AcuuWeather meteorologist Joe Bastardi has a question about two datasets and asks: If it is darn warm, how come there is so much sea ice?
Bastardi asks a simple question: how can we have above normal temperatures in the Arctic and the Antarctic and continue to add to the global sea ice trend? After all we’ve been told by media stories that both the Arctic and the Antarctic continue to melt at a frenetic pace. But it looks like this year we’ll see another Arctic recovery as we’ve seen in 2008 and 2009.
Bastardi also wonders about something we routinely ask about here at WUWT: data adjustments. GISS seems to be stuck with Arctic positive anomaly, yet the sea ice isn’t cooperating. Of course just having a positive temperature anomaly doesn’t guarantee melt, but members of the public who are less discerning, who look at red hot color presentations like GISS puts out, usually can’t tell the difference.
For reference here are the images Joe uses in his presentation. I’m going to help out a bit too with some simple comparisons.
First The GISS Dec-Feb 2010 Global Surface Anomaly as Joe presents it in his video:
Note that in the warmest places in the Arctic according to GISS, there are few if any land thermometers:
Above: map of GHCN2 land stations (thanks to commenter Carrick at Lucia’s)
Note the cross section of the GISS data, most of the warmth is at the Arctic where there are no thermometers. The Antarctic comes in a close second, though it has a few thermometers at bases on the perimeter of the continent plus a couple at and near the center. Note the flat plateaus are each pole.
The effects of interpolation become clearer when you do a 250 km map instead of 1200 km:
All of the sudden, the hot Arctic disappears. It disappears because there are no thermometers there as demonstrated by the cross section image which stops at about 80N.
Interestingly, the global surface anomaly also drops, from 0.80°C at 1200km of interpolation to 0.77°C with an interpolation of 250km.
One of the things that I and many other people criticize GISS for is the use of the 1951-1980 base period which they adopted as their “standard” base period. That period encompasses a lot of cool years, so anomalies plotted against that base period will tend to look warmer.
This famous GISS graph of surface temperatures from weather stations, shown worldwide in media outlets, is based on the 1951-1980 period:
Uncertainty bars (95% confidence limits) are shown for both the annual and five-year means, account only for incomplete spatial sampling of data.”]
GISS doesn’t provide a utility to replot the graph above with a different base period on their webpage here http://data.giss.nasa.gov/gistemp/graphs/ but I can demonstrate what would happen to the GISS global maps using a different base period by using their plot selector here http://data.giss.nasa.gov/gistemp/maps/
Watch what happens when we use the same base period as the UAH satellite data, which is 1979-2009. The 1200km interpolated global temperature anomaly for Dec-Jan-Feb 2010 drops more than half to 0.38°C from 0.80°C. That number is not so alarming now is it? As for the graphic, the flaming red is still there in the same places because the anomaly map colors always stay the same, no matter what the absolute temperature scale is. In the first map with the 1951-1980 base period, the max positive anomaly was 6.4°C for 1200km and 8.8°C for 250km, while in the one below with the 1979-2009 base period the max positive anomaly of 7.1C If colors were assigned to absolute temperatures, this map would look cooler than it’s counterpart with the 1951-1980 base period.
And here’s the 250km presentation, note that the global surface temp drops to 0.34°C
So it is clear, with the GISS anomaly presentation, you can look at it many different ways, and get many different answers. Who decides then which maps and graphs with what base periods and interpolations get sent out in press releases? Jim? Gavin?, Reto? Consensus over coffee at Monks?
The answer as to what base period GISS chooses in temperature anomaly maps to present to the public is easily answered by looking at their main page here: http://data.giss.nasa.gov/gistemp/
Here’s a thumbnail of the page, and the full size version of the second graph from the top, note the caption on the top of the graph:
Clearly, they prefer the base period of 1951-1980 as the default base period for the public presentation [as well as 1200 km smoothing] and by choosing that, the GISS results look a lot more alarming than they might be if a different base period was used, such as the 1979-2009 period used by UAH and RSS.
Anomalies can show anything you want based of choosing the base period. For example, a simple thought experiment. I could choose a base period from 11,000 years ago, during the last ice age, and plot maps and graphs of today’s temperatures against that base period. Would we see red? You betcha.
Here’s a graph that shows reconstructed northern hemisphere temps at the end of the last ice age 11k years ago, they were about 4.5°C cooler than today. Granted it’s not a global temp, but close enough for government work.
