2010 Global Temps

[BethesdaWX]

And the satellites corroborate the spatial pattern of the warmth shown on GISS.

Therefore any problem that exists with GISS also exists with HadCRUT ... GISS and HadCRUT are in agreement in the areas they both cover. The discrepancy between the two is that HadCRUT has missing warmth in the arctic. The satellites actually PROVE that HadCRUT is missing a ton of rapid warming in the arctic. For example... take HadCRUT.. then use the satellites to fill in the areas that HadCRUT is missing... you have basically the same thing as GISS.

Therefore any problem that exists is with the physical thermometers themselves... not the algorithm or methodology used. If you are blaming GISS you must also blame HadCRUT since they basically agree except HadCRUT is missing the arctic warmth that we know is occurring.

OR

1) the problem is with UAH and RSS (which is quite possible given the large discrepancy BETWEEN RSS and UAH and the LARGE corrections that have been made in the past)

2) Lower tropospheric amplification is not occuring for a yet unknown reason.

HADCRUT & GISS disagree immensly, more than UAH & RSS. HADCRUT has more data in the arctic than GISS does....GISS is Too warm..... & deleted their arctic data for some reason.

As should be said, if anyones off in the arctic its GISS. Satellites & Surface OBS are not the same thing, remember, so one cannot go and say HADCRUT is missing warmth because of UAH & RSS....GISS is off. Even so, the arctic is loke 5% of the globe, so it would not do anything too signficant, so the answer lies elsewhere anyway, most likely

It goes against AGW law for surface to warm faster HADCRUT has more data by a long shot, and it so happens HADCRUT is less error prone & apparently more accurate.

[skierinvermont]

HADCRUT & GISS disagree immensly, more than UAH & RSS. HADCRUT has more data in the arctic than GISS does....GISS is Too warm..... & deleted their arctic data for some reason.

As should be said, if anyones off in the arctic its GISS. Satellites & Surface OBS are not the same thing, remember, so one cannot go and say HADCRUT is missing warmth because of UAH & RSS....GISS is off. Even so, the arctic is loke 5% of the globe, so it would not do anything too signficant, so the answer lies elsewhere anyway, most likely

It goes against AGW law for surface to warm faster HADCRUT has more data by a long shot, and it so happens HADCRUT is less error prone & apparently more accurate.

No actually the difference between the 30 year trend is larger for UAH vs RSS than for HadCRUT vs GISS. In other words, GISS and Had are closer than UAH and RSS for the last 30 years. UAH is the outlier by far.

The satellites show fast warming in the arctic where HadCRUT doesn't cover - this proves HadCRUT is too low. Reanalysis from NCEP and ECMWF also say the arctic has warmed rapidly in the areas HadCRUT doesn't cover.

Not all the difference between HadCRUT and GISS can be explained by HadCRUTs lack of arctic coverage but most of it is. All of the difference between HadCRUT and GISS in 2005 was due to GISS's coverage of the arctic. GISS was actually lower than HadCRUT when you use a HadCRUT "mask " of 250km.

[tacoman25]

GISS isn't .4C above the satellites... it's only about .1-.15C above the satellites if you adjust the base period so that they both use a 1979-2000 base period.

They specifically say they don't doubt UAH and RSS because they disagree with the models. There is doubt in UAH and RSS 1) because UAH and RSS disagree with each other 2) UAH and RSS have had errors in the past

Also 3) keep in mind that RSS doesn't really disagree with the models.. it is not the same but it is pretty close.

RSS and UAH may have some disagreement, but they have not deviated as much as GISS and HadCRU the past few years. Maybe it's just due to the Arctic...but probably not.

[tacoman25]

I am adhering to objectivity; the RSS analysis doesn't show it to be this warm, as I suspected and remember seeing when it first came out for November 2010. You can see that RSS has most of the Northern Asian area around 2-3C whereas GISS looks to be around 6-7C anomaly...GISS has China as part of that warm tongue whereas RSS says it was below average. GISS also extrapolated the warmth from Alaska and the High Arctic into the Yukon and Northwest Territories, at least that's what I think happened, because the satellites say it was a cooler month for NW Canada and I specifically remember an area of -20C 850s sitting there. Also, the GISS extrapolated the Himalayas to be very warm as well. I'm not saying it wasn't a warm month in some areas, but the GISS anomalies are unlikely to have occurred, and satellites don't support such an extensive area of warmth.

