JoNova

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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Deadliest droughts in India were before 1924

Next time someone tells you how extreme the climate is today remind them that five million people died in a drought in 1896 in India. That was the same year a brutally hot summer in Australia caused 400 deaths and people fled the inland heat on emergency trains. Somewhere between 1 and 5 million people died a few years later in the next drought — the same time as Australia’s “Federation drought”.

Spot the effect of CO2 in 150 years of rainfall of India:

Average rainfall anomalies in India from 1850 – 2016 from IMD (black) and GISS (red).  | Click to read the official caption.

Famine deaths have largely been eliminated in India, mostly thanks to better transport and organisation, higher yields (thanks to fertilizer and CO2) and irrigation. Droughts still happen but in a population that has grown from 250 million in 1880 to a billion in 2000 the extraordinary thing is that more people starved of famine when the population was only a quarter of the size and CO2 levels were “perfecto”.

Weakened people died of cholera and malaria, and bubonic plague too.  Death rates to these diseases often doubled or tripled.

Famine, India, 1896.

Thanks to [...]

Blame Climate Change for stupid British Voters choosing Brexit says ABC

If only we had built more windmills, and changed more light-globes we could have prevented the British voting to control their own nation. It all makes sense — if you are insane, or a broadcaster paid one billion a year to promote Big Government.

What a disaster — the fifth largest economy choose to trade more with the rest of the world and be less under the thumb of Germany and Brussels. Such madness needs an explanification. So here it is: Our coal plants caused a terrible drought in Syria which made lots of nice people seek refuge in rich countries, I mean “globally”, and that made people talk about a refugee problem in the UK (which wasn’t really a problem, see) and that made scared, selfish and small minded populist voters choose fear and Brexit over the glorious wonder of the EU.

 This is the genius analysis we pay Sabra Lane and the ABC for:

SABRA LANE: Could it be that Brexit, the UK voting to leave the EU, is the result of a cascading series of events due in part to climate change?

ROBERT GLASSER: Yeah, so there was a persistent [...]

All that CO2 in the last 50 years and droughts are less common in Australia

No link between droughts and climate change in Australia

Ken Stewart finds that rainfall may have fallen in the last 30 years over Southern Australia but it has stayed remarkably constant in the long run.

Fig. 2: Cool season rainfall, Southern Australia, 1900-2017

Oops! Rainfall has in fact increased over southern Australia.

Stewart has also looked at the number of consecutive dry months across Australia. Looking at both 12 month periods and at 36 month periods it’s clear that we had more severe droughts more often from 1900-1970. The only exceptions are in SW WA (which is having a good year for rain this year) and small parts of Victoria and Tasmania.

Fig. 4:  Number of consecutive months per calendar year of 12 months severe rain deficiency: Australia

Don’t forget to pop in at Kens Kingdom and say thanks for all the work he does.

Ken Stewart is not paid but can create these graphs. The Australian BoM gets a million dollars a day, and Ken used their definition of a drought, but there are no press releases about this from the BoM.

The ABC gets $3 million dollars a day. If [...]

The rise of Climate superstition: Droughts, heatwaves, random noise is “proof” of anything you like

All around the world the climate druids are at work.

Show me the error bars

Once upon a time a scientist talked about thirty year trends and anachronistic things like “confidence intervals”. Now, thanks to the discovery of Unscience, any noisy, random short data is fair game to be declared undeniable climate change. Periods of flooding also qualify, as do periods of nice weather, though strangely no one mentions those. Where are the headlines? If climate change caused drought on the East Coast of Australia, it’s also causing average rain and good crops in Western Australia.

In terms of scientific data analysis we don’t get that many droughts or six-day-August-heatwaves to analyze. They’re complex phenomena caused by multiple factors and we only have short records. This makes them ideal to be oversold to hapless folk as a “sign” of climate change.

When we have data, we find global droughts haven’t changed much in the last 60 years. When we can scratch together longer proxies, we find that 1000 year rainfall studies show droughts and floods used to be longer and worse.  In Europe and the US megadroughts happened in the last 2,000 years. The droughts of 1315, or 1540, etc, [...]

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 [...]

Megadroughts in past 2000 years worse, longer, than current droughts

What hockeystick eh?

A new atlas shows droughts of the past were worse than those today — and they cannot have been caused by man-made CO2. Despite the claims of “unprecedented” droughts, the worst droughts in Europe and the US were a thousand years ago. Cook et al 2015[1] put together an old world drought atlas from tree rings data as a proxy for summer wetness and dryness across Europe. They compare the severity and timing of European droughts with the North American Drought Atlas (NADA) released in 2004. Yes, it’s a tree ring study with all the caveats about how trees are responding to several factors at once etc etc. But at least the modern era is measured with the same proxy as used in the old eras.

Something else is causing droughts, something modern models don’t include:

“megadroughts reconstructed over north-central Europe in the 11th and mid-15th centuries reinforce other evidence from North America and Asia that droughts were more severe, extensive, and prolonged over Northern Hemisphere land areas before the 20th century, with an inadequate understanding of their causes.”

The worst megadrought in the California and Nevada regions was from 832 to 1074 CE (golly, [...]

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. [...]

Nature paper: Global droughts unchanged in 60 years

How many images have we seen of drought-stricken cracked land, or been told this is the future? How many headlines have suggested that global warming causes droughts?

Since the end of World War II humans have produced some 85% of all their CO2 emissions, but here is a new study showing that for all those emissions, and for all that warming, droughts back then were just as bad globally as they are today.

Essentially, researchers thought that the Palmer Drought Severity Index (PDSI) was the way to measure global drought levels, and they thought that warming would increase global drought conditions. But the PDSI considers only temperature, not humidity, sunlight and wind. This paper shows that when these factors are included, worldwide drought is about the same now as it was in 1950.

Researchers are finally accounting for the fact that a warmer world usually means more evaporation (especially from the ocean) and thus more rain. It’s good to see that someone has crunched those complex numbers on a global scale. Credit to Sheffield, Wood & Roderick.

Figure 1 | Global average time series of the PDSI and area in drought. a, PDSI_Th (blue line) and PDSI_PM (red line). [...]

Droughts might not be due to carbon-dioxide, says CSIRO

Still in the theme of Shock!-The-Media-IS-Reporting-The-News: The Canberra Times announced on it’s front page that CSIRO is not so sure that droughts are due to increased carbon dioxide. Only a few months ago, they announced the exact opposite.

September 2009: A three-year collaboration between the Bureau of Meteorology and CSIRO has confirmed what many scientists long suspected: that the 13-year drought is not just a natural dry stretch but a shift related to climate change.

Jan 2010: One of the report’s co-authors, hydrologist David Post, told The Canberra Times there was ”no evidence” linking drought to climate change in eastern Australia, including the Murray-Darling Basin.

Back in September, this long study was based on the old trick of using climate models and “subtracting” the natural causes to see what’s left. It’s also known as “Argument from Ignorance”. Since we can’t predict the climate five years in advance, obviously there are factors or weightings in those climate models that aren’t right. Ruling out “what we know” doesn’t prove anything at all, except that there is a lot we don’t know.

When David Stockwell analysed climate models and Australian droughts, he found that random numbers were more likely to predict droughts successfully. [...]