Unfortunately, I read that textbook a while ago.
Again, I said basically. There are some exceptions, and there will never be true complete consensus. But when over 90% of scientists believe that this is a human-caused issue, it becomes clear that there is a general scientific belief.
Fair enough. My point is that sceptics in science need not be unfairly characterized as pseudoscientists. There are many who refer to themselves as AGW "agnostics" - they understand the hypothesis but want to see more evidence. The concern is that such derogatory descriptives silence valuable debate that is essential to clarification. That being said, thanks for the links.
In most climate models for the future in a global warming scenario, Antarctica is actually experiencing considerably less heating than the rest of the earth. I'm not an expert, but I do believe that this is because of the influence of the Southern Ocean and it's relative isolation from the rest of the global ocean in terms of warm water currents. There is also the fact that there is currently a very thick ice sheet on top of Antarctica which covers a huge amount of land, reflecting lots of solar radiation while the arctic has a much bigger freeze/melt cycle which gives far more ground and ocean to absorb sunlight.
Though Antarctic ice isn't exactly "stable." The disaster of the Larsen B ice shelf is proof enough of that, and glaciers in Antarctica are almost universally diminishing at a faster pace than before.
Regarding the Larsen B ice shelf, it's important to note that complex sediment and petrographic studies indicate that this shelf reformed during the Little Ice Age period. There is a large body of data that indicates the greatest extent of the Larsen ice shelves during the Holocene likely occurred only a few hundred years ago, and that the portions of that have shown some disintegration likely were created during the LIA. Additionally, it would appear that about 2,000 years ago, both the Larsen A and B ice shelves were almost completely absent, and that Antarctic temperatures of that time were likely much warmer than today.
Pudsey, C.J., et al. 2006.
Ice shelf history from petrographic and foraminiferal evidence, Northeast Antarctic Peninsula. Quaternary Science Reviews 25: 2357-2379.
Hemer, M.A., Harris, P.T. 2003.
Sediment core from beneath the Amery Ice Shelf, East Antarctica, suggests mid-Holocene ice-shelf retreat. Geology 31: 127-130.
In the entire history of the earth, counting this entire glacial period that we've been in for the past several million years, then yes. But as a trend among the relatively stable climate of glacial maximums and minimums we've been having, it's a huge change, and it's quite surprising and should be seen as a big danger when millions of years of stability is broken down back to temperatures that are reminiscent of megafauna that existed hundreds of millions of years ago.
Against the larger backdrop of the entire glacial period history, an interglacial period may
appear to be stable, but over the million year duration of the ice age, the warmer interglacial events can, themselves, be viewed as recurring perturbations within a much colder climate history. With respect to the Holocene, there have been many climatic variations over the course of the last 10,000 years - many of which have greatly exceeded the variations that have occurred over the past 150 years. Virtually all of these significant climatic changes occurred long before the development of modern civilization and are the result of natural events. Based on this history, it should be expected that there will be more erratic climatic behavior in the future that is not caused by human beings.
Overpeck, J., Webb, R. 2000.
Nonglacial rapid climate events: Past and future. Proceedings of the National Academy of Sciences USA 97: 1335-1338.
Again, more research is necessary in order to clearly delineate the scale or degree of a human impact on climate from natural variations that are ongoing.
Perhaps there does need to be more evidence in support of AGW, if only to absolutely convince scientists and members of the public that global warming is mainly due to human practices and therefore a preventable thing.
With respect to more research, no disagreement here. At the same time, there must be an effort to take a very clear look at the very strong potential for natural causes, or a combination of both human and natural activities. Climate variation over time is a well established fact. What needs to be better understood is the past 150 years
within that context. Again, that is not a refutation of AGW.
But already, there're mounds of data showing correlations between human activity and Global Warming and rising GHG trends. I'm always quite disappointed when people decide that we need more information to be sure before we act on anything.
As noted, more research gets the benefit of either better understanding the degree of a human impact (and personally I think the question for exploration is the
degree of impact: small or large. The position of "no impact at all" is likely incorrect). It is very necessary to acquire a better comprehension the complex workings of the natural global climate system in order for any such measure of degree to be understood. There is good evidence to suggest that there are natural climate forcings in play as well.
Regarding action, given the ever greater demand for oil in both the developing and developed nations, and the increasing economic, environmental and political costs associated with recovery, exploration and future deep sea drilling for new sources, there is already a good reason for looking at alternatives. Even if the AGW hypothesis was refuted tomorrow, these things wouldn't change.
Ah well, HOW BOUT 9/11? Kamuix, I'd like to see your response to my points on the last page.
You know what Kamuix would say: narrow minded, brainwashed dupes of the whomever and whatever.