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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Innovative work: Predicting rainfall with neural nets – Jennifer Marohasy

Predicting seasonal rainfall months ahead has surely got to be the Holy Grail of weather forecasting. Imagine the billions of dollars, the man-hours, and the anguish-prevented if we can do it. What if neural nets can be trained, validated, and used to help farmers, investors, and “Oi” — even Dam Managers?

Jennifer Marohasy and John Abbott were inspired to try a whole new approach to rainfall predictions after John’s car met a sad end in the infamous Brisbane flood. After five years work they’re keen to share the results, and their predictions. Check out those graphs below. The last one has a 3000 year range.

Read about how difficult it was for them to get useful data from the BOM, and how the BOM does not do proper benchmarking of their success rates. How serious are they? As usual, it’s those outside the stagnant pond of government approved science that are testing new ground. The government talks about innovation. Independent researchers do it.

***Jennifer Marohasy is speaking in Deniliquin NSW on Friday (tomorrow 6pm — details at the bottom)***.


She will be sharing the results of their research on using neural nets. How about this graph? That [...]

Rent-seekers reveal awful truth: Abbott wanted to investigate BOM data, Hunt opposed “due diligence”

Imagine the crime of trying to audit the BOM?

Last year, Graham Lloyd wrote in The Australian about how the BOM had made whopping two degree adjustments to data which turned cooling trends to warming trends and instead of improving the data, it created discontinuities. The BOM’s eventual explanation lamely exclaimed that the stations “might” have moved. (And they might not, too. Who knows, but remember this is what 95% certainty looks like.) Lloyd wrote about how historical records of extreme heat at Bourke had effectively been thrown in the trash. Who cares about historical records?

In response to the embarrassment and revealing questions, Tony Abbott wanted an investigation.  But Greg Hunt, and The Dept of Environment opposed the investigation and opposed doing “due diligence”. What are they afraid of? Instead, Hunt helped the BOM set up a one-day-wonder investigation with hand-picked statisticians that wasted another nine months before admitting that the BOM methods would never be publicly available or able to be replicated.  If it can’t be replicated, it isn’t science.

The BOM’s defense is always that their mystery method is considered “best practice” by other agencies around the world — who share the same incentives to exaggerate warming, [...]

The BOM: Homogenizing the heck out of Australian temperature records

There are adjustments on top of adjustments. Homogenised records are being used to correct raw records. Some man-made adjustments can infect data for miles around…

Rutherglen is a long running station in central Victoria. There are no documented site moves, but the long raw trend of slow cooling was adjusted up to a warming trend. What was cooling of 0.35C per century became a 1.7C warming trend.

Jennifer Marohasy, and others, have spent months trying to get answers from the BOM explaining why these massive adjustments were made. Excuses flowed. In the latest round, the BOM claim the changes are necessary to make the Rutherglen record match the trends in the neighboring stations. What the BOM doesn’t say is that there was no warming in the neighbours either,  not until after they were homogenized. The order in which stations are homogenized matters, which rather says something important about the arbitrary nature of the adjustments. Anomalous trends from far distant and poor locations can spread through waves of homogenization until better, longer stations succumb to political correctness and show the “correct” result. Small choices about which stations to to use first in the process can make a huge difference to the [...]

BoM Forum Panel: one-day-wonder. Rigorous as Annual Cakes and Tea Jamboree

Last August the BoM were feeling the heat — Graham Lloyd at The Australian and skeptics, particularly Jennifer Marohasy, were asking why cooling trends were being revised to warming trends at stations with no recorded moves. People were raising eyebrows at embarrassing questions about why the Bureau thought climate change was all-critical, yet they were tossing out historic Stevenson-screen data. The BoM felt so squeezed they finally answered some basic questions they’d been ignoring for years (like details on Rutherglen).

But the pressure kept growing because nobody needs a degree in Meteorology to know that there ought to be a reason for fiddling with historic thermometer data. The dumb punters were not impressed with the excuse that stations “might” have moved because tricky statistics on other stations 300km away detected an “unrecorded shift”. So the BoM and their apologist friends in The Dept of Environment dusted off a 3 year old idea called a Technical Advisory Forum, pulled out some names of respectable sounding statisticians and “voila” — created a one day wonder. The “technical forum” will spend more time releasing press releases than analyzing data.

On Jan 19th we were promised so much. The full gloss press release ticks [...]

The mysterious BOM disinterest in hot historic Australian Stevenson screen temperatures

When it comes to our rare high-quality historic records, and the real long term trends of Australian weather, the silence is striking. There are some excellent historical records of long term temperature data from the late 1800s in Australia, which lie underused and largely ignored by the BOM.

For the BOM, history almost appears to start in 1910, yet the modern type of Stevenson screen thermometer was installed across Australia starting as early as 1884 in Adelaide. Most stations in Queensland were converted as long ago as 1889 and in South Australia by 1892. Though states like NSW and Victoria were delayed until 1908.

Here’s a photo of the ones in Brisbane in 1890.

Brisbane was recording temperatures with modern Stevenson screens in 1890, as were some other stations, but the BOM often ignores these long records.

The BOM don’t often mention all their older temperature data. They argue that all the recordings then were not taken with standardized equipment. The BOM prefers to start long term graphs and trends from 1910 (except when they start in 1950 or 1970, or 1993).

