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#111
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Global Warming/Climate Change (was contrails)
On Jan 8, 11:48*am, delboy wrote:
On 8 Jan, 11:25, Tom Gardner wrote: On Jan 8, 6:35*am, delboy wrote: On 29 Dec 2009, 17:14, Martin Gregorie wrote: On Tue, 29 Dec 2009 05:01:59 -0800, Tom Gardner wrote: ObJoke: we don't have climate, we have weather! Hence the saying "Climate is what you expect, weather is what you get". We are having a very cold winter in the UK and Northern Europe (and so I understand is North America). The whole of the UK is blanketed in snow and gliding here has largely come to a halt. We also had a relatively cold winter last year. So the questions a 1) Are we entering another mini or maxi ice age? Insufficient evidence to know which way things will tip, but a good precursor of a flip to a different regime would be more frequent extreme weather conditions. 2) Is man made global warming/climate change a scam dreamed up by unscrupulous politicians, so they can control and tax us more? They fund the scientists who are trying to prove the case, but not the sceptical ones. Can I suggest you put the tinfoil hat back on. What on earth makes you dream that they need *extra* powers/reasons/arguments/etc to tax and control us! 3) Will sea levels rise when all the snow and ice on the UK eventually melts (tongue in cheek question)? 4) If the cold winter is down to recent man made global warming/ climate change, we also had particularly cold winters in 1982, 1962/63, 1948, and during the mini ice age period in the 14th - 19th century. What caused them? Prior to the mini ice age, the British Isles were warm enough to be a noted wine growing area! Anybody suggesting one year's *weather* as a indication of *climate* change is a prime candidate for buying a secondhand bridge in New York!- Hide quoted text - - Show quoted text - Hi Tom, 1) On the control/taxation issue, you obviously don't live in the Nu Labour governed UK. They are always looking for new ways to tax us, and green issues give them a good excuse to do so. They have already introduced Airport Travel Taxes and extra duties on motor fuels and large engined cars. Er, I do live in England. They don't need _*extra*_ powers etc (double emphasis since you missed the emphasis in my last message). If you think that the coming deluge of new taxes is something to do with New Labour (i.e Margaret Thatcher's greatest achievement) then you (a) don't understand the depth of the current financial problems and (b) are going to be surprised after the next election. 2) The point I am trying to make (at least in my last posting) is that there is good evidence that the climate has been variable before, with naturally cold and warm periods. The fact that measured global temperatures have increased by a fraction of a degree over the last 100 years, and the ice caps are melting, doesn't necessarily mean that this will be a continuing trend. Of course. Only a fool would look at a single piece of evidence and make dire predictions. In addition, only a fool (or ostrich) doesn't attempt to extrapolate current trends with associated sensitivity analyses. The climate scientists look at history and pre-history and many many snippets of current data. This isn't exactly a new discipline - it has been gathering momentum for the past 30 years. Just what evidence would you require before you believed that climate change is real? Is it possible to have such evidence in time to avert climate change? |
#112
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Global Warming/Climate Change (was contrails)
On Jan 8, 11:30*am, Scott wrote:
Here's an interesting picture of a bunch of folks protesting against global warming....rather interesting... http://www.consumerenergyreport.com/...-attend-global... Excellent |
#113
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Global Warming/Climate Change (was contrails)
On 8 Jan, 12:08, Tom Gardner wrote:
Just what evidence would you require before you believed that climate change is real? Is it possible to have such evidence in time to avert climate change? This seems as good as anything: http://www.kusi.com/home/78477082.html?video=pop&t=a As plants consume CO2 for photosynthesis, deforestation and land clearance (particularly if it then turns into a desert) worry me more than burning fossil fuels. With enough plant life, the Carbon in CO2 is naturally recycled. As the Earth has maintained reasonably stable temperatures (with relatively minor variations) for billions of years, it must have pretty good natural control and feedback mechanisms. Otherwise life on it would have already died out. Derek Copeland |
#114
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OT ( was: Global Warming/Climate Change ...)
delboy wrote some questions, and asked for answers: I am glad to oblige:
We are having a very cold winter in the UK and Northern Europe (and so I understand is North America). The whole of the UK is blanketed in snow and gliding here has largely come to a halt. We also had a relatively cold winter last year. So the questions a 1) Are we entering another mini or maxi ice age? No, unfortunately. 2) Is man made global warming/climate change a scam dreamed up by unscrupulous politicians, so they can control and tax us more? They fund the scientists who are trying to prove the case, but not the sceptical ones. Any major effect will find its entrepreneurs and con men. The unscrupulous politicians of my knowledge have been very slow to pick up on the long term warming trend. Research meteorologists have been slow too (IMO) to pick up on the greater variability that seems to be going along with the trend. 3) Will sea levels rise when all the snow and ice on the UK eventually melts (tongue in cheek question)? Yes, but that melt will be hard to measure. Much easier, will be the upcoming shelf slip and melt in the Antarctic. That will just take a stick planted in a tidal flow, anywhere. 4) If the cold winter is down to recent man made global warming/ climate change, we also had particularly cold winters in 1982, 1962/63, 1948, and during the mini ice age period in the 14th - 19th century. What caused them? Prior to the mini ice age, the British Isles were warm enough to be a noted wine growing area! Derek Copeland Dunno. That was then, and this is now. Pleased to be of service. Brian W |
#115
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OT (was Global Warming/Climate Change ...)
