JoNova

A science presenter, writer, speaker & former TV host; author of The Skeptic's Handbook (over 200,000 copies distributed & available in 15 languages).


The Skeptics Handbook

Think it has been debunked? See here.

The Skeptics Handbook II

Climate Money Paper


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GoldNerds

The nerds have the numbers on precious metals investments on the ASX



Has CO2 warmed the planet at all in the last 50 years? It’s harder to tell than you think.

Joint Post: Jo Nova and Tony Cox

Even most skeptics agree that the world has been warming during the last 50 years, but there is apparently no significant underlying warming trend in 46 out of 47 years of data. Something decidedly unusual happened to the world in 1977 and we don’t know for sure what it was. The world got warmer, and the change “stuck”. But there were no extra emissions of CO2 in that year, so there is no reason to pin this to CO2.

It’s difficult to believe we are not sure – but the last 50 years of warming trend depends on that single stepwise leap in 1977. Look at the graph below. Does it show one strong underlying warming trend, or is it really a trend so insignificant that it wouldn’t exist if there was not a step change that artificially bolstered it?

A series of two flat lines can appear to be a continuous warming trend if a linear trend line is fitted because it ignores the step change.  McKitrick and Voselgang

This step effect was first noted by David Stockwell in 2009

The continuous warming appears to be obvious in the records of [...]

Thorne 2010: A very incomplete history of the missing hot spot

Emails are coming in about the latest attempt to announce that they’ve “found the hot-spot”: Thorne et at 2010.

It’s already being used in NOAA press releases to repeat the same line about how a “new scientific study” supports the models. The aforementioned support is rather weakly phrased as being “broadly consistent” (which somehow means the same thing as being “90% certain” a catastrophe is on the way, right?).

But it gives them another chance to claim it’s been found:

This new paper extensively reviews the relevant scientific analyses — 195 cited papers, model results and atmospheric data sets — and finds that there is no longer evidence for a fundamental discrepancy and that the troposphere is warming.

It says something about how important the hot spot is that they keep “finding it”. (Even though they never seem to issue a press release saying it’s missing.) But since the data from the last warming spell came in ten years ago, there are only so many ways they can rehash the same numbers. So now they’re scraping the bottom of the barrel in desperation. This new study is not a “new scientific study”, it’s a new review. This paper tells us [...]

The models are wrong (but only by 400%)

This is one humdinger of a paper and it’s been a long time coming. It’s a big step forward in the search for the hot-spot. (If the hot spot were a missing person, McKitrick et al have sighted a corpse.) In 2006 the CCSP quietly admitted with graphs (in distant parts of various reports) that the models were predicting a hot spot that the radiosondes didn’t find (Karl et al 2006). Obviously this was a bit of a problem for the Scare Campaign. Much of the amplifying feedback created in the models also creates the hot-spot, so without any evidence that the hot-spot is occurring, there goes the disaster (and the urgent need for funding and junkets). Douglass et al officially pointed out the glaring deficiency in 2007. Santer et al replied in 2008 by discovering a lot of uncertainties, and stretching the error bars. Since the broad errors bars overlapped he could announce that the hot spot wasn’t really missing (even though he didn’t really find it either). He wrote this up in words effectively saying that the inconsistency in temperatures was not so inconsistent. McIntyre and McKitrick pointed out these key Santer results which used data up to 1999 were overturned with the use of data up to 2009. Somehow, despite all the excitement over Santer et al 2008, the IJOC decided updating it and contradicting it was “not interesting” and it took months to reach that banal conclusion. [...]

Unscientific hockey sticks and hidden data

These maps and graphs make it clear just how brazenly unscientific the Hockey Stick is.

It’s clear that the world was warmer during medieval times. Marked on the map are study after study (all peer-reviewed) from all around the world with results of temperatures from the medieval time compared to today. These use ice cores, stalagmites, sediments, and isotopes. They agree with 6,144 boreholes around the world which found that temperatures were about 0.5°C warmer world wide.

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