New Peer Reviewed Study finds HadCRUT underestimated warming in recent years.

[ALiberalModerate]

From the abstract:

Incomplete global coverage is a potential source of bias in global temperature reconstructions if the unsampled regions are not uniformly distributed over the planet's surface. The widely used HadCRUT4 dataset covers on average about 84% of the globe over recent decades, with the unsampled regions being concentrated at the poles and over Africa. Three existing reconstructions with near-global coverage are examined, each suggesting that HadCRUT4 is subject to bias due to its treatment of unobserved regions.Two alternative approaches for reconstructing global temperatures are explored, one based on an optimal interpolation algorithm and the other a hybrid method incorporating additional information from the satellite temperature record. The methods are validated on the basis of their skill at reconstructing omitted sets of observations. Both methods provide superior results than excluding the unsampled regions, with the hybrid method showing particular skill around the regions where no observations are available.

Temperature trends are compared for the hybrid global temperature reconstruction and the raw HadCRUT4 data. The widely quoted trend since 1997 in the hybrid global reconstruction is two and a half times greater than the corresponding trend in the coverage-biased HadCRUT4 data. Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend. The issue is exacerbated by the strong El Niño event of 1997-1998, which also tends to suppress trends starting during those years.

More here: Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends - Cowtan - Quarterly Journal of the Royal Meteorological Society - Wiley Online Library

It was pretty obvious the world's climate was continuing to warm significantly. One only had to look at the continual loss of Arctic Sea Ice, High Altitude Glacial Retreat and so on.

 

[ttwtt78640]

I see. If the numbers are not showing the right thing then it is because they are not using the right numbers.

 

[ALiberalModerate]

I see. If the numbers are not showing the right thing then it is because they are not using the right numbers.

Well what they are saying is that we don't have much in the way of instrumental readings for the poles and some areas of Africa. This leads to a downward bias in global temps. Once they include the satellite measurements, we get a more accurate measure of global temps. Its a new study, only about a month old or so, so we will have to see whether other climatologists agree with their findings. However, if you read what they did, its a compelling argument they are making.

 

[Deuce]

I see. If the numbers are not showing the right thing then it is because they are not using the right numbers.

I'm sure you have a detailed, statistical explanation for your objection to the methodology.

 

[gslack]

Well what they are saying is that we don't have much in the way of instrumental readings for the poles and some areas of Africa. This leads to a downward bias in global temps. Once they include the satellite measurements, we get a more accurate measure of global temps. Its a new study, only about a month old or so, so we will have to see whether other climatologists agree with their findings. However, if you read what they did, its a compelling argument they are making.

Hadcrut came out a year ago, and it has made all of their wild their claims and projections obsolete. Of course they will try and save their work and attack it...

 

[ALiberalModerate]

Hadcrut came out a year ago, and it has made all of their wild their claims and projections obsolete. Of course they will try and save their work and attack it...

Hadcrut is simply one of the datasets of compiled land and sea surface temperatures used for determining average global temperatures by the Hadley center in the UK. I am assuming you are referring to the email scandal a year or 2 back, but that has nothing to do with the datasets. Moreover, the published study cited in the opening post has nothing to do with those emails either, and is simply arguing that the Hadcrut dataset was flawed due to their sparse instrument readings in parts of Africa and the poles. They show how taking Hadcrut datasets and supplementing them with satellite temperature measurements provides a better measurement of average global temperatures, and when this done, the pause in warming shown by Hadcrut is eliminated.

 

[longview]

If Hadcrut was so much in error, I wonder why it agrees with the giss data?
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
Which is said to be sourced from

sources: GHCN-v3 1880-11/2013 + SST: ERSST 1880-11/2013

I.E. not Hadcrut.
Yet giss also shows a pause in the warming.

 

[gslack]

Hadcrut is simply one of the datasets of compiled land and sea surface temperatures used for determining average global temperatures by the Hadley center in the UK. I am assuming you are referring to the email scandal a year or 2 back, but that has nothing to do with the datasets. Moreover, the published study cited in the opening post has nothing to do with those emails either, and is simply arguing that the Hadcrut dataset was flawed due to their sparse instrument readings in parts of Africa and the poles. They show how taking Hadcrut datasets and supplementing them with satellite temperature measurements provides a better measurement of average global temperatures, and when this done, the pause in warming shown by Hadcrut is eliminated.

No I was talking about hadcrut.. It was introduced in march of 2012, so actually it was almost 2 years ago, my previous estimate was off by about 9 months...

I didn't mention climategate emails, and wasn't implying anything in their regard.

