The issue of climate change (or “global warming” as it used to be called) arouses much passion and public interest. There are three distinct issues subject to debate:
- Is there a decades-long trend towards higher temperatures worldwide?
- To what extent is such a trend, if it exists, caused by human activity, e.g. greenhouse (largely carbon) emissions?
- If there is a trend towards higher temperatures, what, if anything, should government do about it?
The preponderance of credible opinion is that “yes, there is a trend towards higher temperatures, although its precise slope and variability is subject to a range of estimates.” The above graphic of the 70-year decline in the mass of glaciers scattered around the world illustrates one of the arguments behind that opinion.
The answers to the second question are much less uniform. We know that the earth’s temperature has frequently varied by sizable amounts for millions of years. Variation in the sun’s radiation, the tilt of the earth’s poles and volcanic activity are cited as historical culprits. The precise contribution of these factors (“natural variability”) to the observed recent warming is unclear, but we know that human (“anthropogenic”) activity, such as the burning of coal, does release “greenhouse” gases that can contribute to higher temperatures.
Human activity. The answer to the “human activity” question is important because projections of future temperatures shape government policy and impact individuals’ behavior. But given the complexity of human activity, the magnitude of a likely increase is impossible to model with a high level of certainty, even with assuming no significant natural variability.
Consider, for example, that at the beginning of 2015 the International Maritime Organization decreed that ocean-going ships may not use fuel oil with more than 0.10% sulphur content, compared to the 3.50% limit in effect formerly. Atmospheric sulphur dioxide is well known to reduce global temperatures, as it does with major volcanic eruptions. Thus, this regulation is having the unintended consequence of promoting global warming, as detailed in technical studies.
Cool it! So, what, if anything, should governments do about an increase (precise magnitude unknown) in climate temperatures? It is clear that any increase will have a variety of negative and positive impacts, so perhaps the first step should be to “cool it” – to stop publishing one-sided alarmist tracts as “scientific studies” as the Obama administration has just done with its “The Impacts of Climate Change on Human Health in the United States.”
This document seeks to frighten its readers with such pronouncements as:
. . . climate change impacts endanger our health by affecting our food and water sources, the air we breathe, the weather we experience, and our interactions with the built and natural environments.
But as Bjorn Lomborg, the respected Danish environmentalist who believes that climate change is a genuine problem has noted, “the report reads like a sledgehammer that hypes the bad and skips over the good.” He is particularly scornful of its failure to point out the well-documented fact that more people die from cold weather than from hot – so that moderate global warming will result in fewer deaths directly on account of weather. The fact that retirees are more likely to move to warmer regions from cooler ones than the reverse is a common sense indicator.
The fact that agricultural and livestock production will be stimulated at higher latitudes (wheat in Greenland?) is glossed over casually in the report with the observation “in the near term, some high-latitude production export regions may benefit from changes in climate.”
More importantly, there is no discussion in the report of the incentives for people, businesses and communities to adapt to warmer weather, such as changes in building design and location, which don’t need any government incentives to come about.
What to do? Two modest suggestions. With sea levels likely to rise somewhat as those glaciers melt, a simple policy change by the U.S. government could reduce substantially property losses incurred by hurricanes and flooding. Far fewer structures would be built on easily flooded sites if the government’s Flood Insurance Program charged actuarially sound premiums which would discourage such building activity. The Fund is presently $24 billion in debt because politicians prevent it from charging such rates (they are about 50% of what they should be, according to the Congressional Budget Office).
Perhaps the most effective way to reduce greenhouse emissions is to make it less costly to build nuclear power plants that would displace coal-generated power (as China is starting to do). This can be done by revising regulations governing their construction and the disposal of their waste products. Evidence is accumulating that the “linear no-threshold” model of emission risk used by the U.S. Nuclear Regulatory Commission is needlessly conservative, scientifically questionable and adds significantly to the costs of building such plants and disposing of their waste. Coal plants are allowed to put out thorium and uranium emissions “far in excess of what nuclear plants are allow to emit,” according to Wall Street Journal columnist Holman Jenkins. Properly designed and managed, nuclear power plants and their waste storage systems should be the favorite children of the green crowd.
In other words, the most sensible and less costly policy responses to an upward trend in global temperatures are to do away with “top down” mandates, designed by control-driven politicians and bureaucrats, and to encourage “bottom up solutions” – by individuals, entrepreneurs, and established firms – with minimal financial subsidies and less regulatory overhead.