Attributed to NEIL BROWN, December 26, 2009
UNLIKE most people, who think Copenhagen was a failure, I think it was a great success. It has preserved the golden rule of international diplomacy.
Years ago, when I was a young fellow and started to go to international conferences, an old hand who was about to retire took me aside. ''I'll be shoving off into retirement soon,'' he said, ''so I thought I might pass on the golden rule of international conferences."
I was fascinated. I was sure he would Read more [...] 3 com
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 Read more [...] 5 com
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 Read more [...] one
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 Read more [...] none
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 Read more [...] 21 com
Virial Paper 6_12_2010 submitted by Adolf J. Giger.
Allow me to make some more comments on the Virial Theorem (VT) as used by Ferenc Miskolczi (FM) for the atmosphere.
As I said on this blog back in February, a very fundamental derivation of the VT was made by H. Goldstein in Section 3-4 of "Classical Mechanics", 1980, Ref. : PE= 2*KE (potential energy=2 x kinetic energy). Then, he also derives the Ideal Gas Law (IGL), P*V = N*k*T as a consequence of the VT, and shows that PE=3*P*V and KE=(3/2)*N*k*T. Read more [...] 21 com
My rebuttal of Thomasâ€™ computer models of massive species extinctions has been mentioned in a statement by Sen. Orrin G. Hatch before the United States Senate, on June 10, 2010.
1. Stockwell (2000) observes that the Thomas models, due to lack of any observed extinction data, are not â€˜tried and true,â€™ and their doctrine of â€˜massive extinctionâ€™ is actually a case of â€˜massive extinction bias.â€™
[Stockwell, D.R.B. 2004. Biased Toward Extinction, Read more [...] none
Ferenc sent out reprints of his upcoming manuscript, and graciously acknowledges the contribution of a number of us for support, help and encouragement. I particularly like the perturbation and statistical power analysis, checking that a change in the greenhouse effect due to CO2 would likely have been detected if it had been present in the last 61 years.
The Stable Stationary Value of the Earth's Global Average Atmospheric Planc-weighted Greenhouse-Gas Optical Thickness
by Ferenc Miskolczi,
Energy Read more [...] 14 com
Problem 4. Why has a community of thousands or tens of thousands of climate scientists not managed to improve certainty in core areas in any significant way in more than a decade (eg the climate sensitivity caused by CO2 doubling as evidenced by little change in the IPCC bounds)?
This problem has been the hardest, probably because it takes enormous hubris to claim solution to a problem that defeats thousands of usually intelligent people. One man who does that is -- Dr Roy Spencer -- claiming a Read more [...] 9 com
Sceptic - from the Greek skeptikos one who reflects upon, from skeptesthai to consider.
Scepticism is variously described as a doubting or questioning attitude, a person who uses their mind creatively, or even someone who demands physical evidence in order to be convinced (especially when this demand is out of place).
To consider carefully with regard to evidence is the professional way to approach public affairs, or matters of considerable importance -- the opposite of sloppy, credulous, reckless Read more [...] one
Is the anthropogenic climate change controversy just an episode in an ongoing drama, and if so what is the main theme?
The Catallaxyfiles in RSPT in la la land review a number of biting newspaper editorials on the Resource Super Profits Tax (RSPT), providing a possible answer by replacing a few words.
Funny thing is, Garimpeiro does not think the government and its Treasury [IPCC] advisers actually know that they have been practising deceptions. Itâ€™s more a case of them not having an even Read more [...] 2 com
Will a 40% tax on mining profits increase government revenue from the sector?
If you apply the theoretical perspective of Hauser's Law, maybe not. Hauser's Law is based on an empirical observations that no matter what the tax rates have been, in postwar America tax revenues have remained at about 19.5% of GDP.
It easy to see that constant revenue, whatever the tax rate, could give rise to the niche-like Laffer curve, a humped distribution where rates of taxation above or below an optimal rate Read more [...] none
Problem 2. Cointegration was developed in economics to deal with a problem of spurious correlation between series with stochastic trends. Why should spurious correlation be a concern if the trends in temperature and GHGs are deterministic?