Your article stated a "...potential source of bias in global temperature reconstructions" and "Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect..

Hadcrut 4, meaning number 4 in the hadcrut revisions. HadCRUT 4 = combined instrumental temperature records, including sea surface data from Hadley Center (Had), and the land surface air temperature readings from the Climate Research Unit (CRUT) in University of East Anglia.. They were 3 revisions and the first Hadcrut was published in 94', followed by hadcrut 2 in 03', hadcrut 2 in 06', and then hadcrut 4 in 12'..

 

[gslack]

No I was talking about hadcrut.. It was introduced in march of 2012, so actually it was almost 2 years ago, my previous estimate was off by about 9 months...

I didn't mention climategate emails, and wasn't implying anything in their regard.

Your article stated a "...potential source of bias in global temperature reconstructions" and "Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect..

Hadcrut 4, meaning number 4 in the hadcrut revisions. HadCRUT 4 = combined instrumental temperature records, including sea surface data from Hadley Center (Had), and the land surface air temperature readings from the Climate Research Unit (CRUT) in University of East Anglia.. They were 3 revisions and the first Hadcrut was published in 94', followed by hadcrut 2 in 03', hadcrut 2 in 06', and then hadcrut 4 in 12'..

Correction to my previous post.. In the list of hadcrut revisions I listed hadcrut 2 twice, when it should read 2 and then 3.. My bad..

 

[ALiberalModerate]

No I was talking about hadcrut.. It was introduced in march of 2012, so actually it was almost 2 years ago, my previous estimate was off by about 9 months...

I didn't mention climategate emails, and wasn't implying anything in their regard.

Your article stated a "...potential source of bias in global temperature reconstructions" and "Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect..

Hadcrut 4, meaning number 4 in the hadcrut revisions. HadCRUT 4 = combined instrumental temperature records, including sea surface data from Hadley Center (Had), and the land surface air temperature readings from the Climate Research Unit (CRUT) in University of East Anglia.. They were 3 revisions and the first Hadcrut was published in 94', followed by hadcrut 2 in 03', hadcrut 2 in 06', and then hadcrut 4 in 12'..

I misunderstood you earlier. Yes, as you point out, HadCRUT 4 came out last year. It did not find a cooling trend though, just a decline in the rate of warming. Indeed I think they revised 2010 to be the warmest year on record. As to your assertion that:

"Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect.."

That is pure conjecture on your part. I would speculate that those behind this study believed that environmental observations over the last decade: declining sea ice in the arctic, vast areas of melting permafrost, rapid high altitude glacial retreat in mountain ranges around the world, tree lines increasing in altitude and so on.... indicated that the HadCRUT data was possibly underestimating warming over the last 10 years or so, and thus they looked to satellite temperature measurements to get a fuller picture.

 

[gslack]

I misunderstood you earlier. Yes, as you point out, HadCRUT 4 came out last year. It did not find a cooling trend though, just a decline in the rate of warming. Indeed I think they revised 2010 to be the warmest year on record. As to your assertion that:

"Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect.."

That is pure conjecture on your part. I would speculate that those behind this study believed that environmental observations over the last decade: declining sea ice in the arctic, vast areas of melting permafrost, rapid high altitude glacial retreat in mountain ranges around the world, tree lines increasing in altitude and so on.... indicated that the HadCRUT data was possibly underestimating warming over the last 10 years or so, and thus they looked to satellite temperature measurements to get a fuller picture.

So you are stating that the articles STATED claim is conjecture on my part? Then this statement;

"Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

Is actually not stating what it appears to state and when they say "Cool bias" they don't actually MEAN cool bias... RIGHT....

Tell ya what, you make up your mind what your article is stating, and then get back with me..:lol:

 

[ALiberalModerate]

So you are stating that the articles STATED claim is conjecture on my part? Then this statement;

"Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

Is actually not stating what it appears to state and when they say "Cool bias" they don't actually MEAN cool bias... RIGHT....

Tell ya what, you make up your mind what your article is stating, and then get back with me..:lol:

You realize that by their statement in the abstract they don't mean a bias on the part of the folks behind Hadcrut, they mean what I stated earlier that gaps in the instrumental record for land and sea temperatures have resulted HadCRUT underestimating warming. Being that its only been in the last few years that we have been able to get accurate surface temperature measurements from satellites, it is to be expected that scientists would now be using satellite data to supplement surface data.

