Severe hurricanes, or tropical cyclones as they are known by those living outside the United States, are the most intense storms on the planet. Given the amount of damage they can inflict, it’s no wonder that they often are the poster children for the global warming movement—think Hurricanes Andrew, Katrina, and Sandy. Whenever and wherever they occur, you can count on some climate lobbyist telling us that storm was caused, or made worse, by global warming. Indeed, it is a green legend that carbon-induced global warming will cause more frequent or more severe tropical cyclones in the future, resulting in escalating economic damages.
Is that really so? A new scientific study addresses this topic, by Dr. S. Niggol Seo of the prestigious University of Sydney. He examined trends in tropical cyclones affecting Australia and published his results in the academic journal Environmental and Resource Economics.
Writing as background for his work, Seo states that alarming predictions of more intense hurricanes because of climate change “are of great concern,” yet he says there have been “few TC [tropical cyclone] studies in the Southern Hemisphere,” adding that there has been “no economic assessment of damages in the past.” Based on detailed reports of TCs that were generated in the Southern Ocean and hit Australia since 1970, from the Australian Bureau of Meteorology, Seo constructed damage estimates “using the reported financial loss, destruction of houses and capital goods, and losses of agricultural crops and livestock after a careful examination of the detailed individual cyclone reports,” which also included “local area income and population density where the storm hit.”
Seo’s examination of tropical cyclone data back to 1970 is important, because over that time (1970–2006) the carbon dioxide (CO2) concentration of the atmosphere rose by 55 parts per million (ppm), or more than half of global CO2 increase experienced since the dawn of the Industrial Revolution. In addition, global temperatures over this 36-year period rose by approximately 0.5°C, to levels that some (controversially) consider unprecedented in the last two millenia. If there is a period of time in which one should be able to find a CO2/temperature-induced signal in the tropical cyclone record, the years examined by Seo would seem to be it.
Despite this alignment of the stars, so to speak, Seo’s work fails to support claims that global warming is causing or will cause more frequent and severe tropical cyclones.