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Post by steve on Jan 6, 2010 11:14:11 GMT
Nautonnier
Do you know what the word "if" means? If you would like to reread what I said with a bit more care, then you might find that what you said was not relevant.
In other words, if for some reason, the model was started with initial conditions that were somewhat different from the average climate (eg. an analysis of the atmosphere taken during a strong El Niño or a strong La Niña) then it may be that the radiative change from your artificial instantaneous doubling of CO2, done as a thought experiment, will be different from 3.7W/m^2 because the composition of the atmosphere (in terms of cloud, warmth and water vapour distribution) will be different.
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Post by steve on Jan 6, 2010 11:31:17 GMT
And north Africa, the Middle East, Northern canada and Alaska, the former soviet states to the south of Russia, Greenland, Indonesia and the Phillipines. I don't know about North Africa/ME. But I do know that Northern Canada and Alaska are certainly not hot. I am sure the folks in Yellowknife would welcome some of that heat tho. Warmth is relative. Yellowknife is currently about 10C warmer than average for this time of year. worldweather.wmo.int/056/c00615.htm
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Post by sigurdur on Jan 6, 2010 11:36:59 GMT
I don't know about North Africa/ME. But I do know that Northern Canada and Alaska are certainly not hot. I am sure the folks in Yellowknife would welcome some of that heat tho. Warmth is relative. Yellowknife is currently about 10C warmer than average for this time of year. worldweather.wmo.int/056/c00615.htmAwww.......It hasn't been.....nor is at present. The forcast is for snow and warmer temps. www.weatheroffice.gc.ca/city/pages/nt-24_metric_e.html
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Post by steve on Jan 6, 2010 12:01:39 GMT
Oops, sorry, that was a forecast for later today. Quebec, Iqaluit and St Johns are warm now. And it's a balmy -21C north-west of Yellowknife, at Tuktoyaktuk.
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Post by sigurdur on Jan 6, 2010 12:35:30 GMT
Steve: I watch the temps around Yellowknife daily as they normally lead the temps in my area by about a week.
Even the warmth predicted there is northing unusual for this time of year as there is snow in the forcast for them.
I hope Britian doesn't suffer too much from the winter of 2009-2010. It would appear that the MET needs to realize that their models have holes in them as they have been so wrong in their long term forcasts consecutively.
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Post by nautonnier on Jan 6, 2010 13:08:16 GMT
Nautonnier Do you know what the word "if" means? If you would like to reread what I said with a bit more care, then you might find that what you said was not relevant. In other words, if for some reason, the model was started with initial conditions that were somewhat different from the average climate (eg. an analysis of the atmosphere taken during a strong El Niño or a strong La Niña) then it may be that the radiative change from your artificial instantaneous doubling of CO2, done as a thought experiment, will be different from 3.7W/m^2 because the composition of the atmosphere (in terms of cloud, warmth and water vapour distribution) will be different. You miss my point. This is not modeling a real world El Nino or La Nina or volcanic eruption. It is an imaginary scenario and yet you persist in using the 3.7WM -2 as if it were writ in stone. Tell me in a REAL WORLD example how you can INSTANTANEOUSLY double CO 2 in a well mixed atmosphere with no other atmosphere changes allowed - which is the ONLY way you can get the radiative forcing of 3.7WM -2. So by all means use this imaginary figure as a comparator. But do NOT use it in any modeling of the real world - that is totally incorrect.
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Post by steve on Jan 6, 2010 13:26:43 GMT
No you are missing my point. I am using a thought experiment to point out that the 3.7 number is *not* written in stone. It is simply a result of applying radiative transfer equations to the, presumably typical, atmosphere profile chosen by Myrrhe in 1998.
Each model will apply some version of these equations to the whole atmosphere every time iteration. I was using an instantaneous doubling as an illustration of where the 3.7 figure comes from. In a model that is being used to do a 21st Century projection, the greenhouse gas amounts will probably increase gradually as time passes, so the impacts of any radiation imbalance induced by the increase in the greenhouse gas will also apply incrementally.
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Post by steve on Jan 6, 2010 13:39:37 GMT
Steve: I watch the temps around Yellowknife daily as they normally lead the temps in my area by about a week. Even the warmth predicted there is northing unusual for this time of year as there is snow in the forcast for them. I hope Britian doesn't suffer too much from the winter of 2009-2010. It would appear that the MET needs to realize that their models have holes in them as they have been so wrong in their long term forcasts consecutively. Sigurdur, I'm simply listing a lot of "anomalously warm" places to point out that the "anomalously cold" europe is just weather, not climate. Joe Bastardi has noticed that the cold seems focused on areas with high population in the northern latitudes, and so is spinning it in an "anti-AGW" and "anti-establishment" way. The Met office forecast is a probability forecast. That's why they say 30% chance of this, 40% chance of that etc. I can't possibly see how such info could be useful to any individual person, but they obviously think it's useful to promote. Note that if you are predicting a 2/3 chance of some fact about a summer and then a winter forecast, then you will be wrong on both about one in nine times. If you are never wrong on both, then your probabilities are set too conservatively, or your predictions are set too broadly.
