2 year climatology

[Hurricanehink]

I was bored and decided to look up some more stats!

Here are the top ten back-to-back seasons on record, in terms of tropical/subtropical storms.
1) 2004/2005 with 43 (28 in 2005 and 15 in 2004)
2) 2006/2005 with 39 (largely due to 2005's)
3) 2011/2010 with 34 (19 in 2010 and 15 in 2011)
4) 1933/1932 and 1934/1933 with 32 (largely due to 1933's)
6) 1996/1995 with 32
7) 1887/1886 with 31
8) 2004/2003 and 2008/2007 with 31
10) 2001/2000 with 30

In terms of hurricanes, 2011/2010 has 15, which is tied for 24th. So, the number of named storms is impressive, but not so much the hurricanes.

[Hurricanehink]

In terms of major hurricanes, there have been 7 in 2010 and 2011, which is tied for 20th. In terms of accumulated cyclone energy (or ACE), the back-to-back season total is 238, which is 31st.

[Hylian Auree]

Awesome, 2010-2011 already at third. Thanks for the stats Hink <3

[Hurricanehink]

Per my other topic (odds of Going Greek), it's possible that it could get bumped up to 2nd. It would need six storms, which has happened in 7 of the past 16 years (44%). Five storms would tie it, which has happened in 9 of the past 16 years (56%).

[Ptarmigan]

Interesting stats. 2003 to 2005 was an active period.
59/31/16
ACE=647
ACE/Storm=11.6

[AJC3]

Interesting stats. 2003 to 2005 was an active period.
59/31/16
ACE=647
ACE/Storm=11.6

I threw together some figures on seasons with the lowest ACE/storm (based upon Wikipedia)
http://en.wikipedia.org/wiki/Accumulated_cyclone_energy

Lowest: 1970 (3.4 ACE units/Storm)
1972 (4.0 A/S)
1977 (4.2 A/S)
1977, 1983, 1991 (4.25 A/S)
1968 (4.375 A/S)
1994 (4.6 A/S)
1993 (4.75 A/S)
1982, 2007 (4.8 A/S)
1987 (4.85 A/S)

With the naming of Philippe, 2011 has dropped (for now) from about 5.1 to 4.8 ACE units/Storm, but will drift back up toward 5 (A/S) once again in the coming days with Ophelia and Philippe still active.

Another couple of fun factoids: The 2011 season has 16 NS thus far with a woeful total of a little over 77 ACE units. The lowest total ACE for another season with 16 or more NS is 2008 (16/8/5) with 144 ACE units, nearly twice as much. The previous year, 2007, saw 15 NS/6H/2MH and only 72 ACE units, quite similar to this season (16/3/2) in having a large number of NS, yet a very low ACE (at least thus far)

[Cranica]

The combination of those two would imply that, in the past, the intensity of storms in a given year was strongly correlated with the number of storms, probably due to some environmental condition favoring both - and for whatever reason, this year is favoring storms but without high intensity. I'd be interested in a comparative study between, say, this year, 2005, 1995, and other active years to see if one could find a smoking gun.