Moderated Global Warming Discussion

[Furcifer]

frankly I don't care if your jaw drops, please state where NOAA defines 20th century includes either dates prior to 1st Jan 1900 or after 31st Dec 1999 (OK, being pedantic, the dates should be one year later!), just because they display graphs with their full range of data does not mean that they use data outside of the bounds of the 20th century to form a 20th century average. This detail is something you appear to have made up.

The closest description I have found so far is here:
http://www.ncdc.noaa.gov/cmb-faq/anomalies.php

I suggest you read the paper cited instead of trying to interpret things. You're confusing the anomaly analysis with the averages and getting the dates messed up. Again, please read the paper, it clearly indicates how the average was calculated. NOAA has open access to the data so you can even download the girds themselves.

 

[Furcifer]

Edited for moderated thread.

Replying to this modbox in thread will be off topic  Posted By: Cuddles

I stated quite clearly what the situaton is:

• The US temperatures are regional temperatures.
• The global temperatures are ... global !

Of course the global temperatures are calculated from all of the regional temperatures from areting the world (including the US).

But you seem to fall short of understanding the global average is only as good as the sum of its parts.

So whether these regional temperatures do or do not change the contribute to that average remains to be seen.

That isn't how math works I'm afraid.

I do not think that you know the climate science.

Clearly, I don't think you understand either. At least I read the papers

Absolute temperatures do not matter much.

Oreaaly? how "much" then? Express this in exact scientific terms please.

It is temperature anomalies that are used. The calculation of global temperatures is designed to minimize the effect of out-lier measurements such as the ones mentioned in the Arctic. For these reasons, it is extremely naive to think that a big number in any reported bias will result in a big change in global temperature anomalies.

Huge bias actually, huge. The effect of which remains to be seen.

The big point is that these will have an even smaller impact on the trends in the temperature anomalies.

Evidence?

The scientific evidence is that the global temperatures from surface stations match the global temperatures from satellites (but usually stated as temperature anomalies).

Evidence?

More regional stuff and no analysis on the impact on global temperatures.

So basically the future result of these papers will be that the biases in these measurements will be compensated for and we will get more reliable readings from these surface stations.

This is good science.

Hardly, none of which directly address the recently discovered bias in measurements. This is just more hand waving.

 

[Pixel42]

That's precipitation

*sigh*

http://www.ncdc.noaa.gov/oa/climate/research/2007/500mbexp.html#ytdhist

The anomaly value histograms show the departure in either temperature /B] or precipitation for a given month from the 20th century (1901-2000) average for that month

Please, read the paper it's taken from and not some unrelated webpage.

The only quote you've supplied that uses the phrase "20th century average" was taken from the NOAA website, not a paper.

The link I gave is the only place I can find where the website specifies the date range meant by "20th century average", and I'm frankly surprised that they bothered to do so at all, even on a definitions page. Until now I would have taken for granted that anyone knowledgable enough to be reading the website at all would know what "20th century average" means without having to have it spelled out for them.

"20th century average" means the average from 1901-2000 in every paper, website, and laboratory on the planet. Anyone who would imagine for a moment that NOAA, or any scientist or scientific organisation, would make up their own unique definition for the phrase has no idea at all how science works.

 

[Mikemcc]

I suggest you read the paper cited instead of trying to interpret things. You're confusing the anomaly analysis with the averages and getting the dates messed up. Again, please read the paper, it clearly indicates how the average was calculated. NOAA has open access to the data so you can even download the girds themselves.

Read my lips - no it doesn't. It does not even mention the phrase. Pixel42 has already tracked down and posted the definition of the phrase. It's not the same as the one that you are alone in using.

 

[Mikemcc]

No, not for that data set. I showed you the paper, please read it.

Yes, it's what it says it is, 0.5C over the 20th Century Average. It's not very much in that 130 year period considering the average is what, 15C or 16C?




That's precipitation. Please, read the paper it's taken from and not some unrelated webpage. In some of the averages they use the truncated period, and in some they don't.

You are clearly reading a different paper to the rest of us.

 

[Reality Check]

But you seem to fall short of understanding the global average is only as good as the sum of its parts.

You would be wrong - I understand there is not such thing as a 'global average'. Global temperatures are not averages. They are calculated in such a way to minimize many problems (including biases) with surface station data.

That isn't how math works I'm afraid.

What math? (and why are you afraid of it ?).
I do hope that you do not think that global temperatures are just calculated by averaging over surface station readings. There is a large amount of processing, largely designed to reduce the influence of bad data from the stations. See the end of this post.

