An Earth scientist’s recent
article making the rounds on social media highlights a terrifying
conversation he had with “a very senior member” of the IPCC, which is the
UN’s body devoted to studying climate science. The upshot of their
conversation was that millions of people will die from climate change, a
conclusion that leads the author to lament that humans have created a
consumption-driven civilization that is “hell bent on destroying itself.”
As with most such alarmist rhetoric, there is little to document these
sweeping claims—even if we restrict ourselves to “official” sources of
information, including the IPCC reports themselves. The historical record
does not justify panic, but instead should lead us to
expect continued progress for humanity, so long as the normal operation of
voluntary market interactions continues without significant political
interference to sabotage it.
The Conversation
Here is the opening hook from James Dyke’s article, in which he grabs the
reader with an apocalyptic conversation:
It was the spring of 2011, and I had managed to corner a very senior
member of the Intergovernmental Panel on Climate Change (IPCC)
during a coffee break at a workshop…
The IPCC reviews the vast amounts of science being generated around
climate change and produces assessment reports every four years.
Given the impact the IPPC’s findings can have on policy and industry, great
care is made to carefully present and communicate its scientific findings. So
I wasn’t expecting much when I straight out asked him how much warming he
thought we were going to achieve before we manage to make the required cuts
to greenhouse gas emissions.
“Oh, I think we’re heading towards 3°C at least,” he said.
…
“But what about the many millions of people directly threatened,” I
went on. “Those living in low-lying nations, the farmers affected by abrupt
changes in weather, kids exposed to new diseases?”
He gave a sigh, paused for a few seconds, and a sad, resigned smile
crept over his face. He then simply said: “They will die.”
Putting aside the creepiness of someone smiling as he predicts millions of
deaths—sort of like a
James Bond villain—we must inquire: How plausible are these warnings?
Does the climate change literature actually support such bold projections?
As it turns out, the answer is “no.” It is certainly true that there are
many particular dangers regarding climate change, which could have
deleterious consequences on human welfare (broadly defined). But in order to
conclude that millions—or even billions, as the author of the
article states in his concluding remarks—of deaths hang in the balance, we
have to grossly exaggerate all of the various mechanisms and scenarios, and we
have to assume that humans do nothing to adapt to the changing circumstances
over the course of decades.
In reality, it is much more likely that humans will adapt to whatever
changes the climate brings them in the coming decades, and that various
measures of human well-being—including not just GDP but also life expectancy
and declining mortality rates from various ailments—will continue to improve.
The voluntary market economy is an excellent general purpose solution to the
challenges facing humanity, including the handling of whatever curve balls
climate change might throw.
IPCC’s Summary of Climate Change Damages
Unfortunately, it is difficult to come up with a statistic such as, “How
many excess deaths does the IPCC predict from climate change by the year
2100, if governments don’t take further action?” If you consult the AR5,
which is the latest IPCC report, and look at chapter
11 (Working Group II) on the impacts of climate change on human
health, you will see various trouble areas and figures concerning at-risk
populations, but nothing so crisp as to allow us to evaluate the casual
claims of millions of deaths.
However, the IPCC chapter does tell us upfront:
The Fourth Assessment Report (AR4) pointed to dramatic
improvement in life expectancy in most parts of the world in the 20th
century, and this trend has continued through the first decade of the 21st
century (Wang et al., 2012). Rapid progress in a few
countries (especially China) has dominated global averages, but most
countries have benefited from substantial reductions in mortality.
There remain sizable and avoidable inequalities in life expectancy within and
between nations in terms of education, income, and ethnicity (Beaglehole and
Bonita, 2008) and in some countries, official statistics are so patchy in
quality and coverage that it is difficult to draw firm conclusions about
health trends (Byass, 2010). Years lived with disability have tended to increase
in most countries (Salomon et al., 2012). If economic
development continues as forecast, it is expected that mortality rates will
continue to fall in most countries; the World Health Organization (WHO)
estimates the global burden of disease (measured in disability-adjusted life
years per capita) will decrease by 30% by 2030, compared with 2004 (WHO,
2008a). The underlying causes of global poor health are expected to change
substantially, with much greater prominence of chronic diseases and injury;
nevertheless, the major infectious diseases of adults and children will
remain important in some regions, particularly sub-Saharan Africa and South
Asia (Hughes et al., 2011). [IPCC Fifth Assessment Report, Working Group
II, Chapter
11, bold added.]