Pretty glaring disagreement here, even considering GISS colder base period:

GISS:

RSS:

Yup....as I said, GISS tends to have the warmth much more widespread than other sources. Certainly makes a difference.

[tacoman25]

First of all.. the difference between the 1951-1980 and 1979-2000 base periods for the areas in question is .5-1.5C which pretty brings your two maps into very close agreement.

In some places, yes. Others, no.

[tacoman25]

First of all you are greatly exaggerating the areas that GISS has as warm that RSS doesn't ... you aren't factoring in the base period change.

Second of all .. you clearly don't understand the principle of extrapolation if you are asking that question. In some spots it will extrapolate too warm.. in others it will extrapolate too cold. Overall it evens out. Statistics.. law of large numbers. Etc... blah blah blah

No, it clearly does not, when compared to other temperature sources. The extrapolation is much more likely to lead to massive warm anomalies with GISS...which are often portrayed as more widespread than other sources show. I don't understand why you are arguing this...even with base period adjustements, GISS consistently has larger areas of warmth. A couple years ago I did a study on this and showed it on eastern...the pattern continues, and it is consistently in the same areas. And it explains why GISS consistently is the warmest source.

[tacoman25]

Make sure you check out the southern atlantic between Africa and brazil/uruguay while you're at it. RSS is way warmer... must be a conspiracy

.. and the waters off Antarctica SE of Africa

.. and the tropical pacific

If you are arguing that GISS has the oceans colder than other sources, that is certainly not correct....

[skierinvermont]

RSS and UAH may have some disagreement, but they have not deviated as much as GISS and HadCRU the past few years. Maybe it's just due to the Arctic...but probably not.

The long term trend in UAH is like .11C/decade... the same trend for RSS/GISS/HadCRUT are all like .16C/decade.

Clearly there is some difference between GISS that last few years... much of it is the arctic... some of it isn't.

[skierinvermont]

If you are arguing that GISS has the oceans colder than other sources, that is certainly not correct....

No we were arguing over one month.

[skierinvermont]

No, it clearly does not, when compared to other temperature sources. The extrapolation is much more likely to lead to massive warm anomalies with GISS...which are often portrayed as more widespread than other sources show. I don't understand why you are arguing this...even with base period adjustements, GISS consistently has larger areas of warmth. A couple years ago I did a study on this and showed it on eastern...the pattern continues, and it is consistently in the same areas. And it explains why GISS consistently is the warmest source.

Well the fact is ... if you infill HadCRUT with satellite data from UAH or reanalysis data from NCEP or ECMWF, then it explains 75%+ of the difference between GISS and HadCRUT over the last 10 years. It explains all of the difference up to 2006ish.

[tacoman25]

The long term trend in UAH is like .11C/decade... the same trend for RSS/GISS/HadCRUT are all like .16C/decade.

Clearly there is some difference between GISS that last few years... much of it is the arctic... some of it isn't.

I think that's kind of misleading, though, because it is based on UAH's starting point...which happens to be higher for whatever reason than the other sources. If you do a decade by decade comparison, I believe UAH is closer to the others.

[BethesdaWX]

No actually the difference between the 30 year trend is larger for UAH vs RSS than for HadCRUT vs GISS. In other words, GISS and Had are closer than UAH and RSS for the last 30 years. UAH is the outlier by far.

The satellites show fast warming in the arctic where HadCRUT doesn't cover - this proves HadCRUT is too low. Reanalysis from NCEP and ECMWF also say the arctic has warmed rapidly in the areas HadCRUT doesn't cover.

Not all the difference between HadCRUT and GISS. can be explained by HadCRUTs lack of arctic coverage but most of it is. All of the difference between HadCRUT and GISS in 2005 was due to GISS's coverage of the arctic. GISS was actually lower than HadCRUT when you use a HadCRUT "mask " of 250km.

Huh? HADCRUT has more coverage in the arctic than GISS You can't compare Surface & LT anoms and say HADCRUT has less warming because satellites have more, because that is LT, not Surface. HADCRUT has more data in General GISS has almost no coverage up there.

And, No, not the 30 year trend. In the Past 10 years, GISS & HADCRUT have been FAR worse that UAH & RSS.