So if I used a 30 year slice of temperature 11,000 years before the present as a baseline period, our GISTEMP map would look something like this:
Obviously the map above is not an accurate representation, just a visual guesstimate. The more excitable who frequent here will likely cry foul at my abuse of the image. But it does illustrate how choices of colors and baseline periods can have a distinct effect on the final visual. Using a cold baseline period in the past (in this case 4.5°C globally cooler than the present) makes the present look broiling hot.
Anomalies are all about the starting choices made by people. Nature doesn’t give a hoot about anomalies. Generally, people don’t either. Imagine if your local TV weather forecaster gave tomorrow’s forecast in anomalies rather than absolute temperatures. He might say something like:
It’s going to be a hot one folks! Tomorrow we’ll have a high temperature that is 0.8C warmer than the 1951-1980 historical baseline for this city. Dress accordingly.
Useful isn’t it? Even more useful if he’s the weatherman in Svalbaard and people anticipating a heat wave go out in shorts and tank tops in mid February.
While anomalies are fine for illustrating many things, including temperature, bear in mind it’s all about the starting conditions chosen by the individuals doing the analysis. It’s all about choosing a baseline “normal”, which is subjective.
So when Joe Bastardi looks at the GISS map of the world, sees red, and wonders why we have a growing ice presence, the answer is in the choice of baseline and the choice of colors used to calculate and represent the anomaly.
Interesting that between them, NOAA & GISS have pretty much got rid of the ’40s bump that Wigley & Jones were finding so problematical.
DaveE.
I think anomaly maps should be colour coordinated based on the value of the anomaly to the range annual temperatures for the location. That would put the variation into perspective compared to natural variability.
Here’s something you wouldn’t want to try at home:
Take an IR picture of your oven after preheating to 350.
Using the picture, tell me which part of the oven is now safe to touch without suitable protective gloves.
Do the same thing with a walk-in freezer.
Anomaly.
Interesting that the Northen Hemisphere has the most land mass and less ocean surface compared to the Southern Hemisphere. The temperature swings are also dramatically different from the Northen and Southern Hemispheres.
Re: Espen (04:02:09) :
The image you linked to shows no real trend – it just shows the extreme event of 2007, and that multiyear ice increased again in 2009. I postulate that it will increase further this year – let’s return to this thread in September and see who’s right 🙂
Yes, I was planning on that.
Multiyear ice has continued to decrease over 2009:
http://nsidc.org/sotc/images/npseaice_ssm_200902.png
I expect Feb 2010 will show some recovery though.
I know, I know, it’s picking nits, but this is a typo I just can’t stomach: “All of the sudden”. Obviously, it’s suppposed to be “All of a sudden”.
By the by, the reason it has started to bother me so much is that I find myself wanting to copy it! It’s sneaky that way!
Think they have introduced a brand new beverage HOT-AID instead of KOOL-AID, that´s all.
Are there not actual temperatures anymore?
SST from Unisys look closer to reality:
http://weather.unisys.com/surface/sst_anom.html
rbateman (05:28:42) :
I have been saying for quite a while now that you can safely put your unprotected hand into a pre-heated oven as long as you don’t touch anything solid.
People who cook do it regularly.
DaveE.
Oops.
Or liquid.
Only the air is safe.
DaveE.
In my company the leadership has a term for what tou just demonstrated. We call it “rebaselining” – if the story you’re trying to tell (usually a trend of some sort) isn’t showing right, redefine the starting point. Works wonders!
In a similar vein, my friend from the Army says if the metrics don’t look right redefine them – apparently a reference to Gen. Petreius’ (sp?) redefinition of the term “incident” for Iraq a few years back – which strangely enough coincided with a large drop-off of “incidents”
Doing crap like this is old hat in heavily beaurocratic and/or political organizations, usually by middle management types that are trying to justify their existence… so with that in mind, is anyone surprised that our friends from GISS would continue to change their presentations to ensure they’re dramatic?
While Bastardi is a scientist GISS post-normal new age/”let it be” scientists are real “bastardi” (plural of bastard in italian language) ☺
“revelations of malpractice by climate scientists.”
Excuse for putting this here? It’s too hilarious.
Look what youse skeptics have wrought. Good work.
Who writes this stuff ?
“The museum had intended to call it the Climate Change Gallery, but has decided to change this to Climate Science Gallery to avoid being accused of presuming that emissions would change the temperature.”
>>>> “The decision by the 100-year-old London museum reveals how deeply scientific institutions have been shaken by the public’s reaction to revelations of malpractice by climate scientists.
…-
“Public scepticism prompts Science Museum to rename climate exhibition
The Science Museum is revising the contents of its new climate science gallery to reflect the wave of scepticism that has engulfed the issue in recent months.