 

[gslack]

You realize that by their statement in the abstract they don't mean a bias on the part of the folks behind Hadcrut, they mean what I stated earlier that gaps in the instrumental record for land and sea temperatures have resulted HadCRUT underestimating warming. Being that its only been in the last few years that we have been able to get accurate surface temperature measurements from satellites, it is to be expected that scientists would now be using satellite data to supplement surface data.

Where did I imply it was due to the folks behind hadCRUT? You are obviously determined to argue something you want me to imply or say rather than what I write..

Previously you assumed something that I never even mentioned AT ALL, and then you stated reading what the article said was conjecture on my part, and now you try and make a false implication regarding what I actually said.. If you are going to just ignore what I write and argue what you want me to have written, this is going to be a very short conversation..

 

[Jack Hays]

From the abstract:



More here: Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends - Cowtan - Quarterly Journal of the Royal Meteorological Society - Wiley Online Library

It was pretty obvious the world's climate was continuing to warm significantly. One only had to look at the continual loss of Arctic Sea Ice, High Altitude Glacial Retreat and so on.



[/FONT][/COLOR]

Fictional data to explain the absence of warming in the real world.eace

[h=2]‘Twas the nightmare before Christmas[/h] Posted on December 18, 2013 by Guest Blogger
Snow in Jerusalem, Dec 13th, 2013. Source: Dosmagazine – click for story

By Joe Bastardi ‘Twas the week before Christmas, when all through the news, there were reports of record cold , so many were confused;
Told global warming is why we should care, And that the point of no return would soon be here; The children were bombarded with tales of dread, While visions of climate disasters were stuck in their heads;

And mamma in her Prius , and I on my bike, To save the planet, got rid of the cars that we like. When suddenly in the data there arose such a clatter, The earth was not warming, what could be the matter? Continue reading →

 

[ALiberalModerate]

Where did I imply it was due to the folks behind hadCRUT? You are obviously determined to argue something you want me to imply or say rather than what I write..

Previously you assumed something that I never even mentioned AT ALL, and then you stated reading what the article said was conjecture on my part, and now you try and make a false implication regarding what I actually said.. If you are going to just ignore what I write and argue what you want me to have written, this is going to be a very short conversation..

The abstract stated this: "Coverage bias causes a cool bias in recent temperatures relative to the late 1990s which increases from around 1998 to the present. Trends starting in 1997 or 1998 are particularly biased with respect to the global trend."

I stated that when you restated that as the following, it was pure conjecture on your part:

"Pretty clear their implication was that hadcrut4 gave a cooling trend which they disagree with. Assuming "they" are many of the same researchers who previously supported and confirmed past datasets and claims that were showing an opposite or differing effect.."

So, if I am not mistaken, you are claiming that the researchers behind the study in the opening post, only did the study because HadCRUT 4 shows a reduction in the rate of warming. That is simply speculation on your part. If you read the study, it indicates that they conducted it because satellite temperature measurements (which are fairly new) differ from HadCRUT and find a cooling bias in HadCRUTs data. They then go on to explain, with empirical evidence, why there is a cooling bias with HadCRUT data and what caused it. That is how science works. New ways of getting data comes about, and conclusions are reassessed. As I stated earlier, environmental observations were not indicating a reduction in the degree of warming, so its perfectly reasonable to look at satellite data for confirmation.

 

[ALiberalModerate]

Fictional data to explain the absence of warming in the real world.eace

[h=2]‘Twas the nightmare before Christmas[/h] Posted on December 18, 2013 by Guest Blogger
Snow in Jerusalem, Dec 13th, 2013. Source: Dosmagazine – click for story

By Joe Bastardi ‘Twas the week before Christmas, when all through the news, there were reports of record cold , so many were confused;
Told global warming is why we should care, And that the point of no return would soon be here; The children were bombarded with tales of dread, While visions of climate disasters were stuck in their heads;

And mamma in her Prius , and I on my bike, To save the planet, got rid of the cars that we like. When suddenly in the data there arose such a clatter, The earth was not warming, what could be the matter? Continue reading →

Yes that is weather. Strange things happen with weather. Let's look at climate. Despite the weird weather this month, November was the warmest November on record, and 2013 looks like it will be the 4th warmest year on record.

 

[Jack Hays]

Yes that is weather. Strange things happen with weather. Let's look at climate. Despite the weird weather this month, November was the warmest November on record, and 2013 looks like it will be the 4th warmest year on record.

There has been no warming for seventeen years, fictional pseudoscience notwithstanding.eace

 

[ALiberalModerate]

There has been no warming for seventeen years, fictional pseudoscience notwithstanding.eace

That statement is incorrect no matter how many times you repeat it.

