Northern hemisphere tropical cyclone activity lowest in 30 y

[Crostorm]

Despite the hyping of “climate change” leading to a greater occurrence of tropical storms, the northern hemisphere is actually experiencing the lowest tropical cyclone activity in the last 30 years. A study recently completed by Florida State University shows that while North Atlantic activity is above normal this year, overall the hemisphere is experiencing considerably fewer than normal storms.

In 2008 we have all watched Hurricane Ike and others strike the Gulf Coast region. However, the 2008 season currently is headed to finish at half the number of storms that the record 2005 season that brought Hurricane Katrina. This is in comparison to the Western and Eastern Pacific basins that are seeing considerably fewer than normal hurricanes and typhoons.

The chart below shows the northern hemisphere activity in blue in comparison to global activity in green.


http://www.examiner.com/x-219-Denver-We ... n-30-years

http://www.coaps.fsu.edu/~maue/tropical/

[Aslkahuna]

This was mentioned in the Tropics Section. However, lower numbers of Tropical Cyclones do not of necessity invalidate the idea of Climate Change since a number of GCMs and some research indicates that GW would in fact result in fewer Tropical Cyclones globally though the overall intensity might increase. How this would affect the ACE globally would depend upon how much fewer the numbers of storms would be but at the very least it would result in a no change scenario and could easily result in a decrease.

Steve

[Tampa Bay Hurricane]

Must have to do with PDO/NAO or something like that...about global warming
I have no idea.

[Ed Mahmoud]

There seems to be a tendency of slow Atlantic years being active Pacific years, and vice versa, and since the Pacific is much larger, a slow Pacific year affects the numbers more.

[x-y-no]

There seems to be a tendency of slow Atlantic years being active Pacific years, and vice versa, and since the Pacific is much larger, a slow Pacific year affects the numbers more.

Indeed. It will be interesting to see what happens with the global numbers next time we have a significant El Nino.

I for one, have always argued that any correlation between global warming and tropical cyclone activity is suspect. Cyclogenesis is so much more complex than merely high oceanic heat content and a more energetic environment could quite reasonably be expected to exhibit more vertical shear on average.