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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Hottest July in 4000 years? Not even the hottest July since *2014* according to satellites

NOAA has a press release out being picked up around the world. For example, the DailyMail, UK, is saying July was the hottest month since records began in 1880 as heatwaves swept the Earth’s countries and oceans. Other silly tabloids have headlines about this being the hottest July in 4,000 years, as if we have even the remotest idea what the average July global temperature was in the days of Plato.

Better data shows July this year is the hottest since way back in…  2014. It’s not 4,000 years, not 135 years, it’s the hottest July since the last one. We only have 30 years of good climate data: the satellites tell us the pause is real, and last month’s summer temperatures is not a record anything. According to the UAH and RSS global satellites, lower troposphere averages for July 2014 were 0.30C and 0.34C, compared to July 2015 of 0.28C. Even, June 2015 was hotter (UAH, 0.35C; RSS, 0.39C). July 2015 is not even the hottest month since June.

But some journalists will believe anything. Anthony Sharman, sports journalist,, Australia, thinks we know the global temperature of the July that Jesus was born. Who’s a gullible journalist then? [...]

Charles Sturt’s time: so hot that thermometers exploded. Was Australia’s hottest day in 1828? 53.9C!

Australia’s hottest day? Not 2010, but 1828 at a blistering 53.9 °C

Back before man-made climate change was frying Australia, when CO2 was around 300ppm, the continent savoured an ideal preindustrial climate, right? (This is the kind of climate we are spending $10bn per annum to get back too?)

We are told today’s climate has more records and more extremes than times gone by, but the few records we have from the early 1800’s are eye-popping.  Things were not just hotter, but so wildly hot it burst thermometers.  The earliest temperature records we have show that Australia was a land of shocking heatwaves and droughts, except for when it was bitterly cold or raging in flood.

In other words, nothing has changed, except possibly things might not be quite so hot now.

Silliggy (Lance Pidgeon) has been researching records from early explorers and from newspapers. What he has uncovered is fascinating. — Jo


Charles Sturt  (1930 postage stamp) Wikimedia

Lance Pidgeon writes:


These Australian headlines from the 1800′s above describe extremes the early colonists faced. At the time the European explorers who were instructed and equipped to [...]

Has North Victoria cooled, and is that the ghost of a solar cycle signal we see?

UPDATED AGAIN #4 — Now with Vukcevics Hale cycle graph of Echuca.  and #3  David Archibalds suggestion of the Hale Cycle at work. #2 with Willis Eschenbach’s graph and my thoughts, (see below)

Ian Bryce sent me a striking graph (or two). Looking at the original raw data from Echuca Victoria shows a dramatic cooling trend of nearly half a degree since 1900, and rather than being a siting anomaly, it’s repeated in two towns about 100km away.

Curiously he also finds peaks in the maximums at Echuca that look for all the world like they match the solar cycle. Is it a fluke, or could it be real?  If it’s real, what conditions make the solar sun-spot cycle so apparent in Echuca — where its maximum temperatures seemingly peak with each second solar cycle. Can anyone find this signal in other places? — Jo


The area is inland Northern Victoria

Has there been Global Warming or Global Cooling in Echuca

Guest post: Ian Bryce

I have spent about 37 years working with processing tomatoes in the Goulburn Valley in Australia, and the last 25 years or so, with research into growing and processing canning tomatoes. Since 1984, our [...]

Threat of ANAO Audit means Australia’s BOM throws out temperature set, starts again, gets same results

Joanne Nova and Ken Stewart

A team of independent auditors, bloggers and scientists went through the the BOM “High Quality” (HQ) dataset and found significant errors, omissions and inexplicable adjustments. The team and Senator Cory Bernardi put in a Parliamentary request to get our Australian National Audit Office to reassess the BOM records. In response, the BOM, clearly afraid of getting audited, and still not providing all the data, code and explanations that were needed, decided to toss out the old so called High Quality (HQ) record, and start again. The old HQ increased the trends by 40% nationally, and 70% in the cities.

So goodbye “HQ”, hello “ACORN”. End result? Much the same.

That meant the ANAO could avoid an audit, since the BOM had changed data-sets, the point of auditing the old set was moot.

For me, this version is so much worse than the previous one. In the HQ data set the errors could have been inadvertent, but now we’ve pointed out the flaws, there can be no excuses for getting it wrong. Instead of fixing the flaws (and thanking the volunteers), it’s almost as if they’ve gone out of their way [...]

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 [...]

Australian temperature records shoddy, inaccurate, unreliable. Surprise!