delboy wrote:
there is good evidence that the climate has been variable before, with naturally cold and warm periods. The fact that measured global temperatures have increased by a fraction of a degree over the last 100 years, and the ice caps are melting, doesn't necessarily mean that this will be a continuing trend. Derek Copeland This point has to be conceded. After an observation comes the stage of attempting to associate it with other factors, in order to establish a causal link. When the observation is global, modulating the links thought to be causal is not easy, particularly when they cut through the classical path to the improvement of National living standards in many places. Brian W |
#116
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OT ( was: Global Warming/Climate Change ...)
On 8 Jan, 12:52, brian whatcott wrote:
delboy wrote some questions, and asked for answers: I am glad to oblige: We are having a very cold winter in the UK and Northern Europe (and so I understand is North America). The whole of the UK is blanketed in snow and gliding here has largely come to a halt. We also had a relatively cold winter last year. So the questions a 1) Are we entering another mini or maxi ice age? No, unfortunately. 2) Is man made global warming/climate change a scam dreamed up by unscrupulous politicians, so they can control and tax us more? They fund the scientists who are trying to prove the case, but not the sceptical ones. Any major effect will find its entrepreneurs and con men. The unscrupulous politicians of my knowledge have been very slow to pick up on the long term warming trend. * * *Research meteorologists have been slow too (IMO) to pick up on the greater variability that seems to be going along with the trend. 3) Will sea levels rise when all the snow and ice on the UK eventually melts (tongue in cheek question)? Yes, but that melt will be hard to measure. Much easier, will be the upcoming shelf slip and melt in the Antarctic. * That will just take a stick planted in a tidal flow, anywhere. 4) If the cold winter is down to recent man made global warming/ climate change, we also had particularly cold winters in 1982, 1962/63, 1948, and during the mini ice age period in the 14th - 19th century. What caused them? Prior to the mini ice age, the British Isles were warm enough to be a noted wine growing area! Derek Copeland Dunno. That was then, and this is now. Pleased to be of service. Brian W The amount of water currently tied up as snow and ice on the UK landmass is almost negligible in the whole scheme of things, and in any case the sea level after the thaw (assuming we get one) will be the same as it was before. The melting of polar sea ice would not have anything like the great effect on sea levels that people seem to think it should. It is slightly less dense than cold water, so floats on top, displacing its own weight of water. The Earth's gravity keeps water (displaced or otherwise) at the same level throughout the globe, give or take a bit for tides caused by the gravity of the moon. Melting of the ice caps on landmasses such as Greenland and Antartica would have a much more significant effect. Derek Copeland |
#117
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Global Warming/Climate Change (was contrails)
On Jan 8, 12:42*pm, delboy wrote:
As the Earth has maintained reasonably stable temperatures (with relatively minor variations) for billions of years, it must have pretty good natural control and feedback mechanisms. Otherwise life on it would have already died out. Um, which planet earth do you live on? There have been multiple "extinction events" which take all of 5 seconds to find on wackypedia. In particular, the "clathrate gun hypothesis" is particularly relevant. A snippet to whet your appetite... The clathrate gun hypothesis is the popular name given to the hypothesis that rises in sea temperatures (and/or falls in sea level) can trigger the sudden release of methane from methane clathrate compounds buried in seabeds and permafrost which, because the methane itself is a powerful greenhouse gas, leads to further temperature rise and further methane clathrate destabilization – in effect initiating a runaway process, as irreversible once started as the firing of a gun ... However there is stronger evidence that runaway methane clathrate breakdown may have caused drastic alteration of the ocean environment and the atmosphere of earth on a number of occasions in the past, over timescales of tens of thousands of years; most notably in connection with the Permian extinction event, when 96% of all marine species became extinct 251 million years ago. Sounds pretty drastic to me! |
#118
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Global Warming/Climate Change (was contrails)
On Fri, 08 Jan 2010 03:48:08 -0800, delboy wrote:
