For Crickham- Critique of GISS Urbanization Adjustments

[CrusaderFrank]

Some pertinent Q&A from GISS FAQs at http://data.giss.nasa.gov/gistemp/FAQ.html. Pay special heed to the very last Q/A:

Q. Why can't we use just raw data?
A. Just averaging the raw data would give results that are highly dependent on the particular locations (latitude and elevation) and reporting periods of the actual weather stations; such results would mostly reflect those accidental circumstances rather than yield meaningful information about our climate.

Q. Can you illustrate the above with a simple example?
A. Assume, e.g., that a station at the bottom of a mountain sent in reports continuously starting in 1880 and assume that a station was built near the top of that mountain and started reporting in 1900. Since those new temperatures are much lower than the temperatures from the station in the valley, averaging the two temperature series would create a substantial temperature drop starting in 1900.

Q. How can we combine the data of the two stations above in a meaningful way?
A. What may be done before combining those data is to increase the new data or lower the old ones until the two series seem consistent. How much we have to adjust these data may be estimated by comparing the time period with reports from both stations: After the offset, the averages over the common period should be equal. (This is the basis for the GISS method). As new data become available, the offset determined using that method may change. This explains why additional recent data can impact also much earlier data in any regional or global time series.

Another approach is to replace both series by their anomalies with respect to a fixed base period. This is the method used by the University of East Anglia's Climatic Research Unit (CRU) in the UK. The disadvantage is that stations that did not report during that whole base period cannot be used.

More mathematically complex methods are used by NOAA National Climatic Data Center (NOAA/NCDC) and the Berkeley Earth Project, but the resulting differences are small.

Q. Do the raw data ever change?
A. The raw data always stays the same, except for occasional reported corrections or replacements of preliminary data from one source by reports obtained later from a more trusted source.

Q. Does GISS deal directly with raw (observed) data?
A. No. GISS has neither the personnel nor the funding to visit weather stations or deal directly with data observations from weather stations. GISS relies on data collected by other organizations, specifically, NOAA/NCDC's Global Historical Climatology Network (GHCN) v3 adjusted monthly mean data as augmented by Antarctic data collated by UK Scientific Committee on Antarctic Research (SCAR) and also NOAA/NCDC's Extended Reconstructed Sea Surface Temperature (ERSST) v3b data.

Q. Why use the adjusted rather than the "raw" data?
A. GISS uses temperature data for long-term climate studies. For station data to be useful for such studies, it is essential that the time series of observations are consistent, and that any non-climatic temperature jumps, introduced by station moves or equipment updates, are corrected for. In adjusted data the effect of such non-climatic influences is eliminated whenever possible. Originally, only documented cases were adjusted, however the current procedure used by NOAA/NCDC applies an automated system that uses systematic comparisons with neighboring stations to deal with undocumented instances of artificial changes. The processes and evaluation of these procedures are described in numerous publications — for instance, Menne et al., 2010 and Venema et al., 2012 — and at the NOAA/NCDC website.

Q. Does GISS do any data checking and alterations?
A. Yes. GISS applies semi-automatic quality control routines listing records that look unrealistic. After manual inspection, those data are either kept or rejected. GISS does make an adjustment to deal with potential artifacts associated with urban heat islands, whereby the long-term regional trend derived from rural stations is used instead of the trends from urban centers in the analysis.

Q. Does NASA/GISS skew the global temperature trends to better match climate models?
A. No.

Q. How accurate are the GISS results (tables, graphs)?
A. The GISS results are really estimates based on the available data. Accurate error estimates are hard to obtain. However, it is likely that the largest contribution to the margin of error is given by the temporal and spatial data gaps. That particular margin was estimated as follows: All computations were first made replacing the observed data by complete model data. Then the calculations were repeated after discarding model data where the corresponding observations were missing. Comparisons of the two results were used to obtain an estimate for that margin of error. Assuming that the other inaccuracies might about double that estimate yielded the error bars for global annual means drawn in this graph, i.e., for recent years the error bar for global annual means is about ±0.05°C, for years around 1900 it is about ±0.1°C. The error bars are about twice as big for seasonal means and three times as big for monthly means. Error bars for regional means vary wildly depending on the station density in that region. Error estimates related to homogenization or other factors have been assessed by CRU and the Hadley Centre (among others).

Q. Can I do my own analysis?
A. Yes. The full code and instructions for the GISTEMP analysis are available here, though it can be a little tricky to get to work. There is a more user-friendly independent replication of the GISTEMP procedure that has been created by Nick Barnes and colleagues at the clearclimatecode website. This matches the original GISTEMP code to 2 significant figures.

