Showing posts with label animals affected by global warming. Show all posts
Showing posts with label animals affected by global warming. Show all posts

Monday, August 30, 2010

İs Weather Extremities might be another case of Global Warming?

The recent spate of disasters in far-flung areas – successive floods in New England, Nashville, Arkansas, and Oklahoma; and a torrent in Pakistan – have, once again, revived the much-debated-about issue pertaining to the effect of global warming in causing extreme weather conditions.

The extremities of weather have become evident from the fact that while the floods toppled the lives of more than 20 million people; the summer heat in the eastern US, parts of Africa and eastern Asia, as well as Russia, led to the loss of millions of acres of wheat and thousands of lives in the worst-ever drought in history.
With such extreme weather conditions being clearly disquieting, the scientific community more or less is collective in expressing the opinion that global warming “probably” is taking its toll on the weather round the world.
Noting that “the climate is changing,” Jay Lawrimore – the climate analysis head at the National Climatic Data Center in Asheville, N. C. – said: “Extreme events are occurring with greater frequency and, in many cases, with greater intensity.”
Lawrimore further added that the excessive heat, in particular, is apparently “consistent with our understanding of how the climate responds to increasing greenhouse gases.” Scientists believe that the theory about greenhouse gases underscores more weather extremes in the future – like heavier rainstorms in summer, bigger snowstorms in winter, and more intense droughts due to more record-breaking heat waves – most of which, as per reports, are already being experienced!

Wednesday, August 18, 2010

Victim of global warming? Scientists believe it may actually have been climate change that killed the mammoth off

Did global warming kill off the woolly mammoth? Scientists say it may have been climate change that wiped out the beasts

Human have always taken the blame for wiping out the woolly mammoth.
But although man hunted the beasts for their skin and meat, scientists believe it may actually be climate change that killed the mammoth off.
Some 21,000 years ago, after the last Ice Age, warmer temperatures led to a loss of grassland over much of the Earth’s surface.

As the prairies and steppes dwindled, spreading forests took their place. These changes made survival impossible for the big, grazing herbivores and the predators that fed on them, according to a Durham University study, the most comprehensive of his kind.
Researcher Professor Brian Huntley said: ‘Woolly mammoths retreated to northern Siberia 14,000 years ago, whereas they had roamed and munched their way across many parts of Europe, including the UK, for most of the previous 100,000 years.
'It would have been difficult for man to  wipe them out because our species was not so widespread then and did not have the technology.
‘We know from mammoth fossils that they were hunted by humans. But they would not have been an  easy kill because of their size.’
His research on the climate firmly points the finger at rising temperatures.
The woolly rhino, cave lion, giant deer and cave bear also failed to survive the new conditions.
Although some small pockets may have clung on, their fate had effectively been sealed.
‘Mega-mammals found it increasingly difficult to find food,’ said Dr Huntley. ‘We believe the  loss of food supplies from productive grasslands was the major
contributing factor to extinction.’
The Durham experts, who worked with researchers from London’s Natural History
Museum, report their findings in the journal Quaternary Science Reviews.
And they say we should learn the lessons of the past.
‘This is a model for what may happen as a result of rapid climate change over the next century,’ said Dr Huntley.
Big species today, such as the elephant, are likely to be among the first affected by climate change, he added.

 

Tuesday, August 17, 2010

What is GreenHouse Effect ?

The greenhouse effect is a process by which radiative energy leaving a planetary surface is absorbed by some atmospheric gases, called greenhouse gases. They transfer this energy to other components of the atmosphere, and it is re-radiated in all directions, including back down towards the surface. This transfers energy to the surface and lower atmosphere, so the temperature there is higher than it would be if direct heating by solar radiation were the only warming mechanism .

This mechanism is fundamentally different from that of an actual greenhouse, which works by isolating warm air inside the structure so that heat is not lost by convection.

The greenhouse effect was discovered by Joseph Fourier in 1824, first reliably experimented on by John Tyndall in 1858, and first reported quantitatively by Svante Arrhenius in 1896.

If an ideal thermally conductive blackbody was the same distance from the Sun as the Earth, it would have an expected blackbody temperature of 5.3 °C. However, since the Earth reflects about 30%[4] (or 28%) of the incoming sunlight, the planet's actual blackbody temperature is about -18 or -19 °C , about 33°C below the actual surface temperature of about 14 °C or 15 °C. The mechanism that produces this difference between the actual temperature and the blackbody temperature is due to the atmosphere and is known as the greenhouse effect.

Global warming, a recent warming of the Earth's surface and lower atmosphere, is believed to be the result of a strengthening of the greenhouse effect mostly due to human-produced increases in atmospheric greenhouse gases.
Source : Wikipedia

Sunday, August 15, 2010

Saturday, August 14, 2010

How is Wildlife Affected by Global Warming?

Most researchers agree that even small changes in temperature are enough to send hundreds if not thousands of already struggling species into extinction unless we can stem the tide of global warming. And time may be of the essence: A 2003 study published in the journal Nature concluded that 80 percent of some 1,500 wildlife species sampled are already showing signs of stress from climate change.
How Global warming Affects Wildlife
The key impact of global warming on wildlife is habitat displacement, whereby ecosystems that animals have spent millions of years adapting to shift quickly. Ice giving way to water in polar bear habitat is just one example of this.
Another, according to The Washington Post, is the possibility that warmer spring temperatures could dry up critical breeding habitat for waterfowl in the prairie pothole region, a stretch of land between northern Iowa and central Alberta.
Affected wildlife populations can sometimes move into new spaces and continue to thrive. But concurrent human population growth means that many land areas that might be suitable for such “refugee wildlife” are already taken and cluttered with residential and industrial development. A recent report by the Pew Center for Global Climate Change suggests creating “transitional habitats” or “corridors” that help migrating species by linking natural areas that are otherwise separated by human settlement.
Shifting Life Cycles and Global warming
Beyond habitat displacement, many scientists agree that global warming is causing a shift in the timing of various natural cyclical events in the lives of animals. Many birds have altered the timing of long-held migratory and reproductive routines to better sync up with a warming climate. And some hibernating animals are ending their slumbers earlier each year, perhaps due to warmer spring temperatures.
To make matters worse, recent research contradicts the long-held hypothesis that different species coexisting in a particular ecosystem respond to global warming as a single entity. Instead, different species sharing like habitat are responding in dissimilar ways, tearing apart ecological communities millennia in the making.
Global warming Effects on Animals Affect People Too
And as wildlife species go their separate ways, humans can also feel the impact. A World Wildlife Fund study found that a northern exodus from the United States to Canada by some types of warblers led to a spread of mountain pine beetles that destroy economically productive balsam fir trees. Similarly, a northward migration of caterpillars in the Netherlands has eroded some forests there.
Which Animals Are Hardest Hit by Global warming?
According to Defenders of Wildlife, some of the wildlife species hardest hit so far by global warming include caribou (reindeer), arctic foxes, toads, polar bears, penguins, gray wolves, tree swallows, painted turtles and salmon. The group fears that unless we take decisive steps to reverse global warming, more and more species will join the list of wildlife populations pushed to the brink of extinction by a changing climate.

The Original Post:
http://environment.about.com/od/globalwarming/a/global_warm_wil.htm