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Post by Graeme on Dec 11, 2009 0:08:56 GMT
I've yet to find one reference suggesting satellite data is calibrated to the surface. The wikipedia article on the subject doesn't explicitly say it's calibrated against surface data, but it's implied.
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Post by magellan on Dec 11, 2009 0:24:44 GMT
To those who have problems with Hadcrut why don't we use UAH . I reckon 2010 will be second warmest year on record. The 'cooling trend' is over. I've yet to find one reference suggesting satellite data is calibrated to the surface. There isn't one - not a reliable one anyway. The 'cooling trend' is over. Until the next La Nina, then what?
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Post by Graeme on Dec 11, 2009 0:27:49 GMT
Found a reference to using surface temperatures to calibrate satellite data: www.cmar.csiro.au/remotesensing/oceancurrents/ten_years_of_SST.docThe comment is on page 5 of this document, under the heading of "Sea Surface Temperature" (my highlighting on the sentence in question): The AVHRR thermal bands at 3.7, 11 and 12 ìm are used to derive SST. The 3.7 ìm band is affected by solar irradiance during the day and can only be used for SST calculation at night. SST algorithms try to exploit differences in the atmospheric transmissivity of two or more frequencies to adjust for the effect of the atmosphere and derive a surface temperature. The algorithms have a theoretical basis but are often empirically calibrated using bulk surface measurements. There are two SST algorithms used in this study. The first was developed by McMillin and Crosby (1984) and is applied to data from the NOAA 9 and 12 AVHRR data. The SST are calculated using the expression SST = a0 + T11 + a1(T11 – T12) where T11 and T12 are the 11 and 12 ìm brightness temperatures and a0 = -0.582, and a1 = 2.702. Subsequent data (NOAA 11, 14, 16 and 17) are analysed using the NOAA Nonlinear SST algorithm developed by NOAA (Sullivan et al, 1993) provides slightly more accurate results. There is a separate day and a night algorithm and a dependency on view angle included in this algorithm.
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Post by magellan on Dec 11, 2009 1:01:58 GMT
Found a reference to using surface temperatures to calibrate satellite data: www.cmar.csiro.au/remotesensing/oceancurrents/ten_years_of_SST.docThe comment is on page 5 of this document, under the heading of "Sea Surface Temperature" (my highlighting on the sentence in question): The AVHRR thermal bands at 3.7, 11 and 12 ìm are used to derive SST. The 3.7 ìm band is affected by solar irradiance during the day and can only be used for SST calculation at night. SST algorithms try to exploit differences in the atmospheric transmissivity of two or more frequencies to adjust for the effect of the atmosphere and derive a surface temperature. The algorithms have a theoretical basis but are often empirically calibrated using bulk surface measurements. There are two SST algorithms used in this study. The first was developed by McMillin and Crosby (1984) and is applied to data from the NOAA 9 and 12 AVHRR data. The SST are calculated using the expression SST = a0 + T11 + a1(T11 – T12) where T11 and T12 are the 11 and 12 ìm brightness temperatures and a0 = -0.582, and a1 = 2.702. Subsequent data (NOAA 11, 14, 16 and 17) are analysed using the NOAA Nonlinear SST algorithm developed by NOAA (Sullivan et al, 1993) provides slightly more accurate results. There is a separate day and a night algorithm and a dependency on view angle included in this algorithm. Yes, but that is for SST?? which would seem logical. In any event, This at WUWT: wattsupwiththat.com/2008/03/08/putting-a-myth-about-uah-and-rss-satellite-data-to-rest/ “No other data are used in the construction. That is why we can do comparison studies without any interdependence.”
Monckton revised his essay and I suspect it's because someone flagged Christy or Spencer or Mears.
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Post by hairball on Dec 11, 2009 1:10:55 GMT
Mebbe I'm a bit slow but wouldn't the snowstorm over 46 US states totally obliterate, and more, the El Nino in terms of global temperature at least for this month?
As for the poll question, I think that the last decade of stagnant temperatures (and it's a wild assumption that there wasn't cooling considering the AGW nutjobs "handling" the data) were like the top of the first hill of a rollercoaster and next year everybody is going to notice the obvious cooling. This is based mainly on my psychic abilities and the fact that I wouldn't trust an elite climatologist any further than I could throw them. And that's really saying something when you consider Mann et al.
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Post by cnlmustard on Dec 11, 2009 2:31:15 GMT
There used to always be a comical attitude toward people with thier "conspiracy theories". And now we have the East Anglia emails. I don't believe anymore that they are ALL nut-jobs.
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Post by Graeme on Dec 11, 2009 2:55:32 GMT
Yes, but that is for SST?? which would seem logical. It was all I could find. ;D What was more interesting was the information that while the satellites have a 0.5 degree error margin (I presume that is celsius, since it's an Australian website), the actual error margin is around one degree because the satellites can give false readings due to atmospheric effects: The accuracy of the temperature measure is limited to half a degree by the satellite instrument and then further degraded by atmospheric effects including undetected cloud, to the order of a degree. Anyway, I think this is all off topic....
