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Old Apr 14, 2013, 04:55 PM   #126
.Andy
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Originally Posted by zin View Post
And James Hansen is the lowest of the low when it comes to climatology, therefore the data on NASA's website is utterly false, right? .
If Hansen is the lowest of the low with decades of quality peer-reviewed research and a highly decorated and successful scientific career things are very dire indeed for climate denialists.
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Old Apr 14, 2013, 07:28 PM   #127
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Originally Posted by zin View Post
And James Hansen is the lowest of the low when it comes to climatology, therefore the data on NASA's website is utterly false, right?

If you're using that logic then I don't see why I can't.
Because it's not good logic.

We know who James Hansen is. We know his credentials and that he puts his work up to peer review.

We don't know who works under the pseudonym "Steven Goddard". We don't know his credentials and it's highly unlikely that he's published in any peer reviewed journals.

Other than that, they're just alike.

Last edited by citizenzen; Apr 14, 2013 at 08:03 PM. Reason: misspelled 'his'
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Old Apr 15, 2013, 08:54 PM   #128
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I have received a response from NASA (kudos to them for replying the same day).

He noted that the URL I was using for the 1999 data is very old (8 years old) and that the giss.nasa.gov/data/ directory hasn't existed since then (it was moved to the new data.giss.nasa.gov then).

He referenced me to this data set http://data.giss.nasa.gov/gistemp/graphs_v3/Fig.D.txt which he believes is what I was looking for. This is not the same as the data set I posted earlier in thread (just by looking at the numbers, you can see).

In addition, he linked me to this http://data.giss.nasa.gov/gistemp/graphs_v3/ area of the GISS website.

The graph second from bottom is the one we're looking at because it concerns one of the data sets I accused of being changed. It says:
Quote:
Annual and five-year running mean surface air temperature in the contiguous 48 United States (1.6% of the Earth's surface) relative to the 1951-1980 mean. [This is an update of Figure 6 in Hansen et al. (1999).]
I've highlighted the part that is necessary for further discussion. Hansen et al can be viewed on the NASA website here: http://pubs.giss.nasa.gov/docs/1999/...ansen_etal.pdf

Fig. 6 (very bottom of the PDF): the graph shows a noticeably different trend than the 2012 one currently on the GISS website. I have a very high belief that Fig. 6 in that report is using the 1999 data that I desire access to. This proves that the data used in the 1999 report for this specific metric is different to the 2012 data set; the graph in the PDF shows a cooling anomaly since ~1925, whereas the graph currently using 2012 data on the GISS website shows a warming anomaly since ~1925. In addition, you can easily see that since 1980, the warming anomaly in the 2012 version is considerably steeper than the 1999 version (2012 graphs can be viewed earlier in the thread and on the GISS website).

Despite the fact they themselves claim they changed the data ("..an update of Fig. 6 in Hansen et al"), the graphical differences prove that the data is different, but to what numerical extent I cannot be sure since the 1999 data set is not concretely provided in the report (it references other reports, which presumably reference other reports until eventually arriving at the real source). Therefore, the graphs I created (not the original ones very early in the thread, as those are not my creations) are inconclusive as the 1999 data set I used cannot be proven to be genuine, nor can it be proven to be fraudulent.

NASA have failed to provide me with the dataset that was used in the 1999 report. Alternatively, maybe they haven't, perhaps the original 1999 source is in the report somewhere, but I'm not prepared to scour through multiple secondary sources until I eventually (or not) arrive at it. If you want to potentially prove your claim that the 1999 data in my own graphs is fraudulent, then go right ahead, but quite frankly I am tiring of this thread for now.

Strangely, the direct PDF link is no longer working with the message "Access Denied". (See http://puu.sh/2AX8c at the time of this post). In order to download the PDF I would advise you right click and save as on this previous page http://pubs.giss.nasa.gov/abs/ha03200f.html

Last edited by zin; Apr 15, 2013 at 09:01 PM.
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Old Apr 15, 2013, 08:59 PM   #129
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Originally Posted by zin View Post
Despite the fact they themselves claim they changed the data ("..an update of Fig. 6 in Hansen et al), the graphical differences prove that the data is different, but to what numerical extent I cannot be sure since the 1999 data set is not concretely provided in the report (it references other reports, which presumably reference other reports until eventually arriving at the real source)
Thank you for sharing this.

The question then becomes one of why did the data change?

My suspicion is that an error was found, or a measure refined, that necessitated the update.

I doubt it was for any conspiratorial reason.
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Old Apr 15, 2013, 10:01 PM   #130
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For those interested, the changes from the 1999 Figure 6 to the latest version largely has to do with the modifications to methodology.

This 2001 paper describes many adjustments to the 1999 data series.

Dr. Hansen talks further about it here.

