Jeff Id of the Air Vent has offered me this study he just completed for the consideration of WUWT readers. Given the wide audience we have here, I’m sure it will get a rigorous review and inspection. Let’s see how well it stands up. – Anthony
Closest Station Antarctic Reconstruction
In my last alternate reconstruction of Antarctic temperature I used the covariance of satellite information to weight surface stations. While the reconstruction is reasonable I found that it distributed the trends too far from the stations. This prompted me to think of a way to weight stations by area as best as I can. The algorithm I employed uses only surface station data laid on the 5509 grid cell locations of the Steig satellite reconstruction.
This new reconstruction was designed to provide as good a correlation vs distance as possible and the best possible area weighting of trend, it can’t make a good looking picture though but for the first time we can see the spatial limitations of the data. The idea was to manipulate the data as little as possible to make where the trend comes from as clear, simple and properly weighted as possible.
The algorithm I came up with works like this.
Calculate the distance from each of 42 surface stations to 5509 satellite points store them in a matrix 42 x 5509.
For each of 5509 points find the closest station and copy the data to that location. If there are missing values infill those from the next closest station looking farther and farther until all NA’s are infilled.
This is what the spatial distribution of trends looks like.
Figure 1
You can see how the trends are copied to the points of each polygon from each surface station. There’s quite a bit of noise in the graph but it seems that like temperatures are grouped reasonably well together.
The code looks for the above plot takes about 20 minutes to run.
#calc distance from surface stations to sat grid points
dist=array(0,dim=c(5509,42))
for(i in 1:42)
{
dist[,i]=circledist(lat1=Info$surface$lat[i],lon1=Info$surface$lon[i],lat2=sat_coord[,2],lon2=sat_coord[,1])
}
Circledist is Steve McIntyres’s great circle function with slight modifications.
circledist =function(lat1,lon1,lat2,lon2,R=6372.795)
{
pi180=pi/180;
y= abs(lon2 -lon1)
y[y>180]=360-y[y>180]
y[y<= -180]= 360+y[y<= -180]
delta= y *pi180
fromlat=lat1*pi180;
tolat=lat2*pi180;
tolong=lon2*pi180
theta= 2* asin( sqrt( sin( (tolat- fromlat)/2 )^2 + cos(tolat)*cos(fromlat)* (sin(delta/2))^2 ))
circledist=R*theta
circledist
}
Then I wrote a function to get the closest distance greater than a value ‘mindist’ I pass. The first call for the grid number ‘ ind’, mindist is set to zero and the closest station is returned. If the closest station has missing data, I infill what it does have and pass the distance from the closest station to mindist and get the second closest station returned. The process is repeated until all values are filled.
getnextclosestdistance = function(ind=0,mindist=0)
{
tdist=dist[ind,]
while(min(tdist)<=mindist)
{
mind=min(tdist)
if (mind<=mindist)
{
tdist=tdist[- (which(tdist == min(tdist), arr.ind = TRUE)[1])]
}
}
g= which(dist[ind,] == min(tdist), arr.ind = TRUE)[1]
g
}
This is the loop function that fills the array.
recon=array(NA,dim=c(600,5509))
recon=ts(recon,start=1957,deltat=1/12)
for (i in 1:5509)
{
lastdist=0
while(sum(is.na(recon[,i]))>0)
{
dd=getnextclosestdistance(i,mindist=lastdist)
lastdist=dist[i,dd]
mask = is.na(recon[,i])
recon[mask,i]=anomalies$surface[mask,dd]
print (paste(i,lastdist))
}
}
After that all that’s left is the plotting algorithms by RomanM SteveM and Jeff C which I’ve shown before.
The next graph is the trend calculated from all 5509 grid points.
Figure 2
The trend is again positive by 0.052 C/Decade, this time it is on the outer edge of the stated 95% confidence interval of Steig09 of 12 +/- 0.07C/Decade.
Like before I also looked at the trend from 1967 – 2007.
Figure 3
Figure 4
So from this reconstruction temperatures have dropped since 1967 at an average rate of 0.31 C/Decade. These results are similar to my previous reconstruction which looks like this.
The Antarctic, an engineers reconstruction.
Figure 5
Figure 6
And from 1967 – 2007
Figure 7
Figure 8
While I was initially happy with the engineers reconstruction, I found that station trends were not well localized by linear correlation weighting. (The correlation vs distance was not good) While peninsula station information stayed localized, the rest of the continent spread widely.