The decision by the 100-year-old London museum reveals how deeply scientific institutions have been shaken by the public’s reaction to revelations of malpractice by climate scientists.
The museum is abandoning its previous practice of trying to persuade visitors of the dangers of global warming. It is instead adopting a neutral position, acknowledging that there are legitimate doubts about the impact of man-made emissions on the climate.
Even the title of the £4 million gallery has been changed to reflect the museum’s more circumspect approach. The museum had intended to call it the Climate Change Gallery, but has decided to change this to Climate Science Gallery to avoid being accused of presuming that emissions would change the temperature.
Last October the museum launched a temporary exhibition called “Prove It! All the evidence you need to believe in climate change”. The museum said at the time that the exhibition had been designed to demonstrate “through scientific evidence that climate change is real and requires an urgent solution”.”
http://www.timesonline.co.uk/tol/news/environment/article7073272.ece
London Science Museum goes climate science neutral
LONDON, March 24 (Reuters Life!) – A new climate gallery at London’s Science Museum, sponsored byRoyal Dutch Shell (RDSa.L), will step back from pushing evidence of man-made climate change to adopt a more neutral position.
…
The new gallery follows an exhibition called “Prove It! All the evidence you need to believe in climate change” … It featured a poll showing a large portion of its visitors disputed the scientific evidence behind man-made climate change.
http://www.reuters.com/article/idUSLDE62N0ZH20100324?type=marketsNews
OT but of interest – The Register have done some digging re Lord Oxburgh. Independant? O dear, O dear
Oops: Chief Climategate investigator failed to declare eco directorship
‘Dracula’s in charge of the blood bank’
By Andrew Orlowski
http://www.theregister.co.uk/2010/03/24/climategate_oxburgh_globe/
HumanityRules (22:46:58) :
This seems very weak.
You can complain about colour schemes and so forth but it’s trends that matter and I think you know that.
But he showed you trends since the end of the last ice age. Yep, just like clockwork it looks like part of the natural cycle to me. Look at that image and ask yourself “would I be happier if we were still in the depths of the Little Ice Age?” I think not!
There has been a lot of discussion on this thread about the importance of trends. Can I remind everyone that linear trends are representations of changes in temperatures over a particular period of time. They are historical. They have no predictive power whatsoever, which is clearly demonstrated by the effect of selection choice of starting point.
Using linear trends as predictors of future temperatures would appear to be particularly futile if the climate is dominated by cyclic effects, as I believe to be the case.
Ralph (04:14:21) :
And do remember one more that my WUWT hot button is that these maps are not Mercator projections They are merely lat/long plots. A Mercator projection can only reach the poles if map is infinitely tall, and that would interfere with reading posts like this one.
How can you use a conic projection to map the entire world without making a gawdful mess of things? See http://www.quadibloc.com/maps/mco0301.htm
You might do okay with the Lambert cylindrical equal-area projection, but that dinks with both x & y axes. See http://en.wikipedia.org/wiki/Lambert_cylindrical_equal-area_projection
My personal preference is a simple sinusoidal projection, see http://www.quadibloc.com/maps/mps0401.htm and it’s used in some sources. While the projection itself is rather ugly, it only messes with the x axis, it’s easy to generate, it’s easy to remap into other forms, and it’s easy for pixel counting programs to use since it’s an equal area projection.
If I had time, I’d write a web app to take a lat/long map and generate a sinusoidal map.
I really need to go write a web page – it would save me a lot of rant time.
Once more:
IT’S NOT A MERCATOR PROJECTION!!!!!
Whew.
For those interested, I’m presenting the Environment Canada data that I’ve download in a blog:
http://cdnsurfacetemps.blogspot.com/
Not done with some of it yet, and more to post.
Oh, and no anomalies.
Hi All
Can I just point out that Danish does not show the warmth for winter 2009-2010 that GISS data does. The Danish datacan be accessed at this site:
http://ocean.dmi.dk/arctic/meant80n.uk.php
May I suggest that only one of the two data sets, GISS or the the Danish DMI can be accurate.
Which one though.
About the diagram showing the siting of GHCN2 land stations (3rd one down) :
Does Turkey have some sort of cultural fascination with thermometers? Japan and the USA are pretty dense, but Turkey !?!
And on and on and on the debate goes, where it stops nobody knows…. Joe Bastardi is one of my heroes. He seems to be one of the few that is able to extract himself out of the sand, looking at each individual grain, and look at the beach.