Subsequent updates are also listed here and here.
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Old Apr 15, 2013, 10:12 PM   #131
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For those interested, the changes from the 1999 Figure 6 to the latest version largely has to do with the modifications to methodology.
Had a feeling there was something like that behind it.
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Old Apr 20, 2013, 11:44 AM   #132
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I've been following this thread, though not delving into the referenced links. However, I recall reading a very interesting article several years ago that helps explain (I think) some of the ambiguity in datasets. Sorry, I don't have a link...it is just something I read that stuck with me. I was confident of the source, however.

In nutshell - we aren't measuring the temperature of the planet...we are measuring the temperature at discrete points of the globe and extrapolating those measurements to cover a wide area. Decades ago those discrete points were far fewer than they are now, especially with satellite sampling.

One example is the weather station at an airport. In the 1940s or 50s when many airports were built they were far out in the countryside. They also formed the backbone of most of the official weather records. Today most of the those airports are now within the spitting distance of their host city, if not actually in the city. We know that temperatures in a city are affected by the city itself... the concrete, the pavement, the heat being put out by vehicles, air-conditioners, etc etc. And we know that the weather station at the airport is affected by this artificial city climate.

What we don't know is by how much the readings over the decades need to be adjusted. And this accounts for some of the occasional 'revisions' to the data over the years. It is too simple to extrapolate from a new station placed outside the city influence. The whole point of measuring over decades and decades is to be able to see what the temperature would have been in that spot over time. It is too simple to say come up with a formula for city growth over the decades since each weather station is affected differently. For example - I would hypothesize that the airport at Vancouver, BC will be affected far less than many other airports by Vancouver's growth because the airport is upwind of the city usually. On the hand the airport at Abbotsford BC is probably affected more than average during the summer because of the inversions that now occur.

So over time, scientists have recognized that the old data sets were not entirely accurate, and have revised them according to their better understanding of how different factors work. And then later on they revise them again when they better understand the factors. It's not fraudulent - it's just scientists trying to create a set of numbers that best reflect what is happening globally, and trying to strip out the sometimes very strong local factors.

imho, of course....
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Old Apr 20, 2013, 12:25 PM   #133
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Old Apr 20, 2013, 09:22 PM   #134
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Originally Posted by snberk103 View Post

So over time, scientists have recognized that the old data sets were not entirely accurate, and have revised them according to their better understanding of how different factors work. And then later on they revise them again when they better understand the factors. It's not fraudulent - it's just scientists trying to create a set of numbers that best reflect what is happening globally, and trying to strip out the sometimes very strong local factors.

imho, of course....
Berkeley Earth was created to explore this possible bias, and improve the estimates of temperature change. One of the founders (Richard Muller) was a vocal climate skeptic when the project started.

http://berkeleyearth.org/

Quote:

Summary of Results

Our ongoing research includes the study of climate variability, extreme events, and the role of the oceans.

A 2 page summary of our results to date, aimed primarily at the media, is available by clicking here.

More technical results, meant primarily for scientists, are presented below.
Global land temperatures have increased by 1.5 degrees C over the past 250 years

Berkeley Earth has just released analysis of land-surface temperature records going back 250 years, about 100 years further than previous studies. The analysis shows that the rise in average world land temperature globe is approximately 1.5 degrees C in the past 250 years, and about 0.9 degrees in the past 50 years.


Quote:

Berkeley Earth also has carefully studied issues raised by skeptics, such as possible biases from urban heating, data selection, poor station quality, and data adjustment. We have demonstrated that these do not unduly bias the results.

Human Effect

Many of the changes in land-surface temperature can be explained by a combination of volcanoes and a proxy for human greenhouse gas emissions. Solar variation does not seem to impact the temperature trend.
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Old Apr 21, 2013, 10:23 AM   #135
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Originally Posted by jnpy!$4g3cwk View Post
Berkeley Earth was created to explore this possible bias, and improve the estimates of temperature change. One of the founders (Richard Muller) was a vocal climate skeptic when the project started.
...
That's the strength of science. Berkeley Earth can claim that they've shown less bias due to station placements, etc and then publish. And now other scientists can look at the data and accept the results than can be replicated, and work to improve the results that can't be replicated - and the sum total of our understanding increases.

The one thing I am confident about is that this not the final word on this topic and that the numbers will continue to shift up and down.

And of course there is also the fuzziness introduced into their conclusions simply because scientists will have different starting assumptions.
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Old Jun 10, 2013, 09:57 AM   #136
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The World is Getting Warmer Faster Than Expected

How is that "stick you head in the sand" strategy working for you conservatives?

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The world is getting warmer faster than anticipated. A new report from the International Energy Agency says global temperatures will rise twice as fast as projected if countries don't act to slash their admissions soon. Released this morning, the IEA report shows carbon diaoxide from energy emissions rose 1.4 percent globally last year, a new record, and puts the world on pace for a 5.3 degree Celsius (9 degrees Fahrenheit) rise in global temperatures by 2020. In 2010, a UN summit agreed the goal would be to limit the rise in global temperatures to 2 degrees by 2020.
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