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Statistical evidence of global warming ??

Here in Washington state, this is what we have noticed over the last few years:

Initially, nicer winters, drier, warmer, less snow
Subsequently, very wet years
Then lots of snow in winter
Then more extreme weather - either very cold or very hot, but OK on average
Also, rain changed from drizzle to heavy rain
Is the next step going to be drier and hotter, turning to semi-desert?

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Replies to This Discussion

Permalink Reply by LeRoy S Smith on September 12, 2009 at 2:44pm: Actually no there isn't..; ▶ Reply to This

Permalink Reply by DoonePlace on July 24, 2009 at 8:28am: Global Annual Mean Surface Air Temperature Change

Line plot of global mean land-ocean temperature index, 1880 to present. The dotted black line is the annual mean and the solid red line is the five-year mean. The green bars show uncertainty estimates. [This is an update of Fig. 1A in Hansen et al. (2006)]

Figure also available as large GIF, PDF, or Postscript. Also available are tabular data.

(Last modified: 2009-01-09)

Our traditional analysis using only meteorological station data is a lin e plot of global annual-mean surface air temperature change derived from the meteorological station network [This is an update of Figure 6(b) in Hansen et al. (2001).] Uncertainty bars (95% confidence limits) are shown for both the annual and five-year means, account only for incomplete spa tial sampling of data.

Figure also available as large GIF, PDF, or Postscript. Also available are tabular data.

(Last modified: 2009-01-09)

Annual Mean Temperature Change for Three Latitude Bands

Annual and five-year running mean temperature changes for three latitude bands that cover 30%, 40% and 30% of the global area. Uncertainty bars (95% confidence limits) are based on spatial sampling analysis. [This is an update of Figure 5 in Hansen et al. (1999).]

Figure also available as large GIF, PDF, or Postscript, Also available are table.

(Last Modified: 2009-01-09)

Annual Mean Temperature Change for Hemispheres

Annual and five-year running mean temperature changes for the northern ( red) and southern (blue) hemispheres.

Figure also available as large GIF, PDF, or Postscript, Also available are table.

(Last Modified: 2009-01-09)

Annual Mean Temperature Change for Land and Ocean

Annual and five-year running mean temperature changes for the land (gree n) and ocean (purple).

Figure also available as large GIF, PDF, or Postscript, Also available are tabular data.

(Last Modified: 2009-01-13)

Global Monthly Mean Surface Temperature Change

Line plot of monthly mean global surface tmperature anomaly. The black line shows meterological stations only; redle dots are the lan d-ocean temperature index, as described in Hans en et al. (1999). The land-ocean temperature index uses sea surface temperatures obtained from satellite measurements of Reynolds and Smith (1994).
[This is an update of Figure 8 in Hansen et al. (1999).]

Figure also available as large GIF, PDF, or Postscript. Also available are tabular data.

(Last modified: 2009-07-13)

Global Mean Surface Temperature vs. Year and Month

http://data.giss.nasa.gov/gistemp/graphs/; ▶ Reply to This

Permalink Reply by Steve Barbee on July 24, 2009 at 8:38am: Apparently, you are disputing the 0.9C drop from 2007 to Feb 2009 as shown by the Harris and Mann chart. You'll have to take that up with them. However, you do not dispute the fact that solar and natural geophysical changes are far stronger in influencing the global temperature than any perturbation caused by artifically-produced CO2.; ▶ Reply to This

Permalink Reply by LeRoy S Smith on September 12, 2009 at 2:45pm: Why do you use the least reliable data...(GISS) rather than the best?; ▶ Reply to This

Permalink Reply by Matt Coates on September 14, 2009 at 4:28am: LeRoy

What, in your opinion, is the "best" data?; ▶ Reply to This

Permalink Reply by DoonePlace on July 24, 2009 at 8:31am: No, but then that is a silly question by yourself. The amount of CO2 is not the only cause of temperature increases and decreases. The Carbon reservoir is gigantic.; ▶ Reply to This

Permalink Reply by DoonePlace on July 24, 2009 at 8:44am: You are missing a VERY IMPORTANT difference! Volcanic and Solar influence effects are transitory and eventually reverese themselves, plus they are out of our control. CO2 increases in the atmosphere, however, are long term, man induced and alter the temperature through the greenhouse effect. Look at climate model predictions for the next 100 years - we are in danger of catastrophic temperature increases.; ▶ Reply to This

Permalink Reply by LeRoy S Smith on September 12, 2009 at 2:54pm: Climate models in order to project catastrophic temperature increases must be primed with large "positive" feedback which is unproven to even exist....and the models showing the worst case sceneros are those with the greatest feedback. They also base their projections on the least reliable data set. The CO2 introduced by human activity is minute....sometime take a look at the actual numbers. 350ppm of CO2 is 3.5/10000th of the atmosphere...that is a pretty small number and human activity can't be shown to contribute more than 10% of that. Chasing CO2 as the "cause" of global warming is simply put, nonsense.; ▶ Reply to This

Permalink Reply by DoonePlace on September 12, 2009 at 3:24pm: As everyone should know most of the atmosphere is nitrogen and oxygen, pointing out that C02 is a small component is middle school science.; ▶ Reply to This

Permalink Reply by Andrzej Góralczyk on September 17, 2009 at 11:53am: 10% - is it big or small amount if we agree that the cause-effect relationship is not linear?