The trends shown match my last reconstruction reasonably well but in my opinion these are of superior quality.
Certainly the Antarctic temperatures have been flat or insignificantly cooling/warming in general for the last 40 years while 50 years ago there were lower temps recorded causing a very slight upslope in the 50 year trend. This is confirmed by the fact that sea ice has grown during the last 30 years among other observations.
The Steig 09 paper seems to be an artifact of the mathematics more than an actual trend. Amundsen Scott is the south pole data. The surface measurement is visually clean and has a downtrend for the full length of the data. This cooling is represented by the blue polygon in the center of the antarctic in this reconstruction.
TCO keeps asking me if I’ll post a trend higher than Steig. Every reconstruction I’ve done has reduced the trend from Steig 09. Every change no matter how small has resulted in a trend reduction from Steig 09, even the attempt to match Steig 09 has resulted in a slight trend reduction. I’ll say it now for the first time. In my opinion the paper is flawed and has an exaggerated warming trend due to bad mathematics. Temperature distributions on the continent are a result of artifacts in RegEM and not supported by the natural weather patterns as they were presented.
As an example which is pretty clear. Steig’s paper shows warming across the entire Antarctic. Here’s a plot of the ground data at the south pole.
Figure 9
A reconstruction cannot ignore a trend this strong. So TCO, it isn’t up to me. As Gavin likes to say, the data is the data. This data just cannot support Steig’s conclusions.
I always thought that air temperatures, besides differing by location and altitude were also affected by, among other factors, the character of the air mass upwind.
Just doing some sort of positional interpolation by estimated position would seem to be logically inadequate.
And I’ll freely admit that I am not familiar with R code, but I don’t think these temperature interpolations even include elevation corrections, let alone any dynamic air mass adjustments.
To John H. RE: My science credentials. For starters, please read: (1) “Tar Sands:
Key Geologic Risks and Opportunities,” a peer-reviewed paper published in
the Sept 2008 issue of The Leading Edge. TLE is the monthly technical journal
published by the Society of Exploration Geophysicists. The SEG is headquartered in Tulsa, OK and has 30,000 worldwide members, (2) “Conventional Petroleum Assessments: Facts and Fallacies,” published in the 1980 Canadadian Society
of Petroleum Geologists Memoir No. 6, “Facts and Principles of World Petroleum
Occurrence,” pp 283-300, and (3) Chairman and Editor of, ” Oil Fields of Alberta Supplement – 1966,” published by the Alberta Society of Petroleum Geologists, 136 pages of detailed field maps with valuable geologic and reservoir information. Check out the internet for more.
Pamela, the topic of discussion was originally the challenge to Steig’s alleged warming of present day Antarctica. Justin Sane asked about the last time Greenland and Antarctica were ice free.
You responded to his questions by saying:
Your comment is simply not true. We know “ice was [NOT] just the natural consequence of living at that address,” because we know Greenland and Antarctica “ arrived at or near the poles” and “the natural consequence of living at that address” were warm temperate, cool temperate, and cold unglaciated climates. During most of geological time, the polar regions remained free from permanent ice sheets and glaciations. Major continental glaciations occurred in Greenland, Antarctica, and any other continent only in those time periods during which one of the five major ice ages occurred. In other words, the polar areas supported glaciation of continental landmasses and polar sea ice ONLY during the occurrence of a global ice age climate. We currently live in the Holarctic-Antarctic Ice Age, which is why we currently see Arctic and Antarctic ice caps.
Ice caps existed in the regions of the Antarctic Circle and the South Pole only during at least five ice ages. The five ice ages are:
Huronian Ice Age 2500—2100 Ma, duration ~400 million years
Stuartian-Varangian Ice Age 950—600 Ma, duration ~50 million years
Andean-Saharan Ice Age 450—420 Ma, duration ~30 million years
Karoo Ice Age 360—260 Ma, duration ~100 million years
Holarctic-Antarctic Ice Age 30 Ma -– to present so far
The seas at the North Pole have rarely ever experienced polar ice caps . Even during the major ice ages, the seas in the north polar Arctic Circle remained unfrozen and free of ice packs.
Although the current Holarctic-Antarctic Ice Age began in the continent of Antarctica while it was already located within the Antarctic Circle about 30 million years ago, large areas of Antarctica remained free of glacial ice sheets and experienced tundra and cool temperate conditions until only a few million years ago.
