or do you believe in the great global warming scandel and think the world is heating up due to a natural cycle?
opinions please!
We know it%26#039;s warming, and we%26#039;ve measured how much:
http://www.epa.gov/climatechange/science...
Scientists have a good idea how the Sun and the Earth%26#039;s natural cycles and volcanoes and all those natural effects change the global climate, so they%26#039;ve gone back and checked to see if they could be responsible for the current global warming. What they found is:
Over the past 30 years, all solar effects on the global climate have been in the direction of (slight) cooling, not warming. This is during a very rapid period of global warming.
http://news.bbc.co.uk/2/hi/uk_news/62902...
http://www.pubs.royalsoc.ac.uk/media/pro...
A recent study concluded:
“the range of [Northern Hemisphere]-temperature reconstructions and natural forcing histories…constrain the natural contribution to 20th century warming to be %26lt;0.2°C [less than one-third of the total warming]. Anthropogenic forcing must account for the difference between a small natural temperature signal and the observed warming in the late 20th century.”
http://www.pnas.org/cgi/content/full/104...
You can see this in the third graph here, where the dotted lines are just from natural causes, and the full lines are natural + human causes:
http://www.pnas.org/content/vol104/issue...
If that’s not enough to convince you the Sun isn’t responsible, consider the fact that no scientific study has ever attributed more than one-third of the warming over the past 30 years to the Sun, and most attribute just 0-10% to the Sun.
http://answers.yahoo.com/question/index;...
So the Sun certainly isn%26#039;t a large factor in the current warming. They%26#039;ve also looked at natural cycles, and found that we should be in the middle of a cooling period right now.
%26quot;An often-cited 1980 study by Imbrie and Imbrie determined that %26#039;Ignoring anthropogenic and other possible sources of variation acting at frequencies higher than one cycle per 19,000 years, this model predicts that the long-term cooling trend which began some 6,000 years ago will continue for the next 23,000 years.%26#039;%26quot;
http://en.wikipedia.org/wiki/Milankovitc...
http://www.sciencemag.org/cgi/content/ab...
So it%26#039;s definitely not the Earth%26#039;s natural cycles. They looked at volcanoes, and found that
a) volcanoes cause more global cooling than warming, because the particles they emit block sunlight
b) humans emit over 150 times more CO2 than volcanoes annually
http://volcano.und.edu/vwdocs/Gases/man....
So it%26#039;s certainly not due to volcanoes. Then they looked at human greenhouse gas emissions. We know how much atmospheric CO2 concentrations have increased over the past 50 years:
http://en.wikipedia.org/wiki/Image:Mauna...
And we know from isotope ratios that this increase is due entirely to human emissions from burning fossil fuels. We know how much of a greenhouse effect these gases like carbon dioxide have, and the increase we%26#039;ve seen is enough to have caused almost all of the warming we%26#039;ve seen over the past 30 years (about 80-90%). You can see a model of the various factors over the past century here:
http://en.wikipedia.org/wiki/Image:Clima...
This is enough evidence to convince almost all climate scientists that humans are the primary cause of the current global warming. 40% 4 Votes
and have you watched this?
http://www.youtube.com/watch?v=bDsIFspVz... http://news.nationalgeographic.com/news/...
http://www.worldpublicopinion.org/pipa/a...
http://www.worldviewofglobalwarming.org/... 0% 0 Votes
The Earth%26#039;s cycles don%26#039;t take billions of years. The cycles can occur within the time frame of tens of thousands of years, with mini-warming and cooling phases in between.
And when you consider that the energy that warms the Earth comes ENTIRELY from the Sun, how is it possible to say that the Sun contributes less than 10% of the causes of any warming that occurs on the Earth? Ludicrous.
The Earth has been undergoing climate change since it developed an atmosphere in it%26#039;s early formation, and after it%26#039;s crust hardened and cooled enough for the oceans to form.
When you look at the size and scale and complexity of the Earth and the tremendous heat exchange properties between the oceans and atmosphere and land masses, mankind%26#039;s efforts are reduced to mere nuisances.
When one major volcanic eruption can emit more greenhouse and toxic gases than all the pollution released by mankind from the beginning of the industrial revolution to present, the contributions of mankind%26#039;s living seem rather puny. The one thing man could do to upset the Earth%26#039;s balance would be a massive nuclear war, and we can only hope and pray that such a thing would never happen.
The warming period after that last major ice-age occurred long, long before there were any SUV%26#039;s or industrial pollution. What caused this to happen? Massive Mastodon flatulation? Mammoth methane? I%26#039;d be willing to go out on a limb and say it was the Sun and possibly a minor change in the Earth%26#039;s tilt and rotation.
Why worry about something that nobody has any control over? And who can say that the climate we have right now is the optimum condition of the Earth? I don%26#039;t think anybody alive today has been around long enough to describe anything better.
But this is a matter you have to decide for yourself. Are you going to be calm and accept things as they are or are you going to become one of the %26quot;chicken-littles%26quot; of the world, hanging onto Al Gore%26#039;s coattails as he preaches doom and gloom and %26quot;why don%26#039;t you buy some of my carbon credits to save the world?%26quot;
Now, you%26#039;ll have to excuse me while I go out and fire up my charcoal burning grill and char some beef ... 0% 0 Votes
I definitely believe that it has a lot to do with human beings and the burning of fossil fuels. 10% 1 Vote
ice age - theory/myth
no actual proof of ice ages 0% 0 Votes