Not a good argument at all

[skierinvermont]

I think that's kind of misleading, though, because it is based on UAH's starting point...which happens to be higher for whatever reason than the other sources. If you do a decade by decade comparison, I believe UAH is closer to the others.

No it's not based on UAH's starting point ... it's based on a linear regression. UAH is out of wack with the other 3. Which is strange since RSS and UAH are basically the same raw data.

[skierinvermont]

Huh? HADCRUT has more coverage in the arctic than GISS You can't compare Surface & LT anoms and say HADCRUT has less warming because satellites have more, because that is LT, not Surface. HADCRUT has more data in General GISS has almost no coverage up there.

And, No, not the 30 year trend. In the Past 10 years, GISS & HADCRUT have been FAR worse that UAH & RSS.

Not a good argument at all

COVERAGE. HadCRUT doesn't have any coverage in the arctic.. it leaves huge areas BLANK. We KNOW from about a dozen different sources that the areas HadCRUT is leaving blank have warmed rapidly the last 30 years. Therefore we KNOW that IF HADCRUT covered these areas, it would show more warming.

[BethesdaWX]

COVERAGE. HadCRUT doesn't have any coverage in the arctic.. it leaves huge areas BLANK. We KNOW from about a dozen different sources that the areas HadCRUT is leaving blank have warmed rapidly the last 30 years. Therefore we KNOW that IF HADCRUT covered these areas, it would show more warming.

Data is more important than coverage....if theres no data, don't extrapolate false data in there, thats why GISS is too warm............If Hadley leaves it blank, then its counted as avg, which is too cool. However, GISS is too warm, and, means......with the arctic only 5% globally, it won't make a huge difference when compared Hadley & Nasa Goddard together globally. They should wind up about the same.

As you Correctly stated, The deviation is caused by extrapolation size. Theres no reason why GISS cannot shorten their grids.

Again, LT is not Surface.

IF THEY HAVE NO DATA, THEN DON'T CREATE DATA!!!

[nzucker]

Data is more important than coverage....if theres no data, don't extrapolate false data in there, thats why GISS is too warm............If Hadley leaves it blank, then its counted as avg, which is too cool. However, GISS is too warm, and, means......with the arctic only 5% globally, it won't make a huge difference when compared Hadley & Nasa Goddard together globally. They should wind up about the same.

As you Correctly stated, The deviation is caused by extrapolation size. Theres no reason why GISS cannot shorten their grids.

Again, LT is not Surface.

IF THEY HAVE NO DATA, THEN DON'T CREATE DATA!!!

This sums it up and creates a good compromise with skier. Hadley has been running cool because of lack of arctic data, but GISS has extrapolated overly warm values there. You can clearly see that the satellites detect nuances in their measurement that GISS misses with extrapolation...you can clearly detect this in the small area of the Yukon/NW Territories that the satellites measured as near average in a region that was by and large warm. GISS just filled in the whole region with warmth because they didn't see the smaller cold area...you could actually see the cold area on models like the GFS if you followed closely...there was a weird pool of -20C 850s in the Yukon area that didn't include AK or the High Arctic. This is the problem with GISS's low resolution, it is correct in the general trend of widespread warmth in the high latitudes of the NH, but clearly misses some areas that stayed closer to the long-term normal value.

I totally agree with extrapolation being a problem. You can't come out and say "2010 was the warmest year on record" if other sources don't corroborate that, and if the satellites clearly show that areas GISS filled in with +4C were more like +2C or so. Data should never be created in this fashion, and it needs to be quality controlled using a cross-check with the satellites. If the satellites show the UK was -3C and GISS only shows -1C, that needs to be gone over, just to give one example from a slew of problems I have. Uncharacteristically large anomalies should also be checked carefully because most places don't average +6C for an entire month. Obviously it's possible to have big anomalies at northern latitudes but that is just a very large monthly departure.

[BethesdaWX]

I agree 150% dude. Skier has made good points as well.

Just wondering....when NASA declares a certain year "warmest ever"...is that official..like, really? if so, I've never seen science so horrid.