Likewise, present day glacial ice sheets did not make their appearances in Greenland, Upper Canada, Alaska, and Iceland until 10–3 million years ago. Even then, Southern Greenland remained free of ice sheets and had cool temperate forests. The current Greenland ice sheet is estimated to be older than 110,000 years and perhaps up to 250,000 years old in origin from mountain glaciers.
In other words, the only time an ice cap existed at the North Polar region and/or the South Polar region was during the comparatively unusual occurrence of a major global ice age. At any other time, a continental landmass remained free of glacial ice sheets and the seas remained free of maritime ice sheets.
Hey Fred from Canuckistan: I nominate your post above as Best Example of Unintentional Irony for today.
David Ball, I suggest you examine the UNEDITED Vostok ice core data.
Sliiiightly of topic:
I recommen all to follow the ice situation at Bering:
http://nsidc.org/data/seaice_index/images/daily_images/N_daily_extent_hires.png
Right now, we have NH ice extend around normal, but the NICE thing is, that the missing ice is in the east Siberia, while there is extra ice around Bering!
And thats good news if you want ice at the north pole this summer, because the normal melting often starts from the Bering area. I have followed this for weeks and the Bering anomaly just gets bigger and bigger!
CodeTech (18:53:44) : Nature doesn’t make straight lines.
Hmmm. How about crystal growth? Plenty of straight lines and even planes.
D. Patterson,
All the ice ages you mentioned occurred where there was major landmasses (including one when all the continents were locked together over the south pole).
How many times in geologic history has there been major landmasses at one or both poles and there has not been ice there.
What happens to the climate of these landmasses during the six months of darkness they experienced.
I note that glaciers do not build up on the ocean. Secondly, if the ocean and deep ocean currents have full access to the polar regions, they will carry away the cold water and replace it with warmer water at the surface.
D. Patterson (09:13:31) :
Thanks for your timelines. Hundreds of millions, tens of millions, and hundreds of thousands of years is a very hard concept for most to understand, especially with cro-magnon man being around only for 35 thousand years and recorded history being only 5 or 6 thousand years (half the Holocene).
I wish politicians were able to understand these things.
Pamela Gray (19:37:36) :
Try http://www.globalwarmingart.com and stick to all graphs which use one and the same proxy, the O-18 ratio. More recent graphs mix/match/delete proxies (thermometers, pine needle stomata, tree ring width all species dependent, etc.) as needed to prove their points. The clearest graphs are the 0-450,000 years, 0-5 million years, 0-65 million years, and 0-540 million years.
The spotlighting of a The-Antarctica-May-Not-Be-Cooling-After-All contrived article in a formerly respected nature publication merely illuminates the weakness of the AGW position.
When a litigator is faced with “bad” facts he tries to argue about extraneous issues. If the AGW theory were sound, supporters would simply repeat the scientific evidence. Faced with satellites recording a cooling atmosphere, 3,000 diving buoys recording cooling oceans, positive correlations between temperatures and natural factors such as solar variations, and negligible to negative correlation between CO2 and temperature, AGW enthusiasts must go to the ends of the earth to pick an issue to argue about.
Don B (11:12:51) :
Right on, Don.
“”” jorgekafkazar (21:11:38) :
CodeTech (18:53:44) : “I hate straight lines…They always will remind me of Homer Simpson buying Pumpkin futures… they were going up and up (just before halloween), and ‘if this trend continues, we’ll be rich in 2 years!’ Nature doesn’t make straight lines.
If you ever took Freshman Chemistry, you’d know that is false. Or Geology 100. Or Botany 101. “””
“”” woodNfish (10:24:33) :
CodeTech (18:53:44) : Nature doesn’t make straight lines.
Hmmm. How about crystal growth? Plenty of straight lines and even planes. “””
What have you guys been smoking ?
Actually nature doesn’t make ANY of the things we use in mathematics. It’s all agreat fiction; and we made it up in our heads; ALL OF IT.
There are NO points, NO straight lines, NO planes, NO circles, NO spheres.
Don’t even bother to think of ANY mathematical “thing” that exists in nature.
Take the equation x^2 + y^2 + Z^2 = r^2 which in Euclidean Geometry defines a SPHERE, a purely fictional construct that is the locus of all points equidistant from a given point. Well points don’t exist either; but even so, nothing in that sphere equation can explain the existance of 8000 metre high mountains on earth; which lcearly is thereofre NOT a sphere.
Our mathematical constructs are not even unique.
In ordinary Euclidean plane geometry, a circle is a special case of an ellipse; a conic section.
