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dharma
12-28-2008, 09:53 PM
from "amstocks82":

One of the critical elements of demonstrating global warming is providing the temperature measurements that prove it is happening. Therefore, accurate temperature measurements are key. This is why Dr. Hansen, one of the leading global warming advocates—who works closely with VP Gore and other politicians—is leading the effort to provide accurate temperature measurements from weather stations around the world. Dr. Hansen's global warming group is in charge of aggregating and analyzing data from temperature stations and providing this data on many different government web sites.

Many might think this is a simple task best done by a simple automated computer program which downloads the data and averages them in with other data from other weather stations. But this is not correct. The data can be misleading. Therefore, complex algorithms for analyzing the data have been created and are constantly updated due to changing conditions. There is sometimes confusion from people who download the temperature data and then download it again and find that the data were updated, usually showing warmer temperatures. But given the ongoing global warming, most errors will be on the conservative side and therefore, updates will tend to show more warming.

One problem that was recently uncovered by an internet blogger was that NASA had a very small and close to insignificant software problem which caused recent temperatures to be warmer than they should be. After the blogger indicated that NASA had the problem, NASA of course updated the record. But after making the change, 1998 was no longer the warmest year on record. Other recent years were also not as warm in comparison as they should be. After fixing the tiny software problem,1934 was the North American warmest year on record. The top 10 warmest years in the United States were 1934, 1998, 1921, 2006, 1931, 1999, 1953, 1990, 1938 and 1939.

But NASA wished to be very thorough with their analysis and have recently been applying Dr. Hansen's algorithms to the data from the 1920s and 1930s. This has shown that past temperature records were incorrect and 1934 was not the warmest on record but now ties 1998 as the warmest. There appear to be other errors as well which when corrected might cause 1934 to be much cooler than currently thought. If this happens, 1998 will once more become the warmest year on record.

One of the mysteries of climate science is why the satellite derived temperature data is incorrect. The satellite data would be expected to be less biased as they are measuring large areas at the same time and won't be impacted by errors. However, the satellite data rarely match those data provided by Dr. Hansen's group.

One recent example: in November 2008, data from Dr. Hansen's group shows that the temperature anomaly is 0.8001 for the Northern hemisphere—meaning the average temperature was 0.8001 degrees Celsius warmer than the average. This may be adjusted up over time as errors are found. But, the data from the satellites show that the the temperature anomaly is only 0.338. So far, with data for 11 months in 2008, the cumulative difference between the NASA data provided by Dr. Hansen's group and the satellite data is the highest ever for one year. This tends to indicate that the satellite data are becoming less reliable over time! One theory about this is that the instruments in the Satellite have gradually been losing sensitivity. In some years, they lose more than in others but they are tending to get more unreliable; the satellite data do not show all the warming that is occurring.

Since the satellite data comes through NASA, one way to fix the problem would be allow Dr. Hansen to fix the satellite data as well. Right now Dr. Hansen's group is unfortunately not in charge of the Satellite temperature measuring program. But under Obama, this could very well change. There are a few older less scientifically savvy scientists at NASA that don't believe in human induced global warming. Some of them unfortunately are managers and continue to impede the science of global warming! But with some of the changes from the Obama administration, some of these people can be allowed to retire. This will allow Dr. Hansen's global warming climate group to find out what is happening with the satellite temperature data and implement appropriate fixes such that they match the corrected data from the ground weather stations.

We will have to see, but it could be next year Dr. Hansen's group will be allowed to fix the clear bias in temperature data provided by the temperature measuring satellites, allowing global warming climate science to advance.

In this manner, progress can be guaranteed.

US Blues
12-28-2008, 10:35 PM
I sat thru just over an hour of Al Gore's movie about the "global warming"and CO2...

he's got all these photos and charts and graphs... sounds like Alice's Restaurant then he puts one up talking about total land masses, Northen vs Southern... and vegetation... and CO2... and I think, maybe he'll talk about the imbalance of vegetation... because plants take in CO2 , and put out O2 during the day, but at nite, they take in O2, and put out CO2... longer nites mean more CO2

No where does he chart the deforestation between the Tropics (where sunlight is 12hrs or more), nor the reforestation above 33 degrees.
Nor does he bother to chart sun fluxuations, along with variations in Earths orbit around the Sun.

