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Post by stranger on Jan 23, 2010 2:20:09 GMT
In general, 0.2 C is within the margin of error of satellite based instruments. And so many of the ground based monitoring stations have been compromised in one way or another that most of the ground based data must be discarded. The reliable data from uncompromised ground stations seems to show a decline of a half degree C a century.
Yes, that would be highly significant over a millennium or two.
Stranger
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Post by hunter on Jan 23, 2010 4:19:56 GMT
[/quote]"A global wide increase of nearly 0.2 deg is highly significant. [/quote]
In what possible sense of the word 'significant'?
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Post by trbixler on Jan 23, 2010 5:51:02 GMT
eric That is what is called a positive anomaly. If you take enough Darwins and correct them ( always upward ) you get the AGW results that some people suggest are perfectly normal. I like cartoons too but not from government agencies paid with our tax dollars.  |
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Post by hairball on Jan 23, 2010 7:38:51 GMT
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Post by glc on Jan 23, 2010 12:44:36 GMT
In general, 0.2 C is within the margin of error of satellite based instruments. And so many of the ground based monitoring stations have been compromised in one way or another that most of the ground based data must be discarded. The reliable data from uncompromised ground stations seems to show a decline of a half degree C a century. Yes, that would be highly significant over a millennium or two. Stranger You are confusing a single observation with thousands of observations. I'm going to try and answer this clearly using a non-scientific illustration. Let's say you wanted estimate the height of males in the US. If you simply looked at one random male you'd probably be way out. You might pick someone who was 6ft 4in or 5ft 2in. If you select 10 men your estimate will improve, but it's when you get to sampling around 1000 that the likely error becomes 'acceptably small'. If we have a sensor or thermometer with an accuracy of + or - 0.2 deg then it is just possible that 2 measurements of the same temperature could yield a difference of 0.4 deg. However the average would be spot on. Measurement errors tend to be random and follow a distribution which means that there are roughly the same number of high readings as low readings. In other words they more or less cancel each other out. Whatever error does remain it will be much less than 0.4. I did a demonstration some time ago which showed you could probably detect a 0.5 deg increase in temperature using a thermometer which only measured to the nearest degree. Now, all this has nothing to with any uncertainties due to the variability in the data. There is a whole field of statistics relating to error analysis and suchlike but this is well beyond the scope of this blog. |
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Post by trbixler on Jan 23, 2010 14:20:45 GMT
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Post by trbixler on Jan 23, 2010 17:59:17 GMT
Thousands of points and here is one series. Maybe GISS missed the adjustment oh wait it is CRU. "The temperature decline from 1975 to 2010 is approximately the same as for San Diego, California, yet the inland city of Fresno, California shows no such decline. " Now if we select the sites and drop maybe 4000 stations then adjust...... "Eureka (CA) Headed for Ice Age in 67 Years"  sowellslawblog.blogspot.com/2010/01/eureka-ca-headed-for-ice-age-in-67.html |
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Post by trbixler on Jan 23, 2010 18:12:54 GMT
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Post by trbixler on Jan 23, 2010 20:43:29 GMT
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Post by hunter on Jan 24, 2010 0:43:57 GMT
That last temp station looks like it will have nice warm evening temps, all summer long.
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Post by socold on Jan 24, 2010 13:47:55 GMT
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Post by elirabett on Jan 24, 2010 14:53:07 GMT
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Post by sigurdur on Jan 24, 2010 15:02:06 GMT
Taking out paintbrush.....  Depending on how you want to use the stats, the US is flat, colder, or warmer. Being all three can be proven, I will go with observation and say it has been flat. There are regional variations, which would be expected. The warmest years of the 20th century are still during the 30's. In my region, the warmest years in a row were during the early 40's. Once again, regional. I computed this from unhomoginized temps. When I look at worldwide temps, I see no sense of alarm. We are still well within the temps of the Holocene Optimum, Roman Warm Period, and the MWP. We all know that co2 should have an effect on the earths temp. The question always goes back to sensativity of said co2, and what is happening with the major climate driver, h20. With the recent revelations of climategate, IPPC, etc it is also well known that major players, (note, players) will use whatever means available to drive the AGW agenda to their profit and way of thinking. Climate scientists with integrity will freely admit that what is known, and the responses to what is known, only show what is not known. In doing my regional thing and talking to the state climatologist, (PHD in climate science)......we have a very long way to go before we can actually make any kind of credible forcast long term. What happens on a daily scale with weather DOES affect the long term climate as those daily scales make long term climate. |
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Post by trbixler on Jan 24, 2010 16:00:37 GMT
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Post by socold on Jan 24, 2010 16:35:37 GMT
Seems like some blink charts need to be revisited for those that suggest that it makes no difference. Seems like some documentation and manuals need to be revisited for those suggesting the blink graphs depict something newsworthy. The blink graphs compare individual station records in June 2009 and January 2010. They don't depict anything strange going on. The graphs are of "raw GHCN + USHCN corrections". The reason for the "blink" is is because the "USHCN corrections" were changed. GISTEMP went from using GHCN+USHCN to GHCN+USHCN v2 as it's input. As the GISTEMP site documents: November 13, 2009: NOAA is no longer updating the original version of the USHCN data; it ended in May 2007. The new version 2 currently extends to July 2009. Starting today, these newer data will be used in our analysis. Documentation and programs will be updated correspondingly.
And the USHCN v2 site makes it clear how the algorithm was changed in a way that would alter the past data: In previous releases of the U.S. HCN monthly dataset, homogeneity adjustments were performed using the procedure described in Karl and Williams (1987). This procedure was used to evaluate non-climatic discontinuities (artificial changepoints) in a station's temperature or precipitation series caused by known changes to a station such as equipment relocations and changes. Since knowledge of changes in the status of observations comes from the station history metadata archive maintained at NCDC, the original U.S. HCN homogenization algorithm was known as the Station History Adjustment Program (SHAP).
Unfortunately, station histories are often incomplete so artificial discontinuities in a data series may occur on dates with no associated record in the metadata archive. Undocumented station changes obviously limit the effectiveness of SHAP. To remedy the problem of incomplete station histories, the version 2 homogenization algorithm addresses both documented and undocumented discontinuities.www.ncdc.noaa.gov/oa/climate/research/ushcn/#processingStrangely the "chiefio" guy seems to at least grasp all of the above, but still makes immaturely stupid remarks like: "Call me old fashioned, but I really liked it better when my history did not keep changing and past temperatures did not require frequent re-writing" |
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