G'day,
Polar Bears. This is a difficult subject because every single polar bear is not tagged. The WWF says that polar bears are not endangered, their numbers are stable or increasing. Others say differently. If you really wanted to argue about polar bears you would have to know how they are being counted now and have been counted in the past. There is a real possibility that previous counts double counted bears or that they were based on an estimate or indirect evidence. But it could also be that the 1,194 polar bears that are being observed by the Canadian Wildlife Service have been reduced to 935. How? By poaching perhaps. By shooting because they intruded on civilisation. How about they decided they didn't like being Canadian and have decided to wander into the US instead? Does that change in number prove global warming? This is the trouble with using abstract information to suggest global warming. Too many possible unrelated causes.
So let's not be so abstract. Lets look at the average temperature anomolies for the arctic regions. According to the satellite data there has been some regional warming and some regional cooling and overall, nothing. No difference in 30 years. So if the bears are dying it is really difficult to say it is global warming when overall their region has not changed in temperature.
And in the case of polar bears we even have conflicts as to what is happening with their population. If there are more of them where it is getting regionally warmer could that mean that they are migrating or having more cubs in response to some environmental trigger? How would I know? Unless you are a polar bear expert, how would you?
The crack about the four dead polar bears comes from An Inconvenient Truth. Mr Gore says that for the first time significant numbers of polar bears are drowning. He is referring to a study that records the observation of four dead polar bears after a major wind storm. I do not believe the two match all that well.
Mike, I've watched "An Inconvenient Truth" and commented on it at length on this forum before. It is very well presented but the science behind it goes from marginal to just plain wrong. Even though most scientists, even those that strongly agree with Global Warming, have agreed that the Mann graph is deceptive and based on invalid scientific method, Mr Gore continues to use it as if it is the unvarnished truth. Bit like the polar bears. Goes on about tropical glaciers when the majority of the melt of these glaciers occurred more than a century ago, well before supposed man-made global warming. The speed of melting of these glaciers has actually slowed in recent years.
I've already mentioned Mr Thompson's analysis of ice cores a few times but its worth mentioning again. You do not get six wildely differing results from six cores in three glaciers and decide that the way to resolve the differences is to average the results. Four of the cores did not support Mr Thompson's theories at all (the majority) but the two that did did so to a larger extent than the other four. Thus the average presents a result that only two of the six cores agrees with. I cannot see how anyone interested in accurate science can say this is good science or valid, yet this study is often quoted, including extensively by Mr Gore.
Mike, I'm happy to discuss any particular subject brought up by Mr Gore. His slide presentation is not science. He is an evangalist on global warming, that much is clear. He is also extremely good at putting his point across but none of the science is his. A great deal of what he has said in the Inconvenient Truth has annoyed even those that overall agree with him. The Mann "hockey stick" for instance does not go down well with those that have to face further discussion about something that has previously been settled.
Regards
Richard
