Ryan N. Maue's Seasonal Tropical Cyclone Activity Update
Ului and Tomas are happily spinning away in the South Pacific. Considerable ACE is piling up -- March 2010 expected to be an above average month.
Has Global Warming Been Responsible for any Changes in Global Tropical Cyclone Frequency and Intensity? Bill Gray says (and I agree) No.
Link to Position PaperRecent arguments concerning global warming's influence on causing tropical cyclones (hurricanestyphoons) to become more frequent and more intense has been given much coverage in the media and by some published papers which claim a valid linkage. But observational data shows no such linkage. Despite the global warming of the sea surface that has taken place between the mid 1970s to the late 1990s and the general global warming of the last century, the global numbers of tropical cyclones and hurricanes and their intensity have not shown any significant trends except for the Atlantic where multi-decadal circulation variations in the ocean drive large multi-decadal variations in major hurricane (Cat 3-4-5) numbers.
Flashback to November 30, 2009 -- and my commentary on the Great Depression! Tropical Cyclone Energy near 30-year lows ... --> LINK to page
In light of the new Knutson et al. (2010) Nature Geosciences paper, I have more confidence in what I wrote. There are several highlights that I will update shortly...Climate Audit: Great Depression!
February 24, 2010: With El Nino raging on, there has been some development of Southern Pacific tropical cyclones with a few contributing considerable ACE to the Southern Hemisphere total. The Northern Hemisphere is quiet, as expected.
North Atlantic Hurricane Season ends -- > Houston Chronicle
November 30, 2009: With the official end of the 2009 North Atlantic hurricane season, it is time to put the season in perspective and compare to the past 70-seasons. In terms of the Accumulated Cyclone Energy index [ACE], 2009 tallied ~52 ACE points which is less than half of normal. Here is a listing of the past 70-years of ACE values for the North Atlantic Listing . 2009 was the quietest year since 1997 (ACE= 41) and the 16th slowest since 1940. Interestingly, 2009 saw 1/5th of the activity of 2005, the most active ACE season on record. 3 storms out of the total of 9 accounted for 85% of the total ACE (Bill, Fred, and Ida). These 3 storms were the only hurricanes out of the total 9 tropical storms.
Figure: Global and Northern Hemisphere Accumulated Cyclone Energy: 24 month running sum through Mar 5, 2010.
Note that the year indicated represents the value of ACE through the previous 24-months for the Northern Hemisphere (bottom line/boxes) and
the entire global (top line/boxes). The area in between represents the Southern Hemisphere total ACE.
Figure: Global hurricane days (64 kts +): 24-month running sums. Global hurricane days are at a 30-year low.
Figure: Global major hurricane days (96 kts +) : 24-month running sums.
2009-2010 Southern Hemisphere Tropical Cyclones
Maximum Wind Speed & ACE per storm (ATCF operational intensity estimates)
Maximum Wind Speed & ACE per storm (HURDAT + JTWC best-tracks)
Northern Hemisphere Tropical Storms during Calendar Year 2009 = 58
Northern Hemisphere Hurricanes + during Calendar Year 2009 = 26
The 13 Tropical Cyclones that had an ACE > 10 Account for almost 3/4 of the total Northern Hemisphere ACE. 7 (ACE > 24) account for more than 1/2 of the total NH ACE.
