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Pacific Decadal Variability (PDV) and teleconnections to Pan American climate

Pacific Decadal Variability (PDV) and teleconnections to Pan American climate. Nate Mantua JISAO/SMA Climate Impacts Group University of Washington. November-April SLP change: (1977-88) - (1965-76).

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Pacific Decadal Variability (PDV) and teleconnections to Pan American climate

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  1. Pacific Decadal Variability (PDV) and teleconnections to Pan American climate Nate Mantua JISAO/SMA Climate Impacts Group University of Washington

  2. November-April SLP change: (1977-88) - (1965-76)

  3. Cool season Aleutian Low variability: (Nitta and Yamada 1989, J. Met. Soc. Japan; Trenberth 1990, BAMS) North Pacific winter sea level pressure field (i.e. the Aleutian Low) “shifted” in 1977

  4. The Pacific Decadal Oscillation • an El Niño-like pattern of climate variability • 20 to 30 year periods of persistence in North American and Pacific Basin climate • warm extremes prevailed from 1925-46, and again from 1977-98; a prologed cold era spanned 1947-76 1925 1947 1977 1998? (Mantua, Hare, Zhang, Wallace and Francis 1997, BAMS)

  5. 7yr Low-pass versus high-pass filtered leading EOFs of Global SST(Higgins et al. 2000, J. Climate)

  6. 200mb streamfunction regressed on HP and LP SST indices(Higgins et al. 2000)

  7. Warm phase PDO and North American climate temperature precipitation Todd Mitchell, UW/JISAO

  8. Interhemispheric teleconnections to precip., streamflow, and temperature (Oct-Sept)(Dettinger et al. 2001 in Markgraf (Ed.))

  9. Some key unanswered questions • How many decadal/interdecadal modes are there in Pacific climate? • What are their dynamics and predictability? • Can we detect phase changes soon after they take place? • Teleconnections to the Americas • What are the spatial/seasonal patterns • What are the roles for land-surface feedbacks? • Interactions with other modes • Do patterns of PDV modulate ENSO teleconnections?

  10. Distinct modes of NP SST variability?from a Rotated PC analysis of COADS SST 1945-1993(Nigam et al. 1999, Eos Trans.)

  11. NP SST regressions onto JJA PDSI and riverflow(Nigam et al. 1999, Eos Trans.)

  12. Early-Late AZNM monsoon composites(Higgins and Shi 2000)

  13. Spring Snowpack and summer NM rainfall(Gutzler 2000, J. Climate) Solid dots: 1961-1990 Open circles: 1951-60, 1991-95

  14. ENSO/PDO composite winter precipitation anomaliesEvidence for “constructive and destructive interference”?(Gershunov, Barnett and Cayan, 1999 Eos)

  15. ENSO, SW DJFM precip, pre and post 1977(Gutzler et al 2002, Weather and Forecasting) DRY WET 1950-1976 1977-1997

  16. SST variations July 2003 SST anomalies

  17. PDV projects: revised outline INTRODUCTION: motivation II. the nature of PDV Instrumental Description of PDV Paleo-reconstructions of PDV III. PDV modeling, mechanisms and predictability PDV observing strategy: past and future mechanisms of PDV in coupled models Prediction and predictability of PDV PDV and land surface feedbacks PDV and global warming IV. PDV impacts: mechanisms and predicting impacts Fisheries/Marine food webs water resources Energy, fire, Human health, Ag?

  18. Feb 2003 PDV workshop • A small two day workshop organized by Ed Sarachik, Nate Mantua, and David Legler to discuss and revise a draft prospectus for a PDV science program http://www.usclivar.org/PDV_0203.html And ftp://ftp.atmos.washington.edu/mantua/PDV

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