Thursday, June 11, 2009

target for tonight...

OK, time to make the rubble bounce. There's a nice online visualiser for climate data here, (thanks!) so we can have a lovely little chart.

OK, this shows the GISTEMP land-ocean mean for as long as they've been measuring, as the red line. As you can see, that sucker's going up. As you can also see, the variance is considerable - it bounces about quite a lot. The green line shows the trend. Over on the left, I've plotted trendlines starting 1998, dark blue, and 1999, purple.

As you can see, the hot year 1998 makes the trend look flatter over the next ten years - but it's still upwards, because this is a trend estimate, not just a line drawn from one end of the plot to the other. The computer wouldn't do anything that dishonest. But just to illustrate it, I've added a trend plot from 1992 to 2006, in light blue. Scary, huh? Going up like a rocket.

Of course it is; because it's completely meaningless. I selected those dates because 1992 was an unusual cold year caused by a volcanic eruption and 2006 was hot, which is no different to picking 1998 as a start point because it was hot.

If you do what Duff did, and forget that it is now 2009, as you can see from the chart, the trend in the last ten years would be going up FASTER than the trend across the whole dataset.

Someone arguing in good faith would have immediately dropped their sublime confidence at 0001Z 01/01/09 and started buying inland property, bullets, and toilet paper, to say nothing of apologising to the world at large.


David Duff said...

His volunteers all over the USA have gone to their local weather stations and sent in the photographs and now even the US authorities have admitted that a huge proportion of their sites used for the gathering of temperatures are, in effect, 'not fit for purpose'.

Now that is in the USA, a very peaceful and sophisticated society. Just use your imagination to guage how accurate the statistics are for the last century from, say, Russia or China or South America? Of course, our host's favourite guru, Dr. Hansen, assures us that his model computer codes take all that into account and smooth out any local anomalies. I don't know how because Dr. Hansen and his team, indeed no-one until Anthony Watts, has actually been to view these measuring devices upon which most of Hansen's global warming thesis is based.

More recently other scientists, recognising the difficulties of land-based weather stations have turned to satellites for basic data. They do not measure land temperatures, only atmospheric temperatures but they have the huge advantage of not being subject to any local distortions

(Just for absolute accuracy, our host being a little stickler, another set of 'scientists' attempted to use tree rings as a way of assessing very ancient temperatures and it was from their efforts that the infamous 'hockey stick' graph appeared and was seized upon by Hansen and the IPCC. Alas for them, Steve McIntyre at Climate Audit, despite the furious refusal of the 'scientists' concerned to reveal their methodologies, has over the years finally blown them away and broken their silly 'hockey stick' over their backs and demonstrated it to be a nonsense.)

So, my friends (and I include our spikey host) you have three choices before you in deciding what is likely to give you the nearest approximation to that mystical entity - average global temperature. The first - sea temperatures is really a non-starter so you are left with either land station readings (one of which is GISSTEMP, Dr. Hansen's own) or satellites. If you go here you will find a pretty little picture of the Univeristy of Alabama's satellite graph covering exactly - our host insists on exactutude, quite rightly! - the period covered by Dr. Hansen's apocalyptic forecast given to Congress in 1988. The result? Oh, it cooled slightly!

Finally (you will be plesed to read), our host insists on "trend lines". Well I've got the mother of all trend lines - it's called a Loess line - and no I haven't a clue what it means, but if you go here you will see a pretty picture of several of them for the same 20 year period and guess what, it shows either temperatures holding steady or cooling slightly.

Most sensible people would take one look at the complexity of this topic and realise that it is a judgment call. My judgment ('a poor thing but mine own') tells me that satellite data is infinitely preferable to surface data particlualry when the proponents of it refuse to release their computer codes!

Anonymous said...

The computer codes! All along, I knew it was the computer codes!

David Duff said...

You think it unimportant, 'Anon'?

Anonymous said...

Do you know what computer codes even are, 'Duffle?

David Duff said...

All I wish to know is whether or not they are important in your mind as far as this conversation is concerned. That's all!

Alex said...

You still haven't addressed anything in the posts. You have however continued to CTRL-C CTRL-V known liars Watt and McIntyre. This is the only computer code involved.

David Duff said...

And you, Alex, have failed to indicate whether or not you put more reliance on science based on ground station data, or on satellite data. It's very easy, all you have to do is take a couple of seconds and type 'ground' or 'satellite', then we'll know.

Alex said...

You are the one whose argument needs changes in fundamental physical constants to be right - a near-infallible marker of crackpottery.

Further, you are boring. Commenting on this blog is conditional on three criteria; you need to be interesting, true, or at least funny. So far you're 0 for 3, and I am going to delete anything else you send.

Neil said...

This thread, in video form:

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