The United Nations is misusing statistics to try and prove a causal relationship between the reported increase in carbon dioxide concentrations and the purported increase in extreme hurricane events over the last several decades, focusing in particular on the 2017 Atlantic hurricane season. “Over the past 30 years, the number of annual weather-related disasters has nearly tripled, and economic losses have quintupled,” UN Secretary General Antonio Guterres said at a press briefing on Wednesday. To “prove" his point, graphs were distributed to reporters that show carbon dioxide concentration levels and ocean temperatures rising since 1960, together with an increase in the number of meteorological natural disasters. “Scientists are learning more and more about the links between climate change and extreme weather,” the Secretary General added. He then predictably called for “countries to implement the Paris Agreement [on climate change], and with greater ambition.”
The UN is using the familiar logical fallacy of equating statistical correlations with proof of causation. The National Oceanic and Atmospheric Administration’s Geophysical Fluid Dynamics Laboratory issued a report, last revised on August 30, 2017, that demonstrates the crucial difference between mere statistical correlation and proof of causation. The report found that “records of Atlantic hurricane activity show some correlation, on multi-year time-scales, between local tropical Atlantic sea surface temperatures (SSTs) and the Power Dissipation Index (PDI),” which is “an aggregate measure of Atlantic hurricane activity.” However, the report went on to conclude that it is “premature to conclude that human activities–and particularly greenhouse gas emissions that cause global warming–have already had a detectable impact on Atlantic hurricane or global tropical cyclone activity.” Computer models may indeed predict increased storm intensity and destruction by the end of this century based on some measures of historical data showing increases in sea surface temperatures. However, the extent to which this would be due to an increase in 21st century greenhouse warming caused by human activity is indeterminate at the present time.
Moreover, even the statistical correlations may be misleading. The report examined records of past Atlantic tropical storm or hurricane numbers (1878 to present), which it found to be incomplete in terms of reported storms prior to 1965. Reliance on ship-based observations during that period meant that some storms, particularly short-lived ones, were simply overlooked because they had less opportunity for chance encounters with ship traffic. There were no satellites more than five decades ago to observe and measure hurricanes with the same degree of accuracy as can be performed today. Even with the sketchier information we do have regarding hurricanes in the latter part of the nineteenth century and the early part of the twentieth century, we know that five of the eight seasons with the most major hurricanes since 1851 occurred prior to 1965. The strongest hurricane on record to hit the U.S. occurred on the Florida Keys on Sept. 2, 1935. And while Hurricane Maria was a tragically devastating hurricane to be sure, Puerto Rico suffered an even worse hurricane in 1928.
“In summary,” the Geophysical Fluid Dynamics Laboratory report stated, “neither our model projections for the 21st century nor our analyses of trends in Atlantic hurricane and tropical storm counts over the past 120+ yr support the notion that greenhouse gas-induced warming leads to large increases in either tropical storm or overall hurricane numbers in the Atlantic.”
Christopher Landsea, who was the science and operations officer at the National Hurricane Center in 2010, observed that hurricanes run in cycles. "The late nineteenth century was a very busy period," he said. "Then from the 1900s until about 1925, it was very quiet. The late 20s to the 60s were very busy. The 1970s to the mid-90s were quiet again, and then from the late 90s onward, it's been generally very busy."
With respect to natural disasters and their aftermath, the United Nations is at its best when it works to deliver humanitarian aid to devastated areas. “To date,” according to Secretary General Guterres, “the United Nations and its partners have provided a variety of humanitarian assistance to the Caribbean region by air and by sea: 18 tons of food; 3 million water purification tablets; 3,000 water tanks; 2,500 tents; 2,000 mosquito nets and school kits; 500 debit cards for cash assistance; and much else.”
The United Nations is as its worst when it politicizes natural disasters such as the recent hurricanes and seeks to squelch any divergence from the conventional wisdom. “I have not yet lost my hope that what is happening will be making those that are still skeptical about climate change to be more and more realizing that this, indeed, is a major threat for the international community at the present moment,” the Secretary General told reporters. He wants the Paris Agreement to be strengthened. He said, “what is important is that the Paris Agreement is the solid foundation to allow us to have the ambition to go further and to make sure that we do not have a warming of the planet at the catastrophic levels that would happen if we'd just move on as we are.”
The true science deniers, which include the UN bureaucracy and its leaders, are those who try to shut down legitimate scientific skepticism regarding demonstrable misuse of data to mislead on storm causation and over-reliance on unvalidated computer models to support the political agenda behind the Paris Agreement. Even the UN itself admitted back in 2007 the shortcoming of its models: "In climate research and modeling, we should recognize that we are dealing with a coupled nonlinear chaotic system, and therefore that the long-term prediction of future climate states is not possible." However, the UN is institutionally incapable of resisting the prospect of hundreds of billions of dollars a year or more of wealth redistributed from richer nations to the less developed nations under its aegis, premised on the predictive power of just such models. President Trump has good reason to want a do-over when it comes to the Paris Agreement and the "green" financial commitments made by Barack Obama.