Year,which ended in 2008. Eric Post, a professor of biology at Penn State University and leader of the study team, says previous research has focused on the non-living or abiotic effects of global warming on the Arctic, including the melting of sea ice and subsequent rises in seawater levels. But Post says this is the first comprehensive report investigating the sweeping impacts of climate change on eco-systems and living creatures in the north polar region, including: "Fresh water systems, terrestrial systems, resident species, migratory species, birds, mammals, plants, pretty much everything. It seems like wherever you look in the Arctic right now, things are changing quite rapidly," he said. For example, Post says, the researchers found that red foxes and other species that thrived in the Arctic's southern ranges are moving north toward cooler, more hospitable climates. They are displacing Arctic foxes in competition for food. Other species migrating northward include winter moths that are defoliating mountain birch forests. Another biological consequence of climate change in the Arctic, according to Post, is that the plant growing season is starting earlier than it did a decade ago. "And that might sound like a benefit because it's getting warmer and greener earlier. But there are species that migrate based on light cues and are expecting to arrive on their breeding grounds in the Arctic to take advantage of resources associated with start of the growing season. But they are arriving too late now and are suffering consequences for reproduction and survival of offspring," he said. Species endangered by this earlier growing season include migratory caribou, common in the low Arctic landscape of Greenland. Increasing numbers of females there are unable to consume enough food to sustain pregnancies. Researchers did find species that benefitted from the warming temperatures, including non-migratory wild reindeer on the Norwegian archipelago. These animals take advantage of the melting snow and longer growing seasons. Scientists say reindeer populations have increased because there's more food for them to eat. The report notes that over the past 150 years, the concentration of greenhouse gases in the atmosphere has caused temperatures to warm an average of one-degree Celsius. That has resulted in a progressive loss of the Arctic's seasonal sea ice cover, at the rate of 45,000 square kilometers per year. Species that are hardest hit by the shrinking ice are polar bears, seals and walruses, all of which have experienced reductions in their populations. With temperatures expected to rise another six degrees Celsius by the end of the century, Post says polar bears, which now number between 20,000 and 25,000, face possible extinction. "Maybe within our lifetimes or the lifetime of our children, it seems like sea ice loss is happening so quickly that polar bear populations will become increasingly fragmented still. So, I think they are the ones that are at risk for extinction in the near future," he said. Post says there are still many unanswered questions about the effects of climate change in the frozen region, such as why some eco-systems are thriving while other are on the brink of collapse. Researchers hope future studies of Arctic biology will answer those questions. Their new report is published in this week's Science magazine.
Poster Comment:"The report notes that over the past 150 years, the concentration of greenhouse gases in the atmosphere has caused temperatures to warm an average of one-degree Celsius. That has resulted in a progressive loss of the Arctic's seasonal sea ice cover, at the rate of 45,000 square kilometers per year."
The issue about global warming is REAL. Some folks have dismissed the REAL issue entirely because of political flap-jaws, such as Al Gore.
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Begin Trace Mode for Comment # 12.
#1. To: buckeroo, *Agriculture-Environment* (#0)
No. People have dismissed it because the science doesn't back it up. The variations we have seen in climate are natural and constantly changing. This doom and gloom has got to go. We didn't even reach the level of medieval warm period and "nature" seemed to survive that just fine. We are already starting to cool. Couple that with the fact that despite the recent increases, CO2 is at historic lows for the planet. This is a manufactured crisis benefiting no one but the global elites.
I feel the heat rising already. Still, the average temperature of the Earth's atmosphere is rising. As a recommendation and for the future, don't buy coats .... buy bikinis to cool off! :)
Even if that were true, which it isn't, so what? As I said, we have not reached the same heat as the medieval warm period. BTW, that is also called climate optimum. Why is that? What about the Roman warm period? Warming has not been bad for this planet in the past, why should it be bad now?
Heat is bad. It is bad, bad, bad to all life and certainly humans. We live in a small bandwidth of comfort and capability to survive based upon the natural envelope given to us. The influence of modern technologies and resulting convolution about the natural environment around us, needs serious considerations ... not cheap dismissals. Show me where the Earth is actually cooling.