But in the plane geometry called “Projective Geometry”, a circle is still a conic section but it is a special case of a hyperbola; and like all hyperbolas it is infinite in extent; and in fact every possible circle intersects every other possible circle at the same two points. There are points in Projective Geometry, just as in Euclidean Geometry; in fact one of the Axioms of projective geometry says that there are at least four points. The very first theorem one can prove with projective geometry is that there are at least seven points. But you can’t prove there are any more than seven points; within the bounds of porjective geometry.
You can however prove all of the classical geometry theorems of Euclid in projective geometry.
So no nature doens’t make straight lines. And you only need to know of Heisenberg’s principle of uncertainty to know that points don’t exist either; because if there was a point in the mathematical sence the uncertainty in momentum would spread the associated energy over an infinitely wide spectrum,so that it was undetectable at any frequency.
Mathematics is all made up by man, and nature doesn’t pay any special attention to man; or mathematics.
George
woodNfish: Codetech is right, nature abhors straight lines. What you see straight it is an ilussion of your almost instantaneous and fleeting vision.
There is only one curve: The spiral, having many projections, one of which is the sinusoid. If we were to see the solar system in a blink of an eye of, say, 30.000 thousand years, what should we observe?
George E. Smith (11:27:14) : You are probably right
By the way..I found it!, I know where greenhouse works: within a “Klein bottle”
Randall Arnold, if your claim is that Co2 precedes temperature rise in the ice cores, you will need to back that up. I am afraid you have not been clear in your challenge to my post. Did you read my post correctly ? What is your meaning of UNEDITED Vostok ice core data? Cut and run is not a great debating technique, although I see it a lot here.
@Matt Bennett and Jack Century
Do either of you actually have something to add to the discussion of the article presented above? Would you like to point out a flaw, or perhaps an oversight on behalf of Mr. Id?
In the wider debate of AGW your points are welcome, but in a discussion of a specific bit of research your comments serve only to derail and clutter a legitimate discussion. I don’t take you for fools or imbeciles so I can only assume you’re aware that your comments are out of place and disruptive. If you are indeed aware of that then your intent here is a deliberate disruption of the discussion. And if that much is true it means you’re here purely in an intellectually dishonest capacity.
I’ve assumed you not to be a fool or imbecile but that assumption leads me to believe you’re being intellectually dishonest. So would you have us believe you a fool or an academic miscreant?
You’ll have to forgive my blunt comments if they are misplaced but frankly I think you’ve shown an extreme lack of respect for the work Mr Id has done. I dare say you would find it equally disrespectful if the positions were reversed.
George E. Smith. I aways thought my math was half decent, but yours is light years better than mine. Good post. I always enjoy your comments. fm
Jeff,
I seem to recall a post over on Climate Audit where you apologised to Dr Steig due to an error in one of your reconstructions which had been discovered by Steve McIntyre. What impact does this error, and apology, have on a) your previous post on WUWT which demolished the Steig paper, and B) this post which furthers the demolition.
Many thanks
S
HarryL
“…would like to counter a few Alarmists accusations that there is no such thing as volcanism in the western antarctic ocean.”
I don’t have any studies to offer but point them to Google Earth which shows the proximity of the peninsula to the tip of S. America. The mountains go underwater and you can follow them with your finger (kinda sorta).
To C. Shannon: Thanks for focusing on issues of reconciling differences between geoscience and engineering disciplines, important in solving
serious problems related to global warming and climate change. However,
your assumption that I am not, along with others, a fool. an imbecile or dishonest it totally gratutitous. This important and very detailed subject under discussion is being monitored by responsible professionals for relevance, substance and style. My comments have been in response to a number of inapproprate remarks made about me and my credibility. In my opinion, your comments have succeeded in raising doubts about judgment and objectivity, as well as insulting the monitors.
REPLY: It appears you are only interested in your own issues, not the subject of this thread. Since you haven’t discussed anything about this thread, only about your ideas, you clearly have nothing to add on this thread that is relevant to the subject matter. Others agree. So off to the troll bin with you for this discussion.
