Variability of tropical cyclone activity Suzana J. Camargo Lamont‐Doherty Earth Observatory Columbia University
WWOCS, 16‐21 August 2014, Montreal, Canada
Outline • TCs and climate modes • MJO & TCs • ENSO & TCs • TCs & other climate modes • TC Decadal Variability • Future perspective References: Camargo et al. 2010, in “Global Perspectives on Tropical Cyclones”, eds. Chan & Kepert. Camargo & Hsiang, 2014, in Extreme Events: Observations, Modeling and Economics", AGU Monograph, in press.
History ENSO:
MJO:
El Niño‐Southern Oscillation
Madden‐Julian Oscillation
Monthly Weather Review, 1979, 1983
Journal of the Meteorological Society of Japan 1988, 1994
Climate Modes MJO
Equatorial Waves: TD type (easterly waves), equatorial Rossby waves, Kelvin waves, mixed Rossby‐gravity waves Frank & Roundy 2006; Roundy 2012
QBO AMM IOD
ENSO
AMO PDO
Tropical Cyclones and MJO
MJO index: Wheeler & Hendon 2004
GPI and OLR Anom. Composites ‐ JFM
First Position Anomaly Composites - JFM
Camargo, Wheeler & Sobel, JAS 2009
Global impacts of MJO on TC activity Changes in ACE by MJO phase
Klotzbach, J. Climate 2014
Models: TC – MJO connection NASA GISS model Kim et al. J. Climate 2012
ECMWF model Vitart, GRL 2009
Contribution of MJO and Equatorial Waves to TC Genesis
Schreck et al. MWR 2012
Current intra‐seasonal TC forecasts Week 1
Week 2
Dynamical Forecasts: ECMWF 32‐day ensemble Tsai et al. Asia‐Pacific JAS 2013
Week 3
Week 4
Statistical Forecasts CSU 2 week forecasts: Klotzbach & Gray, CSU http://tropical.atmos.colostate.edu
Leroy and Wheeler, 2008 Metéo France: www.meteo.nc/espro/previcycl/cyclA.php
Paul Roundy, SUNY Albany Frank and Roundy, 2006 Roundy and Schreck, 2009 http://www.atmos.albany.edu/ facstaff/roundy/tcforecast/tcforecast.html
Simulation and forecasting MJO • Systematic relationship between model mean state bias and MJO simulations (Kim et al., J. Climate 2011) • Global and local MJO forecast skill (Fu et al. Clim Dyn, 2013, Ling et al., MWR 2014) • Improvement in the TC‐MJO representation in models (Fu et al., Clim Dyn, 2013)
Tropical Cyclones and ENSO • Most well known and explored relationship • ENSO modulation of TC activity in all basins • ENSO impacts on TC activity have different characteristics in each TC basin: – Frequency – Location (genesis, tracks) – Intensity – Duration
Global Impacts of ENSO on TC activity
Genesis Potential Index
Observed Track Density
Camargo, Emanuel & Sobel, J. Climate 2007
Atlantic Hurricanes and ENSO
Kossin, Camargo & Sitkowski, J. Climate 2010
Typhoons and ENSO
Monthly Weather Review 1985 La Niña
5
4
3.5
Mean ACE per Year − TC categories
x 10
La Nina Neutral El Nino
3
ACE (m/s)
2
2.5
2
1.5
1
0.5
0
Chia & Ropelewski, J. Climate (2002)
El Niño
TS
TY1
TY2
TY3
TY4
TY5
Camargo & Sobel, J. Climate (2005).
Typhoons and ENSO
Camargo et al., part I & part II, J. Climate, 2007
Eastern North Pacific Hurricanes & ENSO ENSO
MJO
CLIMO
Camargo et al. , GGG (2008)
Models: ENSO & TC relationship
Zhao et al. MWR 2009
Vecchi & Villarini Science 2014
Wang et al. , J. Climate, 2014
Scientific Challenge: ENSO forecasts •
BAMS, 2012:
•
Skill of dynamical models improved during spring barrier.
•
Improved skill: most advanced, high‐resolution, fully coupled atmospheric‐ocean models with sophisticated data assimilation schemes and large ensembles.
•
Further skill improvement possible with improvements in dynamical models.
•
Higher skill of ENSO forecasts using multi‐model approach, even in spring – Tippett and Barnston (2008); Tippett et al. (2012)
Other modes of variability: Atlantic Meridional Mode ‐ AMM Kossin & Vimont, BAMS 2007
Kossin, Camargo & Sitkowski, J. Climate 2010
AMM & ENSO
Patricola et al., J. Climate 2014
AMM predictability/prediction • Well known relationship between ENSO & AMM • Vimont, J. Climate (2012): – Enhanced AMM predictability during boreal spring & long‐lead forecasts (depending on lead time) – Predictability related ENSO & high‐latitude Atlantic SST
What about the Quasi‐Biennial Oscillation (QBO)? North Atlantic:
Camargo & Sobel, J. Climate 2010
QBO – Western North Pacific
Monthly Weather Review, 1995
Ho et al. GRL, 2009 Camargo & Sobel, 2010
Let’s not forget the NAO ‐ North Atlantic Oscillation:
Kossin, Camargo & Sitkowski, J. Climate 2010
Predictability of the NAO • Until recently – no NAO predictability • Predictability of the winter NAO (Scaife et al. 2014) : – ENSO teleconnections – North Atlantic Ocean temperatures – Artic sea‐ice – QBO
Atlantic: Decadal Variability – Atlantic Multi‐decadal Oscillation (AMO)
Goldenberg et al., Science, 2001
Controversial topic: • Mann & Emanuel 2006: role of aerosols in Atlantic 70s‐ 80s cooling.
Role of aerosols, natural variability, GHG
Ting, Camargo, Li, Kushnir, submitted.
Multi‐year forecasts of Atlantic TC activity
Smith et al., Nature Geos. 2010
Vecchi et al., J. Climate, 2013 Caron et al., Clim. Dyn., 2014
Western North Pacific TC Decadal Variability Pacific Decadal Oscillation (PDO)
Chan 2008
ENSO decadal variability + PDO
Future Challenges • Improvement of simulations of climate modes in coupled models • Improvement in forecasting (ENSO, MJO, AMM, NAO) • Better understanding TC modulation by climate modes and their combined effects • Relationship among modes • Climate Change influence on climate modes and their teleconnections
Example 1: MJO & ENSO • Role of MJO in initiating and terminating ENSO (McPhaden et al. 2006, Hendon et al. 2007) • Nonlinearity of the combined MJO/ENSO impacts (Roundy et al. 2010) • Disruptions of ENSO teleconnections by the MJO (Hoell et al. GRL, 2014)
Example 2: TC size & ENSO
Camargo & Knaff, in preparation