Don’t blame climate change for extreme weather
Climate change means more extreme weather: This is a simple, powerful claim that has been pounded into our consciousness for a decade.
From Greenpeace to President Obama to Scientific American, scarcely a weather event happens without someone pointing the finger at global warming and calling for action.
But there are big problems with this simple statement, which are exposed starkly in recent peer-reviewed analysis in the journal Weather, Climate and Society by University of Manchester scientists Vladimir Jankovic and David M. Schultz.
Citing the work of the Intergovernmental Panel on Climate Change, the United Nations’ global panel of climate change experts, Jankovic and Schultz find that “not all extreme weather events will change, nor will some of the changes — if they even occur — be detectable.” They note that some extreme events are expected to become less frequent but become more intense. Some areas of the globe will benefit; others stand to lose.
The reality is very different from the sloganeering. The researchers find “the soundbite of ‘climate change means more extreme weather’ is a massive oversimplification — if not misstatement — of the true state of the science.”
Global warming, in general, will mean higher temperatures. But it will increase temperatures most during winter, at night, and in cold places.
Droughts are among the most costly natural disasters and are often linked with climate change. But a comprehensive study in Nature shows that, since 1982, examples of all categories of severity of drought, from “abnormally dry” to “exceptional drought,” have not increased but have actually slightly decreased.
Heat waves are another big concern, and global warming will certainly result in more of these. But it will also mean fewer cold waves. Since many more people die from excessive cold than excessive heat, it is likely that fewer people will die altogether.
Let’s look more closely at the hurricanes that drive so much of our climate conversation. In the United States, damage costs from hurricanes are indeed increasing — but this is because there are more people, with more-expensive property, living nearer to coastlines.
In Florida, Dade and Broward counties alone are home to more people today than lived in 1930 in all 109 coastal counties from Texas to Virginia, along the Gulf and Atlantic coasts. Not surprisingly, that means much more damage. If we adjust for population and wealth, hurricane damage during the period 1900-2013 actually decreased slightly.
Looking into the future, it’s likely that hurricanes will become somewhat stronger by the end of the century. They will also likely become less frequent, and societies will definitely become more robust. A respected Nature review shows that hurricane damage currently costs 0.04 percent of global GDP. Accounting for an increase in prosperity, this would drop four-fold to 0.01 percent by 2100. But the global warming factor making hurricanes fewer but stronger will mean total damage will end around 0.02 percent. This shows that global warming is a problem, but it also shows us that, even accounting for this, damages will decline.
Yet when we see a hurricane we’re told to cut CO2. As Robert Redford distills it, we need to “reduce the carbon pollution that’s fueling these storms.” The problem is that we are being pointed in the wrong direction.
Climate policies will do little at a high cost. My peer-reviewed research published in the journal Global Policy shows that — even if maintained throughout the rest of the century — all of the Paris Climate treaty’s 2016-2030 promises on cutting carbon-dioxide emissions will cut global temperature increases by just 0.3 degrees Fahrenheit. Yet the cost will run from about $1 trillion to $2 trillion per year for the rest of the century.
Spending 1-2 percent of GDP on climate policies would, at best, help avoid much less than 0.01 percent of GDP lost to hurricanes. That is perhaps one-tenth of one cent back on the dollar. That is an infuriatingly bad investment.
Jankovic and Schultz warn that the overselling of climate impacts on extreme weather risks “reducing scientific credibility.” It “masks the social causes of hazard and, consequently, fetishizes climate change into a sole-source danger.” In short, a blinkered focus makes us forget that the vast amount of damage comes from societies being unprepared.
This matters to the unprepared communities from New Orleans to New York. We help them best by focusing on infrastructure, such as more secure levees and subway storm covers.
The stakes are much higher when it comes to poorer nations. Poverty is the biggest risk factor when it comes to hurricanes: If you’re poor, you will have a less sturdy house, and nowhere to go. A hurricane hitting Florida kills maybe dozens of people and creates some destruction. But in worse-off countries like the Philippines or Nicaragua, thousands die and the economy is destroyed.
Helping these places by cutting CO2 might feel good to rich world donors but will do almost nothing, despite the high cost. In the short run, we must help construct better shelters, levees, and seawalls, and develop better warning systems, evacuation plans, and emergency relief. We need to be more stringent about the way land can be zoned and used in coastal areas and strengthen building regulations and laws. Above all, we need to build more resilient communities.
In the long run, we should ensure that those in need emerge from poverty, so they can move from being vulnerable to being well-protected.
Climate change itself will be tackled not through expensive, inefficient carbon cuts, but by investing in research and development of green energy sources to make them so cheap they will outcompete fossil fuels.
But to help with impacts from extreme weather, we need to focus on adaptation and poverty. It may not make for a neat slogan, but it would be much more helpful.
Bjorn Lomborg is president and founder of the Copenhagen Consensus Center and a visiting professor at Copenhagen Business School.