I've sent you an email. You need to get some better science. For someone who understands issues surrounding government propaganda you seem blind in this area.
I suspect that you don't like my comments all of a sudden. Are you attempting to bitch-slap me based upon my free and confident scientific standing certainly concerned with CO2 emissions causing spindly plants reducing the food supply?
Climate and the Carboniferous Period Average global temperatures in the Early Carboniferous Period were hot- approximately 20° C (68° F). However, cooling during the Middle Carboniferous reduced average global temperatures to about 12° C (54° F). As shown on the chart below, this is comparable to the average global temperature on Earth today! Similarly, atmospheric concentrations of carbon dioxide (CO2) in the Early Carboniferous Period were approximately 1500 ppm (parts per million), but by the Middle Carboniferous had declined to about 350 ppm -- comparable to average CO2 concentrations today!
Are you arguing that CO2 emissions make you healthy?
If you want to put it that way, yes. That's why we keep CO2 at higher levels in subs. People evolved at higher CO2 concentrations and thus really do better. The environment does better as well. Man only puts out about 3% CO2. The oceans are the big CO2 source. No amount of international regulation is going to change that.
That's why we keep CO2 at higher levels in subs. People evolved at higher CO2 concentrations and thus really do better. Wrong, and wrong. In terms of CO2 being healthy, if you're a plant that's true, as plants require CO2 for their celluar functions. We however require oxygen, not CO2. They don't ADD CO2 on subs, they use scrubbers to REMOVE it. High CO2 levels would mean the sub would have to surface as people would start keeling over otherwise. The oceans are the big CO2 source. That is misleading. Althought SOME parts of the world's oceans release CO2 (as in the tropics), MOST of the oceans ABSORB CO2. It's a cycle that keeps everything in balance, where the ocean aborbs larger amounts of CO2 than it releases, thus absorbing excess CO2 from the rest of the environment.
CO2 Capture from Air – Current Practices Jason J. Heinrich Massachusetts Institute of Technology Despite a human being’s relative tolerance to elevated CO2 levels, travel outside the breathable atmosphere, whether into space or to the bottom of the sea, requires living inside an enclosed airtight system in which carbon dioxide exhaled by the individual must be replaced by a fresh supply of breathable air. For nearly a century, researchers have been developing and testing new systems and technologies designed to remove harmful contaminants from the air and regenerate life-giving oxygen. These critical technologies have enabled humans to fly farther, dive deeper and live longer in places and conditions that do not normally support human life. This paper intends to provide a general overview of the current methods being employed to enable respiration under such circumstances.
#18. To: farmfriend (#12)
That was meant as "look, levels this high have been recorded and nobody died", it is not meant as a suggested level of operation. High CO2 levels cause headaches, nausea, difficulty in concentration, dizziness, and a host of other bad things. That is why they REMOVE CO2 from the air in subs rather than ADDING it as you implied. Did you even bother thinking about the following paragraph? Despite a human being’s relative tolerance to elevated CO2 levels, travel outside the breathable atmosphere, whether into space or to the bottom of the sea, requires living inside an enclosed airtight system in which carbon dioxide exhaled by the individual must be replaced by a fresh supply of breathable air. For nearly a century, researchers have been developing and testing new systems and technologies designed to remove harmful contaminants from the air and regenerate life-giving oxygen. These critical technologies have enabled humans to fly farther, dive deeper and live longer in places and conditions that do not normally support human life. This paper intends to provide a general overview of the current methods being employed to enable respiration under such circumstances.
