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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1000 year rainfall study suggests droughts and floods used to be longer, worse

A study done on… golly, Antarctic Ice, allegedly shows that in the catchment area for Newcastle in NSW, Australia, the last 100 years have been pretty darn nice, compared to the past when droughts and big-wet periods used to last a lot longer.

Set aside, for a moment, that the ice cores are thousands of kilometers away and in a totally different climate, if they are right, if, then natural climate change is much worse than our short climate records are telling us. And if our current records are so inadequate and don’t represent the “old-Normal”, then we have a flying pigs of predicting the “New Normal”. Has the climate changed at all, or is the new one just like the old old one?

Hydroclimatologist and lead author, Dr Carly Tozer from the ACE CRC said the research showed exposure to drought and flood risk was higher than previously estimated.

“The study showed that modern climate records, which are available for the past one hundred years at best, do not capture the full range of rainfall variability that has occurred,” Dr Tozer said.

“The wet and dry periods experienced since 1900 have been relatively [...]

Australia has had megadroughts for the last thousand years says ice core study

A new study of Law Dome Ice cores tells us that droughts are common in Australia, and that there appears to be eight mega-droughts over the last thousand years, including one that lasted a whopping 39 years from 1174- 1212AD. By their reckoning the 12th Century in Australia was a shocker with 80% of it spent in drought conditions. Things weren’t so bad from 1260 – 1860, at least, as far as they can tell. The researchers are convinced theirs is the first millennial-length Australian drought record. It does seem significant.

The researchers, sensibly, think we might want to pay attention to the Pacific cycles and store a bit more water. Without fanfare the paper also suggests that droughts were worse in medieval times.

“this work suggests Australia may also have experienced mega-droughts during the Medieval period that have no modern analog. Therefore, management of water infrastructure in eastern Australia needs to account for decadal-scale droughts being a normal feature of the hydrological cycle.”

h/t to Paul Homewood at Notalotofpeopleknowthat

The ABC reported this largely as a water management story, without asking whether their past stories that blamed CO2 for droughts were less likely to be true. [...]

Spinning more bad news to pretend it answers skeptics. When 400 “equals” zero

Believers really do have trouble with numbers. Today 400 is apparently a lot like zero.

Since when was 400 years a gap that anyone called “close”? Especially when we are talking about a molecular effect that works in microseconds (or hey, even less).

Newspapers today are full of the spin that an Antarctic survey by Pedro et al, that found CO2 only lagged temperature by a mere tiny 400 years ‘… “addressed the argument of “climate sceptics” that CO2 increases did not lead to temperature rises because the temperature rise must come first.’ [The Australian]. Didn’t the editor notice that a lag of 400 years is still a lag? Did the journalist (Rosanne Hunt) not realize that even if the lag was measured in hours it still means temperature drives carbon dioxide, and not the other way around? This is nonsense on stilts. The Australian only published 6 lines, and one of them is barking.

The “lag” might be small on this scale, but it’s long compared to a taxpayers lifespan. Graph from the Australian Antarctic Division


The Australian Government (Antarctic Division) says it “closes the gap” and “Their findings suggest that feedbacks in the climate system – in [...]

Ice Core evidence — where is carbon’s “major effect”?

The ice cores are often lauded as evidence of the effects of carbon dioxide. Frank Lansner asks a pointed question and goes hunting to find any effects that can be attributed to carbon.

Where is the data that actually shows a strong and important warming effect of CO2? If CO2 has this strong warming effect, would not nature reflect this in data?

He has collected together the data from the last four warm spells (the nice interglacials between all the long ice ages) into one average “peak”. The common pattern of the rise and fall has already been recorded in many scientific papers. Orbital changes trigger the temperatures to rise first and about 800 years later (thanks to the oceans releasing CO2), carbon dioxide levels begin to climb. At the end of a patch of several thousand warm years, temperatures begin to fall, and thousands of years later the carbon dioxide levels slowly decline. No one is really contesting this order of things any more. What is contested is that those who feel carbon is a major driver estimate that the carbon dioxide unleashed by the warming then causes major amplification or [...]

The big picture: 65 million years of temperature swings

Greenland Interglacial Temperatures – last 10,000 years. Are we headed for an ice age? (See below for more detail.)

David Lappi is a geologist from Alaska who has sent in a set of beautiful graphs–including an especially prosaic one of the last 10,000 years in Greenland–that he put together himself (and which I’ve copied here at the top).

If you wonder where today’s temperature fits in with the grand scheme of time on Earth since the dinosaurs were wiped out, here’s the history. We start with the whole 65 million years, then zoom in, and zoom in again to the last 12,000 from both ends of the world. What’s obvious is that in terms of homo sapiens history, things are warm now (because we’re not in an ice age). But, in terms of homo sapiens civilization, things are cooler than usual, and appear to be cooling.

Then again, since T-rex & Co. vanished, it’s been one long slide down the thermometer, and our current “record heatwave” is far cooler than normal. The dinosaurs would have scoffed at us: “What? You think this is warm?”

With so much volatility in the graphs, anyone could play “pick a trend” and depending [...]

Science communication pollution

Here’s an example of SciComm Pollution — an article that leaves the world slightly less enlightened than they would have been had it not existed. It’s also proof that the media blackout works so well that even theoretically educated people like, say, an archaeologist, are unaware of basic uncontroversial scientific truths.  Here’s Michael Berry, in the Salt Lake Tribune, having trouble reasoning, missing the point, being fully a decade out of date, and acting unwittingly as a public relations agent for a giant  bureaucracy.

He tries to claim Senator Orrin Hatch and The Skeptics Handbook are wrong on the Vostok ice cores.