The BOM was set up in 1908.  Before that there were Stevenson screens going in [...]

Big adjustments? BOM says Rutherglen site shifted, former workers there say “No”

The hot questions for the Australian Bureau of Meteorology (BOM) mount up. Rutherglen was one of the temperature recording stations that was subject to large somewhat mysterious adjustments which turned a slight cooling trend into a strongly warming one. Yet the official notes showed that the site did not move and was a continuous record. On paper, Rutherglen appeared to be ideal — a rare long rural temperature record where measurements had come from the same place since 1913.

The original cooling trend of  – 0.35C was transformed into a +1.73C warming after “homogenisation” by the BOM. To justify that the BOM claims that there may have been an unrecorded shift, and it was “consistent” with the old station starting  further up the slope before it moved down to the hollow.

Today retired scientist Bill Johnston got in touch with Jennifer Marohasy, with me and with Graham Lloyd of The Australian to say that he worked at times at Rutherglen and the official thermometer had not moved. It was always placed where it is now at the bottom of the hollow. That information has already made it into print in The Australian.

The original thermometer records suggest a [...]

BOM finally explains! Cooling changed to warming trends because stations “might” have moved!

It’s the news you’ve been waiting years to hear! Finally we find out the exact details of why the BOM changed two of their best long term sites from cooling trends to warming trends. The massive inexplicable adjustments like these have been discussed on blogs for years. But it was only when Graham Lloyd advised the BOM he would be reporting on this that they finally found time to write three paragraphs on specific stations.

Who knew it would be so hard to get answers. We put in a Senate request for an audit of the BOM datasets in 2011. Ken Stewart, Geoff Sherrington, Des Moore, Bill Johnston, and Jennifer Marohasy have also separately been asking the BOM for details about adjustments on specific BOM sites. (I bet Warwick Hughes has too). The BOM has ignored or circumvented all these, refusing to explain why individual stations were adjusted in detail.

The two provocative articles Lloyd put together last week were  Heat is on over weather bureau  and  Bureau of Meteorology ‘altering climate figures, which I covered here. This is the power of the press at its best. The absence of articles like these, is why I have said the media [...]

The heat is on. Bureau of Meteorology ‘altering climate figures’ — The Australian

Congratulations to The Australian again for taking the hard road and reporting controversial, hot, documented problems, that few in the Australian media dare to investigate.

How accurate are our national climate datasets when some adjustments turn entire long stable records from cooling trends to warming ones (or visa versa)? Do the headlines of “hottest ever record” (reported to a tenth of a degree) mean much if thermometer data sometimes needs to be dramatically changed 60 years after being recorded?

One of the most extreme examples is a thermometer station in Amberley, Queensland where a cooling trend in minima of 1C per century has been homogenized and become a warming trend of 2.5C per century. This is a station at an airforce base that has no recorded move since 1941, nor had a change in instrumentation. It is a well-maintained site near a perimeter fence, yet the homogenisation process produces a remarkable transformation of the original records, and rather begs the question of how accurately we know Australian trends at all when the thermometers are seemingly so bad at recording the real temperature of an area. Ken Stewart was the first to notice this anomaly and many others when he compared the raw data to [...]

Once in a life time opportunity to be an honest climate modeller — research scholarships!

This is a first! Announcing three scholarships for research-based higher degrees in Australia. Seeking Australian or New Zealand candidates who are science and engineering grads and interested in using neural nets to build climate models that work. This really is something new. Skeptical minds encouraged to apply. Please pass this on to people you think might be interested… – Jo

Once in a Life Time Opportunity to be an Honest Climate Modeller From Jennifer Marohasy

Most critics of anthropogenic global warming, and there are many, never get the opportunity to actually have a go at contributing to climate science in a practical or tangible and constructive way.  That is, they never get to pull a lever, press a button, build a model or make a forecast.  At best they might throw rotten tomatoes by way of blog posts and comments. This is because the tools of modern climate science are very complex and generally run on super computers with restricted access.

But what if it was possible to build your own climate model on a gaming computer, with some help from artificial neural network (ANN) technology?

Artificial neural networks are a form of artificial intelligence and machine learning, that can [...]

Don’t miss Jennifer Marohasy speaking in Sydney Wednesday

Jennifer Marohasy has been very involved in looking at Australian temperature data this year. She is speaking in Sydney on Wednesday about what she’s found. She’s talking about the new temperature dataset the BOM uses called ACORN, which they built after we asked them for an independent audit of their High Quality set.

Modelling Global Temperatures – What’s Wrong. Bourke & Amberley – as Case Studies

From Jennifer’s site: “The most extreme example that Ken found of data corruption was at Amberley, near Brisbane, Queensland, where a cooling minima trend was effectively reversed, Figure 1.” Jennifer has also raised her concerns (repeatedly) with Minister Greg Hunt.

Venue: The Gallipoli Club, 12 Loftus Street (between Bridge Street & Alfred Street), Sydney Time: 5.30 for 6pm

Additional Information: **Bookings from 11 June only **    BAR OPENS AT 5 PM – LIGHT REFRESHMENTS

Click here for info on how to book