The UnAustralian

Saturday, March 15, 2003
 
A New Low in Climate Pseudoscience: Part 3

On the significance of the MWP and little Ice Age, Daly states:

This account of climatic history contains two serious difficulties for the present global warming theory.

1) If the Medieval Warm Period was warmer than today, with no greenhouse gas contribution, what would be so unusual about modern times being warm also?

2) If the variable sun caused both the Medieval Warm Period and the Little Ice Age, would not the stronger solar activity of the 20th century account for most, if not all, of the claimed 20th century warmth?

Both propositions posed a serious threat to continued public acceptance of the climate modeller's catastrophic view of future climate. This is because new findings in solar science suggested that the sun, not greenhouse gases, were the primary driver of 20th century climate trends.

In order to accept this, one must have a pretty skewed view of reality. In modern day climatic science, there are three main variables which effect global tempertures in the century timescale; greenhouse gases, volcano, and solar variability. None of these variables can explain the climate on their own, you need all three. Or as Mann and co-workers say "While the natural (solar and volcanic) forcings appear to be important factors governing the natural variations of temperatures in past centuries, only human greenhouse gas forcing alone ... can statistically explain the unusual warmth of the past few decades".

If one accepts that temperture changes are caused by the sun, greenhouse gases and volcanos, then the existance of a solar induced warm and then cold period in the earths past shouldn't prove to be a problem.
| 6:03 PM
 
A New Low in Climate Pseudoscience: Part 2

The next part of this series summarises why Daly is wrong. It goes kind of like this:

* Daly misrepresents the IPCC, in particular he blows up the significance of the MWP and little ice age.
* Daly misrepresents the Mann paper, and uses these misrepresentations to build his case.
* Daly complainants about tree rings are overblown.
* Daly cherry picks his regional studies, and overstates their significance.

| 5:38 PM
 
A New Low in Climate Pseudoscience: Part 1

At the request of Ken Parish, I've looked into a long article by global warming skeptic John Daly titled "The `Hockey Stick': A New Low in Climate Science".

I'll start by summarising Daly's piece. Sadly, it isn't easy to summarise, given the large amount of vitriol and insults which are scattered throughout the work, but I'll do my best. Daly starts by reproducing a figure from the IPCC 1995 report showing temperature change over the last 1000 years. In particular, there is a medieval warm period (700 - 1300 AD), and a little ice age (1560 - 1830 AD). He then gives some more details about the warming and cooling, and speculates that the temperatures changes are solar induced. He believes (incorrectly) that this facts pose a major problem for climatic scientists, and makes two statements:

1) If the Medieval Warm Period was warmer than today, with no greenhouse gas contribution, what would be so unusual about modern times being warm also?

2) If the variable sun caused both the Medieval Warm Period and the Little Ice Age, would not the stronger solar activity of the 20th century account for most, if not all, of the claimed 20th century warmth?

However, now he presents a paper by Dr Michael Mann and co-workers (Mann, 1999) stating "...in one scientific coup overturned the whole of climate history" (ignoring that the same authors had used exactly the same technique in a paper published the year before (Mann, 1998)). As Daly states "Using tree rings as a basis for assessing past temperature changes back to the year 1,000 AD, supplemented by other proxies from more recent centuries, Mann completely redrew the history, turning the Medieval Warm Period and Little Ice Age into non-events, consigned to a kind of Orwellian `memory hole'".

Daly now starts to critique the paper, initially stating "At that point, Mann completed the coup and crudely grafted the surface temperature record of the 20th century (shown in red and itself largely the product of urban heat islands) onto the pre-1900 tree ring record. The effect was visually dramatic as the 20th century was portrayed as a climate rocketing out of control. The red line extends all the way to 1998 (Mann's `warmest year of the millennium'), a year warmed by the big El Niño of that year".

He pretends that the Mann paper was a bloodless coup in the climate sciences and was rapidly accepted by the mainstream science (and fully accepted by the time the IPCC wrote their 2001 report).

Daly now presents a number of reasons as too why tree-rings are poor climate indicators, and then states "[t]o disprove the `Hockey Stick', it is sufficient to merely demonstrate conclusively the existence of the Medieval Warm Period and/or the Little Ice Age in proxy and/or historical evidence from around the world".

Next Daly presents 14 exhibits (regional studies) which indicate the existence of a medieval warm period, and small ice age.

The next section (titled "The Science that Lost its Way") doesn't concern the scientific techniques and interpretations used, so I'll ignore it.

| 4:20 PM
Wednesday, March 12, 2003
 
Insane in the Brain

Calpundit writes about Steven Den Beste:

Steven Den Beste continues his long, lonely journey to complete lunacy. Today he's worried about continuing French opposition to our war and asks:

"Do they see the stakes as being high enough so that they might actually threaten to nuke us?"

It's hardly even funny to mock him any more. He really needs to seek professional help.

Maybe I've been reading to many neocon sites, but I'm skeptical that Den Beste's journey can be described as "lonely".
| 1:04 PM
Tuesday, March 11, 2003
 
Gulf War I

Guess who, in 1992, wrote: "The Gulf War was a limited-objective war. If it had not been, we would be ruling Baghdad today - at unpardonable expense in terms of money, lives lost and ruined regional relationships."

That's right, Colin Powell.
| 10:17 PM
 
New Zealand and the Economy

There is an interesting article by Alan Wood in todays Australian.