Ross
12-28-2008, 10:50 PM
I find that a very disturbing piece of text , far more frightening in fact
than any looming depression .
When basic scientific measurements can be re-written to support
scripture I feel my very sanity is threatened.

dharma
12-29-2008, 12:18 AM
Ross, I come from a discipline (medicine) that is almost totally reliant upon, and is simultaneously highly skeptical of, scientific measurement. There are very, very few yes or no answers in medicine. Most data are suspect. One cannot look at a result and draw conclusions based on that result without taking into account things like the sensitivity and specificity of the test, distribution of normals and standard deviations used as cutoffs, clustering (mean, median, mode, bimodal?), accuracy/precision (two very different things), repeatability, etc., etc. up to and very much including the bugaboos of machine, operator, and interpretation error.

It is accuracy versus precision that I really wonder about when I read of the difficulties with climate measurement. Think of these things as when shooting at a target: if I have five shots clustered about the center, but they’re all an inch or so apart, my gun is accurate, but not precise. If I have five shots in a tight group less than a quarter inch apart, but sitting out on the edge of the paper, my gun is precise, but not accurate.

Obviously both of these qualities are important, but it is my experience that government agencies prize precision over accuracy, every time. The EIA can tell you, within a few tens of thousands of barrels (precision of hundredths of a percent) how much oil the world produced and used last week. Unfortunately, the data they (and everyone else) have to use are so poor that their accuracy is probably within three to four percent, at best. Alas, that is about what it takes to make the difference between $40 and $140 oil—so the EIA numbers are not very useful, except in broad strokes and over time.

So, when I read that about 70% of the land temperature measuring stations are giving invalid readings due to the heat island effect, what am I to think about the accuracy of the data retrieved from them? When I read that satellite measurements are corrupted by sensor drift (which I very much believe—all electronics drift), how much validity am I to accord them? I’ll bet the numbers are wonderfully precise; are they accurate? What is your guess?

Not to worry, say the GW folks: we have adjusted for error. HOW? How can the adjustments be anything but educated guesses, and how much of the “educated” part is politically motivated?

amstocks82 certainly has an opinion on that, eh?

Ross
12-29-2008, 06:45 AM
Dharma Thank-you for that . Since my earlier post I have done a little
reading on satellite remote temperature sensing and calibration . My illusions
of it being a stable easy method have been shattered .

Frankly I was a lot happier and less confused when ignorant . :D

Sysiphus
12-29-2008, 01:43 PM
It seems odd to me that we are not using ground data. I'd always thought that satellite data were a backup used to gauge the accuracy of ground-based data. But, it seems like they are looking at it the other way around.

Kassy
12-29-2008, 04:51 PM
I find that a very disturbing piece of text , far more frightening in fact
than any looming depression .
When basic scientific measurements can be re-written to support
scripture I feel my very sanity is threatened.

Boy yes. This really is very disturbing.

And 'amstocks82' is a well respected expert with good credentials who knows what he's talking about. The bug was in US land temperatures which isn't quite the same as global temperatures. The problem didn't involve 1998 directly but if you alter the input of subsequent years you really have to recalculate the mean. Scientific rigor and all that. Has nothing to do with any 'scripture' , it's just method.

http://www.realclimate.org/index.php/archives/2007/08/1934-and-all-that/langswitch_lang/in

Isn't it evil how those scientists are even melting the arctic ice to make it all conform to 'scripture'. :eek:

shalym
12-29-2008, 10:17 PM
Boy yes. This really is very disturbing.

Isn't it evil how those scientists are even melting the arctic ice to make it all conform to 'scripture'. :eek:

Yes...too bad the satellites don't agree with you...

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh

Fiddlerdave
12-30-2008, 03:32 AM
Yes...too bad the satellites don't agree with you...

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.shYes, the satellites are wrong. All the countries sending ships up there are just living in a fantasy world. The crews go to Somalia fleshpots and just claim they are sailing newly melted Arctic waterways, sending back CG graphics to fool their bosses.

Ross
12-30-2008, 06:48 AM
What can I say , guys are ssssoooo on top of it .
Have you looked out the window lately ?

http://samuelatgilgal.files.wordpress.com/2008/06/global-warming-hoax.jpg

dharma
01-04-2009, 11:22 PM
And 'amstocks82' is a well respected expert with good credentials who knows what he's talking about.
Well, yes, in my world he is. But for yours, perhaps this gentleman will do?

http://www.drroyspencer.com/research-articles/satellite-and-climate-model-evidence/