Convection process in the north pacific from argo data
This presentation is the property of its rightful owner.
Sponsored Links
1 / 29

Convection process in the North Pacific from ARGO data PowerPoint PPT Presentation


  • 61 Views
  • Uploaded on
  • Presentation posted in: General

Convection process in the North Pacific from ARGO data. 1 Eunjeong Lee, Yign Noh, 2 Bo Qiu 1 Department of atmospheric sciences, Yonsei University 2 Department of Oceanography, University of Hawaii. Department of Atmospheric Sciences, Yonsei University. Contents. Objective About ARGO

Download Presentation

Convection process in the North Pacific from ARGO data

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Convection process in the north pacific from argo data

Convection process in the North Pacific from ARGO data

1Eunjeong Lee, Yign Noh, 2Bo Qiu

1Departmentof atmospheric sciences, Yonsei University

2Department of Oceanography, University of Hawaii

Department of Atmospheric Sciences, Yonsei University


Contents

Contents

  • Objective

  • About ARGO

  • Data analysis

    - ARGO

    - NCEP/NCAR reanalysis I

  • Results

    PartⅠ - Response of the ocean to the surface cooling

    - Deepening of MLD

    - In the KE region (Eddy process)

    PartⅡ - Correlation

    - Efficiency (deepening, heating & cooling)

  • Conclusion

Department of Atmospheric Sciences, Yonsei University


Objective

Objective

  • Analysis of the convection process in the upper ocean to the

    atmospheric forcing using ARGO data

    • How are the variations of the MLD and SST related to the surface

      forcing?

       i) Understanding the air-sea interaction in the North Pacific

      ii) Providing the information for the parameterization of

      convection in the mixed layer model

Department of Atmospheric Sciences, Yonsei University


About argo

About ARGO

  • Processing

  • Position of float

  • Profile data, metadata, trajectories and technical data

  • An ascending profile with measurements

    (e.g. pressure, temperature, salinity)

  • Data mode (e.g. R : Real time, D : Delayed mode, A : adjusted values)

  • Quality control (e.g. 1:good data, 4:bed data, 9:missing value)

Department of Atmospheric Sciences, Yonsei University


Data analysis argo

Data analysis : ARGO

  • 27 different locations

  • Area : North Pacific

    (130-240˚E, 20-60˚N)

    • 0-500m depth

  • Period : 2001 - 2007

  • Data processing

    • - use data with quality control 1 or 2.

    • - semi-monthly averaging

    • - mixed layer depth : z = z [T(0)-0.5]

Department of Atmospheric Sciences, Yonsei University


Convection process in the north pacific from argo data

Data analysis : NCEP data

  • NCEP reanlaysis I – surface heat flux, SST

  • Surface heat flux

  • (+) : direction from atmosphere to ocean

  • Data processing

    • semi-monthly averaging

    • 2001-2007 data on an average compare with each year value

  • Department of Atmospheric Sciences, Yonsei University


    Part response of the ocean to the surface cooling

    Location

    Mean

    Each year

    Heat Flux

    SST

    MLD

    Part Ⅰ : Response of the ocean to the surface cooling

    • 150-155˚E, 28-30˚N

    • 135-140˚E, 28-30˚N

    2005-2006년

    2005-2006년

    Reduce

    Department of Atmospheric Sciences, Yonsei University


    Part deepening of mld in winter

    slower deepening

    faster deepening

    Part Ⅰ : Deepening of MLD in winter

    135-140˚E, 28-30˚N

    Location

    2004-2005년

    2005-2006년

    Heat Flux

    SST

    MLD

    Department of Atmospheric Sciences, Yonsei University


    Part deepening of mld in winter1

    Insensitive to

    surface heat flux

    Part Ⅰ :Deepening of MLD in winter

    175-180˚W, 42-44˚N

    Location

    2003-2004년

    2002-2003년

    Heat Flux

    SST

    MLD

    Department of Atmospheric Sciences, Yonsei University


    The ke region

    The KE region

    • Near 145˚E, 35˚N

    • High T & S (20°, 34.5‰), 50~300m/s velocity

    • Eddy process

    Department of Atmospheric Sciences, Yonsei University


    Convection process in the north pacific from argo data

    The KE region

    PDO index

    EKE level

    [Qiu et al.(2008)]

    • Center of action of wind forcing is in the eastern half of the N Pacific basin

    • Positive (negative) phase of PDO generates – (+) local SSH through Ekman divergence (convergence)

    Department of Atmospheric Sciences, Yonsei University


    Part eddy process

    Part Ⅰ :Eddy process

    145-150˚E, 32-34˚N

    Location

    2004-2005년

    2005-2006년

    Heat Flux

    SST

    MLD

    Department of Atmospheric Sciences, Yonsei University


    Part eddy process1

    Part Ⅰ :Eddy process

    Kuroshio Extension

    • 155-160˚E, 32-34˚N

    2005-2006년

    Location

    the effect of internal ocean dynamics is important

    → eddy process

    Due to eddy

    processing

    MLD

    Eddy processing

    interrupt

    MLD deepening

    Department of Atmospheric Sciences, Yonsei University


    Part relation

    No horizontal advection

    Part Ⅱ :Relation

    d(MLD)=MLD(t+15)-MLD(t)