Clearly, I don't think you understand either. At least I read the papers.

Wrong: I read the papers.

Oreaaly? how "much" then? Express this in exact scientific terms please.

"Much" would be zero: Global temperature calculations totally ignore absolute temperatures.

Huge bias actually, huge. The effect of which remains to be seen.

Huge bias for a small set of stations. The effect of which remains to be seen.

Evidence?

The science stated in

• Analysis of the impacts of station exposure on the U.S. Historical Climatology Network temperatures and temperature trends
• Erroneous Arctic Temperature Trends in the ERA-40 Reanalysis: A Closer Look
• Atmospheric temperature measurements biases on the Antarctic plateau

Evidence?

You need to learn to follow links and read them: See Are surface temperature records reliable? which concludes

The well-known and widely-cited reconstructions of global temperature, produced by NASA GISS, UEA CRU, and NOAA NCDC, are replicable.
Independent studies using different software, different methods, and different data sets yield very similar results.
The increase in temperatures since 1975 is a consistent feature of all reconstructions. This increase cannot be explained as an artifact of the adjustment process, the decrease in station numbers, or other non-climatological factors.

Hardly, none of which directly address the recently discovered bias in measurements. This is just more hand waving.

Still wrong. There is no hand waving. These papers state no implication of these biases on global temperatures. That is a fact.




For the education of other people and maybe you:

• Of Averages and Anomalies - Part 1A. A Primer on how to measure surface temperature change
• Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
• Of Averages & Anomalies - Part 2A. Why Surface Temperature records are more robust than we think
• Of Averages & Anomalies - Part 2B. More on why Surface Temperature records are more robust than we think

 

[Pixel42]

[

Pixel did, I don't see the relevance either. More goal post moving I presume.

For the record, here's the relevant part of the post from which Furcifer got the link for 2010 instead of 2011:

Incidentally you forgot to point out that this time last year

Apparently Furcifer is unaware that this time last year it was 2010.

 

[BenBurch]

The hand waving is by people who seem not to comprehend several centuries of learning to deal with large sets of measurements where mutual calibration and bias correction must be done.

 

[Halsu]

Clearly, I don't think you understand either. At least I read the papers

By "the paper" i assume you mean this?

http://www.ncdc.noaa.gov/sotc/global/2010/7

Nothing there that would suggest that NOAA (not NASA) has re-invented what the 20th century is. It's still 1901-2000. Years before and after do NOT affect the 20th century average in any way.

If still you think otherwise, could you point to us where exactly in the paper they say that the 20th century average spans from 1880 to 2010?

Oreaaly? how "much" then? Express this in exact scientific terms please.

That's easy to answer as far as i know: "Zero".

The measuring biases do not affect the result in any way, as long as the bias remains the same during the whole period of time. Same goes for the actual temperature values - when it comes to temperature anomalies, it's completely irrelevant for the result whether the change is from 1 to 10 degrees or from 91 to 100 degrees.

Why?

Because the global temperature anomaly graphs like the ones below show only the CHANGE of global temperatures over time, not the absolute values.

Evidence?

 

[Trakar]

Clearly it is, please read the papers cited. You'll immediately see your error. I believe the analysis on anomalies uses a truncated data set and the averages use the entire 1880-2006 period (look for the "gridded" values on the NOAA website)

If the pictures are confusing you, don't look at the pictures, read the words, slowly and carefully. "20th century average" only includes data from the 20th century.

 

[Trakar]

This is 2011.

your link, I was just trying to make sure you understood the difference.

Correct, I believe this year was the 11th warmest "on record".

this year, so far, yes, 11th warmest July on record, and 11th warmest Jan. - July period on record.

July, Jan. - July
http://www.ncdc.noaa.gov/sotc/global/2011/7#temp

July Global Land and Ocean plot 1880 - 2011
http://www.ncdc.noaa.gov/sotc/service/global/glob/201107.gif

January-July Global Land and Ocean plot 1880 - 2011
http://www.ncdc.noaa.gov/sotc/service/global/glob/201101-201107.gif

Pixel did, I don't see the relevance either. More goal post moving I presume.

It is relevent because, if the "20th Century average" was referring to an overall average temperature of the 20th century (instead of the average of 20th century July temperatures), then the number for the "20th Century average" wouldn't change month to month. But let's focus on the accurate reading and understanding of material before we move into deductive reasoning.

