For those interested in the theory that upper atmosphere inflow of moisture from the Indian Ocean is a major determinant of rain in Australia, check out the satellite loop for the last 4 hours right now.
Here is the development of the inflow over the last few days.
Note this is in the presence of a high pressure system with an upper atmosphere ridge and trough, as can be seen by the slight deformation of the isobars over Queensland.
Ken Stewart is engaged in the first ever independent study of the complete High Quality Australian Site Network. Ken has a series of posts, the first including a lot of background information and explanation. Subsequent posts are not be as long and part 6, the data from the Victorian sites has just been done.
Like many people, he thought that the analysis of climate change in Australia, and information given to the public and the government, was based on the raw temperature data. He was wrong. He averaged maxima and minima for all stations at each site, then compared the result with the High Quality means. By these calculations (averaging the trend at each site in Victoria) the raw trend is 0.35 degrees C per 100 years, and the High Quality state trend is 0.83C. Thatâ€™s a warming bias of 133%!
Corrected the page-proofs of my drought paper today.
CRITIQUE OF DROUGHT MODELS IN THE AUSTRALIAN DROUGHT EXCEPTIONAL CIRCUMSTANCES REPORT (DECR)
This paper evaluates the reliability of modeling in the Drought Exceptional Circumstances Report (DECR) where global circulation (or climate) simulations were used to forecast future extremes of temperatures, rainfall and soil moisture. The DECR provided the Australian government with an assessment of the likely future change in the extent and frequency of drought resulting from anthropogenic global warming. Three specific and different statistical techniques show that the simulation of the occurrence of extreme high temperatures last century was adequate, but the simulation of the occurrence of extreme low rainfall was unacceptably poor. In particular, the simulations indicate that the measure of hydrological drought increased significantly last century, while the observations indicate a significant decrease. The main conclusion and purpose of the paper is to provide a case study showing the need for more rigorous and explicit validation of climate models if they are to advise government policy.
Meanwhile, scientists are finding new ways to communicate worthless forecasts to decision makers.
These models have been the basis of climate information issued for national and seasonal forecasting and have been used extensively by Australian industries and governments. The results of global climate models are complex, and constantly being refined. Scientists are trialling different ways of presenting climate information to make it more useful for a range of people.
Conducting professional validation assessment of models would be a start, followed by admitting they are so uncertain they should be ignored.
Anthony’s Tour continues at a breakneck pace this week — with only four venues to go.
The talks at Emerald that I organized went quite well, considering this is a small regional town. About 80-100 people attended an teaser session during the Property Rights Australia meeting during the day, and around 40 attended at night. We got a standing ovation during the day — the first time for me! The crowd was a mixture of ages and sexes and I think messages of bureaucratic sloth and opportunism resonated with them. Central Queensland turned on one of its trademark sunsets for Anthony:
It was good to spend a bit of time with Anthony and catch up on the goss — well not really gossip, but about bloggers and the people behind the curtain. You know how it is, you tend to get a certain view of the people involved, but when you learn more about them, it turns out they are just regular people who put their hand up for something they believe in.
The ‘strongest male’ is itself a highly variable component.
How to formalise this as a niche? Preamble. All we have, really, are observations. To put niches into a statistical framework, we only have the expected distributions of those observations (both singly and jointly). Selection (either natural or through our study design) changes the distribution of features, and we observe those changes.
For example, if the sample of breeding males is generally taller than the population of breeding males, then we could presume there is selective pressure on this feature — an important item of information. This could be detected statistical significant (e.g. the distribution differ in a Chiâ€“squared test).
A couple of questions from the last nichey post prompted this post. Geoff said that:
I’m not even sure what is meant by an optimal environment for a species/genus/whatever.
while Andrew said that:
it wouldn’t surprise me if a lot of species tend to live at the margins of their “ideal” habitat.
We need a bit of abstraction to address these questions. In a laboratory, a plant would be expected to show a humped response to the main variables of temperature and water availability. The parameterisation of this function can be termed the ‘fundamental niche’ of the species, and may be equated with a physiochemical optimum unaffected by competition.
Having just returned from my leg of the tour, I have been offline for awhile, but expect to catch up this week. Here is my powerpoint presentation “Tweeter and the Monkey M(e)an — Negating Climate Change Policy” (4.3MB).
The title comes from a song by the Traveling Wilburys. The message is that without proper validation, climate models are no more credible than Tweets, and from my (and others’) validation testing, the model forecasts are not fit-for-forecasting, showing no more accuracy than the “Monkey Mean” — the average temperature and rainfall. I critique CSIRO and BoM reports and conclude with an example of how to make rational business decisions under climate forecast uncertainty.