The global warming debate has developed a pattern: In part A, a scientist makes a scary claim and gets headlines for himself, and his funding source, across the known world. In part B, a few months later new evidence blows the scary claim away—but with no press coverage of its demise.
Two more global warming scares have just been quietly blown away: the claim that global warming is causing more and bigger hurricanes; and the claim that warming threatens to shut down the great Atlantic Ocean conveyor currents.
In the wake of Katrina, the message that global warming was producing more and bigger hurricanes led the news on TV and the front pages for weeks. Now, the journal Science has published a reanalysis of the recent global hurricane data.
When the data were analyized on a uniform framework of space and time, the regions that get 85 percent of the howling tropical storms show no upward trend in storm energy released. Some even show small declines. The Atlantic is the only region showing an increase, with a doubling of storm energy between the 1980s and the last decade. However, the Atlantic increase is globally canceled out by the North Pacific, where storm energy releases dropped 60 percent.
James Kossin of the University of Wisconsin led the reanalysis of the tropical storms. He says there’s no sign that tropical storms are intensifying globally as the ocean waters warm. This is further endorsed by the old British Navy records from the Caribbean, which indicate more than twice as many major land falling hurricanes per decade during the Little Ice Age years from 1700 to 1850 as during the last 50 years of global warming.
The Abrupt Global Cooling Scare has also been discredited. In 2004, researchers had moored 19 new buoyant, instrument-laden cables from West Africa to the Bahamas, to get better long-term data on the conveyor currents. In the process, they also took a “snapshot” of north-south current flows and compared them with similar “snapshots” dating back to 1957. Horrors, the snapshot showed a 30 percent drop in the northward flow of the Atlantic currents over 47 years!
That conclusion was headlined, along with the scary scenario of a Gulf Stream collapse like the one that threw the world back into Ice Age temperatures 12,000 years ago. Now, however, several years of data from the instrument-laden floating cables are telling us that the 30 percent drop in current flow is within the conveyor’s normal variability. Oops. As Science said, “False alarm.”
Even the global climate models knew better. The big Goddard Space Institute climate model found that without melt-water from the huge mile-thick ice sheets that covered Canada and Northern Europe during the Ice Age, the Atlantic currents showed a safe and sane linear response to further warming.
Keep this “scare-now and discredit-later” pattern of global warming press releases firmly in mind for the future. Weather is highly variable, and the climate’s constant changes only reveal trends over long periods—but the global warming scare tactics have wrung $18 billion out of recent federal budgets for climate change research.
Remember, too, that hundreds of research studies in recent decades have found a moderate, natural 1500-year climate cycle that explains the earth’s pre-industrial 0.5 degree C warming from 1950 to 1940, and may also explain much of the very modest 0.2 degree C net warming since 1940. If increased atmospheric CO2 has produced nothing more than 0.1 degree or so of warming in the last 65 years, we may need to rethink the whole global warming issue.
Dennis T. Avery is a senior fellow for Hudson Institute in Washington, DC and the Director for Global Food Issues. He was formerly a senior analyst for the Department of State. Readers may write him at Post Office Box 202, Churchville, VA 24421.