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: yt=a+b.gt+ε An autoregressive model of changes in Read more [...] 119 com
If you have seen the articles on the NZ temperature adjustments and Nordic temperature adjustments you might be interested in the Australian data. The issue with NZ and Nordic data that the raw temperature data for weather stations do not show the temperature increases indicated by the IPCC, raising the question of how the data have been adjusted. As Prof. Karlen states in the ClimateGate email #1221683947, temperature at many stations has not exceeded early 20th century temperatures: .. data Read more [...] 19 com
Code and figures to quantify the answer to the question "Is ocean heat content is accelerating?" are below. The idea is that 'acceleration' is synonymous with the significance of a quadratic term in a regression: 1. Annual OHC data from NODC. 2. Fit a regression model (M1) incorporating linear and periodic terms of period 60 years (to account for Pacific Decadal Oscillation): x=time(OHC); f=x*pi*2/60; M1 = lm(OHC~x+sin(f)+cos(f)) 3. Fit another regression model with the addition of a quadratic Read more [...] 81 com
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 Abstract We demonstrate an alternative correlation Read more [...] 35 com
Last week I prepared a comment defending McLean's SOI paper. I shall send it in shortly. Basically, I extend their analysis a little and show that the majority of variation in a linear regression model predicting global temperature (not differences) can be accounted for using SOI-related terms. The sorry-state of Dr. Hathaway's prediction record is in the news. For example, in 2006, Dr. Hathaway looked at disturbances in the Earth's magnetic field that are caused by the Sun, and they were strong. Read more [...] 16 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 5–7 months earlier shows the potential of natural forcing mechanisms Read more [...] 110 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
Download: Structural break models of climatic regime-shifts: claims and forecasts Anthony asked if it would be difficult to statistically justify the breaks in temperature between 1976 and 1979 proposed by Quirk (2009) for Australian temperature. He has an interest in oceanographic regime-shifts and climate change. Sure, I said, a simple Chow test. We ended up rebutting the Easterling & Wehner (2009) claim that describing temperatures since 1998 as declining is 'cherry picking', finding a Read more [...] 49 com
Appearing in Energy and Environment (ee-20-4_7-stockwell2) is a note by myself on a paper by IPCC lead authors Rahmstorf, S., Cazenave A., Church J.A., Hansen J.E., Keeling R.F., Parker D.E., and R.C.J. Somerville, Recent climate observations compared to projections published in Science in 2007. As shown by 102 citations in Google Scholar already, Rahmstorf et al 2007 has been one of the main references for alarmist calls to action because the "climate system is responding more quickly than the Read more [...] 36 com
Given the way the components of the surface temperature record extracted from the SSA (singular spectrum analysis) line up with various potential causes of climate change in the previous post here, the temptation is to latch onto series 2, and say, aha, there is the forcing due to increase in CO2. It's the right shape, exponential. Its the right size, about 0.6C. But looking into fractal data is like seeing pictures in clouds. Be suspicious of magic methods that pull explanations out of the air. Read more [...] 26 com
The code for plotting the non-linear temperature trend, using SSA (singular spectrum analysis) in the figure below is here - ssa-demo. I have made it as turnkey as I can. The steps are: 1. Get and Install package ssa (http://r-forge.r-project.org/projects/ssa/). I had to hand-compile and move the C shared library around so it would find it, not sure why. 2. Run the script below with source("filename"). Uncomment line indicated after the first time to speed it up. You should get the following Read more [...] one
My signed copy of Heaven+Earth: Global Warming, the missing science by Australia's most eminent geologist arrived last week. Peter Gallagher has just reviewed it here, and I agree with most of his impressions. Apart from anything else it seems like a useful compendium of "History, Sun, Earth, Water, Air" facts and references, with over 500 pages and 2311 references. My hardcover version is laid out in a small book format with over-narrow margins, making it look a little like a "Backpackers Guide". Read more [...] 68 com
The Australian Bureau of Meteorology (BOM) has acquired daily weather data from many sites for many years and compiled it into a base that compares well with that from other countries. The data in various stages of treatment is available from Dr Stockwell through this site. It includes a small amount of infilling of missing data, usually by inserting the value(s) of an adjacent day. The infilling is not considered to alter the conclusions, but it is a mathematical convenience. It can be said of Read more [...] 30 com
Admin: Posted up for Steve, with an initial response by Miklos. The slides Steve referred to are here. My bad for not telling Miklos that. Link to TF&K08 Miskolczi theory proposes a tau (Ta if you will) significantly different from that found by at least a dozen other studies published in the peer-reviewed literature over more than a decade, as well as a number of other new relations A_A = E_D, f = 2/3 etc., etc. In the scientific processes I have been involved myself a number of times, Read more [...] 662 com
A feel-good story of nature's resiliency, "Doom and Boom on a Resilient Reef: Climate Change, Algal Overgrowth and Coral Recovery" has been making press with headlines focusing on the state of mind of the authors: Marine scientists say they are astonished at the spectacular recovery of certain coral reefs in Australia's Great Barrier Reef Marine Park from a devastating coral bleaching event in 2006. The paper is similarly emotive in parts, with words like "surprisingly" and "unexpectedly" describing Read more [...] one
Here is a summary of the chapters in my upcoming book Niche Modeling to be published by CRC Press. Many of the topics have been introduced as posts on the blog. My deepest thanks to everyone who has commented and so helped in the refinement of ideas, and particularly in providing motivation and focus. Writing a book is a huge task, much of it a slog, and its not over yet. But I hope to get it to the publishers so it will be available at the end of this year. Here is the dustjacket blurb: Through Read more [...] 4 com