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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Death, disease, coming in 2050 says model of model

“Half a million deaths by 2050!”

The Lancet study in a nutshell:  Take climate models that don’t work, and guesstimate what might happen to agriculture because of the climate we probably won’t get. Then use those guesses of food production in 2050 to fantasize what that means for human mortality. After all, we don’t know how many people are killed today by “4% less fruit and vege and 0.7% less meat”, but we can estimate what that dietary change will do in 2050 after a medical revolution, 35 years of plant breeding and agricultural changes. Not to mention a few more rounds of global food fads and phases of Vegan, Paleo, Atkins, and 5:2 Fasting.  (But how did they factor in the mortality effect from another 2,000 episodes of MasterChef?)

Seriously, CO2 has increased crop yields, and will continue to do so until we hit 1000ppm (or maybe 2000). Around the planet, plants grow in warm places, and shrivel up and die in cold ones. So do people. Cold kills 20 times as many people as heat does. It must take a lot of modeling to calculate “more deaths” from two good outcomes.

Look at where fruit grows. In a warmer world, the [...]

Study on 74 million deaths: Cold weather kills 20 times more than heat does.

Of seventy four million deaths (that is quite some study) 7.7% of all deaths could be blamed on “non-optimal” temperatures according to Gasparrini et al in the Lancet. But look closely, and 7.3% of deaths were due to the cold and only 0.4% were due to the heat.

This may be part of the reason people retire to Florida, and not so much to Barrow, Alaska.

The biggest killers were not the heat waves that score the headlines, but the moderate cold. Winter kills. (Time to ban winter?)

Cold weather kills far more people than hot weather

Cold weather kills 20 times as many people as hot weather, according to an international study analyzing over 74 million deaths in 384 locations across 13 countries. The findings, published in The Lancet, also reveal that deaths due to moderately hot or cold weather substantially exceed those resulting from extreme heat waves or cold spells.

“It’s often assumed that extreme weather causes the majority of deaths, with most previous research focusing on the effects of extreme heat waves,” says lead author Dr Antonio Gasparrini from the London School of Hygiene & Tropical Medicine in the UK. “Our findings, from [...]

Global warming saves lives in Stockholm — but bad assumptions feed scary headlines

Here’s a tale of how to generate headlines from circular reasoning built on brave assumptions. All it requires are some unskeptical science journal editors and gullible journalists. Et Voila!

Congratulations to Chip Knappenberger, Pat Michaels, and Anthony Watts, whose response to Åström et al was published Wednesday.

In October 2013 Åström et al claimed that global warming had killed lots of people in Stockholm, hundreds. But the first thing you need to know is that they don’t appear to start with actual mortality data in the early 1900′s. Surprised? Me too. Anthony Watts found it hard to believe . The other thing worth knowing is that extreme heat was defined as the top 2% of hot days, and in Stockholm that mean everything above a terrifying 2-day-moving-average mean temperature of 19.6C (67 F).

From the methods:

We collected daily mortality during the period 1980-2009 and daily temperature data for the period 1900-2009 for Stockholm County, Sweden.

Åström 2013:  Figure 2 j Temperature distribution of 2-day moving average of mean temperatures during summer months. Grey distribution, 1900–1929; black distribution, 1980–2009.

It appears the authors compared calculated death rates (using a model) from 1900-1929 with rates from 1980-2009 and concluded that [...]

7,000 excess winter deaths in Australia and 1,500 in New Zealand each year

Excess winter deaths are more than triple the number killed on the road.

Indur Goklany compares average daily deaths for each month in Australia and New Zealand and shows that in both countries (like in much of the rest of the world) there are more deaths in the cooler months.

While climate change legislation aims to make the world cooler, statistics show that the cooler months consistently have higher mortality.

In the unlikely event that legislation might succeed in reducing global temperatures, based on past statistical records, thousands of extra people may die as a result. In study after study, it’s clear that more people die in the colder months than in the rest of the year. The trend applies even in warm countries like Australia.


Average daily deaths for each month in Australia (left axis, black numbers) and New Zealand (right axis, grey numbers) over a ten year period.


The statistics indicate that:

For the 10-year period, 1998-2007, Australia had excess winter deaths of 6,779 per yr out of a total of 131,613 deaths per yr (avg.) This works out to 5.2% of all deaths per yr (on avg). For the 10-yr period, 1999-2008, NZ [...]

Cold times means more death, war, rebellion, drought and flood in China

Tomb of Hong Quan Fu. Photo Iflwlou拍攝

It seems a warmer climate might be bad, but a colder one is deadly.

Once upon a time, people thought that overpopulation triggered crashes, but in this study by Lee and Zhang the hard numbers suggest instead that it was climate, and of course, it’s not the warmer kind of climate that causes the problems but the colder kind.

Malthusian cycles of population boom and bust aren’t the drivers here (though presumably having a large population means there is little buffer when the deadly cold spells hit).

From NIPCC:  Cold Periods caused population crashes in China over the last millenium

…there were 5 major population contractions in China between 1000 CE and 1911, and all of them occurred in periods with a cold climate, when mortality crises triggered population collapses. [Abstract]

How much fun can you have in a long frost? Almost every kind of uprising, pain or plague.

In one population crash, the losses were as high as 49% of the peak. In the face of a 50:50 death rate, “perspective” doesn’t seem like quite the right word.