How are You sure that it is small?; ▶ Reply to This

Permalink Reply by DoonePlace on July 24, 2009 at 8:45am: Here is Keven Drum on the matter:

Global Warming Charlatanism

— By Kevin Drum | Thu July 23, 2009 2:57 PM PST

Ezra Klein is puzzled:

I've gotten a bunch of requests for a response to George Will's assertion that “If you’re 29, there has been no global warming for your entire adult life.” I'm actually puzzled enough by that comment to not really know how to respond.

Sigh. Here's the deal: Will is being cute. If you're 29, you became an adult in 1998, and average global temperatures last year were lower than they were in 1998. So: no global warming in your adult lifetime.

In case you've missed it, this is the new favorite talking point from the chucklehead denialist set. The earth is actually cooling! But as about a thousand serious climate researchers have pointed out, it's not true. Global temps have been trending up for over a century, but in any particular year they can spike up and down quite a bit. In 1998 they spiked up far above the trend line and last year they spiked below the trend line. So 2008 was cooler than 1998.

Of course, you can prove anything you want if you cherry pick your starting and ending points carefully enough. For example: The year 2000 was below the trend line and 2005 was above it. Temps were up 0.4°C in only five years! The seas will be boiling by 2050!

This is idiotic, and only deliberate charlatans who think they have an especially gullible audience bother with it. It's the trend line that matters, and the trend line has been going up for decades right along with rising CO2 concentrations. Listen to the climatologists, not the charlatans.; ▶ Reply to This

Permalink Reply by DoonePlace on July 24, 2009 at 8:46am: A study debunking the recent George Will article:

Compare-and-contrast reading on climate change

23 Jul 2009 11:12 pm
This morning George Will offered another in his series of reassuring columns about the overstated threat of climate change. Today's version:
"When New York Times columnist Tom Friedman called upon 'young Americans' to 'get a million people on the Washington Mall calling for a price on carbon,' another columnist, Mark Steyn, responded: 'If you're 29, there has been no global warming for your entire adult life. If you're graduating high school, there has been no global warming since you entered first grade.'
"Which could explain why the Mall does not reverberate with youthful clamors about carbon. And why, regarding climate change, the U.S. government, rushing to impose unilateral cap-and-trade burdens on the sagging U.S. economy, looks increasingly like someone who bought a closetful of platform shoes and bell-bottom slacks just as disco was dying."
Will presented the lack of youthful clamor as a sign of wholesome common sense. If you would like another way to think about the evidence, this one provided not by a columnist but by a physicist at UC Berkeley who has won a MacArthur grant, I recommend Richard A. Muller's book Physics for Future Presidents. I happened to read most of it on a long plane flight yesterday, so I was all set for Will's column today. So you can be ready before his next one appears, I recommend ordering the book now.

Muller is not at all in the most-alarmist group of climate scientists; indeed, he spends a lot of time explaining why he thinks Al Gore's Inconvenient Truth exaggerated the threat in several ways. You can see the beginning of his dissection of Gore's famous "hockey stick" chart of rising temperatures, which begins on page 292 of Muller's book, through a Google book-search excerpt here. (The hockey stick, below)

Muller says that the evidence behind the hockey-stick chart is wrong. (Read it yourself to see why.) "In fact, much of what the public 'knows' about global warming is based on distortion, exaggeration, or cherry picking," he says, adding:
"An example of distortion is the melting of the Antarctic ice -- something that actually contradicts the global warming model but is presented as if it verifies them. Exaggeration includes the attribution of Hurricane Katrina to global warming, even though there is no scientific evidence that they are related. Cherry picking is the process of selecting data that verify the global-warming hypothesis but ignoring data that contradict it."
The real purpose of his book is to set out as clearly as possible the way scientists approach the inevitably-conflicting evidence on big public policy issues like climate change (or the real risks of terrorism, or dealing with nuclear waste). Before the Iraq war, it would have been useful for intelligence officials to set out the way they balance their version of inevitably-conflicting and always-incomplete facts. Muller sets out the way climate scientists weigh the evidence pro and con concerning climate change and the probabilities for each explanation.

By the end of the process he has forcefully re-established the principle that real scientists view propositions as most convincing when all the doubts, caveats, and contrary bits of evidence are admitted -- whereas politicians and the public want to hear an all-or-nothing verdict with no hems or haws. Consistent with this approach, it is all the more powerful when Muller concludes that there really are reasons to worry about man-made climate change. He also provides guidelines about sensible and fanciful ways to deal with the problem. I am not equipped to judge this argument on purely scientific grounds; but the book is addressed to lay readers and is convincing in what it says about the process of scientific reasoning. If this latest George Will opus serves to drive readers to Muller's book, it will have done some good.; ▶ Reply to This