Sometimes I've been accused of over-simplifying, but I do try to make models as simple as possible, because it avoids a lot of speculation. With that view, this simple model represents paradoxical features of unit roots. Even if there was a deterministic relation Read more [...] 9 com
Problem 5. Why do most of the forecasts of climate science fail?
If climate science had a history of accurate forecasts, it would have a foundation for greater credibility. That is what is expected in other fields. Instead, it is "denialist" to say that climate science has a lousy record of predictions.
When I started analysing ecological models in my doctoral studies, it wasn't ideologically unsound to say that the models did a lousy job, and I spent 3 years trying to work out why. Wouldn't Read more [...] 35 com
Problem 3. Why is the concept of â€˜climateâ€™ distinguished from the concept of â€˜weatherâ€™ by an arbitrary free parameter, usually involved in averaging or smoothing or â€™scaleâ€™ transformations of 10 to 30 years?
The recent article on Question #9 by Meiers and response by Stephen Goddard used a coin toss analogy to answer this question. Meiers states that while the uncertainty of the probability of heads in the short term is high, over the long term we expect Read more [...] 17 com
Problem 1. If temperature is adequately represented by a deterministic trend due to increasing GHGs, why be concerned with the presence of a unit root?
Rather than bloviate over the implications of a unit root (integrative behavior) in the global temperature series, a more productive approach is to formulate an hypothesis, and test it.
A deterministic model of global temperature (y) and anthropogenic forcing (g) with random errors e is:
An autoregressive model of changes in Read more [...] 119 com
Prompted by the interest VS has rekindled in fundamental analysis of the temperature series at Bart's and Lucia's blogs, below are a small set of core 'problems' facing statistical climate science (CS) -- kind of a challenge.
Remember a deterministic trend is one brought about by a changing value of the mean, due to a change in an equilibrium value for example (ie non-stationary). A stochastic trend is due the accumulation of random variations; all parameters are stationary.
Problem 1. If temperature Read more [...] 2 com
So now the fun starts. We have established the integration order of the variables in the RadF file, we impose the rule that only variables of the same order can be combined, and in particular that they cannot be cointegrated with temperature which is I(1). In this case all the anthropogenic variables in RadF are I(2) -- W-M_GHGs, O3, StratH2O, LandUse, SnowAlb, BC, ReflAer, AIE -- while Solar and StratAer are I(1) or I(0).
Adding these AGW variables together would be one way, as they are Read more [...] 38 com
The test of integration order from the previous post is applied to the major atmospheric forcings used in the GISS global climate models in recent years. These are available for 1880 to 2003 in a file called RadF.txt The codes for the forcings are self explanatory: W-M_GHGs, O3, StratH2O, Solar, LandUse, SnowAlb, StratAer, BC, ReflAer, AIE.
Below is the sum of the forcings.
We want to know the integration order of the global surface temperature series as well. The result:
Temp=1, Read more [...] 27 com
I try not to pen editorials. OK here goes. I respect the attention given to this blog, as there are plenty of other great blogs on climate change, politics, finance, etc to read. I try to stay an 'on message' advocate for numeracy. Everyone has something to offer from their experiences though. Right at this moment, there is something to say that is important about numeracy, but takes a bit to explain.
I would encourage y'all to read the discussion on New paper on mathematical analysis of GHG Read more [...] 60 com
Please discuss the new paper by Michael Beenstock and Yaniv Reingewertz here.
Way back in early 2006 I posted on an exchange with R. Kaufmann, whose cointegration modelling is referenced in the paper, entitled Peer censorship and fraud. He was complaining at RealClimate about the supression of these lines of inquiry by the general circulation modellers. The post gives a number of examples that were topical at the time. ClimateGate bears it out.
Steve McIntyre wrote a long post on the affair here.
[R]ealclimateâ€™s Read more [...] 73 com
Deserving of wider attention: Ten Commandments of Statistics
I. Get as large a sample as you can.
A. Large N provides for more stable measurement of variables, they are less likely to be affected by outliers.
B. Large N also provides for distributions that are more normal, or better reflect the full range of scores in the population.
