Comments on: So what happened to the 2007 hurricane season?

By: David

David — Fri, 30 Nov 2007 20:16:26 +0000

“Hurricane Felix set the Atlantic record for fastest intensification from the first advisory to a Category 5 hurricane. It took Felix just 54 hours to accomplish the feat.”

Of course you fail to mention that part of the reason is that comparing Felix to past category 5 hurricanes is an apples to oranges comparison:

When forecasters upgraded Hurricane Felix to a category 5 storm, it had a minimum pressure of 939 millibars. That’s nearly 20 millibars higher than the old Saffir Simpson scale which included designations for central pressure in addition to wind speeds. Frank: “We would have never called that a category 5 hurricane.”

Source. http://blogs.chron.com/ sciguy/ archives/ 2007/ 11/ is_the_hurrican.html

By: Joe

Joe — Fri, 30 Nov 2007 21:37:04 +0000

Interesting, but hardly earth-shattering.

By: Paul K

Paul K — Fri, 30 Nov 2007 22:49:58 +0000

Joe,
Good post. There is disagreement in meteorology about possible trends in hurricanes and the connection, if any, to global warming. It seems statistical analysis and nomenclature is having a hard time keeping up with ever increasing measurement capabilities. As you have pointed out, meteorology and climatology are very different sciences with often different conclusions.

By: paul m

paul m — Fri, 30 Nov 2007 23:07:41 +0000

With hotter/drier seasons we should get more dust - this will mean more chaotic patterns for hurricane activity. However, because of the hotter surface temps there will probably be very intense storms around.

By: Gary Herstein

Gary Herstein — Fri, 30 Nov 2007 23:42:30 +0000

A couple of question sets, actually:

My first constellation of questions: are there any predictors — either in place or in the pipeline — for dust effects on the Atlantic? I am guessing the answer is “no,” since if they were even partially in place they would be providing input into the hurricane precitions. (Alternatively, are there acurate dust predictors, albeit on a shorter time scale than that required by the seasonal hurricane predictions, such that one could not know in July, but could tell by early September, that the dust effects were taking control of the overall pattern?)

A second and related question set is this: are the dust factors principally from the Sahara (and hence, presumably related to the Levant &/or Sciroco) or are there other factors? If others, from which directions & sources do they typically flow? Or is this something that is itself genuinely global in character? (For example, dust from drought areas around the world, “Spanning the Globe”?)

Thanks!

By: TAR

TAR — Fri, 30 Nov 2007 23:55:15 +0000

With the Northern hemisphere tropical cyclone activity ACE index steadily decreasing since 2004 does that mean the dust from africa has been blowing for that long a period?

By: beefeater

beefeater — Sat, 01 Dec 2007 00:38:37 +0000

“So what happened to the 2007 hurricane season?”

Easy answer, it was unpredictable just like always. What happened to “Global Cooling” from the 70’s? Same thing. What will happen with “Global Climate Change”? Nobody knows for sure except that it will change, usually does, always has. So what’s the problem? That doesn’t sell books or get study grants.

By: Jay Alt

Jay Alt — Sat, 01 Dec 2007 04:46:20 +0000

Gary Herstein writes:
“are there any predictors — either in place or in the pipeline — for dust effects on the Atlantic? I am guessing the answer is “no,”

Dust is a new research focus that requires some patience. In 2006 NASA research aircraft from French bases in W. Africa showed a link between dust and a quiet period.

http://news.bbc.co.uk/1/hi/world/africa/6287995.stm

NASA review of 2006 season -
http://www.nasa.gov/ mission_pages/ hurricanes/ archives/ 2006/ normal_2006.html

For the 2007 season the flights and research were expanded. Predicting the occurance and extent of dust storms months in advance has never been done. Give them time to work on the problem.

http://www.engr.wisc.edu/ wiscengr/ feb07/ africandust.shtml

picture-
http://visibleearth.nasa.gov/view_rec.php?id=19784

By: Ron

Ron — Sat, 01 Dec 2007 17:56:35 +0000

The science is in its infancy and Gaia is a complex system. Give the scientists time to work.

By: Gary Herstein

Gary Herstein — Sun, 02 Dec 2007 00:54:06 +0000

Thanks for the dust info — which sounds like a snide phrase, but really isn’t. And I’m happy to give scientists time to work; I just knew that I did not know how much work had been done.

For example, one misunderstanding I had: I assumed knowledge about the link between dust and quiet periods in the atlantic basin was older than the data mentioned above.