... was the headline in yesterday's Metro. I immediately searched the BBC website to see what they made of it, but they didn't cover the story until this afternoon, with the inevitable BBC/Met Office spin:
The UK had its coldest winter for 13 years, bucking a recent trend of mild temperatures, the Met Office has said. The average mean temperature across December, January and February was 3.1C - the lowest since the winter beginning in 1995, which averaged 2.5C...
Peter Stott, of the Met Office, said despite this year's chill, the trend to milder, wetter winters would continue. He said snow and frost would become less of a feature in the future. "The famously cold winter of 1962/63 is now expected to occur about once every 1,000 years or more, compared with approximately every 100 or 200 years before 1850," he said. The Met Office added that global warming had prevented this winter from being even colder.
Anyways, despite the valiant efforts of the warmenists, my underlying-warming-trend-o-meter is now down to 2,410 results, from a peak of nearly 3,000 in late January.
About That Closet
6 hours ago
21 comments:
http://www.baen.com/Library/067172052X/067172052X.htm
Fallen Angels by Larry Niven
"The Met Office added that global warming had prevented this winter from being even colder. "
Hang on. I thought that the story a while ago was that the sort of cold winter we have had were a symptom of climate change happening?
TA, keep up at the back. Last winter was unusually cold - so it was evidence of climate change, the only thing that stopped it being even more unusually cold was the underlying warming trend.
So a cold winter is proof not only of climate change but of global warming. It's like what Homer Simpson said about alcohol.
"The Met Office added that global warming had prevented this winter from being even colder."
I read that as global warming being a good thing.
It's this climate change I'm scared of, apparently that could make our winters colder by cutting off the gulf stream.
Can we use global warming to balance out the effects of climate change?
Anon, don't worry about The Gulf Stream, that is driven by the Coriolis effect and has precious little to do with temperatures.
Strangely enough the BBC blog on which I put up links proving that the author's on air assertion that the globe hadn't cooled has not only been censored (which makes it 3 out of 3)but for inexplicable reasons I am blocked from further comments there.
neil,
The BBC are a joke about this. I don't have a problem with them reporting what the IPCC or scientists say, but not once do they report when a scientist is corrected (and when said scientist even accepts the mistake) which means that AGW looks even less doom-laden.
Another thing - haven't we been hearing about how AGW is going to switch off the "conveyor belt" and bring about an ice age in the UK? As this met office guy is saying that 1962 winters aren't going to happen more than once every 1,000 years, does that mean that it's not going to happen, or how many thousands of years away is he thinking? And really, if it's more than 1,000 years away, who really cares? I kinda think that 1,000 years from now that we'll be using nuclear fusion and starting to colonise other planets.
I'd put that at well under 100 years. If not for us then it will be for the Chinese.
I did see an item on the BBC news avout what England would look like following a sea level rise that some report had promised - the Thames was wider & Norfolk smaller. They then did a talking heads discussion on how this would make Chelsea uninhabitable, so people should think about moving & nuclear power stations on the shore would be destroyed.
In a corner of the map was a note that this was the forecast of sea level in 3000AD. Not sure what Chelsea looked like in 1018AD but I suspect there were fewer Range Rovers.
The Gulf Stream is not driven by the Coriolis effect; it is driven by thermohaline circulation, which has everything to do with temperature.
If the circulation, the 'conveyor belt', shut down - as it has in the past; something which wouldn't happen if it were driven by the rotation of the earth - then it would indeed lead to a European 'ice age'.
The scientific consensus is that that won't happen, at least not any time soon, because the Greenland ice sheet is too stable. It's the melting of that ice sheet that could lead to shut down, but the melt would likely need to be total and rapid.
Worries about sea level are largely based on the melting of the West Antarctic ice sheet, which is far less stable. Thanks to its instability it has the potential to collapse - resulting in sea level rises of between 5 and 7 metres - within a single human lifetime. Again; it's not expected to happen soon, but unlike Greenland it could begin this century.
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Edd - the token Greenie
Not sure the West Antarctic ice sheet is that vulnerable. It may have been slighlty shrinking, though by less ice that the rest of Antarctica is increasing but that is most likely because the colcano there is more active.
James Hansen was recently caught bu Stephen McIntyre (again) "accidentally" faking readings for temperature there which suggests there is actually no problem.
Edd, run that by me again. I get that fresh water (i.e. melted ice) and warm water is lighter than salty water or cold water, but what makes it go round in a big circle?
WAIS is vulnerable because it is grounded below sea level, because it is losing its ice shelves and because temperatures and melt levels are increasing. It's the first two aspects that are most important; they're the reasons it has collapsed several times in the past even while the East Antarctic sheet remained stable.
Whatever you may think of Hansen - and whatever I may think of McIntyre - he's not exactly the only scientist studying Antarctica.
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Edd
MW:
It's not just a big circle; it's part of a complex circulation that spans all the major oceans. The immediate driver though is density - variations in that density - caused by both temperature and salinity variations. The dense water sinks, and in doing so is constrained by the features of the ocean floor. It flows downhill, through the deep basins and trenches.
There are also warm surface currents that form part of the circulation, but from what I recall they largely move in reaction to the deep cold/salty currents. Without the deep currents the surface currents stop, and have more than once in the past. The whole thing has shut down in the past, killing nearly all the life in the oceans.
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Edd
Edd, "The dense water sinks, and in doing so is constrained by the features of the ocean floor. It flows downhill, through the deep basins and trenches."
Sure. So why doesn't the cold water sink to the deepest part of the North Atlantic and the warm water just float around aimlessly on top?
I found this shock-horror-article that says the cold flows have reduced by 30% over the last half century but also "Although no change was seen to the northward flow of warm water near the ocean surface, the movement back of deep cold water had reduced significantly."
Water is at its heaviest at 4 C, after that it starts turning to ice. This means that the deepest ocean water & surface water at the poles are the same te,perature & water at the polls instead of cooling further slips to the deep equatorial, ocean & warmer equatorial waters flow, driving the Gulf Stream, to replace them.
NC, that still doesn't explain what makes it go round in a big anti-clockwise circle. Why, for example, does heated water from the African coast not flow westwards and then up the Eastern Seaboard?
So why doesn't the cold water sink to the deepest part of the North Atlantic and the warm water just float around aimlessly on top?
Because it can't maintain its different density; as it flows it mixes with the surrounding water. There's also a continuous input of new colder water, maintaining the flow. As that cold water sinks it is replaced by warmer water flowing on the surface. The ultimate driver of all that is heat. Directly in the form of surface warming and the meltwater, and indirectly in the case of climate; the winds that increase the surface evaporation which increases salinity.
According to that article, the authors of the paper did say that the circulation isn't expected to shut down.
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Edd
Why, for example, does heated water from the African coast not flow westwards and then up the Eastern Seaboard?
It pretty much does, from southern Africa anyway:
Wiki
As you can see, it's not a big anti-clockwise circle.
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Edd
Edd, look, from what you have explained, I would expect warm water to flow away from the Equator and directly towards the poles, while water from the poles slides down a bit.
But neither you nor NC have explained the anti-clockwise bit (or clockwise if you're in the Southern Hemisphere).
It may be that coriolis forces keep the Gulf Stream on the eastern side of the Atlantic, I must admit I don't know but wouldn't be surprised. But the main driver is differential equatorial heating.
The rotation of the earth does influence the specific direction of currents, but it doesn't drive them. They exist due to other factors and can stop - have stopped - despite the fact that the earth has not yet stopped rotating.
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Edd
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