All I can say is, I hope they finally make some good decisions in Copenhagen in December.
> 110,000 years ago global sea level was (about) 2-3m higher than the present. At the time global temperatures where at the peak for the last interglacial and very similar to the present time (which are now above the early peak for the current interglacial). The best proxies I've seen for this are ocean cores which show that areas such as the warm pool are now warmer the warmest in 110,000 years. You can't use long ice cores from places such as Vostok as these have a delay of around 100 years so still haven't registered human caused warming (owing to the very low rate of snow accumulation).
> The extra sea level came about 50% from Greenland which had a much smaller ice sheet, and the West Antarctic Ice sheet which was a little smaller than the present. The reason why this period was slightly warmer that the current integlacial (prior to human's super charging the greenhouse effec) was owing to greater solar insolation in northern high latitudes during their summer.
> This short history lesson tells us that only the slightest of temperature rises (certainly no more than 2C) will raise sea level by 2-3m. This is hardly surprising as Greenland gets near 0C over much of the ice sheet in summer and has quite a low gradient around much of its margins. Warm it up a little and you set in place a feedback where it melts, the surface lowers (and so gets warmer) it melts more etc. Surging of outlet glaciers also come into play. You can see a similar effect happening across the Tasman Sea ATM where the Tasman glacier is disintegrating - the warming of around 1C has now see the surface melt down around 200m in places which means the glaciers surface is now witnessing the equivalent of around 3C of warming. That glacier will eventually melt back to be a tiny fraction of what it once was.
> When you warm the planet by more than 2C you will start to loose parts of the Antarctic - this ice sheet is only a few million years old (the very oldest ice is around 30 million years in isolated pockets) - it has only been in the last 1-2 millions years that the planet has been cold enough to support this large ice sheet. That is worth 70m of extra sea level.
> Those who watched channel 9 news this week will have seen Ian Plimer remarking about prior large sea level changes as some reason why we don't need to care about current changes. Of course - this is false logic. History tells us that slight temperature changes have big effects. Sadly the journo - like most - didn't have the understanding of the material to draw attention to this false logic....
> DJ
> ________________________________________
> From: austpacwx@googlegroups.com [austpacwx@googlegroups.com] On Behalf Of Michael King [mski...@yahoo.com.au]
> Sent: Saturday, 31 October 2009 5:40 AM
> To: austpacwx@googlegroups.com
> Subject: [austpacwx] Re: Political weather catastrophes
> I wouldn't be too worried about the 'glaziers' on Greenland. Althought they can be a real 'pane', and they are prime suspects, they have 'framed' in the past, but most times, you can usually see through what they are up to! : )
> ________________________________
> From: Marcus <mawint...@gmail.com>
> To: austpacwx@googlegroups.com
> Sent: Fri, 30 October, 2009 10:55:56 PM
> Subject: [austpacwx] Re: Political weather catastrophes
> Hi Bussy,
> I think the main concern is the glaziers on Greenland; and please people correct me if I’m wrong, but once the polar Ice shelf is gone we will see rapid temp rises in that region causing the glaziers to melt in turn a sharp sea rise.
> Interesting little line of storms moving across Melbourne Now
> From: austpacwx@googlegroups.com [mailto:austpacwx@googlegroups.com] On Behalf Of Bussy
> Sent: Friday, 30 October 2009 9:51 PM
> To: austpacwx@googlegroups.com
> Subject: [austpacwx] Re: Political weather catastrophes
> Call me stupid but where the hell is all this added water gunna come from?
> 8/9ths of icebergs are under water. Ice takes up more space than water. So, realistically, if all the ice melts then there will be arguably no rise in the water level. And mathematically a drop in the level. An 8th taking up more space (as ice does) and then melting equates to less water than the area it is taking up. So with that equation, sea levels should drop when the ice melts and therefore takes up less space than in its frozen state.
> Okay we have snow and ice on our higher mountains etc.
> Same sort of deal. Not sure but a metre of snow that melts makes 100mm of water. Stand corrected there. Our planet is not overly covered with snow and ice on the continents if it did all melt. Not including sea ice etc as I mentioned before.
> So if everything melts, where the hell are we gunna get massive sea rises?
> Feel sorry for the polar bears etc which rely on the ice but that's another story.
> Where is all this added water gunna come from to make the sea rise so much that its gunna in-undate us with floods etc.
> I'm dumb.
> Bussy
> ----- Original Message -----
> From: Lindsay Smail<mailto:g...@pipeline.com.au>
> To: austpacwx@googlegroups.com<mailto:austpacwx@googlegroups.com>
> Sent: Friday, October 30, 2009 8:08 PM
> Subject: [austpacwx] Re: Political weather catastrophes
> Hi Clyve and all - You are not on your own Clyve. I think we have to continually keep abreast of the science (and the politics) to be properly informed. As for those who don't think for themselves and blindly follow what they are told without checking it out, well, I'm afraid human nature is a very difficult thing to change voluntarily. Lindsay
> ----- Original Message -----
> From: Clyve Herbert<mailto:mes...@iprimus.com.au>
> To: austpacwx@googlegroups.com<mailto:austpacwx@googlegroups.com>
> Sent: Friday, October 30, 2009 1:05 PM
> Subject: [austpacwx] Political weather catastrophes
> Hi all.
> I was puzzle last week when the media started pushing coastal inundation and up to 20% of coastal Tasmania will be washed away by 2100 (that's the year not the time). Then the news started reporting all coastal areas of Australia are under threat and anybody living within 80 to 100M of the coast will be washed to oblivion. So this week a two day barrage from the federal Government over carbon tax and the trillions of dollars to be made (by someone) all relating to the massive sea level rises expected and all on the back of a weeks worth of media hype. Sorry everybody but I find the whole process misleading and dangerous. So far this year we have been frightened by catastrophic fires expected this summer and now catastrophic flooding expected in the next 20 to 50 years along our coasts, the whole climate debate has got itself into 'Absolutely ' believing in what the computers are telling us. Shame Shame Shame....best regards Clyve Herbert
> <BR<BR
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