[skierinvermont]

This sums it up and creates a good compromise with skier. Hadley has been running cool because of lack of arctic data, but GISS has extrapolated overly warm values there. You can clearly see that the satellites detect nuances in their measurement that GISS misses with extrapolation...you can clearly detect this in the small area of the Yukon/NW Territories that the satellites measured as near average in a region that was by and large warm. GISS just filled in the whole region with warmth because they didn't see the smaller cold area...you could actually see the cold area on models like the GFS if you followed closely...there was a weird pool of -20C 850s in the Yukon area that didn't include AK or the High Arctic. This is the problem with GISS's low resolution, it is correct in the general trend of widespread warmth in the high latitudes of the NH, but clearly misses some areas that stayed closer to the long-term normal value.

I totally agree with extrapolation being a problem. You can't come out and say "2010 was the warmest year on record" if other sources don't corroborate that, and if the satellites clearly show that areas GISS filled in with +4C were more like +2C or so. Data should never be created in this fashion, and it needs to be quality controlled using a cross-check with the satellites. If the satellites show the UK was -3C and GISS only shows -1C, that needs to be gone over, just to give one example from a slew of problems I have. Uncharacteristically large anomalies should also be checked carefully because most places don't average +6C for an entire month. Obviously it's possible to have big anomalies at northern latitudes but that is just a very large monthly departure.

Again you continue to fail to understand the mathematical effect of extrapolation. Had one of those cool spots fallen on top of a thermometer GISS uses to extrapolate in the arctic, then GISS would have been vastly too cool. It all balances out. It's very basic really.

And this did in fact happen in numerous areas in November 2010, and every other month of GISS data. Some areas were extrapolated too cool. The most glaring is the area around the Black Sea where both NCEP and RSS place anomalies >4C all the way westward to Greece, where GISS has anomalies 1-2 and 2-4C. You seem to think you have discovered something by noticing all these areas where GISS looks to have extrapolated too warm.. when in fact all you are doing is showing your bias in failing to observe the areas in which it extrapolated far too cold.

Unless you can demonstrate a physical basis for why the thermometers GISS uses would be persistently warm biased relative to their surroundings you have no argument. You can form an accurate and fairly precise index of global temperatures using no more than 100 thermometers globally and extrapolating 2,000+km from each of them. Some extrapolations would be too warm, some too cold, but month to month, and especially year to year and decade to decade, it all balances out. GISS and HadCRUT have far far more thermometers than they need. I can select break the globe up into 100 boxes and use just 1 thermometer per box and I will come up with the exact same 100-yr warming trend as GISS and HadCRUT. Such studies have in fact been done and do in fact show the same trend as GISS and HadCRUT over the 20th century.

And many of the extrapolations would have been far FAR more horrendous than the extrapolation over the UK in November 2010 that you keep harping on as invalidating GISS and saying should have been crosschecked. And yet somehow SOMEHOW it ends up with the exact same result as GISS and HadCRUT even using less than 5% the number of thermometers that they use and extrapolating much farther than either of them.

BTW there is some basis for making the argument that GISS uses thermometers which are persistently warmer than their surroundings.. but you have failed to make that argument at all. It is possible that GISS extrapolates somewhat too much warmth because some of the thermometers GISS uses are located on coastal areas for which there is some reason to believe may have warmed more than their surroundings.

You keep attacking "extrapolation" saying it creates bias and that GISS "shouldn't extrapolate as far." This is at odds with basic statistics. Extrapolation doesn't create bias. What creates bias is if you use thermometers for which there is a physical reason to believe they are warmer than their surroundings. You have not made such an argument. The extrapolation of warmth across the UK in November 2010 doesn't create bias because it's just as likely that in other months cold will be extrapolated.

Saying that GISS should be cross-checked with the satellites means that GISS is no longer an independent source of data. You can cross check the spatial pattern of temperatures but not the amplitude. An objective comparison shows that GISS sometimes extrapolates too warm and sometimes extrapolates too cold.

It's actually sort of funny you think you can come along and tell scientists how they need to cross-check GISS. You don't think anybody else noticed that sometimes the extrapolations are going to be incorrect? You don't think anybody else bothered to do the statistical studies to see what, if any, the effect of this would be?

[BethesdaWX]

Again you continue to fail to understand the mathematical effect of extrapolation. Had one of those cool spots fallen on top of a thermometer GISS uses to extrapolate in the arctic, then GISS would have been vastly too cool. It all balances out. It's very basic really.