Southern Hemisphere Tropical CyclonesMaximum Wind Speed & ACE per storm (JTWC Best Tracks)
| 2008-2009 Asma (50 ACE=2.1675) Anika (60 ACE=1.8225) Bernard (40 ACE=0.565) Cinda (55 ACE=3.14) Billy (110 ACE=14.0475) Dongo (55 ACE=2.34) Charlotte (40 ACE=0.405) Eric (40 ACE=1.94) Fanele (115 ACE=8.0225) Dominic (50 ACE=1.1925) Hettie (35 ACE=0.3675) Ellie (35 ACE=0.49) Gael (120 ACE=19.285) Freddy (55 ACE=2.385) Innis (40 ACE=0.65) Hina (65 ACE=2.6625) Gabrielle (35 ACE=0.735) Hamish (135 ACE=24.0875) 19 (35 ACE=0.3675) Joni (55 ACE=2.97) Ken (50 ACE=2.23) Ilsa (100 ACE=12.22) Jasper (45 ACE=0.97) Izilda (45 ACE=2.6275) Lin (55 ACE=1.575) Jade (65 ACE=5.495) Kirrily (45 ACE=1.0175) Total Tropical Storms+ = 27 Total Hurricanes+ = 8 |
2007-2008 NONAME 01 (40 ACE=0.5275) GUBA (75 ACE=5.13) LEE-ARIEL (60 ACE=4.08) BONGWE (65 ACE=6.0425) DAMAN (110 ACE=10.5) CELINA (40 ACE=2.6) DAMA (50 ACE=2.2) MELANIE (60 ACE=4.165) ELNUS (40 ACE=1.94) HELEN (50 ACE=1.1825) ELISA (50 ACE=1.15) FUNA (105 ACE=9.94) FAME (85 ACE=6.6175) GULA (90 ACE=8.4725) GENE (100 ACE=15.6875) HONDO (130 ACE=28.715) NONAME (40 ACE=1.4225) IVAN (125 ACE=24.68) NICHOLAS (80 ACE=12.22) NONAME 20 (35 ACE=0.3675) OPHELIA (65 ACE=6.175) JOKWE (110 ACE=21.8675) KAMBA (115 ACE=10.8725) NONAME 24 (35 ACE=0.49) LOLA (35 ACE=0.98) PANCHO (100 ACE=9.0375) ROSIE (50 ACE=2.6625) NONAME (40 ACE=1.13) Total ACE = 201 |
2006-2007 XAVIER (115 ACE=9.625) YANI (70 ACE=3.1075) NONAME (45 ACE=1.8175) NONAME (35 ACE=0.245) BONDO (135 ACE=27.905) CLOVIS (65 ACE=5.2225) ISOBEL (40 ACE=0.65) ZITA (60 ACE=1.595) ARTHUR (65 ACE=3.0825) DORA (115 ACE=23.57) NONAME (35 ACE=0.3675) NELSON (50 ACE=0.82) ENOK (40 ACE=0.2825) FAVIO (105 ACE=4.1075) GAMEDE (105 ACE=19.1125) HUMBA (80 ACE=6.91) GEORGE (110 ACE=9.55) SH18 (75 ACE=5.8375) INDLALA (120 ACE=3.01) KARA (105 ACE=5.81) BECKY (70 ACE=3.88) JAYA (110 ACE=14.95) CLIFF (55 ACE=1.6925) PIERRE ( ACE=0) Total ACE = 153 |
2005-2006 NONAME (40 ACE=0.6875) NONAME (35 ACE=0.3675) BERTIE (115 ACE=18.245) NONAME (35 ACE=0.49) CLARE (60 ACE=2.985) TAM (40 ACE=0.6875) URMIL (60 ACE=1.6975) DARYL (50 ACE=2.6625) BOLOETSE (100 ACE=11.645) JIM (80 ACE=5.8175) VAIANU (75 ACE=6.59) NONAME (45 ACE=0.9325) KATE (45 ACE=0.645) CARINA (130 ACE=21.41) INVEST (35 ACE=0.245) DIWA (55 ACE=3.425) LARRY (115 ACE=6.04) WATI (80 ACE=8.3225) FLOYD (115 ACE=13.98) GLENDA (120 ACE=14.4625) HUBERT (55 ACE=2.275) ELIA (50 ACE=2.4125) MONICA (155 ACE=31.4325) Total ACE = 158 |
Last 30-years of SOUTHERN HEMISPHERE ACE ...AND... ENSO

MULTIVARIATE ENSO INDEX -- Wolter and Timlin (1998) Page Link
Seasonal ACE for the following years:
JTWC Best Track Data: 31-year 1978-2009 Seasonal Average ACE = 203
Southern Hemisphere
| SEASON | TOTAL ACE |
| 2008-2009 | 106 |
| 2007-2008 | 190 |
| 2006-2007 | 176 |
| 2005-2006 | 160 |
| 2004-2005 | 260 |
| 2003-2004 | 221 |
| 2002-2003 | 263 |
| 2001-2002 | 194 |
| 2000-2001 | 129 |
| 1999-2000 | 225 |
| 1998-1999 | 213 |
| 1997-1998 | 256 |
| 1996-1997 | 370 |
| 1995-1996 | 235 |
| 1994-1995 | 168 |
| 1993-1994 | 318 |
| 1992-1993 | 228 |
| 1991-1992 | 321 |
| 1990-1991 | 148 |
| 1989-1990 | 206 |
| 1988-1989 | 269 |
| 1987-1988 | 136 |
| 1986-1987 | 120 |
| 1985-1986 | 194 |
| 1984-1985 | 203 |
| 1983-1984 | 190 |
| 1982-1983 | 199 |
| 1981-1982 | 139 |
| 1980-1981 | 112 |
| 1979-1980 | 230 |
| 1978-1979 | 113 |

Figure. Yearly ACE for Southern Hemisphere Seasons September - April. JTWC best-tracks.