2010 was the warmest year on record.
NASA: 2010 Meteorological Year Warmest Ever | Science/AAAS | News

9 out 10 of the warmest years on record have occurred in the last decade:
https://na.unep.net/geas/getUNEPPageWithArticleIDScript.php?article_id=53

The degree of growth in warming has certainly leveled off in the last few years as indicated here:

However, we have not cooled at all, but rather we got hotter and stayed hot for the time being rather than getting even hotter. In fact if you look at that graph you see sharp warming trends followed by sharp cooling trends over the last century, with another warmer trend following. What makes the last decade unique and even more troubling, is there has been no cooling trend with every year being historically warmer than normal.

 

[Jack Hays]

That statement is incorrect no matter how many times you repeat it.

2010 was the warmest year on record.
NASA: 2010 Meteorological Year Warmest Ever | Science/AAAS | News

9 out 10 of the warmest years on record have occurred in the last decade:
https://na.unep.net/geas/getUNEPPageWithArticleIDScript.php?article_id=53

The degree of growth in warming has certainly leveled off in the last few years as indicated here:

However, we have not cooled at all, but rather we got hotter and stayed hot for the time being rather than getting even hotter. In fact if you look at that graph you see sharp warming trends followed by sharp cooling trends over the last century, with another warmer trend following. What makes the last decade unique and even more troubling, is there has been no cooling trend with every year being historically warmer than normal.

Yawn.

Whither went the warmer weather?

Posted on December 16, 2013 by Anthony Watts
17 years, 3 months with no global warming
By Christopher Monckton of Brenchley
The Long Pause just got three months longer. Last month, the RSS monthly global mean lower-troposphere temperature anomalies showed no global warming for exactly 204 months – the first dataset to show the full 17 years without warming specified by Santer as demonstrating that the models are in fundamental error.
The sharp drop in global temperature in the past month has made itself felt, and not just in the deep snow across much of North America and the Middle East. The RSS data to November 2013, just available after a delay caused by trouble with the on-board ephemeris on one of the satellites, show no global warming at all for 17 years 3 months.

It is intriguing, and disturbing, that WattsUpWithThat is just about the only place where you will be allowed to see this or any graph showing the spectacularly zero trend line through 207 continuous months of data.
CO2 concentration continues to climb. Global temperature doesn’t. Absence of correlation necessarily implies absence of causation. Game over, logically speaking.
Continue reading →eace

 

[ALiberalModerate]

Yawn.

Whither went the warmer weather?

Posted on December 16, 2013 by Anthony Watts
17 years, 3 months with no global warming
By Christopher Monckton of Brenchley
The Long Pause just got three months longer. Last month, the RSS monthly global mean lower-troposphere temperature anomalies showed no global warming for exactly 204 months – the first dataset to show the full 17 years without warming specified by Santer as demonstrating that the models are in fundamental error.
The sharp drop in global temperature in the past month has made itself felt, and not just in the deep snow across much of North America and the Middle East. The RSS data to November 2013, just available after a delay caused by trouble with the on-board ephemeris on one of the satellites, show no global warming at all for 17 years 3 months.

It is intriguing, and disturbing, that WattsUpWithThat is just about the only place where you will be allowed to see this or any graph showing the spectacularly zero trend line through 207 continuous months of data.
CO2 concentration continues to climb. Global temperature doesn’t. Absence of correlation necessarily implies absence of causation. Game over, logically speaking.
Continue reading →eace

If he has some "new data" that contradicts everyone else then why doesn't he submit it to a respected Scientific Journal rather than blogging about it?? As it is, he just looks like the "unskewed polls" guy back in 2012 that was predicting a Romney win in a landslide. I find it intriguing and disturbing that you would dismiss mainstream science out of hand and put your trust in some blogger. If this guy's arguments are so rock solid, then why doesn't he convince his peers? I am sure you feel like its all some big conspiracy.

Moreover, the guy is not even using surface temperature observations. He is using upper atmosphere data. Its long been known that in a warming climate where CO2 was the primary climate forcing agent, we should see a warming surface and a cooling stratosphere as more heat is trapped in the oceans, surface, and lower troposphere and less heat is radiated back into space. The only reason why we should see an upward trend in that particular graph you posted would be an increase in solar forcing (or a massive greenhouse effect increase). The point being the guy is so ignorant of climate science, or being so willfully deceptive, that he posts data that actually works against what he is trying to argue.