The BOM say their temperature records are high quality. An independent audit team has just produced a report showing that as many as 85 -95% of all Australian sites in the pre-Celsius era (before 1972) did not comply with the BOM’s own stipulations. The audit shows 20-30% of all the measurements back then were rounded or possibly truncated. Even modern electronic equipment was at times, so faulty and unmonitored that one station rounded all the readings for nearly 10 years! These sloppy errors may have created an artificial warming trend. The BOM are issuing pronouncements of trends to two decimal places like this one  in the BOM’s Annual Climate Summary 2011 of “0.52 °C above average”  yet relying on patchy data that did not meet its own compliance standards around half the time.  It’s doubtful they can justify one decimal place, let alone two?

We need a professional audit.


A team of independent engineers, scientists, statisticians and data analysts (brought together by the joannenova blog) has been going through the Australia Bureau of Meteorology records (BOM). They’ve audited some 8.5 million daily observations across 237 High Quality and other close sites in Australia. Shockingly, while [...]

Messages from the global raw rural data. Warnings, gotcha’s and tree ring divergence explained!

Have you wondered what the global raw rural data tells us?

What did those thermometers say before the adjustments, smoothing, selection, and averaging?

This just might be the first time anyone has publicly compared the global raw data to published adjusted data sets in this way.

Frank Lansner has been dedicated in the extreme, and has developed a comprehensive Rural Unadjusted Temperature Index, or RUTI. One of the most interesting points to come out of this extensive work is the striking difference between coastal stations and inland stations. Frank kept noticing that the trend of the inland stations was markedly different from coastal stations and island stations.

Fig1. Red-Blue lines mark regions where there was a different coastal to inland trend. In green areas the two trends were similar.

What he finds is perhaps not so unusual: The coastal areas are heavily influenced by the sea surface temperature. Inland stations record larger rises and falls in temperature, which is hardly surprising. But, the implications are potentially large. When records from some stations are smoothed over vast distances (as in 1200 km smoothing), results can be heavily skewed by allowing coastal trends to be smoothed across inland areas. What Lansner [...]

Was 2010 the hottest ever?

Was 2010 “the hottest year ever” as the PR machine repeats ad nauseum? Yes — but only if you ignore three of the four main global datasets and those awkward questions about why nobody thought to put thermometers in better places.

Run your eyes down this page to see how the GISS temperatures pan out compared to all the other compilations. This is James Hansen’s group, and GISS stands for the Goddard Institute of Space Studies — and in the topsy-turvey world of climate change, that’s apt — the space centre and hot bed of rocketry calculates world temperatures by ignoring  … satellites. For GISS, measuring the world temperature, calls for irregularly spaced, unique, non-standardized temperature stations (sometimes near air-conditioning vents and concrete). And no sir, not the satellites that scan the Earth 24 hours a day, over land and sea, and which are usually not too close to exhaust vents, or buildings, or (thank goodness) fermenting vats of sewage either.

So, indeed, the only sane answer to the cherry picking crowd who crow triumphantly about their outlying most favorite result, is that “No” 2010 was not hotter than 1998, not according to the satellites. And even if it had [...]

Announcing a formal request for the Auditor General to audit the Australian BOM

A team of skeptical scientists, citizens, and an Australian Senator have lodged a formal request with the Australian National Audit Office (ANAO) to have the BOM and CSIRO audited.

The BOM claim their adjustments are “neutral” yet Ken Stewart showed that the trend in the raw figures for our whole continent has been adjusted up by 40%. The stakes are high. Australians could have to pay something in the order of $870 million dollars thanks to the Kyoto protocol, and the first four years of the Emissions Trading Scheme was expected to cost Australian industry (and hence Australian shareholders and consumers) nearly $50 billion dollars.

Given the stakes, the Australian people deserve to know they are getting transparent, high quality data from the Bureau of Meteorology (BOM). The small cost of the audit is nothing in comparison with the money at stake for all Australians. We need the full explanations of why individual stations have been adjusted repeatedly and non-randomly, and why adjustments were made decades after the measurements were taken. We need an audit of surface stations. (Are Australian stations as badly manipulated and poorly sited as the US stations? Who knows?)

Australian Temperatures in cities adjusted up by 70%!?

Ken Stewart has been hard at work again, this time analyzing the Australian urban records. While he expected that the cities and towns would show a larger rise than records in the country due to the Urban Heat Island Effect, what he found was that the raw records showed only a 0.4 degree rise, less than the rural records which went from a raw 0.6 to an adjusted 0.85 (a rise of 40%). What shocked him about the urban records were the adjustments… making the trend a full 70% warmer.

The largest adjustments to the raw records are cooling ones in the middle of last century. So 50 years after the measurements were recorded, officials realized they were artificially too high? Hopefully someone who knows can explain why so many thermometers were overestimating temperatures in the first half of the 1900′s.

50 years later?

The raw Australian urban temperature records are in blue. The adjusted records in red. Note that temperatures in the middle of last century appear to be adjusted downwards. These are the annual average recordings for all 34 sites.

Remember Dr David Jones, Head of Climate Monitoring [...]