So where does “weather” stop and “climate” begin? There seems to be no agreement whatsoever over what defines a climate period (30 years, 60 years, 1000 years, or millenia) other than the seasons of the year. In human existance we experience approximately 60-90 yearly cycles of climate change with which we can identify on a personal scale. But applied against the larger periods of change it has different meanings, or no meaning at all depending where or personal experience begins on the larger cycles. Vostok says “ice age imminent” while any particular Summer forecast can be “beastly hot”.
To argue 1000 year cycles against a 10 year trending is totally useless. The public has a right to be angry over the disagreement. There is no accepted standard to give context to the debate. One would think that establishing basic definitions and rules of debate would get us off this Tower of Babel.
Since perception, especially by the public, plays a larger role in climate science, I think a minor issue, but one that tilts in favor of the alarmists, is the selection of a map projection to display the data. If indeed, high latitude areas do have relatively higher temperatures than their past history, then a world map that grossly exaggerates the area (size) of high latitudes is biasing perception toward global warmism. Look at the maps used in this article, Greenland, which is 1/6 the size of South America, appears to be bigger. Antartical appears to be bigger than South America and Africa combined!
There is no magic solution to this presentation issue. Showing the surface of a sphere on two dimensional surface is difficult, but there are better projections and other accommodations that could be made. Regardless, being aware of the issue is important because we are more affected by visual images than we realize.
Here’s the thing about being blinded by whatever certainty you have in your mind– you will take the smallest bit of data and try to make it fit your preconception. What is even worse is when the data that you’re trying to analyze has been intentionally or unintentionally selected to give a certainty perception.
What is happening in the arctic and antarctic? Which data do you believe? Each of us has to decide, using all of our best judgements and intuition, and data from multiple sources, including first hand accounts from individuals we trust. Even more importantly, we have to try to not want to see something in the data that is not there, or trust only the sources that give us that data that we want or expect to see.
My belief is that the those who believe that AGWT is likely correct, and those who are skeptical are both so far apart in their philosophical stance, that each will reject the others data simply because to accept it would cause too much cognitive dissonance. To add to that, then not only does the data become suspect, but those who gather and analyze the opposing data become suspect as well. This is true for both sides, though both sides will deny they do it. They have to discredit the other side while maintaining that their side has the “true” perspective and are being the honest side of the issue.
So what is going on in the arctic, or the antarctic? Does a person like me, who doesn’t which to join the “true believers” on either side of the issue simply throw up their hands and say, “oh well, there is no way of knowing because both sides are dishonest and refuse to be objective.” I currently refuse to accept that position. Rather, I try to read and study multiple sources of information, trying to sift out the data that may be corrupted by those who have a particular postiion to advance.
Now, I maintain that most of us who post on sites like WUWT, are abnormalities in the sense that we even care about this topic, as most people, the common person on the street really doesn’t. The average person will believe what their favorite pundit or cable channel spoon feeds them to believe on this issue– because they don’t care enough to spend the time to research it for themselves.
Anthony made an interesting statement yesterday, that got me thinking. He said at one time in the 90’s that he was actually an active believer in the opposite perspective– he actually thought that AGWT was correct. He’s obviously an incredibly intelligent person who has spent many hours looking at this issue. That statement has more credibility with me in terms of making me look at my own perspective on this issue than most other things I’ve read.
Specifically in terms of the issue of what’s happening in the arctic or antarctic, I still maintain that no matter what “goalposts” you want to use, that the arctic at least has been warming over the past few decades, and even if you doubt the temperature data, you can’t doubt the first hand accounts of those who live there and have seen the changes directly. These first hand accounts of permafrost melting, etc. are important corroborating evidence for me. This issue as to whether this is a natural cycle versus a AGW issue is an entirely different matter. Because AGWT clearly models the heating of the polar regions, then certainly the warming in the arctic supports the theory, but does not porve it of course. And here is where I part ways with many AGW skeptics, as they will try to deny that there even is any substantial warming in the arctic, despite the first hand accounts of those native tribes that live there.
RR Kampen (01:29:02) :
Maybe the Arctic sea ice ‘recovered’ to some extent because it is winter.
Also there was this peculiar temperature anomaly distribution associated with a record low NAO index.
Likely all Arctic sea ice older than two or three years will be gone by September 2010. Because that, in reality, is the trend.
http://nsidc.org/images/arcticseaicenews/20091005_Figure5_thumb.png
Logic?????? As you can see from your chart the amount of 1st ice increased significantly in 2008. This became a large increase in 2nd year ice in 2009. Are you really claiming that we won’t see a huge increase in “older” ice this summer? If you are then I can easily ignore all of your future posts. Only someone completely devoid of logic would make such a statement.