November 30th marks the official end of hurricane season. Below is some good news, courtesy of Ryan Maue at Florida State University COAPS :
The 2007 Atlantic Hurricane season did not meet the hyperactive expectations of the storm pontificators. This is good news, just like it was last year. With the breathless media coverage prior to the 2006 and 2007 seasons predicting a catastrophic swarm of hurricanes potentially enhanced by global warming a la Katrina, there is currently plenty of twisting in the wind to explain away the hyperbolic projections. The predominant refrain mentions something about “being lucky” and having “escaped” the storms, and “just wait for next year”.
Before we prepare for the obvious impending onslaught of the next “above-average” hurricane season, let’s review some very positive aspects of what 2007 offered:
- The 2007 Atlantic Hurricane season was below-normal and tied for 2002 as the most inactive since the El Nino depressed 1997 season in terms of storm energy. Note: Hurricane Energy is measured through the Accumulated Cyclone Energy (ACE) index
- The North Atlantic was not the only ocean that experienced quiet tropical cyclone activity. The Northern Hemisphere as a whole is historically inactive. How inactive? One has to go back to 1977 to find lower levels of cyclone energy as measured by the ACE hurricane energy metric. Even more astounding, 2007 will be the 4th slowest year in the past half-century (since 1958) .
- Fewest Northern Hemisphere Hurricane Days since 1977. 3rd Lowest since 1958 (behind 1977 and 1973). See the Hurricane Days Graphic below.
- When combined, the 2006 and 2007 Atlantic Hurricane Seasons are the least active since 1993 and 1994. When compared with the active period of 1995-2005 average, 2006 and 2007 hurricane energy was less than half of that previous 10 year average. The most recent active period of Atlantic hurricane activity began in 1995, but has been decidedly less active during the previous two seasons.
When combined, the Eastern Pacific and the North Atlantic, which typically play opposite tunes when it comes to yearly activity (b/c of El Nino), brushed climatology aside and together managed the lowest output since 1977. In fact, the average lifespan of the 2007 Atlantic storms was the shortest since 1977 at just over two days. This means that the storms were weak and short-lived, with a few obvious exceptions.
Hurricane Days by Year
2007 Departure from ACE and Climatic norms:
|Basin||Current ACE||Climo ACE||% Departure|