And this did in fact happen in numerous areas in November 2010, and every other month of GISS data. Some areas were extrapolated too cool. The most glaring is the area around the Black Sea where both NCEP and RSS place anomalies >4C all the way westward to Greece, where GISS has anomalies 1-2 and 2-4C. You seem to think you have discovered something by noticing all these areas where GISS looks to have extrapolated too warm.. when in fact all you are doing is showing your bias in failing to observe the areas in which it extrapolated far too cold.

Unless you can demonstrate a physical basis for why the thermometers GISS uses would be persistently warm biased relative to their surroundings you have no argument. You can form an accurate and fairly precise index of global temperatures using no more than 100 thermometers globally and extrapolating 2,000+km from each of them. Some extrapolations would be too warm, some too cold, but month to month, and especially year to year and decade to decade, it all balances out. GISS and HadCRUT have far far more thermometers than they need. I can select break the globe up into 100 boxes and use just 1 thermometer per box and I will come up with the exact same 100-yr warming trend as GISS and HadCRUT. Such studies have in fact been done and do in fact show the same trend as GISS and HadCRUT over the 20th century.

And many of the extrapolations would have been far FAR more horrendous than the extrapolation over the UK in November 2010 that you keep harping on as invalidating GISS and saying should have been crosschecked. And yet somehow SOMEHOW it ends up with the exact same result as GISS and HadCRUT even using less than 5% the number of thermometers that they use and extrapolating much farther than either of them.

BTW there is some basis for making the argument that GISS uses thermometers which are persistently warmer than their surroundings.. but you have failed to make that argument at all. It is possible that GISS extrapolates somewhat too much warmth because some of the thermometers GISS uses are located on coastal areas for which there is some reason to believe may have warmed more than their surroundings.

You keep attacking "extrapolation" saying it creates bias and that GISS "shouldn't extrapolate as far." This is at odds with basic statistics. Extrapolation doesn't create bias. What creates bias is if you use thermometers for which there is a physical reason to believe they are warmer than their surroundings. You have not made such an argument. The extrapolation of warmth across the UK in November 2010 doesn't create bias because it's just as likely that in other months cold will be extrapolated.

Saying that GISS should be cross-checked with the satellites means that GISS is no longer an independent source of data. You can cross check the spatial pattern of temperatures but not the amplitude. An objective comparison shows that GISS sometimes extrapolates too warm and sometimes extrapolates too cold.

It's actually sort of funny you think you can come along and tell scientists how they need to cross-check GISS. You don't think anybody else noticed that sometimes the extrapolations are going to be incorrect? You don't think anybody else bothered to do the statistical studies to see what, if any, the effect of this would be?

Which areas were extrapolated to cool?

[skierinvermont]

Which areas were extrapolated to cool?

The most glaring is around the Black Sea and westward towards Greece and the NE Mediterranean ... this area RSS has up to 6C anomalies and lots of >4C. GISS runs about 2C cooler across the whole area.

There is also an area of negative anomalies on GISS between Brazil and Africa which RSS has as positive anomalies.

There's an area of the Antarctic coastline and coastal waters SE of Africa that are blue on GISS but red on RSS.

Also most of the tropical pacific is cooler on GISS although this is somewhat expected due to the La Nina.

There's more too. The most glaring is the black sea/greece area.

Also don't forget in many of these areas you can subtract .2-1C from the GISS anomalies because it is using a colder baseline which makes the anomalies appear larger.

[nzucker]

Again you continue to fail to understand the mathematical effect of extrapolation. Had one of those cool spots fallen on top of a thermometer GISS uses to extrapolate in the arctic, then GISS would have been vastly too cool. It all balances out. It's very basic really.

And this did in fact happen in numerous areas in November 2010, and every other month of GISS data. Some areas were extrapolated too cool. The most glaring is the area around the Black Sea where both NCEP and RSS place anomalies >4C all the way westward to Greece, where GISS has anomalies 1-2 and 2-4C. You seem to think you have discovered something by noticing all these areas where GISS looks to have extrapolated too warm.. when in fact all you are doing is showing your bias in failing to observe the areas in which it extrapolated far too cold.

Unless you can demonstrate a physical basis for why the thermometers GISS uses would be persistently warm biased relative to their surroundings you have no argument. You can form an accurate and fairly precise index of global temperatures using no more than 100 thermometers globally and extrapolating 2,000+km from each of them. Some extrapolations would be too warm, some too cold, but month to month, and especially year to year and decade to decade, it all balances out. GISS and HadCRUT have far far more thermometers than they need. I can select break the globe up into 100 boxes and use just 1 thermometer per box and I will come up with the exact same 100-yr warming trend as GISS and HadCRUT. Such studies have in fact been done and do in fact show the same trend as GISS and HadCRUT over the 20th century.

