Study: Global Warming Does Not Cause Hurricanes

In this GOES-13 satellite image taken Wednesday, Sept. 6, 2017 at 7:15 a.m. EDT, and released by NASA/NOAA GOES Project, Hurricane Irma tracks over Saint Martin and the Leeward Islands. Hurricane Irma roared into the Caribbean with record force early Wednesday, its 185-mph winds shaking homes and flooding buildings on …
NASA/NOAA GOES Project via AP

Global warming has not caused an increase in the frequency or intensity of hurricanes, a study published by the Global Warming Policy Foundation has confirmed.

Climate alarmists such Michael Mann, Kerry Emanuel, and Al Gore often claim that hurricanes are among the extreme weather events that have been exacerbated by man’s selfishness, greed, and refusal to amend his carbon-guzzling lifestyle.

But there is “little evidence” that this is so, according to the study’s author Paul Homewood.

Even the alarmist Intergovernmental Panel on Climate Change (IPCC) acknowledged in its Fifth Assessment Report in 2013 that there has been little change in long-term hurricane activity:

In summary, [there is] low confidence that any reported long-term (centennial) increases in tropical cyclone activity are robust, after accounting or past changes in observing capabilities. More recent assessments indicate that it is unlikely that annual numbers of tropical storms, hurricanes and major hurricanes counts have increased over the past 100 years in the North Atlantic basin. Evidence, however, is for a virtually certain increase in the frequency and intensity of the strongest tropical cyclones since the 1970s in that region.

Unfortunately, a particularly severe hurricane season in the North Atlantic in 2017 gave the alarmists just the excuse they needed to cry wolf once more. Backed by footage of the devastation caused by that year’s two major landfalling hurricanes — Harvey and Irma — they concocted a plausible theory as to why global warming will increase such extreme weather events: hurricanes feed off warm waters, so the warmer the waters, the more intense the hurricane.

This theory, though, is confounded by real-world evidence:

The longest and most reliable database of hurricanes is of US landfalling ones. NOAA’s Hurricane Research Division has carefully reanalysed the original records of all hurricanes up to 1960. Its HURDAT database shows that there has been no increase in the frequency of hurricanes or major hurricanes (Category 3 and over) since the start of the record in 1851. Prior to Harvey, no major hurricane had hit the US since Wilma in 2005, the longest such period on record. In 2017, for instance, two major landfalling hurricanes – Harvey and Irma – hit the US, but this is not unusual. In 1893, for instance, there were three, a number repeated in 1909. The record year for landfalling hurricanes was 1886, when there were seven. Only
three Category 5 hurricanes have hit the US mainland: the Labor Day hurricane in 1935, Camille in 1969, and Andrew in 1992.

Data provided by HURDAT also shows that recent hurricane activity in the North Atlantic has not been unusual by historical standards. In 2017, there were six major Atlantic hurricanes, but the highest total recorded was eight in 1950. Of last year’s six, two were Category 5 – Irma and Maria – but again, this is not unusual, having occurred five times previously, including in 1932 and 1933.

Historical data shows that Atlantic hurricanes, particularly major ones, were much more common between about 1930 and 1960 than in the following three decades. Since 1990, the numbers have returned to the earlier levels. It is widely accepted that this pattern is linked to the Atlantic Multidecadal Oscillation (AMO), a natural reoccurring cycle of temperature changes in the sea surface temperatures.

A database of global hurricanes is kept, with data going back to 1970. This shows an increase in the number of major hurricanes and their accumulated energy between 1970 and 1993. This is associated with the AMO cycle too. Since 1993, there has been a decline in the frequency of all hurricanes, major hurricanes and accumulated energy.

In summary, there is little evidence that global warming has resulted in more hurricanes, or more intense ones in recent years. On the contrary, available evidence confirms that hurricane and major hurricane frequency has been similar in many prior periods.

Hurricane activity, in other words, is a cyclical weather event which has nothing to do with “man-made” climate change. Don’t let the alarmist #fakenews merchants tell you otherwise.

.