In fact farmfriend, here's an authoritive source on the matter; From Emergency and Continuous Exposure Guidance Levels for Selected Submarine Contaminants (2007) SUMMARY OF TOXICITY The information below was taken largely from a more comprehensive review, Spacecraft Maximum Allowable Concentrations for Selected Airborne Contaminants, Volume 2 (NRC 1996). The studies discussed represent those most relevant to submariners and the submarine environment. CO2 is a simple asphyxiant and lethal asphyxiations have been reported at concentrations as low as 110,000 ppm (Hamilton and Hardy 1974). Loss of consciousness can occur within a minute of exposure at 300,000 ppm and within 5- 10 minutes (min) of exposure at 100,000 ppm (HSDB 2004). The effects of concentrations of CO2 between 7,000 and 300,000 ppm in humans and animals are discussed below and include tremor, headaches, chest pain, respiratory and cardiovascular effects, and visual and other central nervous system (CNS) effects. The respiratory, cardiovascular, and CNS effects of CO2 are related to the decreases in blood and tissue pH that result from exposures (Eckenhoff and Longnecker 1995; Yang et al. 1997; HSDB 2004). Changes in pH act directly and indirectly on those systems. The pH changes also trigger various compensatory mechanisms, including increased ventilation to reduce excess CO2 in the bloodstream, increased renal acid excretion to restore acid-base balance, and sympathetic nervous system stimulation to counteract the direct effects of pH changes on heart contractility and vasodilation (Eckenhoff and Longnecker 1995; HSDB 2004). The key effects for setting EEGL and CEGL values are tremor, headache, hyperventilation, visual impairment, and CNS impairment. Effects in Humans Accidental Exposures In a case report of two men who lost consciousness in a wellhead chamber as a result of exposure to a “high concentration” of CO2 in the atmosphere, one man exhibited constricted visual fields, enlarged blind spots, photophobia, loss of convergence and accommodation, deficient dark adaptation, headaches, insomnia, and personality changes (Freedman and Sevel 1966). The other man died of asphyxia. In a similar incident, one overexposed man died after 11 months in a coma; he exhibited retinal atrophy and gliosis as well as loss of all ganglion cells (Sevel and Freedman 1967). In addition to that delayed fatality, three men died immediately from asphyxia. These studies are not relevant to establishing EEGL and CEGL values, but they are consistent with the findings that CO2 affects vision.
Top • Page Up • Full Thread • Page Down • Bottom/LatestThe issue about global warming is REAL. Some folks have dismissed the REAL issue entirely because of political flap-jaws, such as Al Gore.
#2. To: farmfriend (#1)
#3. To: buckeroo (#2)
Still, the average temperature of the Earth's atmosphere is rising.
#4. To: farmfriend (#3)
#5. To: buckeroo (#4)
#6. To: farmfriend (#5)
I've sent you an email. You need to get some better science. For someone who understands issues surrounding government propaganda you seem blind in this area.
#7. To: buckeroo, vitamin Z, *Agriculture-Environment* (#6)
Similarities with our Present World
#8. To: farmfriend (#7)
#9. To: buckeroo (#8)
(Edited)
Are you arguing that CO2 emissions make you healthy?
#11. To: farmfriend, buckeroo (#9)
#12. To: FormerLurker, buckeroo (#11)
June 2003
MIT LFEE 2003-001 WP
Laboratory for Energy and the Environment
77 Massachusetts Avenue
Cambridge, MA 02139-4307 http://lfee.mit.edu/publications/ Publication No. LFEE 2003-001 WP INTRODUCTION
People generate carbon dioxide at a rate of about 1 kg/person/day (2.2 lbs/person/day). In confined spaces, this can lead to elevated levels of CO2. These CO2 concentrations above normal levels do not necessarily produce harmful working conditions. OSHA guidelines allow workers to operate in a CO2 air contaminant limit of 5,000 ppm1 for more than 8 hours. Submarines often operate at levels close to 7,000 ppm and have even recorded levels of 30,000 ppm (Honeywell 1989). The air revitalization system on the first international space station, Freedom, was designed to maintain CO2 levels of 2000 ppm or less, while life support systems designed for space suits maintain CO2 levels at or below 5000 ppm.
Replies to Comment # 12. Submarines often operate at levels close to 7,000 ppm and have even recorded levels of 30,000 ppm (Honeywell 1989).
#19. To: farmfriend, buckaroo, clitoria (#12)
Submarine crew are reported to be the major source of CO2 on board submarines (Crawl 2003). Data collected on nine nuclear-powered ballistic missile submarines indicate an average CO2 concentration of 3,500 ppm with a range of 0- 10,600 ppm, and data collected on 10 nuclear-powered attack submarines indicate an average CO2 concentration of 4,100 ppm with a range of 300-11,300 ppm (Hagar 2003).
End Trace Mode for Comment # 12.