Q. Where can I find absolute temperatures on the GISS website rather than temperature anomalies?
A. Nowhere. The reasons for that are explained here.

Q. Why are the US mean temperatures in your 1999 paper so different from later figures?
A. In the Hansen et al. (1999) paper the GISS analysis was based on GHCN data alone; in the meantime, the group working at NOAA/NCDC had taken a closer look at the US data, an investigation that resulted in substantial modifications compensating for station moves, procedural changes, etc. These corrected data were made available as "adjusted USHCN" data. The adjustments and their effects are described here with a graph showing the effect of each of the 5 individual adjustments here. These adjustments caused an increase of about 0.5°C in the US mean for the period from 1900 to 1990. They had no significant impact on the global mean. About half of that increase was due to information obtained about station moves (mostly from cities to airports where conditions were generally cooler), the other half from changes in the time of observation (mostly as a consequence of a concerted effort to transition to a uniform time of observation for a whole network of stations). After 1999, GISS replaced the unadjusted USHCN reports by the adjusted reports, and reported on the differences this made in Hansen et al. (2001)

LOL.

That was funny.

It likes reading from Bernie Madoff's accountant

 

[Kosh]

I recommend the readers actually read some of the articles for themselves.

Distancing yourself from weedwhackergate already? Good choice.

For intelligent discussion of such issues, which often means pointing out how badly Goddard or McIntyre screwed it up, Moyhu/Nick Stokes is a good read.

moyhu

Nick Stokes is also one of the few sane commenters at WUWT. He takes constant personal abuse from Watts and the peanut gallery, but always stays calm and just talks only about the science. Meaning Watts will eventually ban him. It's amazing he's lasted this long.

Like the Y2K fiasco that took an amateur to find after being on the books for seven years.

The "fiasco" that changed the global average by <0.001 C? Yeah, real game changer, that. But since it's about the only thing that Steve McIntyre has ever gotten correct, I guess it has to be highlighted.

While the correlation between atmospheric increases in CO2 and earth's temperatures is poor (r2=0.44), it is much better for solar irradiance and solar activity (r2=>70 -- The higher the rs value the greater the correlation). It has long been known that solar irradiance by itself does not provide enough energy to cause the warming on earth experienced in the twentieth century. However, when combined with the type of solar irradiance that is emitted during high periods of solar activity every 11 and 22 years (the solar cycle), there is a poorly understood, but good correlation. Solar flares, coronal mass ejections and other solar activity reach a maximum during the peak of each solar cycle and somehow influence ocean temperatures and therefore climate. One of the leading theories on this interaction is the interaction between solar activity and incoming cosmic radiation on cloud formation.

More proof that AGW is a religion not based on science.

 

[IanC]

Like the Y2K fiasco that took an amateur to find after being on the books for seven years.

The "fiasco" that changed the global average by <0.001 C? Yeah, real game changer, that. But since it's about the only thing that Steve McIntyre has ever gotten correct, I guess it has to be highlighted.[/QUOTE]

It only affected US temps. To the tune of 0.15C on average. Hardly negligible.

 

[CrusaderFrank]

Earth's temperature has not risen significantly since 1998 and has cooled by 0.5oC since early 2007. Even the United Nations has quietly admitted this. This is completely contrary to the CO2 caused global warming theory, which states that the earth's temperature should be quickly rising because atmospheric CO2 is rising quickly. The UN and those who support the CO2 warming theory claim that the cooling is just a temporary glitch and earth's temperature will began to rise again in a year or two. However, as explained, a majority of scientists now believe that we are in for a 15 to 35 year cooling cycle that has nothing to do with CO2 and everything to do with solar activity and temperature oscillations of the oceans.

When you adjust the temperature and add in the warming eaten by the Deep Pacific Ocean (in a methodology completely contrary to that described by Crick) you the AGW as projected by the models

 

[asterism]

Q. Can I do my own analysis?
A. Yes. The full code and instructions for the GISTEMP analysis are available here, though it can be a little tricky to get to work. There is a more user-friendly independent replication of the GISTEMP procedure that has been created by Nick Barnes and colleagues at the clearclimatecode website. This matches the original GISTEMP code to 2 significant figures.

Actually, no.

Q. Where can I find absolute temperatures on the GISS website rather than temperature anomalies?
A. Nowhere. The reasons for that are explained here.

Notice how they don't provide the actual raw data.

Apparently they are the only ones smart enough to handle such a thing. It's funny how in astronomy raw data is immediately published before any papers are written about it and anyone can do their own analysis. Amateurs are even invited to submit their own data to contribute to the research. But apparently climatology is more complicated than astronomy.

