So says the BBC. It's worth noting that several accredited reviewers of the IPCC, including David Wasdell, claim that such would almost certainly set in motion potentially irreversible release of sequestered methane clathrates. This might be important when you consider that at least one of the two worst extinction events in the planet's history (maxing out at somewhere around 98% of all life on earth) were caused by irreversible release of sequestered methane clathrates leading to runaway global warming, poisoning of the oceans etc.

So says the BBC. It's worth noting that several accredited reviewers of the IPCC, including David Wasdell, claim that such would almost certainly set in motion potentially irreversible release of sequestered methane clathrates. This might be important when you consider that at least one of the two worst extinction events in the planet's history (maxing out at somewhere around 98% of all life on earth) were caused by irreversible release of sequestered methane clathrates leading to runaway global warming, poisoning of the oceans etc.

We are thinking of buying a house in Leeds for the grandkids to inherit, by the time they are grown up it will be overlooking the sea

Its why I live on top of the highest point in Leeds

I'll be one of the last around here to get his feet wet, however if the water tower goes at the very top of this hill then I'm royally fooked.

I agree we need to curb our appetite for things that will harm the earth, but is there not some mileage in the notion that the earth goes through natural peaks and troughs, temperature-wise.

For instance, the fact we've had ice ages tells me that the earth gets cold sometimes, and I'm sure man-made greenhouse gases had nothing to do with that. Are we not just in an 'upward' cycle?

Climate change aside, I definitely support the reduction in the use of fossil fuels, and cutting down on waste. It's a central theme to my company and the changes we have to make are indeed very small and hardly noticable, and even habit forming when you get into a routine. It also has a very nice side effect of costing us less money!

The earth's climate does re-adjust because of occasional orbital wobbles and solar output. But these changes tend to occur over glacial time-scales.

The key factor here is carbon dioxide, which we know is a greenhouse gas. We have extensive records of atmospheric carbon dioxide stretching back hundreds of millions of years. So far we have found little evidence of such a massive injection of carbon dioxide in such a small amount of time (two hundred years, max). We really are in unprecedented territory here.

The big worry is temperature rise sufficient to release stored methane deposits which tot up to twice the total amount of all hydrocarbon deposits (oil, gas, coal etc.) put together.

Methane is twenty times more effective than carbon dioxide as a greenhouse gas.

What's more, the release of this methane may well set in motion a feedback loop as methane release is directly proportional to temperature rise.

Fair enough, Mugwump. I get all that.

However, whilst I'm not ridiculing the theory behind all this, there is one thing I can't get my head around, genuinely, and that's rising sea levels due to melting glaciers and icebergs.

80% of an iceberg is reportedly underwater, and given that water reduces in size when it melts, then I don't get how sea levels can rise. Similarly, higher general temperatures should create more water vapour in the air. Seeing as no 'new' water is ever created (it is effectively recycled through vapourisation and subsequent rainfall), surely this water vapour will come from the sea, rivers, etc.

If I am wrong, then I will of course hold my hands up.

Icebergs are just little bits of glacier bobbing about in the sea. The issue is the glaciers melting - the icebergs are a symptom rather than a cause. The sheer volume of the Earth's water locked up in glaciers and in permafrost is enormous, and this water is not currently in either the oceans or rivers - hence the rise in sea level if/when it melts.

Losing glaciers also has another effect on global temperatures. Glaciers are, by and large, highly reflective and serve to reflect some of the Sun's heat back out into space (the albedo effect). As they melt, more and more of the Sun's heat is absorbed rather than reflected.

If the human race had never happened, the earth would still be going through its current phase of warming up, it did it before we were here and it will do it long after we are gone.

The glaciers are on land, not in the sea. So if they do melt, they'll add to the sea water level.

To reinforce what's been said above: the melting of the Arctic ice cap, and other sea ice such as the Ross ice shelf will make no difference to sea levels, because of the reasons causing Robonson confusion.

The melting of mountain glaciers, the Greenland ice cap, the Antarctic ice cap, or any combination, would cause a rise in sea levels, because water currently sequestered on land as ice wou ld be added to the total volume of water in the seas