I believe this is correct and probably why you're confusing the applicable years and the term "20th Century Average".

In this case, your beliefs are as irrelevent as the tenuous connection they seem to hold to the realities under discussion here, your posts are listed for any and all to read, and those words evidence the actual state of affairs and understandings.

 

[Furcifer]

By "the paper" i assume you mean this?

http://www.ncdc.noaa.gov/sotc/global/2010/7

No.

Nothing there that would suggest that NOAA (not NASA) has re-invented what the 20th century is. It's still 1901-2000. Years before and after do NOT affect the 20th century average in any way.

I have no idea what you're talking about. Obviously it's based on your erroneous assumption that the NOAA webpage is the "paper".

If still you think otherwise, could you point to us where exactly in the paper they say that the 20th century average spans from 1880 to 2010?

Perhaps I was unclear, try the REFERENCES.
Please, just read the paper.

 

[Furcifer]

The only quote you've supplied that uses the phrase "20th century average" was taken from the NOAA website, not a paper.

What difference does it make what the NOAA webpage calls the data set? Read the paper they got it from and you'll know.

"20th century average" means the average from 1901-2000 in every paper, website, and laboratory on the planet. Anyone who would imagine for a moment that NOAA, or any scientist or scientific organisation, would make up their own unique definition for the phrase has no idea at all how science works.

Incorrect of course. Currently they are calculating (an assumption) the 21st Century average, it is not the average from 2000-2100. The averages were calculated before the 21st Century even finished! The same goes for the 20th Century Averages. Just because the calendar rolled onto the year 2000 why would they call something by a new name?
I can see reference to the anomalies being a truncated data set using the years from 1900-2000, but some of the data sets, namely the land and sea averages, aren't truncated.

What do you expect them to call the averages from 1880-2006? The 19th, 20th and 21st Century averages? That makes no sense. Not with so few years on either side of the 20th Century. Not to mention the mean years still fall in the 20th Century.

This is proving to be a pointless pursuit. Especially when people refuse to read the paper "Referenced".

 

[Furcifer]

The source you quote says "This value is 0.68°C (1.22°F) above the 20th century average," from which you seem to be trying to interpret "0.5^oC increase over the last 130 years" Read what is actually stated. I'm really losing faith in some in this forum, the simplest issues of basic education and fundemental science and math understanding seem to present the most confusion.

Looking at the referenced paper again I see where this may have been picked up in my peripheral, from Smith Reynolds 2005:

As with the SST, the simple averages are generally consistent with the reconstruction average. The twentieth-century warming is about 0.6°C.Because of the uncertainty estimates, the warming can only be confidently established between 0.3° and 0.9°C. Compared to the global average of Folland et al. (2001, 2001b), our average is similar over most of the analysis
period.

The more recent paper isn't redirecting from the NOAA website like it was previously. I don't know why?

 

[Furcifer]

And yet you said "the bias in temperature measurements is always positive". Why are you lying to us?

Perhaps it's because any negative "bias" is simply dropped. I happened to notice this in the Land Ocean Temperature measurements.
Summary of Recent Changes in the Land-Ocean Temperature Analyses
In the ERSST version 3 on this web page we have removed satellite data from ERSST and the merged product. The addition of satellite data caused problems for many of our users. Although, the satellite data were corrected with respect to the in situ data as described in reprint, there was a residual cold bias that remained as shown in Figure 4 there. The bias was strongest in the middle and high latitude Southern Hemisphere where in situ data are sparse. The residual bias led to a modest decrease in the global warming trend and modified global annual temperature rankings

So here it is, a negative bias in the satellite data dropped because it doesn't fit the surface measurements, which have been shown to have a positive bias.
Confirmation bias?

 

[Pixel42]

What difference does it make what the NOAA webpage calls the data set? Read the paper they got it from and you'll know.

This is the post we have been disputing:

Weather is not climate. July is typically hot. April is typically wet. January is cold.

For the year-to-date, the global combined land and ocean surface temperature of 14.31°C (57.82°F) was the 11th warmest January–July period on record. This value is 0.51°C (0.92°F) above the 20th century average.

0.5C in the last 130 years. Insignificant.

Although you don't give a link, it's clear that the quote in that post comes from the NOAA website. It does not come from any of the papers you've referenced. The last line of it is wrong in three respects:

1. 20th century average means the average from 1901-2000.

2. The rise in average global temperature since 1880 is actually about 0.9C.

3. Even 0.5C would not be insignificant in just 130 years, let alone 0.9C.

What do you expect them to call the averages from 1880-2006?