 

[asterism]

That issue is a fine illustration of how assuming a vast conspiracy almost always makes the assumer end up looking stupid.

In 2013, at a weather station in Luling, Texas, a lawnmower or weed whacker damaged a data cable, causing temperature readings to suddenly plunge.

The processing algorithms notice if any station suddenly spikes very high or very low compared to neighboring stations, and corrects for such obviously bad data.

And that would be the sum total of the "conspiracy" here, a damaged cable. Goddard and pals are getting increasingly desperate and crazy in regards to what they define as a conspiracy. Ian, if you keep trusting them, you'll keep getting embarrassed.

How does a damaged data cable cause temperature readings to "plunge?" I don't think you understand how this works. A sensor records a temperature and an apparatus communicates that reading. If the data cable is sufficiently damaged the reading is not communicated. It's a binary phenomenon, either the reading is sent and received or it isn't. The reading doesn't "plunge."

 

[asterism]

Like the Y2K fiasco that took an amateur to find after being on the books for seven years.

The "fiasco" that changed the global average by <0.001 C? Yeah, real game changer, that. But since it's about the only thing that Steve McIntyre has ever gotten correct, I guess it has to be highlighted.

It only affected US temps. To the tune of 0.15C on average. Hardly negligible.

Do you see what he did there? He applied the US temperature error globally by simply dividing the anomaly by the total affected area to get a resulting temperature impact. This is why climatologists don't have very good data integrity, they don't understand the data they are manipulating.

 

[CrusaderFrank]

Some pertinent Q&A from GISS FAQs at http://data.giss.nasa.gov/gistemp/FAQ.html. Pay special heed to the very last Q/A:

Q. Why can't we use just raw data?
A. Just averaging the raw data would give results that are highly dependent on the particular locations (latitude and elevation) and reporting periods of the actual weather stations; such results would mostly reflect those accidental circumstances rather than yield meaningful information about our climate.

Q. Can you illustrate the above with a simple example?
A. Assume, e.g., that a station at the bottom of a mountain sent in reports continuously starting in 1880 and assume that a station was built near the top of that mountain and started reporting in 1900. Since those new temperatures are much lower than the temperatures from the station in the valley, averaging the two temperature series would create a substantial temperature drop starting in 1900.

Q. How can we combine the data of the two stations above in a meaningful way?
A. What may be done before combining those data is to increase the new data or lower the old ones until the two series seem consistent. How much we have to adjust these data may be estimated by comparing the time period with reports from both stations: After the offset, the averages over the common period should be equal. (This is the basis for the GISS method). As new data become available, the offset determined using that method may change. This explains why additional recent data can impact also much earlier data in any regional or global time series.

Another approach is to replace both series by their anomalies with respect to a fixed base period. This is the method used by the University of East Anglia's Climatic Research Unit (CRU) in the UK. The disadvantage is that stations that did not report during that whole base period cannot be used.

More mathematically complex methods are used by NOAA National Climatic Data Center (NOAA/NCDC) and the Berkeley Earth Project, but the resulting differences are small.

Q. Do the raw data ever change?
A. The raw data always stays the same, except for occasional reported corrections or replacements of preliminary data from one source by reports obtained later from a more trusted source.

Q. Does GISS deal directly with raw (observed) data?
A. No. GISS has neither the personnel nor the funding to visit weather stations or deal directly with data observations from weather stations. GISS relies on data collected by other organizations, specifically, NOAA/NCDC's Global Historical Climatology Network (GHCN) v3 adjusted monthly mean data as augmented by Antarctic data collated by UK Scientific Committee on Antarctic Research (SCAR) and also NOAA/NCDC's Extended Reconstructed Sea Surface Temperature (ERSST) v3b data.

Q. Why use the adjusted rather than the "raw" data?
A. GISS uses temperature data for long-term climate studies. For station data to be useful for such studies, it is essential that the time series of observations are consistent, and that any non-climatic temperature jumps, introduced by station moves or equipment updates, are corrected for. In adjusted data the effect of such non-climatic influences is eliminated whenever possible. Originally, only documented cases were adjusted, however the current procedure used by NOAA/NCDC applies an automated system that uses systematic comparisons with neighboring stations to deal with undocumented instances of artificial changes. The processes and evaluation of these procedures are described in numerous publications — for instance, Menne et al., 2010 and Venema et al., 2012 — and at the NOAA/NCDC website.