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Post by sigurdur on Jan 6, 2010 14:12:40 GMT
Steve: I watch the temps around Yellowknife daily as they normally lead the temps in my area by about a week. Even the warmth predicted there is northing unusual for this time of year as there is snow in the forcast for them. I hope Britian doesn't suffer too much from the winter of 2009-2010. It would appear that the MET needs to realize that their models have holes in them as they have been so wrong in their long term forcasts consecutively. Sigurdur, I'm simply listing a lot of "anomalously warm" places to point out that the "anomalously cold" europe is just weather, not climate. Joe Bastardi has noticed that the cold seems focused on areas with high population in the northern latitudes, and so is spinning it in an "anti-AGW" and "anti-establishment" way. The Met office forecast is a probability forecast. That's why they say 30% chance of this, 40% chance of that etc. I can't possibly see how such info could be useful to any individual person, but they obviously think it's useful to promote. Note that if you are predicting a 2/3 chance of some fact about a summer and then a winter forecast, then you will be wrong on both about one in nine times. If you are never wrong on both, then your probabilities are set too conservatively, or your predictions are set too broadly. Steve: Yes, they are issuing probabilities. But the problem is....government over there seems to rely on those probabilities. The Yukon/Yellowknife etc are not a hot spot as the temp flucuation there is quit normal. IF it stays in the -20C range for lows for over 4-5 days, then it is something to look at as that would NOT be normal for this time of year. In North Dakota, we usually get a chinook in Jan. That hasn't happened now for the past 4 years. I used to haul spuds 40 miles, depending on that chinook in early Jan as it always had happened in the past. People, where it has warmed, have become quit accustomed to that warmth it would seem. Looking from the outside, I do think your government has created a travesty for your citizens. Being in government on a local scale, I just would never allow what is happending in Britian to happen in ND. Of course, most of us in ND do not adhere to the AGW theory, and prepare for what we consider our normal weather. Anyways, enough politics. But you really do need a change in leadership over there. One which does examine the actual science behind the climate and realize that it is still very infant in advancement.
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Post by icefisher on Jan 6, 2010 16:05:40 GMT
A little premature on that. The forecast is for sunny weather. As I am posting this reply the report for 8am at the Yellowknife Airport is it is "currently" -30C. Forecast is for a high of -19 and a -15C minimum tomorrow falling to a -36 minimum again on Sunday. Some heatwave Steve! The mean January temperature minimum is -30.9 and the mean January maximum is -22.7.
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Post by steve on Jan 6, 2010 16:37:48 GMT
See above, Icefisher.
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Post by poitsplace on Jan 6, 2010 17:04:41 GMT
Just look at the IPCC projections though. They quite clearly do not take into account that convection would increase as the gradient increases. The lower limit of IPCC temperatures should assume ONLY the warming from CO2...which would mean an anomaly of about 1C. Even the error bars of the models don't get that low...how can you not see a problem with that??? CLEARLY the models are mostly about feedback...since even the warming caused by the theoretical maximum for CO2 absorption (which is its self questionable) would fall outside the error bars and therefore disprove the models.
If we ignore the error bars and look at the ACTUAL predictions...the absolute minimum temperature increase requires a doubling of the theoretical maximum forcing from CO2. Of course, the theoretical maximum its self is an unrealistic figure. The most we could expect would be about half to three quarters of that figure...which means the lowest estimate its self technically requires feedbacks 2.6 to 4 times the initial forcing. The high end estimates require 4.6 to 7 times the initial forcing. These are INCREDIBLY powerful feedbacks...too powerful.
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Post by steve on Jan 6, 2010 17:29:59 GMT
Gradient of what?
I don't understand how you can claim you ought to assume the possibility of no feedbacks when all the evidence of past climate change indicates that feedbacks are positive.
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Post by hairball on Jan 6, 2010 17:50:27 GMT
Dare I ask who fabricated all this evidence? Did it involve a supercomputer?
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Post by nautonnier on Jan 6, 2010 17:56:42 GMT
Gradient of what? I don't understand how you can claim you ought to assume the possibility of no feedbacks when all the evidence of past climate change indicates that feedbacks are positive. Steve, can you give a reference on the the identity and magnitude of these feedbacks _required_ for past climate change?
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