Climate variability in the Atlantic Dissertation Proposal Jiande Wang

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Climate variability in the AtlanticDissertation
ProposalJiande Wang

• My background
• Identification of the problem
• Objectives hypotheses
• Proposed activities
• Timetable

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My background

• 08/1984-06/1991 MS Nanjing Inst.of Meteorology
  (NIM)
• 06/1991-06/1997 Teaching undergraduate
  meteorology at NIM
• 08/1997-present UMD graduate study
• 05/1999 MS awarded

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Publications

• Wang, J., and T. Dongshen, 1993 Feature and
  driving mechanism of mid-low latitude
  low-frequency oscillation in summer. Journal of
  Nanjing Inst. of Meteorology. Vol.16, No.4,
  521-526.
• Wang, J., and T. Dongshen, 1993 Low-frequency
  oscillation and mechanism of vertical circulation
  of eastern Asian summer monsoon. ACTA
  Meteorological Sinica. Vol.7, No.2, 280-285.
• Wang, J., and T. Dongshen, 1994 The influence of
  convective activities over south China sea on the
  northern hemisphere mid-low latitude atmosphere
  and its possible mechanism. Tropical Meteorology.
  Vol.10, No.2, 350-357.
• Tang, D., and W. Jiande, 1994 Relation of
  southern China precipitation to large scale water
  transporting flow and atmospheric heating field.
  Journal of Nanjing Inst. of Meteorology. Vol.17,
  No.2, 356-362.
• Zhu, Q., and W. Jiande, 1994 Three-dimensional
  vertical circulation low-frequency oscillation
  feature of eastern Asian winter monsoon. Journal
  of Nanjing Inst. of Meteorology. Vol.17, No.3,
  686-695.
• Wang, J., and T. Dongshen, 1994 The relationship
  between winter monsoon circulation and
  atmospheric heating field of eastern Asia.
  Scientia Meteorological Sinica, Vol.14, No.2 ,
  331-336.
• Wang, J., and T. Dongshen, 1996 Comparative
  study of diabatic heating in anomalous plum-rain
  year. Journal of Nanjing Inst. of Meteorology.
  Vol.19 No.2, 356-362.

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Importance of climate variability

• Flooding in Venezuela when
• Connection to SST anomalies where?

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Previous research

• Observational evidence of correlation Hastenrath
  and Heller, 1977 Lamb, 1978 Chu and Hastenrath,
  1981 Moura and Shukla, 1981 Folland, 1986
  Wagner and da Silva, 1993 Enfield, 1996
• Existence of coupled modes Merle, 1980 Zebiak,
  1993 Carton and Huang, 1994 Hastenrath and
  Greischar, 1993 Carton et al., 1996 Houghton et
  al., 1992 Ruiz-Barradas, et al. (2000)
• Failure of simple models Chung, Carton, and Nigam
  (2000)
• Calculating heat transport Jung, 1952 Oort,
  1976 Lamb, 1982 Hsiung, 1989 Bryden, 1991
  Wang and Carton, 2000

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Scientific Objectivesexpressed as questions

• Convection and longwave radiation play key roles
  in driving the tropical atmosphere. What role
  does convection and longwave radiation play in
  modulating the atmospheric response to local,
  and remote SST?
• Both heat transport and atmospheric climate are
  connected to changes in SST. How are the two
  processes connected together?
• Show the relationship at interannual timescales

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Proposed activities

• Examination of AMIP-II AGCMs and possibly other
  AGCM runs to discern the response of the
  atmosphere to anomalous SST
• Examination of Atlantic Ocean heat transport as
  represented in oceanic reanalyses

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Examination of the response of the atmosphere to
anomalous SST

• Need to examine multiple AGCMs
• Model-dependence
• Statistical approach advantages/disadvantages
• REOF
• Examination of events advantages/disadvantages
• Implications for predictability
• Ensemble mean and variance

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Results from two simulationsmy results

• Models
• NCAR CCM3.5 T42L18
• UKMO HADAM3 (3.752.519L)
• Comparison
• Seasonal cycle
• Atlantic Nino mode
• Interhemispheric mode

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Seasonal cycle
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Atlantic Nino
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Interhemispheric mode
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Examination of the response of the ocean to
anomalous winds and heating (the heat transport
problem)my results

• Climatological seasonal heat storage and
  transport divergence a comparison
• Interannual variability of heat transport not
  shown

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Climatological seasonal heat transport
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Timetable

• Examine of AMIP II AGCM output
• 6 months
• Examine the predictability of variability
• 3 months
• Examine the relationship between HT and climate
  modes
• 3 months
• Write up the results
• 6 months
• Total time 18 months