II. Run as few statistical tests as you can.
A. running several tests increase the risk of a Type 1 error
B. focus your results as much as possible
III. Never Read more [...] 7 com
The Australian reports a major new controversy after Britain's Met Office denounced research from Stefan Rahmstorf suggesting that sea levels may increase by more than 1.8m by 2100.
Jason Lowe, a leading Met Office climate researcher, said: "We think such a big rise by 2100 is actually incredibly unlikely. The mathematical approach used to calculate the rise is completely unsatisfactory."
Critic Simon Holgate, a sea-level expert at the Proudman Oceanographic Laboratory, Merseyside, has written Read more [...] 24 com
Environment minister Peter Garratt claimed recent figures on Australian temperature prove Opposition leader Tony Abbott was wrong to claim that the world had stopped warming.
Substitute Australia for the World, and the last 100 years for 10 years, and you might get close to the actual claim, similar to that made by respected climate physicist Roy Spencer that "there has been no net warming in the last 11 years or so".
Itâ€™s easy -- but confused -- to find a limited region with a different Read more [...] 3 com
Our approach so far has been to model natural climate variation of global temperature with sinusoidal curves, and potential AGW as increasing trends. A new algorithm called EMD (Empirical Mode Decomposition) promises to more robustly identify cyclical natural variation (NV), showing the contribution of NV and AGW to global temperature, and testing the IPCC claim that most of the recent warming is due to AGW.
Underestimation of natural variation (NV) is a crucial flaw in the IPCC's logic, according Read more [...] 41 com
This numeracy exercise for schools can be adapted to grades pre-up. You need:
1. A number of strong magnets, at least two per group
2. Iron filings
3. Selection of nuts of various metals: iron, copper, brass, some lead sinkers.
The hour long exercise is presented as an introduction to scientific thinking in the higher grades. I don't worry about this for lower grades.
I usually choose an assistant to help handing out magnets, though this changes throughout.
1. Discovery - I introduce the magnets Read more [...] one
Here is the abstract for our comment submitted to Geophysical Research Letters today. Bob Tisdale is acknowledged as the source of the idea in the first paragraph. Lets see how it goes. If you would like a copy, contact me via the form above.
Update: Now available from arXiv
Comment on "Influence of the Southern Oscillation on tropospheric temperature" by J. D. McLean, C. R. de Freitas, and R. M. Carter
David R.B. Stockwell and Anthony Cox
We demonstrate an alternative correlation Read more [...] 35 com
A potential AGW buster, attributing decadal temperature variation largely to internal oceanic effects, ENSO and over the longer term the 1976 Great Pacific Climate Shift, as we did here, is a new paper by Australian John McLean, with New Zealander Chris de Freitas, and Australian ex-pat Kiwi Bob Carter.
That mean global tropospheric temperature has for the last 50 years fallen and risen in close accord with the SOI of 5â€“7 months earlier shows the potential of natural forcing mechanisms Read more [...] 110 com
The replication of the highly influential Rahmstorf 2007 A Semi-Empirical Approach to Sea Level Rise, one of the main sources of projected sea level rise, was reported in the previous post.
In a now discredited (and disowned) Rahmstorf et al 2007 publication, Steve McIntyre showed that Rahmstorf had pulled an elaborate stunt on the community by dressing up a simple triangular filter with "singular spectrum analysis" with "embedding dimensions", I can now report another, perhaps even more spectacular Read more [...] 6 com
Published in Science, this Rahmstorf 2007 article provides a high-end estimate of sea level rise of over a meter by the end of the century (rate of 10mm/yr). Linear extrapolation puts the rate of increase at only 1.4mm and 1.7mm per year depending on start date (1860 or 1950).
The paper was followed by two critical comments, both bashing the statistics, and these are attached to the link above. Rahmstorf replied to those comments. The issues raised are familiar to readers of this, CA, Lucia, Read more [...] 21 com