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



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Homogenisation: The Magical system which uses thermometers in Victoria to correct the temperature in Tasmania

Trying to fix past mistakes through homogenization

Lots of things can muck up a perfect thermometer spot, like shade, new roads, new screens, or old paint. In order to remove these annoying non-climatic effects, the BOM compares each station to those around it to look for odd changes. In theory this sounds like a good idea. In practice it’s more like hepatitis – bad news that spreads. It’s a rogue code, sweeping through records, trying to find undocumented changes, and enabling any amount of revisionism.

The BOM “detects” these mysterious shifts at each site through thermometers that may be hundreds of kilometers away, even across a mountain range or the Bass Strait.

Among other sites, Cape Bruny in far south Tasmania has been corrected with the help of Ballarat 812 km away on the mainland, over mountains and across the Bass Strait. In 1991 Cape Bruny was found to be “statistically” wrong, and adjusted down by over half a degree.

All these sites marked in red were used to correct the record at least once at Cape Bruny, a distant island in the far south of Tasmania.

It’s a tough life for old screens: Their wooden houses get [...]

#DataGate! First ever audit of global temperature data finds freezing tropical islands, boiling towns, boats on land

What were they thinking?

The fate of the planet is at stake, but the key temperature data set used by climate models contains more than 70 different sorts of problems. Trillions of dollars have been spent because of predictions based on this data – yet even the most baby-basic quality control checks have not been done.

Thanks to Dr John McLean, we see how The IPCC demands for cash rest on freak data, empty fields, Fahrenheit temps recorded as Celsius, mistakes in longitude and latitude, brutal adjustments and even spelling errors.

Why. Why. Why wasn’t this done years ago?

So much for that facade. How can people who care about the climate be so sloppy and amateur with the data?

HadCrut4 Global Temperature, 1850 – 2018.

Absurdity everywhere in Hadley Met Centre data

There are cases of tropical islands recording a monthly average of zero degrees — this is the mean of the daily highs and lows for the month. A spot in Romania spent one whole month averaging minus 45 degrees. One site in Colombia recorded three months of over 80 degrees C. That is so incredibly hot that even the minimums there were [...]

BOM homogenization errors are so big they can be seen from space

It’s just not cricket. And in so many ways.

Shame to let a perfectly good dataset go to waste… Australian data comes from some of the longest stations running in the Southern Hemisphere; it could be useful. Instead we get more evidence here that the BOM’s magical and secret homogenization adjustments can take poor data and spread false signals into better data. Homogenisation errors are already visible in a site-by-site analysis, but this shows the problems may be so big they affect averages across the whole of Australia, and we can detect them with satellites.

Tom Quirk continues comparing the satellite record of Australia with the BOM surface version. Previously, he (and for the record, Ken Stewart in 2015) showed that some discrepancies are due to the effect of heavy rain or drought. But now he looks further and finds that not-so-coincidentally, the largest gaps and most “inexplicable” differences occur in the mid nineteen-nineties, the same years the BoM shifted from using old large Stevenson screens to electronic thermometers. Around the same time, the large screens were often also swapped for much smaller ones too — like double jeopardy for data. Oddly, spookily, the BOM makes many adjustments to data [...]

Bourke: How 1km of land clearing can warm a million square miles

Yet again, we have to ask: does the Bureau of Meteorology care about Australia’s long term climate trend? Are they even trying?

Bourke could be one of the top ten most influential temperature sites in the world, mostly by virtue of being miles from anywhere, and used to homogenize a large slab of the land mass of Australia. Bill Johnston documents how changes to the site create most of the temperature trend.

The Bureau of Meteorology’s fancy magical and secret homogenization protocol does not detect changes that obviously affect the temperature (like the clearing in the photo below). But sometimes the BoM make “corrections” because of site changes that don’t appear to have mattered. Is it conveniently selective or just inept?

The BoM don’t even document major site changes a lot of the time. Even iconic sites that affect huge areas are badly managed. Someone got the tractor and plough and cleared the vegetation. As usual, a citizen scientist, a volunteer, documents it (along with a suite of other site changes).

In the last ten years land was cleared around the thermometer. This denuded area has a lower humidity, and higher volatility of temperatures. The data from this thermometer [...]

Scandal: BoM ignores major site changes at iconic, historic, Sydney Observatory. Sloppy or deliberate?

Australia’s oldest and most iconic site has changed dramatically, but major site changes are not even being recorded.

The way the Bureau of Meteorology (BoM) treat this site says a lot about the unscientific, shoddy, biased standards it uses at sites everywhere. This was their headquarters. Experts walked past new walls, construction and highways, yet they didn’t record them? Beggars belief.

Just as Peter Ridd warns us that we can’t trust some marine and reef institutes, Bill Johnston is the whistle-blower warning us about the Bureau of Met. There is no law of science that says human institutes are infallible. When they run off the rails, how do we find out? Ridd issued a warning from the inside and ended up in the Federal Court. When people, like Bill write from the outside, the BoM waves the peer-review gatekeeper, and anonymous reviewers can easily shut that gate, and without any penalty.

The louvered thermometer house in front of the Observatory in 1864. (Courtesy of the State Library of NSW.)

Sydney Observatory is one of the longest running stations in the Southern Hemisphere, starting in 1859. It was Australia’s premier meteorology site and in the 1800′s it was known [...]

Another BOM scandal: Australian climate data is being destroyed as routine practice

Historic climate data is being destroyed

The Bureau have a budget of a million dollars a day, but seemingly can’t afford an extra memory stick to save historic scientific data.

In the mid 1990s thermometers changed right across Australia — new electronic sensors were installed nearly everywhere. Known as automatic weather sensors (AWS) these are quite different to the old “liquid in glass” type. The electronic ones can pick up very short bursts of heat – so they can measure extremes of temperatures that the old mercury or liquid thermometers would not pick up, unless the spike of heat lasted for a few minutes. It is difficult (impossible) to believe that across the whole temperature range that these two different instruments would always behave in the exact same way. There could easily be an artificial warming trend generated by this change (see the step change in the graphs). The only way to compare the old and new types of thermometer is to run side by side comparisons in the field and at many sites. Which is exactly what the bureau were doing, but the data has never been put in an archive, or has been destroyed. It’s not easily available [...]