He even went so far as to mislabel his own graph as surface readings when its not. http://www.remss.com/measurements/upper-air-temperature

 

[Jack Hays]

If he has some "new data" that contradicts everyone else then why doesn't he submit it to a respected Scientific Journal rather than blogging about it?? As it is, he just looks like the "unskewed polls" guy back in 2012 that was predicting a Romney win in a landslide. I find it intriguing and disturbing that you would dismiss mainstream science out of hand and put your trust in some blogger. If this guy's arguments are so rock solid, then why doesn't he convince his peers? I am sure you feel like its all some big conspiracy.

Moreover, the guy is not even using surface temperature observations. He is using upper atmosphere data. Its long been known that in a warming climate where CO2 was the primary climate forcing agent, we should see a warming surface and a cooling stratosphere as more heat is trapped in the oceans, surface, and lower troposphere and less heat is radiated back into space. The only reason why we should see an upward trend in that particular graph you posted would be an increase in solar forcing (or a massive greenhouse effect increase). The point being the guy is so ignorant of climate science, or being so willfully deceptive, that he posts data that actually works against what he is trying to argue.

He even went so far as to mislabel his own graph as surface readings when its not. Upper Air Temperature | Remote Sensing Systems

The data already gets published by these guys. It's not "his" graph; it's the data your respected scientific journals, NASA, NOAA, etc. use.eace

1. [h=3]Upper Air Temperature | Remote Sensing Systems[/h]www.remss.com/measurements/upper-air-temperature‎
   RSS air temperature products are assembled from measurements made by the MSU .... Monthly maps of MSU/AMSU brightness temperatures and brightness ...
   
   
   
2. [h=3]MSU / AMSU | Remote Sensing Systems[/h]www.remss.com/missions/amsu‎
   Satellites can measure the temperature of the atmosphere by evaluating ... RSS studies the measurements made by 3 series of satellite-borne ... Figure 1 below shows an example plot of which satellite contributes valid data for each month.
   
   
   

 

[ALiberalModerate]

The data already gets published by these guys. It's not "his" graph; it's the data your respected scientific journals, NASA, NOAA, etc. use.eace

1. Upper Air Temperature | Remote Sensing Systems
   
   www.remss.com/measurements/upper-air-temperature‎
   RSS air temperature products are assembled from measurements made by the MSU .... Monthly maps of MSU/AMSU brightness temperatures and brightness ...
2. MSU / AMSU | Remote Sensing Systems
   
   MSU / AMSU | Remote Sensing Systems
   Satellites can measure the temperature of the atmosphere by evaluating ... RSS studies the measurements made by 3 series of satellite-borne ... Figure 1 below shows an example plot of which satellite contributes valid data for each month.

Yes, but you don't seem to get that he is misattributing it. He has the graph marked as Global Mean Surface Temperature Changes, when its actually upper atmosphere readings. So he willfully represents the data he is blogging about.

Moreover, the opening post of this thread references a published study, not some blog post, that deals with the discrepancies between surface temperature records and satellite data. Read it, maybe you will learn something new.

 

[Jack Hays]

Yes, but you don't seem to get that he is misattributing it. He has the graph marked as Global Mean Surface Temperature Changes, when its actually upper atmosphere readings. So he willfully represents the data he is blogging about.

Moreover, the opening post of this thread references a published study, not some blog post, that deals with the discrepancies between surface temperature records and satellite data. Read it, maybe you will learn something new.

What makes you think it's "actually upper atmosphere readings?"eace

 

[Jack Hays]

Yes, but you don't seem to get that he is misattributing it. He has the graph marked as Global Mean Surface Temperature Changes, when its actually upper atmosphere readings. So he willfully represents the data he is blogging about.

Moreover, the opening post of this thread references a published study, not some blog post, that deals with the discrepancies between surface temperature records and satellite data. Read it, maybe you will learn something new.

Here is how they calculate lower troposphere, which is the subject of the graph. This is from the link I provided.

[h=4]TLT (Temperature Lower Troposphere)[/h]

---

TLT is constructed by calculating a weighted difference between MSU2 (or AMSU 5) measurements from near limb views and measurements from the same channels taken closer to nadir, as can be seen in Figure 1 for the case of MSU. This has the effect of extrapolating the MSU2 (or AMSU5) measurements lower in the troposphere, and removing most of the stratospheric influence. Because of the differences involves measurements made at different locations, and because of the large absolute values of the weights used, additional noise is added by this process, increasing the uncertainty in the final results. For more details see Mears et al., 2009b.eace

 

[DA60]

I am going to err on the side of caution and assume their IS significant global warning occurring until I see factual proof (not evidence - proof) to the contrary.