A Change in Climate

Cold vs heat deaths

Global warming is such a multi-faceted topic and apparently will require such vast societal changes to mitigate its effects that to bring everyone along it requires trust, that is, trust that experts are rigorously adhering to scientific methods of data gathering and analysis.

Climate science has been plagued by alarmism; for decades warmists have been making predictions that don't pan out--for example, 2000's “snowfalls are just a thing of the past" and hockey-stick graphs that purport to show that temperature is rising at an accelerating rate.

Very few of us are climate scientists, but nearly all of us know something about human behavior. If a salesman is caught in a lie or a gross exaggeration, it causes us to distrust what is being sold though it may be a perfectly fine product. Trust won't be the result if climate change activists try to silence dissenters, or don't have better answers than "90% of climate experts believe what I believe."

Bjorn Lomborg ("Climate change is real, but it’s not the apocalyptic threat that we’ve been told it is") is worth listening to because he refuses to accept climate-change declarations that are unexamined. Most recently he took issue with the assertion that human activity is the main factor in the rise in heat deaths: [bold added]

The [Lancet] study offers a frightening statistic: Rapidly rising temperatures have increased annual global heat deaths among older people by 68% in less than two decades...

But while their model for heat deaths is based on solid academic research, the report commits an amateur statistical fallacy by blaming the increase in heat deaths on “rapidly increasing temperatures.”

Annual heat deaths have increased significantly among people 65 and older world-wide. The average deaths per year increased 68% from the early 2000s to the late 2010s. But that is almost entirely because there are so many more older people today than there were 20 years ago, in no small part thanks to medical innovations that keep us alive longer. Measured across the same time span the Lancet maps heat deaths, the number of people 65 and older has risen by 60%, or almost as much as heat deaths. When the increase in heat mortality is adjusted for this population growth, the actual rise that can be attributed to rising temperatures is only 5%.

Asserting that elderly heat deaths have risen by 68% without noting that the elderly population has increased by 60% is a serious omission. And we haven't even considered how warmer temperatures have reduced deaths in seniors:

In the U.S. and Canada between 2000 and 2019, an average of 20,000 people died from heat annually and more than 170,000 from cold. This omission matters even more because cold deaths are decreasing with rising temperatures. Modeling from the Global Burden of Disease replicates the relatively small increase in heat deaths shown by the Lancet, but shows a much larger decline in cold deaths from rising temperatures. Based on today’s population size, the current temperatures cause about 17,000 more heat deaths in older people, but also result in more than half a million fewer cold deaths. Reporting one finding without the other is misleading about the true effect of climate change.

Meanwhile global-warming experts and activists from all over the world are flying to Egypt to attend the United Nations climate change conference, COP27, which starts this week.