Bill Illis (11:07:49) :
It is simpler to say how many times major landmasses have NOT been in the Antarctic Circle in about the past 650 to 1100 million years with or without an ice cap, which is virtually none. Earth’s continents formed after the Late Heavy Bombardment during the Archean Eon about 3800—2500 Ma, and it is reported that about 70 percent of today’s continental landmasses are formed from these very ancient cratons we describe as today’s continental shields. Because severe metamorphosis of these early continental rocks has changed their original geomagnetic and other properties to such a great extent, paleogeographers find it difficult to determine with any confidence exactly where the continents were located before about 650 Ma, but they have made some informed speculations back to around 1100 Ma with respect to a supercontinent dubbed as Rodinia. From about 1100—650 Ma to the present day, there has almost always been a continental landmass at the South Pole. On the few occassions when there has not been a continental landmass at the South Pole, there has been one nearby and usually well within the Antarctic Circle. Except when there has been a major ice age underway, these continental landmasses at or near the South Pole remained free of an ice cap.
Continental landmasses do not appear to have drifted into the region of the Arctic Circle and the North Pole before an approach was made in the Pennsylvanian of the Late Carboniferous about 300Ma and began to arrive at the North Pole about 220 Ma. Since then to the present day, there has always been a continental land mass within the Arctic Circle, at the North Pole, or near the North Pole with sub-continental islands at or nearby the pole as they are today. An icecap has formed within the Arctic Circle only during the ice ages. During the present ice age, the ice sheet extended far south of the Arctic Circle to the mid-latitudes, which is the only time this has occurred in the past 600 million years.
It varied depending upon the seasonality of the global climate. During periods in which the oceans were higher, the oceanic water’s heat capacity and circulation strongly moderated seasonal water cycles and global temperature gradients. Temperatures in the polar circles were often warm enough for temperate and/or tropical flora and fauna. During periods of lower oceanic levels and limited oceanic circulation, seasonal water cycles and temperature gradients became relatively extreme. Seasonal snow and ice sometimes appeared in the polar circles without becoming permanent glaciations.
“What impact does this error, and apology, have on a) your previous post on WUWT which demolished the Steig paper, and B) this post which furthers the demolition.(?)”
From my perspective, the apology adds further weight to Jeff’s posts and comments since he is obviously ready to admit errors when they occur. If only the high counsels of AGW could do likewise, but if they did that, belief would be much tougher to instill in the masses.
I take it back, I believe that if they were more willing to admit mistakes they would increase their persuasiveness. That readiness to admit any shortcomings does not seem to be part of that mindset, however…
AJStrata (08:30:52) :
The problem was the satellite data (which I don’t think they’ve released) doesn’t cover the full period of time nor exactly the same area as all available data. So Steig et al thought they could compare the satellite data to the concurrent surface station data to get some magic formula. Then they’d take whatever station data was available prior to the satellite data, spread it out to cover the same area, then apply the magic sauce to that so they could pretend IT was as good as satellite data.
Yeah, me too.
Opinions regarding the superiority in sampling frequency and quality of satellite v surface station data have been aired, and I have no disagreement with the greater potential of satellite data. However, surface stations, in my opinion remain essential.
With the greatest respect to the huge achievements in satellite remote sensing and measurement in recent decades, and also the greatest expectation of satellite and deep space mission data providing a revolution in Earth and planetary scientific understanding in the future, some means of standardised calibration zeroing and Q/C to selected surface standard base stations should be mandatory, to provide a future accuracy-assurance reference base. Without such, re-analysis and re-assessment of such data, when it becomes archived with the passage of time, may in future be regarded as unacceptably uncertain. The millimetric accuracy and correlation of satellite sea level data to surface tidal guage data , for example, has been disputed on a recent thread and is another area of possible future uncertainty which should be minimised. Such a process may already be instigated, in which case, apologies for my ignorance. But If so I would like to see the standard calibration stated and referenced as a matter of routine.
Shane,
That was a guest post by Jeff C who apologized to Dr. Steig. I didn’t feel the post attacked Dr. Steig at all so I just apologized to the readers for my own faulty verification.
This post is another story entirely, we’ve created several different reconstructions now.
– Automatic Weather stations
– Re-Gridded Automatic Weather stations (several recons)
– 3 pc sat recon from Steig’s 3 pc data
– 3 pc sat recon from steig’s raw sat data
– 10 pc sat recon from steig’s raw sat data
– 3 pc sat recon no peninsula from steig 3 pc data (I forgot about this one)
– Correlation weighted recon from raw sat data
– Area weighted recon from surface data only (this post)
I’ve got a couple more to do without the peninsula. Then I’ll do a post compiling everything. Ryan 0 on CA is working on a unique calibrated version of the sat data as well.
Not many conclusions yet except I seem to be incredibly lucky in that all of my and Jeff’s efforts seem to result in a reduced trends.