No significant trend
Data from IBTrACS
JTWC: List of ACE-per-storm --> Link95 3.61 100 4.0 105 4.41 110 4.84 115 5.29 120 5.76 125 6.25 130 6.76 135 7.29 140 7.84 145 8.41 150 9.00 155 9.61 160 10.24
One day at 100 kts = 8 days at 35 kts --- One day at 135 kts = 4.3 days at 65 kts
Review: 2008 Tropical Cyclone Activity
Western North Pacific Tropical Cyclones
Maximum Wind Speed & ACE per storm (JTWC Best Tracks)
| 2008 01W (40 ACE=0.405) NEOGURI (100 ACE=11.1575) RAMMASUN (135 ACE=16.9275) MATMO (40 ACE=0.4425) HALONG (75 ACE=4.695) NAKRI (125 ACE=20.4575) FENGSHEN (110 ACE=11.87) KALMAEGI (90 ACE=6.2575) FUNG-WONG (95 ACE=8.9725) KAMMURI (50 ACE=1.625) NONAME (35 ACE=0.245) VONGFONG (55 ACE=3.195) NURI (100 ACE=10.795) 14W (35 ACE=0.1225) SINLAKU (125 ACE=33.465) 16W (35 ACE=0.6125) 17W (35 ACE=0.245) HAGUPIT (125 ACE=14.385) JANGMI (140 ACE=22.195) MEKKHALA (55 ACE=1.1275) 21W (40 ACE=1.0075) 22W (35 ACE=0.3675) BAVI (45 ACE=1.05) MAYSAK (55 ACE=2.255) HAISHEN (40 ACE=0.4425) NOUL (40 ACE=0.6875) DOLPHIN (85 ACE=9.66) |
2007 KONG-REY (100 ACE=7.3675) YUTU (130 ACE=16.565) TORAJI (35 ACE=0.245) MAN-YI (125 ACE=20.005) USAGI (120 ACE=16.325) NONAME ( ACE=0) PABUK (70 ACE=4.2525) WUTIP ( ACE=0) SEPAT (140 ACE=29.6625) FITOW (80 ACE=19.84) DANAS (65 ACE=4.1475) NARI (125 ACE=11.2825) WIPHA (135 ACE=12.3875) FRANCISCO (45 ACE=0.7675) LEKIMA (70 ACE=5.3875) KROSA (130 ACE=24.5175) HAIYAN (50 ACE = 1.7525) LINGLING (40 ACE=0.97) KAJIKI (115 ACE=8.9575) FAXAI (40 ACE=0.405) PEIPAH (75 ACE=7.2175) TAPAH (35 ACE=0.49) HAGIBIS (80 ACE=7.8375) MITAG (95 ACE=14.785) |
2006 01W (35 ACE=0.735) CHANCHU (125 ACE=27.3125) JELAWAT (45 ACE=1.055) EWINIAR (130 ACE=28.5075) BILIS (50 ACE=3.8575) KAEMI (75 ACE=10.165) PRAPIROON (70 ACE=4.3675) SAOMAI (140 ACE=20.1475) MARIA (60 ACE=3.825) BOPHA (55 ACE=2.7425) WUKONG (55 ACE=4.5425) IOKE* (140 ACE=86.4025) SONAMU (45 ACE=1.21) SHANSHAN (120 ACE=23.4725) YAGI (140 ACE=29.505) XANGSANE (125 ACE=21.6725) BEBINCA (35 ACE=0.6125) RUMBIA (30 ACE=0) SOULIK (90 ACE=11.7275) CIMARON (140 ACE=23.705) CHEBI (125 ACE=11.56) DURIAN (135 ACE=24.9275) UTOR (100 ACE=13.24) TRAMI (30 ACE=0) *Note: IOKE began as CPAC system. Total ACE includes entire lifecycle. |
2005 KULAP (65 ACE=4.1525) ROKE (80 ACE=5.1775) SONCA (115 ACE=14.4725) NESAT (125 ACE=35.17) HAITANG (140 ACE=27.705) NALGAE (55 ACE=2.5275) BANYAN (60 ACE=4.585) WASHI (45 ACE=1.5825) MATSA (90 ACE=11.605) SANVU (65 ACE=2.83) MAWAR (125 ACE=24.37) GUCHOL (65 ACE=5.2525) TALIM (130 ACE=19.5125) NABI (140 ACE=36.065) KHANUN (115 ACE=14.39) VICENTE (50 ACE=1.5175) DAMREY (90 ACE=9.365) SAOLA (100 ACE=12.9675) LONGWANG (125 ACE=30.36) KIROGI (115 ACE=28.3725) KAI-TAK (85 ACE=7.2) TEMBIN (45 ACE=1.46) BOLAVEN (70 ACE=7.2875) 25W (45 ACE=0.89) |
Review: 2007 Tropical Cyclone Activity
During 2007, the Northern Hemisphere as a whole experienced the lowest ACE hurricane energy & number of hurricane days since 1977. 2007 was the 4th slowest year in the past half-century (since 1958)...Maue, R.N., 2009: Northern Hemisphere Tropical Cyclone Activity (in press: paper PDF).