Q. Does GISS do any data checking and alterations?
A. Yes. GISS applies semi-automatic quality control routines listing records that look unrealistic. After manual inspection, those data are either kept or rejected. GISS does make an adjustment to deal with potential artifacts associated with urban heat islands, whereby the long-term regional trend derived from rural stations is used instead of the trends from urban centers in the analysis.

Q. Does NASA/GISS skew the global temperature trends to better match climate models?
A. No.

Q. How accurate are the GISS results (tables, graphs)?
A. The GISS results are really estimates based on the available data. Accurate error estimates are hard to obtain. However, it is likely that the largest contribution to the margin of error is given by the temporal and spatial data gaps. That particular margin was estimated as follows: All computations were first made replacing the observed data by complete model data. Then the calculations were repeated after discarding model data where the corresponding observations were missing. Comparisons of the two results were used to obtain an estimate for that margin of error. Assuming that the other inaccuracies might about double that estimate yielded the error bars for global annual means drawn in this graph, i.e., for recent years the error bar for global annual means is about ±0.05°C, for years around 1900 it is about ±0.1°C. The error bars are about twice as big for seasonal means and three times as big for monthly means. Error bars for regional means vary wildly depending on the station density in that region. Error estimates related to homogenization or other factors have been assessed by CRU and the Hadley Centre (among others).

Q. Can I do my own analysis?
A. Yes. The full code and instructions for the GISTEMP analysis are available here, though it can be a little tricky to get to work. There is a more user-friendly independent replication of the GISTEMP procedure that has been created by Nick Barnes and colleagues at the clearclimatecode website. This matches the original GISTEMP code to 2 significant figures.

Q. Where can I find absolute temperatures on the GISS website rather than temperature anomalies?
A. Nowhere. The reasons for that are explained here.

Q. Why are the US mean temperatures in your 1999 paper so different from later figures?
A. In the Hansen et al. (1999) paper the GISS analysis was based on GHCN data alone; in the meantime, the group working at NOAA/NCDC had taken a closer look at the US data, an investigation that resulted in substantial modifications compensating for station moves, procedural changes, etc. These corrected data were made available as "adjusted USHCN" data. The adjustments and their effects are described here with a graph showing the effect of each of the 5 individual adjustments here. These adjustments caused an increase of about 0.5°C in the US mean for the period from 1900 to 1990. They had no significant impact on the global mean. About half of that increase was due to information obtained about station moves (mostly from cities to airports where conditions were generally cooler), the other half from changes in the time of observation (mostly as a consequence of a concerted effort to transition to a uniform time of observation for a whole network of stations). After 1999, GISS replaced the unadjusted USHCN reports by the adjusted reports, and reported on the differences this made in Hansen et al. (2001)

But it's OK to add the "WARMING" from the Deep Pacific Ocean to account for the lack of recent Warming.

Hmmmmkay

 

[mamooth]

How does a damaged data cable cause temperature readings to "plunge?" I don't think you understand how this works.

I don't think you know what a thermistor is. You assume pure digital for no good reason.

 

[Kosh]

Just to annoy the narrow minded AGW cult that hate real science:

....snip.....

And here is the real kicker, &#8220;Zombie weather stations&#8221; exist in the USHCN final data set that are still generating data, even though they have been closed.

The scientific method is at work on the USHCN temperature data set | Watts Up With That?

 

[mamooth]

Kosh, demonstrate for us that you're not a brainless parrot by providing a good summary of your link in your own words.

If you can't provide even that minimum, there's no reason to talk to you. After all, only a flaming hypocrite of the sleaziest type would demand that others spend time refuting a cut-and-paste that he can't explain himself.

You don't have to, of course. But if you don't, I can simply provide a counter-link and declare I win. After all, it's your tactic, so you can't complain. Though you still will, because it's what you do. Here's the counter-link that refutes all the nonsense.

moyhu

 

[Kosh]

Kosh, demonstrate for us that you're not a brainless parrot by providing a good summary of your link in your own words.

If you can't provide even that minimum, there's no reason to talk to you. After all, only a flaming hypocrite of the sleaziest type would demand that others spend time refuting a cut-and-paste that he doesn't understand at all.

You don't have to, of course. But if you don't, I can simply provide a counter-link and declare I win. After all, that's you tactic, so you can't complain. Though you still will. Here's the counter-link that refutes all the nonsense.

moyhu

More ironic comments from the AGW cult!

This graph is self explanatory and defeats all the AGW scripture being posted on this board.

Oh wait now I am starting to sound like one of the AGW cult members.

 

[mamooth]

I've explained the illogical nature of your use of that graph before. Your big bonehead error is that you're assuming a single point at Vostok represents the whole world.

