So enough of this denialism bullshit. If you're not a trained climatologist, I couldn't give a flying fuck at the end of a gun why you think the scientific consensus is wrong. As for Joe Blow denialist off the street-he has nothing at his disposal but a bunch of poorly understood, faith based, cherry picked arguments absorbed from the mouth of his favorite talk radio host. In short, he has the free-will of a termite.
So what do the vast majority of experts *actually* believe the deal is with AGW? Here's their main arguments and refutations with references if you care to learn about them:
(and refreshingly, Al Gore has absolutely nothing to do with any of this)
Scientific studies have shown that the current warming is not natural.
There are many basic scientific facts which can only be explained if the current global warming is being caused by an increased greenhouse effect due to carbon dioxide accumulating in the atmosphere from humans burning fossil fuels. For example, the planet is warming as much or more during the night than day. If the warming were due to the Sun, the planet should warm a lot more during the day when the Sun has influence. Greenhouse gases trap heat all the time, so they warm the planet regardless of time of day. Another example is that the upper atmosphere is cooling because the greenhouse gases trap the heat in the lower atmosphere. If warming were due to the Sun, it would be warming all layers of the atmosphere.
We know it's warming, and we've measured how much.
Scientists have a good idea how the Sun and the Earth's natural cycles and volcanoes and all those natural effects change the global climate, so they'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. (2) (3)
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 <0.2°c>
You can see this in the third graph here (5), where the dotted lines are just from natural causes, and the full lines are natural + human causes.
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. So the Sun certainly isn't a large factor in the current warming. They've also looked at natural cycles, and found that we should be in the middle of a cooling period right now."An often-cited 1980 study by Imbrie and Imbrie determined that '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(6)
So it's definitely not the Earth'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 So it's certainly not due to volcanoes.(7) Then they looked at human greenhouse gas emissions. We know how much atmospheric CO2 concentrations have increased over the past 50 years (8)
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've seen is enough to have caused almost all of the warming we've seen over the past 30 years (about 80-90%). You can see a model of the various factors over the past century at the bottom of the page(9). The correlation with CO2 modeled temp is ridiculously close.
This is enough evidence to convince almost all climate scientists that humans are the primary cause of the current global warming.
If you think they're wrong you'd better have a good fucking reason. Because if their right, the denialist is a major part of the problem.