As somebody who lived through NZs reforms in the 1980s, I'm extremely skeptical of economic rationalists.
| 9:59 PM
 
Medieval Warm Period

One theme in global warming skeptics litany is the medieval warm period. This is commonly presented as evidence that the earth's climate can change without human influence (something which isn't debated by scientists, rather this is a strawman put forward by the skeptics). However one common meme within this theme is that the temperatures were higher than modern temperatures. For example;

[B]etween 900 and 1100 the climate dramatically warmed. Known as the Medieval Warm Period, the temperature rose by more than 1° F to an average of 60° or 61° F, as much as 2° F warmer than today. Again, the temperature during this period is similar to Greenhouse predictions for 2100, a prospect global warming theory proponents insist should be viewed with alarm. But judging by how Europe prospered during this era, there is little to be alarmed about. The warming that occurred between 1000 and 1350 caused the ice in the North Atlantic to retreat and permitted Norsemen to colonize Iceland and Greenland. Back then, Greenland was actually green. Europe emerged from the Dark Ages in a period that was characterized by bountiful harvests and great economic prosperity. So mild was the climate that wine grapes were grown in England and Nova Scotia. (Link)

Or as Australia's own, Aaron Oakley writes:

During the medieval optimum the world was warmer than it is today (I understand that they were even growing wine grapes in England). Europe was healthier than it was during the subsequent little ice age. (Can be found by going here then clicking the comments link).

These English grapes strike me as a pretty weak piece of evidence for higher temperatures, given that England has plenty of vineyards today.

Likewise, Greenland is still green (remember that Eric the Red wouldn't have be describing the interior or arial photos of Greenland, but rather potential colonisation sites).

So how does science see the medieval warm period? This section is from the the IPCC's 2001 report into the scientific basis for global warming:

As with the "Little Ice Age", the posited "Medieval Warm Period" appears to have been less distinct, more moderate in amplitude, and somewhat different in timing at the hemispheric scale than is typically inferred for the conventionally-defined European epoch. The Northern Hemisphere mean temperature estimates of Jones et al. (1998), Mann et al. (1999), and Crowley and Lowery (2000) show temperatures from the 11th to 14th centuries to be about 0.2°C warmer than those from the 15th to 19th centuries, but rather below mid-20th century temperatures. The long-term hemispheric trend is best described as a modest and irregular cooling from AD 1000 to around 1850 to 1900, followed by an abrupt 20th century warming. Regional evidence is, however, quite variable. Crowley and Lowery (2000) show that western Greenland exhibited anomalous warmth locally only around AD 1000 (and to a lesser extent, around AD 1400), with quite cold conditions during the latter part of the 11th century, while Scandinavian summer temperatures appeared relatively warm only during the 11th and early 12th centuries. Crowley and Lowery (2000) find no evidence for warmth in the tropics. Regional evidence for medieval warmth elsewhere in the Northern Hemisphere is so variable that eastern, yet not western, China appears to have been warm by 20th century standards from the 9th to 13th centuries. The 12th and 14th centuries appear to have been mainly cold in China (Wang et al., 1998a,b; Wang and Gong, 2000). The restricted evidence from the Southern Hemisphere, e.g., the Tasmanian tree-ring temperature reconstruction of Cook et al. (1999), shows no evidence for a distinct Medieval Warm Period. (Link)

A graph showing tree ring derived temperatures can be found here.

A more recent paper (Jan Esper, Edward R. Cook and Fritz H. Schweingruber, Science 2002, 295, 2250 - 2253) claims that the temperatures reconstructions cited above underestimate the magnitude of the warming. It suggests that the MWP was (at it's peak) about as hot as 1990 (ie. significantly cooler than today).

Update: The Greenland link doesn't work (that will teach me to deep link). To see the picture, go here and click on the picture of the ruins of the Hvalsey Church (this was one of the Church's in the Vikings Eastern Settlement. The important thing to note is the colour of the background.

| 8:14 PM
Sunday, March 09, 2003
 
Lies, damm lies, and John Howard

I hope that this isn't true, but going by the character of the Australian PM, it really wouldn't surprise me.
| 5:09 PM
 
How I Could Support the War

It shouldn't be any surprise to anyone that I don't support a war in Iraq. However, I've been doing some thinking on what would make me change my opposition to an invasion of Iraq.

Basically, I think that a incredibly strong case can be made for an invasion on humanitarian grounds (most of the other reasons given strike me as a bunch of BS), however I don't trust Bush and co. to do a good job in the reconstruction. This is more important as it sounds, as a badly done post-war Iraq could well be worse than Saddam's Iraq. Another fear is the US economy, if the deficits start to mount, how willing will the administration be to pour money into Iraq.

So with this in mind, I've thought up a few scenarios which would help change my opposition to a war on Iraq.

* The US starts to do a decent job in reconstructing Afghanistan as a modern state (not a central government which controls a few cities, well the provinces are ruled by warlords).

* A very different US President than Bush is sitting in the Whitehouse.

* A significantly detailed plan for post war Iraq is released, with funding commitments.


| 5:04 PM
 
Dinosaurs Dead

No Bush cabinet hasn't been wiped out, but rather the asteroid strike that took out the dinosaurs may have been found. It's discussed here, with a cool picture here.
| 4:52 PM