If and when they refer to such an average, I expect them to call it the average from 1880-2006. I do not expect them to call it the 20th century average, because that means the average from 1901-2000.

This is proving to be a pointless pursuit.

That's about the only thing you're getting right.

Especially when people refuse to read the paper "Referenced".

There is no paper referenced in the post under discussion, only a quote from the NOAA website.

But if you know of a paper which uses "20th century average" to mean anything other than the average from 1901-2000 by all means provide a link to it and quote where it does so. Nobody else seems able to find such a use in any of the papers you've referenced.

 

[Furcifer]

If the pictures are confusing you, don't look at the pictures, read the words, slowly and carefully. "20th century average" only includes data from the 20th century.

No it doesn't, in the referenced paper it clearly outlines the reasons and methods for taking averages depending on the data set. In some cases the records got back to 1854. In some cases the data set has been truncated, in some cases it hasn't. It's very clear and confusing at the same time, but the term 20th Century Average is not literally the years from 1901-2000. And why would it? In science we use as much data as is possible for any given experiment.

I'm finished explaining this. If you feel the 20th Century Average is only the years from 1901-2000 prove it. It's stated at the NOAA as 15.8^oC, show me where it uses those years, and only those years to calculate the average. I've shown you the papers, I've explained them, that's all I can do.

 

[Furcifer]

It is relevent because, if the "20th Century average" was referring to an overall average temperature of the 20th century (instead of the average of 20th century July temperatures), then the number for the "20th Century average" wouldn't change month to month. But let's focus on the accurate reading and understanding of material before we move into deductive reasoning.

It seems you're mistaken, nobody suggested the average wouldn't change from month to month. The notion that the average in January could be 15.8C is obscene. I'm not sure where you deduced this from.

In this case, your beliefs are as irrelevent as the tenuous connection they seem to hold to the realities under discussion here, your posts are listed for any and all to read, and those words evidence the actual state of affairs and understandings.

And a good thing they are, there's much too much pseudoscience and handwaving coming from warmists on the internet already.

 

[Furcifer]

Read my lips - no it doesn't. It does not even mention the phrase. Pixel42 has already tracked down and posted the definition of the phrase. It's not the same as the one that you are alone in using.

There's no definition for "20th Century Average". It varies as it is applied by the user. It specifically depends, at least in this case on the data set.

What's the definition for the "21st Century Average"? It's not 2000-2100 is it? It's not a specifically defined quantity, it depends on the years. The 19th Century average, which is also used in the paper isn't 1800-1899, it's 1854-1899, and it's 1880-1899. Oh and it's 1880-1909.

As I may have mentioned, the first time the 20th Century average was calculated it was 1880-1997, the second time it was 1880-2006. This was done as part of the change to the GHCN-M version 3. They don't indicate if the website will be changed to reflect this or not. As most people understand it's not meant to be literal I doubt if it will.

 

[Furcifer]

You would be wrong - I understand there is not such thing as a 'global average'. Global temperatures are not averages. They are calculated in such a way to minimize many problems (including biases) with surface station data.

They refer to it as "Global Mean Temperature" or GMT. You are correct however in so much as it's a bogus term.

I do hope that you do not think that global temperatures are just calculated by averaging over surface station readings. There is a large amount of processing, largely designed to reduce the influence of bad data from the stations. See the end of this post.

Obviously you didn't read the cited paper like you claimed.

Wrong: I read the papers.

You above statement clearly contradicts your claim.

You need to learn to follow links and read them: See Are surface temperature records reliable?

I don't read junk science websites. Journals only please.

Still wrong. There is no hand waving. These papers state no implication of these biases on global temperatures. That is a fact.

They don't need to state it, it follows logically. That's a certainty.

For the education of other people and maybe you:

• [URL="http://www.skepticalscience.com [/quote]
  /OfAveragesAndAnomalies_pt_1A.html"]Of Averages and Anomalies - Part 1A. A Primer on how to measure surface temperature change

• Of Averages and Anomalies - Part 1B. How the Surface Temperature records are built
• Of Averages & Anomalies - Part 2A. Why Surface Temperature records are more robust than we think
• Of Averages & Anomalies - Part 2B. More on why Surface Temperature records are more robust than we think

Every single link is from a junk science website. I only read the journals for information. If you can find the links to published papers please post them, I'll gladly read them. I don't let fear mongers filter my information for me.