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Post by atra on Dec 11, 2009 7:43:03 GMT
We currently have an El Nino that is similar or stronger than the Winter 06/07 El Nino that peaked UAH temps at +0.6.
It's expected that our current El Nino will weaken to neutral next year or even turn into La Nina.
There is no carbon dioxide temperature signal in the UAH data and i don't expect that to change in one year.
Therefore, i expect 2010 temps to be lower than 2009.
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Post by northsphinx on Dec 11, 2009 8:23:24 GMT
El Nino, NAO and PDO is all natural and do change the climate. Not the other way around. That does even AGW-istas agree on.
Here far north in Scandinavia is weather a matter of which direction the wind comes from. If the wind persist for longer period will the climate change. Weather will change the temperature. Not the other way around. That make me strongly believe that the climate is a result of the wind pattern. And wind pattern drives ocean current. Here is a strong forcing. Wind forcing.
And what drives the wind and its direction? What control, start and stop an El Nino, reverse PDO, keeps the polar vortex etc.
That is unknown so far. But that makes the weather and over time our climate. I suspect that our planet wind pattern responds to the suns activity and that change our climate. All measurement of local temperatures is then a measurement of the result of the wind pattern.
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Post by glc on Dec 11, 2009 9:36:01 GMT
Can we just say for now that as far as the atmospheric readings are concerned, i.e. Lower Trop, Mid Trop, etc are concerned UAH satellite analysis does not employ any calibration involving the surface temperatures.
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Post by glc on Dec 11, 2009 9:39:34 GMT
The 'cooling trend' is over. Until the next La Nina, then what?But each La Nina is warmer than the previous one, so providing we choose a sufficiently long time period the trend will always be up. Choose a period which is less than 10 years and you can show any trend you want.
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Post by steve on Dec 11, 2009 11:32:40 GMT
Feel free to answer the poll for which ever dataset you like, and use a local one if you prefer. Though remember that even the almighty USA is only 2% of the earth's surface. I think magellan is right in saying that Christy et al have said that the satellite measurements are independent. So use one of those if you want to avoid surface stations.
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Post by aj1983 on Dec 11, 2009 13:46:39 GMT
...but with one small change. I think it will be El Niño plus increasing solar activity that will make 2010 warmer than this year. I'm not going to try to put a figure on it, though, because that would be a pure guess as I don't know enough to be able to judge the effects of these two items. You expect that increasing solar activity will already increase temperatures next year? That makes me wonder why it didn't cool down substantially last 3 years. Nobody exactly knows what will happen next year, but I don't expect it to be a record (warmer than 1998) year. The sun has been VERY inactive for 3 years now, and as temperatures are probably going to lag a bit, next year might still be influenced by that. On the other hand, El Nino and AGW will have a positive influence. I'll give it a try: HaDCRUT will be around 0.45 so roughly equal or slightly warmer than this year. It's interesting though how they can get up with numbers with a one thousand of a degree certainty. Most thermometers have much larger uncertainties, and there can be offsets due to interpolation/places with no data. Probably they average so many stations that they can come up with such a degree of certainty, but for me it's hard to believe that they can determine the global temperature in such detail.
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Post by sfbmikey on Dec 11, 2009 16:58:09 GMT
I suspect a cooler year (a smidge warmer than 2008), with the el nino switcheroo occurring early.
Part of this is my belief that the cyclical climate trends in the 30 year range have been grossly underestimated, and we are now dipping down as we did in the 50s (although this dip will be warmer than that).
complicated by the unpredictable 2009. It was a friggin roller coaster ride, UAH .003 in june, .411 in july. yikes!
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Post by magellan on Dec 11, 2009 17:55:37 GMT
The 'cooling trend' is over. Until the next La Nina, then what?But each La Nina is warmer than the previous one, so providing we choose a sufficiently long time period the trend will always be up. Choose a period which is less than 10 years and you can show any trend you want. Two La Nina's this decade, not counting 1999/2000 following 97/98 'super El Nino'. 2000/2001 was classified as weak 2007/2008 was classified as moderate So your statement each La Nina is weaker than the previous is unfounded. Yet, this decade was dominated by positive ONI and no net warming. What does that say? Spencer noted there was near twice the radiative forcing than would be from CO2, yet no warming. As Trenberth acknowledged, it truly is a "travesty" it cannot be explained. El Nino- releasing heat La Nina- recharge of heat One thing is certain: CO2 is in no way related to these swings in temperature. Choose a period which is less than 10 years and you can show any trend you want.
So what then, look up daily data and create a "trend"? Puhleeze. We don't get to make up our own statistical methods as we along, well at least not honest scientists. The fact is, there has been no statistically significant warming for at least 12 years. 2007/2008 is a conundrum all by itself. Can you explain it? icecap.us/images/uploads/05-loehleNEW.pdf
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