That's called a cherrypicking fallacy. You depend almost entirely on cherrypicking fallacies. Since your conclusion are based on an obvious fallacy, your conclusions are invalid.

Now, would you care to offer a counterargument as to why your cherrypicking fallacy doesn't invalidate your claims? That's what a rational and honest person would do. A cowardly liar, alas, would hurl insults and avoid such a discussion.

 

[Kosh]

I've explained the illogical nature of your use of that graph before. Your big bonehead error is that you're assuming a single point at Vostok represents the whole world.

That's called a cherrypicking fallacy. You depend almost entirely on cherrypicking fallacies. Since your conclusion are based on an obvious fallacy, your conclusions are invalid.

Now, would you care to offer a counterargument as to why your cherrypicking fallacy doesn't invalidate your claims? That's what a rational and honest person would do. A cowardly liar, alas, would hurl insults and avoid such a discussion.

More ironic comments form the AGW cult.

The chart trumps the whole AGW claims and they just can not handle it.

But then again what do I expect from those that believe hockey stick are a part of science.

The ice core samples prove that the temperature on EARTH was much hotter than it is now.

However:

This is self explanatory and defats the AGW claims once again. If I have to explain this graph that mean it would to explain it to the AGW cult members.

 

[CrusaderFrank]

I've explained the illogical nature of your use of that graph before. Your big bonehead error is that you're assuming a single point at Vostok represents the whole world.

That's called a cherrypicking fallacy. You depend almost entirely on cherrypicking fallacies. Since your conclusion are based on an obvious fallacy, your conclusions are invalid.

Now, would you care to offer a counterargument as to why your cherrypicking fallacy doesn't invalidate your claims? That's what a rational and honest person would do. A cowardly liar, alas, would hurl insults and avoid such a discussion.

Ahhhh, look at the Culty yelling DENIER! at the mean old Vostock Ice Cores

 

[asterism]

I've explained the illogical nature of your use of that graph before. Your big bonehead error is that you're assuming a single point at Vostok represents the whole world.

That's called a cherrypicking fallacy. You depend almost entirely on cherrypicking fallacies. Since your conclusion are based on an obvious fallacy, your conclusions are invalid.

Now, would you care to offer a counterargument as to why your cherrypicking fallacy doesn't invalidate your claims? That's what a rational and honest person would do. A cowardly liar, alas, would hurl insults and avoid such a discussion.

Now you're talkin'! Vostok is not the entire planet. What are the other prevailing sources for ancient CO2 concentrations?

 

[IanC]

The "fiasco" that changed the global average by <0.001 C? Yeah, real game changer, that. But since it's about the only thing that Steve McIntyre has ever gotten correct, I guess it has to be highlighted.

It only affected US temps. To the tune of 0.15C on average. Hardly negligible.

Do you see what he did there? He applied the US temperature error globally by simply dividing the anomaly by the total affected area to get a resulting temperature impact. This is why climatologists don't have very good data integrity, they don't understand the data they are manipulating.

actually, that is not the most important point. the warmers handwave away any mistake as unimportant, they say they still got the 'right answer' even if there were mistakes. they dont seem to understand that mistakes point to an underlying problem. mistakes are important even if they still give an answer that is 'consistent with'. and of course, mistakes make a mockery of the estimated error bars and their claimed (un)certainty.

 

[Crick]

What underlying problem would that be Ian?

1) Is the world NOT warming up?
2) Is the greenhouse effect a SHAM?
3) Have humans NOT increased CO2 in the atmosphere by 120 ppm
4) Does CO2 NOT absorb infrared at the frequencies at which the Earth radiates it and at which water vapor does NOT absorb it?
5) Do increasing temperatures NOT cause CO2 to come out of solution in the world ocean?

Which is it Ian? WHAT is this "underlying problem"?

 

[asterism]

What underlying problem would that be Ian?

1) Is the world NOT warming up?
2) Is the greenhouse effect a SHAM?
3) Have humans NOT increased CO2 in the atmosphere by 120 ppm
4) Does CO2 NOT absorb infrared at the frequencies at which the Earth radiates it and at which water vapor does NOT absorb it?
5) Do increasing temperatures NOT cause CO2 to come out of solution in the world ocean?

Which is it Ian? WHAT is this "underlying problem"?

I won't answer for Ian, but I see an underlying problem in the direct correlation the AGW theory has with global average temperature and CO2.

If massive increases in CO2 cause increases in warming, why hasn't there been any global warming recently?

 

[Crick]

Did you just think of that? Wow! Amazing no one else caught that.