And many of the extrapolations would have been far FAR more horrendous than the extrapolation over the UK in November 2010 that you keep harping on as invalidating GISS and saying should have been crosschecked. And yet somehow SOMEHOW it ends up with the exact same result as GISS and HadCRUT even using less than 5% the number of thermometers that they use and extrapolating much farther than either of them.

BTW there is some basis for making the argument that GISS uses thermometers which are persistently warmer than their surroundings.. but you have failed to make that argument at all. It is possible that GISS extrapolates somewhat too much warmth because some of the thermometers GISS uses are located on coastal areas for which there is some reason to believe may have warmed more than their surroundings.

You keep attacking "extrapolation" saying it creates bias and that GISS "shouldn't extrapolate as far." This is at odds with basic statistics. Extrapolation doesn't create bias. What creates bias is if you use thermometers for which there is a physical reason to believe they are warmer than their surroundings. You have not made such an argument. The extrapolation of warmth across the UK in November 2010 doesn't create bias because it's just as likely that in other months cold will be extrapolated.

Saying that GISS should be cross-checked with the satellites means that GISS is no longer an independent source of data. You can cross check the spatial pattern of temperatures but not the amplitude. An objective comparison shows that GISS sometimes extrapolates too warm and sometimes extrapolates too cold.

It's actually sort of funny you think you can come along and tell scientists how they need to cross-check GISS. You don't think anybody else noticed that sometimes the extrapolations are going to be incorrect? You don't think anybody else bothered to do the statistical studies to see what, if any, the effect of this would be?

I don't have to worry about discussing areas that GISS extrapolated/measured as too cold, because they've obviously been overwhelmed by the bias towards warmth in the GISS dataset compared to the satellites in the last 5 years, even accounting for the difference in base period. For example, GISS came in at .73C for November 2010 while the satellites came in around .3C; when we add .26C to account for the difference in base period, GISS is still showing the world to be .2C warmer than the lower troposphere readings. This is a substantial difference and also flies in the face of the idea that the lower troposphere should be warming more than the surface, not less. Obviously there are going to be some areas where GISS is colder, like the tropical Pacific (ENSO) regions, since the satellites have a lag here and aren't going to directly measure the fairly rapid decline in SSTs during the past few months. I'm just ignoring these areas because obviously the bias is towards warmth, not cold, so we have to figure out where it's coming from; I'd guess extrapolation is part of the reason for the difference.

I am making the argument that GISS thermometers are warmer than the surroundings...I think that's pretty implicit in what I've said about the extrapolations being partly incorrect. I agree that the coastal positioning may be one problem (read this argument before), and I also think there may be some siting issues if what I've seen on Watts has any basis in reality. It does seem that some of the stations are poorly placed in terms of measuring regions that are predominantly rural. Part of this is simple necessity; weather stations have to be in more populated areas to serve a purpose, to be maintained, to collect data easily, etc. It's very difficult to create a network of stations sited in complete wilderness areas of the Arctic, even though northern Canada is probably 99% wilderness. I wouldn't be surprised if having stations near towns, near airports/air strips, etc creates some warm bias, although obviously not on the level of the major US cities' warm bias. I'm pretty sensitive to siting issues/UHI because of where I live and the great differences in temperature I've noted between southern Westchester and just 10 miles north of me in the forested rural areas, as well as in the nature of central Jersey versus the first ring of suburbs...seems like the heat always goes off or AC comes on in the car when you cross into that first ring. With GISS this would be a more minor effect, of course, but could still be relevant. I also think that extrapolation has just missed some areas of cold in certain months; since most of the Arctic is warm, and that's where most of the extrapolations are taking place, it's easy to understand how the whole arctic could be filled in with warmth. A perfect example is the small pool of near normal temperatures RSS measured around the Yukon despite being surrounded by torching values.