2) The point I am trying to make (at least in my last posting) is that there is good evidence that the climate has been variable before, with naturally cold and warm periods. The fact that measured global temperatures have increased by a fraction of a degree over the last 100 years, and the ice caps are melting, doesn't necessarily mean that this will be a continuing trend. There are hints in fairly reputable circles, e.g. New Scientist, that there could be two opposing effects operating: On the warming side the greenhouse effect forced by rising carbon dioxide levels from burning foosil fuel and by rising methane levels from agriculture, melting permafrost and (some say) sublimation of methane clathrates On the cooling side the extended quite sun effect. The sun has now been stuck in its sunspot minimum for the last two years. A very long quiet sun coincided with the Little Ice Age. The hypothesis is that: - during a solar minimum the solar wind is also at a minimum (known fact) - if the solar wind is reduced, so is size of the sun's magnetosphere (known fact) - the magnetosphere deflects cosmic rays, which are high energy charged particles from outside the solar system - more cosmic rays cause more clouds as they disintegrate in our atmosphere and ionise it. - hence a prolonged solar minimum causes cloudier weather. - increased cloudiness reflects more sunlight, cooling the earth (known fact) Hence a long solar minimum will start a cooling trend if it lasts long enough to propagate outward far enough to affect the size of the solar magnetosphere. The solar wind travels at 400-750 km/s, the heliopause is around 150 AU in radius, so you'd expect to see this cooling effect to start between 1 and 2 years after a long solar minimum started. NOTE: this cooling effect has nothing to do with variations in the sun's energy output, which is pretty stable though it is thought to have risen by about 25% since the earth formed. Just as well it *is* stable life as we know it would be impossible near a variable star. I'd just add that we've now had two rather poor, cloudy soaring seasons and the solar minimum started 2 years ago.... Nobody knows, or seems to know, whether the cooling associated with a solar minimum (assuming it is) is a bigger or a smaller effect than current greenhouse warming. -- martin@ | Martin Gregorie gregorie. | Essex, UK org | |
#119
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Global Warming/Climate Change (was contrails)
On 8 Jan, 16:25, Tom Gardner wrote:
.. Um, which planet earth do you live on? There have been multiple "extinction events" which take all of 5 seconds to find on wackypedia. In particular, the "clathrate gun hypothesis" is particularly relevant. A snippet to whet your appetite... * The clathrate gun hypothesis is the popular name given * to the hypothesis that rises in sea temperatures (and/or * falls in sea level) can trigger the sudden release of * methane from methane clathrate compounds buried in * seabeds and permafrost which, because the methane * itself is a powerful greenhouse gas, leads to further * temperature rise and further methane clathrate * destabilization – in effect initiating a runaway process, * as irreversible once started as the firing of a gun * ... * However there is stronger evidence that runaway methane * clathrate breakdown may have caused drastic alteration of * the ocean environment and the atmosphere of earth on a * number of occasions in the past, over timescales of tens * of thousands of years; most notably in connection with the * Permian extinction event, when 96% of all marine species * became extinct 251 million years ago. Sounds pretty drastic to me! Er! Did I say there hadn't been any mass extinctions? There have been lots of them, including the large dinosaurs (large meteorite strike?), woolly mammoths (hunting, loss of habitat), dodos (stupid birds) and even our near relatives the neanderthals (climate change - the last ice age, probably nothing to do with CO2 emissions or methane clathrates). The fact of the matter is that all life forms on Earth are water based, and with a few exceptions can only exist between about 0 - 60 degrees Centigrade, which is a tiny range in the scale of all things in the Universe. The Earth is supposed to be a 'Goldilocks' planet: Not too close to the Sun, not too far away, but just right! I believe that methane releases are one possible explanation for the many ships lost in the Bermuda Triangle. If there are a lot of methane bubbles in the sea water, then it becomes insufficiently dense to support the vessel and it just sinks! Of course it could just be pirates. Derek Copeland |
#120
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Global Warming/Climate Change (was contrails)
On Thu, 07 Jan 2010 23:59:25 -0800, delboy wrote:
The argument you are putting forward is that sea ice and the snow on top of it will melt due to global warming and, being lower in salt content, will dilute the salinity of oceans. In fact I wouldn't be surprised to see an increase in sea ice this year. These things are cyclical, and apparently there was little sea ice in the Medieval mini warm period between the 9th and 13th Centuries. This allowed the Vikings to settle in Iceland and Greenland. The ones in Greenland were wiped out by cold weather in the 15th century. See: http://en.wikipedia.org/wiki/Little_Ice_Age The best reference I've seen so far about this is: http://www2.sunysuffolk.edu/mandias/lia/index.html A page of it was originally quoted to show how far the Gulf Stream's effects extend into the Arctic but I found the whole thing a most interesting read. -- martin@ | Martin Gregorie gregorie. | Essex, UK org | |
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