Oscillations, Tropical

Where Are the Hurricanes?

2006 has had a surprisingly slow hurricane season considering that it’s part of the active phase of the Atlantic Multidecadal Oscillation. Tropical Storm Florence is currently spinning in the Atlantic, flirting with the East Coast (but probably won’t make the commitment). Compare this with last year, when we were past the now infamous “K” name, and with 2004, which had already had two Category Four storms and a Category Five (Ivan) brewing.

Every single storm this year has struggled, from the smallest disturbance to the (so far) most powerful system of the year, Category One Hurricane Ernesto. They all experienced dry air and strong shear, which hindered development despite the overall warm sea surface temperatures that I have been documenting since May. Meanwhile, activity in the Pacific Basin has flourished; the eastern part of it is on the “K” name (Kristy). What’s causing this?

Well, the answer appears to be that meteorological boogeyman associated in the public mind with weird weather and general weather-related misfortune: El Niño. Meteorologists are starting to come to agreement that we are entering an El Niño and that it will impact the winter weather this year, as well as the remainder of the hurricane season. What doesn’t it impact?

Hmm…

Well, the weird thing is that Atlantic sea temperatures remain very warm. The Gulf of Mexico is warm enough to support a storm like Hurricane Camille (which had 200 mph winds), and much of the Atlantic can support a major hurricane. Ordinarily, El Niño is accompanied by cooler-than-normal Atlantic temperatures as well as unusual prevailing wind patterns that destroy tropical systems. The winds are there, but not the water temperatures. I wonder if global warming has caused our oceans to remain warmer than normal (whether for El Niño, La Niña, or neutral) for longer than normal. Thus far, this active hurricane cycle, which began in 1995, has had two strong El Niño years: 1997 and 2002. 2004’s hurricane season was cut short by a weak El Niño that developed late in that year, but only 1997 and 2002 experienced a powerful event. In both years, sea temperatures dropped with the onset of the El Niño conditions.

It’s something to think about.

Tropical

Gulf Goes Nuts

July 19, 2005

July 19, 2006

That, I think, says it all.

This is exactly what worries me about this hurricane season. The entire Gulf can support a Category 5 now, and the East Pacific, despite being slightly cooler than the Gulf, has already produced the powerful Category Four Hurricane Daniel.

The rest of the ocean isn’t quite this warm, but it doesn’t really matter. As an example, Katrina entered the Gulf as a minimal hurricane and became a Category 5 as a direct result of low shear and boiling temperatures without entering any other body of water. Here is what the water temperatures looked like before Katrina’s entrance (using the same scale as the previous pictures):

The Gulf is clearly well on its way to this level.

The Gulf Coast, as battered as the infrastructure may be, must do something in preparation, and soon. There are people who still need housing. There are communities still struggling after Katrina. Parts of New Orleans remain a war zone.

Unless this season is extremely unusual, some spot on the Gulf Coast is likely to take a major hurricane strike in 60 days or less.

Please. Nobody wants to see yet another catastrophe.

Tropical

Gulf of Mexico resumes rapid warmup

For awhile, the seasonal warming of the Gulf of Mexico didn’t keep pace with the warming of 2005 (at the same time of year). That appears to have changed. It’s no real surprise, with temperatures near the Coast approaching 100 degrees in places and record highs being set on an almost-daily basis (the old records mostly having been set last year or over the past decade).

June 21, 2005: June 21, 2006:

Different regions are warming, definitely… and in fact, I’d recommend a comparison of June 2005 and June 2006. At this point last year, the Gulf was in a brief cooling trend. This year, it is in what can only be described as explosive warming.
June 2005 June 2006

(In other, completely, wholly unrelated news, yet another scientific study backs up the idea of human-induced explosive global warming.)

BTW, minor props to me for calling Alberto. Didn’t quite make hurricane status, nor do I expect it to be upgraded retroactively at the end of the season, but not too bad. At the end of the season, I’ll look over my various predictions and see how accurate they were overall.