This is precisely my point. There is a strong and growing body of evidence that overwhelmingly suggests human activities are driving global warming. Because of the statistical nature of climate data and predictions, we cannot be 100% certain of the projected outcomes (compared with a scientific theory like evolution, which is now absolutely incontrovertible). I have faith in the scientific process that if the hypothesis of anthropogenic global warming is incorrect, it will be proven as such. This has not occurred. There is extreme concurrence among scientists that warming is occurring and is being driven by human activities.
After watching that video, there is literally no credible challenge to climate theory mentioned in it.
1. Thermometers claim -absolute bullshit. Climatologists rely on multiple proxy thermometers.
2. Water vapor claim- water vapor is a global warming gas. However, its concentration is a function of global temperature, not a driver of it.
3. Paved roads and deforestation- People do talk about these things and they are already included in models.
4. Plants grow faster- This is true at first, however the limiting nutrient in most ecosystems is not CO2 (usually its nitrogen). Plants will grow faster in response to higher CO2, untill they reach their limiting nutrient, at which point growth can actually be slower than before the CO2 increase due to altered nutrient cycling.
5. The rest seems to be a rambling misrepresentation of basic climate science and the predicted results from climate change.
I really don't care either way about the whether humans are or are not causing climate change;
my issue with the way this discussion occurs all the time in popular media is that it is an affront to science and the scientific process: the pro and con arguments for anthropogenic climate change are not equal and should not be given equivalent credence.
The evidence currently suggests that climate change is occuring, and the chance that it is not is vanishingly small, and increasingly so. However, the pessimist about humans that I am, It doesn't matter; our species will almost certainly (1) fail to perceive the issue (2) perceive the issue, but fail to act (3) perceive the issue, but act in the wrong ways.
The most probable end result is that climate change will be driven (regardless of scenario 1 th rough 3) to its most severe or nearly most severe possibility. This is especially true because there will be winners and losers in climate change (the only tangential point made in that video that actually holds some water). If you live in a cold region which will experience increased temperatures and rainfall that increases (within reason) you may benefit by experiencing longer growing seasons and more rapid plant growth. People in these regions seem to have no benefit in slowing this potential windfall.
Also, as an environmentalist, I lament that climate change takes so many resources away from other issues which have higher prospects of successful action (like reducing chemical and heavy metal pollutants, and managing forest resources sustainably).
For these reasons I think we should be focusing on adapting to the coming (inevitable) climate change (more along the lines of Bjorn Lomborg (though I should add he is much more optomistic than I am, out of what I see as his ignorance of ecology and biology). The more interesting questions to me are where ecosystems will move, where habitable regions will be, and those types of things. I am especially interested in the prospect of human assisted ecosystem and species migrations and their climate range shifts as natural corridors (which would allow natural migration) are now blocked by humans (roads, barriers, etc). However the pessimist in me also reminds me that for civilization as we know it to actually survive, we would also have to relocate entire nations of people. So the realistic outcome is genocide, war, starvation, and mass migration.
I do have a pet, take a lot of flights, own a car, and eat some meat (after many years as a vegetarian). Largely it is because I have given up on the prospect that humans will act sufficiently and I am not going to be a personal martyr for a lost cause. Our world is now sadly a human garden, and little else. It could even be possible to argue as an ultimate pessimist that we should do all we can to accelerate global warming so that the reckoning comes sooner and therefore (assuming continued population growth) less human beings will be alive to experience its negative effects.