I don't think it's necessarily bad to cross-check extrapolations. If there is a large difference between UAH/RSS and GISS, perhaps those areas should just be left blank as unknown, like Hadley. It seems highly suspicious to show temperatures 3-4C above average when a satellite measurement of the same area shows it about .5-1C above average; I've seen this happen with several cases in GISS and don't understand why it can't just be blacked out. I do think there's an AGW bias in NASA, since it's run by James Hansen who has made personal predictions about how much the Earth will warm, which haven't been verifying, so he may have something invested by showing more values. Not exactly hard to imagine seeing the corruption and indiscretion in 21st century politics.

[BethesdaWX]

The most glaring is around the Black Sea and westward towards Greece and the NE Mediterranean ... this area RSS has up to 6C anomalies and lots of >4C. GISS runs about 2C cooler across the whole area.

There is also an area of negative anomalies on GISS between Brazil and Africa which RSS has as positive anomalies.

There's an area of the Antarctic coastline and coastal waters SE of Africa that are blue on GISS but red on RSS.

Also most of the tropical pacific is cooler on GISS although this is somewhat expected due to the La Nina.

There's more too. The most glaring is the black sea/greece area.

Also don't forget in many of these areas you can subtract .2-1C from the GISS anomalies because it is using a colder baseline which makes the anomalies appear larger.

Thats True. However, where the warmth is residing, those hareas have been extrapolated everywhere no data exists, as well as an expansive mode.

It'd be great if the billions of taxpayer dollars that are flowing into GISS could somehow be used to improve reolution.

[skierinvermont]

I don't have to worry about discussing areas that GISS extrapolated/measured as too cold, because they've obviously been overwhelmed by the bias towards warmth in the GISS dataset compared to the satellites in the last 5 years, even accounting for the difference in base period. For example, GISS came in at .73C for November 2010 while the satellites came in around .3C; when we add .26C to account for the difference in base period, GISS is still showing the world to be .2C warmer than the lower troposphere readings. This is a substantial difference and also flies in the face of the idea that the lower troposphere should be warming more than the surface, not less. Obviously there are going to be some areas where GISS is colder, like the tropical Pacific (ENSO) regions, since the satellites have a lag here and aren't going to directly measure the fairly rapid decline in SSTs during the past few months. I'm just ignoring these areas because obviously the bias is towards warmth, not cold, so we have to figure out where it's coming from; I'd guess extrapolation is part of the reason for the difference.

So basically you are saying that GISS can only be correct if it shows the same or lower monthly anomalies (base period adjusted of course) as RSS. This was the point I made in the last post, that makes GISS entirely redundant. The difference between GISS isn't due to the process of extrapolation. It's due to the fact that the thermometers on the earth's surface are warming faster than the LT. This is demonstrated by the fact that if you take HadCRUT and infill in the missing areas with satellite data, it would be similar to GISS, and would show much more warming than RSS or UAH over the last 15 years. Maybe the surface is actually warming faster than the LT. Or maybe the thermometers are poorly sited and UHI is not being properly accounted for (although there is plenty of evidence showing UHI is not a problem). But whatever problem exists it is not primarily extrapolation and is mostly common to both HadCRUT and GISS, which is why your attack on extrapolation and GISS does not make any sense. If there is a problem, it is a problem with the thermometers themselves that is common to both HadCRUT and GISS.. not GISS and the process of extrapolation. If you look at RSS and UAH ONLY for the areas covered by HadCRUT .. UAH and RSS are much cooler. The only reason that UAH and RSS appear in agreement with HadCRUT is they cover more(RSS)/all(UAH) of the arctic.

Or maybe UAH and RSS are incorrect and GISS has it right (and HadCRUT is too cool because of the missing areas where we know it has warmed rapidly). After all there is a large difference between UAH and RSS and satellite data has had large corrections made it to in the past.

I am making the argument that GISS thermometers are warmer than the surroundings...I think that's pretty implicit in what I've said about the extrapolations being partly incorrect. I agree that the coastal positioning may be one problem (read this argument before), and I also think there may be some siting issues if what I've seen on Watts has any basis in reality. It does seem that some of the stations are poorly placed in terms of measuring regions that are predominantly rural. Part of this is simple necessity; weather stations have to be in more populated areas to serve a purpose, to be maintained, to collect data easily, etc. It's very difficult to create a network of stations sited in complete wilderness areas of the Arctic, even though northern Canada is probably 99% wilderness. I wouldn't be surprised if having stations near towns, near airports/air strips, etc creates some warm bias, although obviously not on the level of the major US cities' warm bias. I'm pretty sensitive to siting issues/UHI because of where I live and the great differences in temperature I've noted between southern Westchester and just 10 miles north of me in the forested rural areas, as well as in the nature of central Jersey versus the first ring of suburbs...seems like the heat always goes off or AC comes on in the car when you cross into that first ring. With GISS this would be a more minor effect, of course, but could still be relevant. I also think that extrapolation has just missed some areas of cold in certain months; since most of the Arctic is warm, and that's where most of the extrapolations are taking place, it's easy to understand how the whole arctic could be filled in with warmth. A perfect example is the small pool of near normal temperatures RSS measured around the Yukon despite being surrounded by torching values.