Later in that same chapter, we see the following table, which is
illustrative of the general pattern when it comes to long-term projections
about climate change harms to humanity:
As the table indicates, the absolute number (let alone
the percentage of the population) of undernourished children in all
developing countries, even with climate change, is projected
(with certain assumptions) to drop by 9.4 million from the year 2000 to 2050.
It’s true that the number increases in sub-Saharan African, but it falls in
every other region. (It also rises in sub-Saharan Africa even without climate
change.) We should also keep in mind that UN
projections assume the populations in 26 African countries will at
least double by 2050, meaning that the percentage of
children who are malnourished still drops even in sub-Saharan Africa and even
with climate change, according to the UN’s estimates.
As I have explained — most recently in this
article — when it comes to climate change, the big projected damages
don’t occur until many decades into the future. But for those people,
standard economic growth will have raised their baseline standard of living by
so much, that even if the UN-endorsed best-guess projections of climate
change are accurate, those humans will still be much better off than we are
today.
“It’s Getting So Much Better All the Time”
To see more evidence of this pattern, consider the following chart depicting
mortality from various causes, created by Our World in Data using data from
the Institute for Health Metrics and Evaluation (IHME), 2018:
As the chart indicates, the death rates from various types of causes have
fallen sharply around the world, particularly those from communicable
diseases, and all within the last 20 years—when climate change was ostensibly
becoming a deadly problem for humanity that only “deniers” could ignore.
For another line of evidence, let me show you a table where the UN did give
us some measures of “aggregate” damages from climate change. Specifically, in
chapter 10 of the AR5 we see the following table summarizing the climate
change economics literature on the subject:
Source: Table 10.B.1, IPCC AR5, Working Group II, p. 82.
As the table summarizes, even for warming of 3 degrees Celsius, all but
one of the studies predicted non-alarming amounts of damage. (I discuss the
table more in this
article.) Now I should emphasize that although the impacts are measured in
GDP terms, these damage estimates include things like impacts on human health
and mortality. It isn’t simply a measured reduction in the flow of TV output
because some of the factories are under the sea.
In any event, it should be clear from the table that—contrary to James
Dyke—we should not expect millions, let alone billions (!), of people to die
from climate change. Even if climate change proceeds as the peer-reviewed
literature assumes in the most pessimistic emissions scenarios, it will
probably merely mean that people in the year 2100 will only be a lot richer
than we are, as opposed to a whole lot richer.
What about the Catastrophic Scenarios?
Now it’s true, nobody can guarantee that there won’t be
a climate change catastrophe. But we must realize that at least several of
the featured studies warning of huge negative impacts are based on obviously
flawed assumptions.
Oren Cass provides us with some
examples. One study looked at the increase in mortality in a cold,
northern US city during a particularly brutal summer, and then extrapolated
to show a staggering number of excess heat deaths decades down the road, when
such “bad summers” were more common. Yet in the projections, the northern
cities were no hotter than southern US cities are right now,
and yes these southern cities don’t have nearly the same heat death rate as
is projected for the northern cities decades down the road.
What is happening here should be obvious after a moment’s reflection: A
northern city like Philadelphia is not adapted to hot summer the way Houston
or Las Vegas is. But if climate change did indeed make such temperatures the
norm—over the course of several decades—then the residents of the
northern cities would adapt. They would install more air conditioning, and
the people born in the year (say) 2080 would be much better able physically
to cope with higher temperatures in 2100 than the people alive today.
This is also the general response I would give the issue of sea level
rise. I think that much of the rhetoric here is overblown, but even to the
extent that it is true, we don’t need to worry about
millions of people literally dying. Even if true, this is a problem that will
manifest itself over several generations. If certain coastal
regions are truly threatened, then in the worst case humans will stop
building (and eventually even repairing) the houses and businesses near the
rising seas. Humans can gradually move out of these (sinking) neighborhoods
and go further inland, through a process of attrition rather than mass
migration in the face of a tidal wave.
Conclusion
The climate change alarmists are given a free pass to throw out the most
absurd rhetoric, such as a recent author’s warning that potentially billions of
people could die because of human-caused climate change. Yet despite their
claimed fidelity to the “consensus science,” such claims are not supported by
the UN’s own climate change reports.
The most alarming of the projections of climate change damages rely on
naïve assumptions about human adaptability. Even if we stipulate the basic
projections made in the most recent IPCC assessment, what “unchecked” climate
change will probably mean is that our great-grandkids will see a smaller
increase in their standard of living than they otherwise would have, if some
of the carbon dioxide in the atmosphere could have been costlessly removed.
Such a possible outcome is no reason to panic, and it doesn’t justify massive
government intervention in the energy or transportation sectors.
