Hurricane Forecasters' 0-for-2 Record Reveals Limits of Climate Science

Posted: Dec 18, 2007 12:01 AM
Hurricane Forecasters' 0-for-2 Record Reveals Limits of Climate Science

With the official hurricane season now over, we now have a better idea of what 85%+ forecast certainty meant: Wrong 100% of the time.

In August, the National Oceanic and Atmospheric Administration (NOAA) forecast a 85% probability there would be an "above normal" hurricane season.

This is the second year running the government hurricane forecast was wrong. This 0-2 record may tell us something about other similarly "certain" forecasts, such as those issued by the U.N.'s Intergovernmental Panel on Climate Change.

If forecasters can't get hurricane projections right during hurricane season, why should we trust their forecasts for a hundred years from now?

NOAA had predicted 7-9 hurricanes and 3-5 major hurricanes, but there were just six hurricanes, only two of which were "major." There are "normally" six hurricanes, two major, and 11 named storms.

The sixth hurricane came only three days before the official end of the hurricane season, when NOAA's National Hurricane Center (NHC) quietly upgraded tropical storm Karen to hurricane status. The timing of the re-designation - at the moment hurricane season post-mortems were already running in newspapers throughout the country - may have struck some as a bit suspicious.

But National Hurricane Center spokesman Dennis Feltgen insists that the timing was purely coincidental.

"Its re-classification was not related to any particular time of the season," Feltgen told me. "NHC specialists are consummate professionals and would never name (or not name) a tropical cyclone for the sole purpose of verifying a product."

He was not able to cite another example, however, when such a re-classification came so close to the end of the season.

Even with Karen's change in status, the hurricane season was unusually quiet. The Accumulated Cyclone Energy (ACE) Index, which measures storm duration and intensity, was just 70.54 this year, more than 20% below the median and a little over half of what NOAA predicted. Hurricanes Lorenzo and Humberto both had lower ACEs than any tropical storm in 2006, and the season's overall ACE - including the two category 5 hurricanes - was still less than the ACE of 2004's Hurricane Ivan all by itself.

NOAA did get the number of named storms right: There were 15 this year, four above what the agency considers normal and in the middle of the range projected. Unfortunately, "normal" doesn't mean a great deal.

For one thing, NOAA has changed the criteria for naming storms - most recently in 2002, when subtropical storms were named for the first time.

For another, only subtropical storms, tropical storms and hurricanes that are identified as such while they're occurring are named. Last year, one storm that should have been named was overlooked. In 1964, three tropical cyclones - equal to a quarter of such storms that year - weren't named.

And finally, there are vast differences in the quality of data available to NOAA over time, which makes "normal" difficult to ascertain.

NOAA's forecast last year was similarly dire - and even more off-target.

One wonders about the level of certainty bandied about by global warming forecasters.

The IPCC says it is very likely (greater than 90% certain) that precipitation in high latitudes will increase, the frequency of heat waves over most land areas will rise and the meridional overturning circulation (MOC) will slow during the 21st century. Slowing of the MOC is of particular concern, as it is the process that permits the ocean's warm upper waters to be transported to the far north and cool deep waters to be returned toward the equator resulting in more moderate climates.

If the IPCC's projections are anything like NOAA's, we have nothing to worry about.

Global warming alarmists have exploited NOAA and IPCC forecasts to frighten the public in hopes of increasing public support for economically-ruinous caps on U.S. carbon emissions.

The World Wildlife Fund, for example, says global warming is putting "hurricanes on steroids," but that's only true if they're referring to one of the side-effects of long-term steroid use - impotency.

Unfortunately, NOAA is helping fuel the scare campaign through its annual forecasts and its reports of storm and heat "records" -- records the agency knows it has no way to verify.

The count of tropical storms, for example, would have increased dramatically even if actual storm activity had not increased, because our ability to monitor weather is constantly improving.

The Quick Scatterometer, a satellite that measures the ocean's surface winds, was launched just eight years ago. It produces more than double the daily measurements of its predecessor, launched just three years earlier, which itself had increased by more than 100 times the amount of ocean wind information reported from ships.

Increased resources and technological advancement across the board - from that used in satellites to Hurricane Hunter aircraft - means we are identifying storm systems we wouldn't have known about in the past.

Hurricane Karen is a good case in point. NHC estimates that Karen reached a maximum speed of 65 knots per hour (or 74.9 miles per hour) - only about 1.2 mph above tropical storm status. No direct measurement of the storm's wind speed was taken. Instead, an estimate was made based on satellite imagery and data from Hurricane Hunter aircraft using state-of-the-art Stepped-Frequency Microwave Radiometer (SFMR) technology taken six hours after Karen started losing strength. The Hurricane Hunter aircraft had only been equipped with the SFMR this summer.

Even if NHC's extrapolation of the data is correct - and 1.2 mph leaves little room for error - it's unlikely that Karen would have been classified as a hurricane in years past.

NHC's Feltgen ducked a specific question on this, but indirectly conceded that it was possible.

"Technology such as satellites and the SFMR has allowed forecasters to detect... several tropical cyclones that might have otherwise gone undetected in the past," Feltgen said. "In addition, the technology also permits a more accurate measurement of the storm intensity."

NOAA doesn't mention its changing criteria for naming storms, nor the vast differences in data quality over time, when it issues annual hurricane season forecasts. Yet it continues to portray these forecasts and subsequent storm reports in a historical context, as if what it is saying is meaningful.

It holds no meaning in science, but may in political science.

If NOAA continues to dabble in politics, Americans should afford it all the respect it does to politicians...

...very little.