I don't think it's necessarily bad to cross-check extrapolations. If there is a large difference between UAH/RSS and GISS, perhaps those areas should just be left blank as unknown, like Hadley. It seems highly suspicious to show temperatures 3-4C above average when a satellite measurement of the same area shows it about .5-1C above average; I've seen this happen with several cases in GISS and don't understand why it can't just be blacked out. I do think there's an AGW bias in NASA, since it's run by James Hansen who has made personal predictions about how much the Earth will warm, which haven't been verifying, so he may have something invested by showing more values. Not exactly hard to imagine seeing the corruption and indiscretion in 21st century politics.

Maybe you should read about the UHI adjustments and the thermometer siting standards and the studies done to see if this has any effect before accusing them of failing to account for UHI. You think you and Anthony Watts are the only people that have ever noticed the UHI effect? The data is adjusted for UHI and studies have been done showing that the results are not affected by UHI.

You keep harping on the process of extrapolation when that clearly is not the problem (if there is a problem at all with the surface data). You've already agreed that HadCRUT is likely too cold because it misses areas that have warmed the fastest. That puts it nearly in agreement with GISS and out of agreement with RSS and UAH (it already was out of agreement with UAH). So you have the same problem with HadCRUT as you do with GISS - it runs warmer than the satellites when you factor in the rapid warming over the areas it doesn't cover.

Using RSS to "cross-check" GISS extrapolations doesn't make any sense because even in the areas GISS doesn't extrapolate, GISS is warming faster. So clearly it is a problem with the thermometers or with the satellites.. NOT extrapolation.

Which sholdn't come as a surprise at all to anybody that understands the mathematical effect of extrapolation.. sometimes you extrapolate too warm sometimes too cold and it balances out. As I said before you can make an accurate index of global temperatures using just 100 thermometers (instead of the 1000s that GISS uses) and extrapolating 2000+ km from each of them.

[tacoman25]

No it's not based on UAH's starting point ... it's based on a linear regression. UAH is out of wack with the other 3. Which is strange since RSS and UAH are basically the same raw data.

The linear regression relates to the starting point though, doesn't it?

Regardless, UAH and RSS have matched each other in recent years better than GISS and HadCRU. It seems like the satellites had more of an issue matching each other early on.

[tacoman25]

The most glaring is around the Black Sea and westward towards Greece and the NE Mediterranean ... this area RSS has up to 6C anomalies and lots of >4C. GISS runs about 2C cooler across the whole area.

There is also an area of negative anomalies on GISS between Brazil and Africa which RSS has as positive anomalies.

There's an area of the Antarctic coastline and coastal waters SE of Africa that are blue on GISS but red on RSS.

Also most of the tropical pacific is cooler on GISS although this is somewhat expected due to the La Nina.

There's more too. The most glaring is the black sea/greece area.

Also don't forget in many of these areas you can subtract .2-1C from the GISS anomalies because it is using a colder baseline which makes the anomalies appear larger.

Funny how that works, huh?

[LakeEffectKing]

Dec. HadCrut:

+.43....which is .039 higher than Nov.....GISS had issues.

[tacoman25]

Dec. HadCrut:

+.43....which is .039 higher than Nov.....GISS had issues.

Yeah, there is no way the Arctic was responsible for that big of a difference in November.

[The_Global_Warmer]

So where is this year going to finish?

[BethesdaWX]

Wow....HUGE drop! Biggest drop (change) in a 9 day period for DEC in the entire satellite era years

[BethesdaWX]

DEC Probably finishes near 0.2C....we probably drop to 0.0 in maybe 50-55 days IMO, the fall -0.1 to -0.2C below avg by Early/Mid spring.