Researchers at the National Center for Atmospheric Research have calculated that "global warming accounted for around half of the extra hurricane-fueling warmth in the waters of the tropical North Atlantic in 2005, while natural cycles were only a minor factor." Their study will be published in the journal Geophyiscal Research Letters next week. Other researchers have argued that the recent increase in Atlantic hurricane activity can be traced to natural shifts in the Atlantic multidecadal oscillation. The NCAR researchers conclude that the AMO can account only for a small portion of the increase in the sea surface temperatures that boost hurricane strength.
The NCAR press release is here.
The NCAR findings also contrast with another study on trends in hurricane strength in GRL to which I linked in my review of An Inconvenient Truth. Published in May, that study found "based on data over the last twenty years, no significant increasing trend is evident in global ACE [accumulated cyclone energy] or in Category 4-5 hurricanes."
Science marches on–just as it should.