    • 130-135˚W, 50-52˚N

    d(MLD)&Qdt

    d(SST)&Qdt

    SST&MLD

    Department of Atmospheric Sciences, Yonsei University


    Part relation1

    Part Ⅱ :Relation

    • 155-160˚E, 32-34˚N

    d(MLD)&Qdt

    SST&MLD

    d(SST)&Qdt

    horizontal advection

    Department of Atmospheric Sciences, Yonsei University


    Part correlation

    -0.1

    -0.05

    -0.6

    -0.5

    -0.4

    -0.3

    -0.2

    0.05

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    -0.8

    0

    0.8

    Part Ⅱ : Correlation

    summer

    • d(MLD) & Qdt

    MAY & JUN

    JUL & AUG

    d(SST)Qdt

    • Strong heating→strong stratification

    • → shallower MLD

    • Weak correlation in the KE region duo to advection effect

    • Already shallow MLD

    • → no longer weakening of MLD

    Department of Atmospheric Sciences, Yonsei University


    Part correlation1

    -0.1

    -0.05

    -0.6

    -0.5

    -0.4

    -0.3

    -0.2

    0.05

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    -0.8

    0

    0.8

    Part Ⅱ : Correlation

    Earlysummer

    • d(MLD) & Qdt

    Weak eddy

    Strong eddy

    Department of Atmospheric Sciences, Yonsei University


    Part correlation2

    -0.1

    -0.05

    -0.6

    -0.5

    -0.4

    -0.3

    -0.2

    0.05

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    -0.8

    0

    0.8

    Part Ⅱ : Correlation

    winter

    • d(MLD) & Qdt

    NOV & DEC

    JAN & FEB

    d(SST)Qdt

    • Strong cooling →weak stratification

    • → rapid convective deepening

    • Weak correlation in the KE region duo to advection effect

    • Already deep MLD

    • → no longer deepening of MLD

    • : Maximum MLD is insensitive to surface cooling

    Department of Atmospheric Sciences, Yonsei University


    Part correlation3

    -0.1

    -0.05

    -0.6

    -0.5

    -0.4

    -0.3

    -0.2

    0.05

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6

    -0.8

    0

    0.8

    Part Ⅱ : Correlation

    Early winter

    • d(MLD) & Qdt

    Weak eddy

    Strong eddy

    Department of Atmospheric Sciences, Yonsei University


    Part deepening efficiency

    Part Ⅱ : Deepening efficiency

    • Deepening efficiency

    Department of Atmospheric Sciences, Yonsei University


    Part deepening efficiency1

    • Stronger efficiency than NOV& DEC except KE region

    -0.02

    -0.01

    -0.005

    -0.004

    -0.001

    0

    0.001

    11

    0.003

    12

    0.004

    0.005

    0.007

    0.01

    0.02

    -0.007

    -0.003

    -0.002

    0.002

    Part Ⅱ : Deepening efficiency

    winter

    • Deepening efficiency

    NOV & DEC

    JAN & FEB

    • Overall positive efficiency

    • Negative efficiency in the KE region

    Department of Atmospheric Sciences, Yonsei University


    Part heating cooling efficiency

    Part Ⅱ : Heating(Cooling) efficiency

    • Heating(Cooling) efficiency

    Department of Atmospheric Sciences, Yonsei University


    Part heating cooling efficiency1

    -0.02

    -0.01

    -0.005

    -0.004

    -0.001

    0

    0.001

    11

    0.003

    12

    0.004

    0.005

    0.007

    0.01

    0.02

    -0.007

    -0.003

    -0.002

    0.002

    Part Ⅱ : Heating(Cooling) efficiency

    summer

    • Heating efficiency

    MAY & JUN

    JUL & AUG

    Advection + heating effect

    Low heating efficiency

    Department of Atmospheric Sciences, Yonsei University


    Part heating cooling efficiency2

    Advection + heating effect

    Advection + cooling effect

    -0.02

    -0.01

    -0.005

    -0.004

    -0.001

    0

    0.001

    11

    0.003

    12

    0.004

    0.005

    0.007

    0.01

    0.02

    -0.007

    -0.003

    -0.002

    0.002

    Part Ⅱ : Heating(Cooling) efficiency

    winter

    • Cooling efficiency

    NOV & DEC

    JAN & FEB

    Low cooling efficiency

    Department of Atmospheric Sciences, Yonsei University


    Conclusion

    Conclusion

    • The response of the ocean mixed layer and sea surface temperature to surface forcing in the Pacific was investigated by analyzing ARGO data.

    • The d(SST) and d(MLD) has high correlation and efficiency with surface cooling except in the KE region in early summer and winter.

    • The d(MLD) are more sensitive to the surface heat flux in late summer and winter.

    • The initial convective deepening shows large variability, but the maximum MLD does not show much variability.

    • In the KE region,

    • - the MLD increase is interrupted by mesoscale eddies

    • - the heat transport by the Kuroshio is important to determine SST

    Department of Atmospheric Sciences, Yonsei University


    Convection process in the north pacific from argo data

    Reference

    • Argo Data Management Team (2004), Argo quality control manual, version 2.0b, p. 23, Argo Data Manage., Toulouse, France.

    • Kalnay, E., M. Kanamitsu, R. Kistler, W. Collins, D. Deaven, L. Gandin, M. Iredell, S. Saha, G. White, J. Woollen, Y. Zhu, M. Chelliah, W. Ebisuzaki, W. Higgins, J. Janowiak, K. C. Mo, C. Ropelewski, J. Wang, A. Leetmaa, R. Reynolds, R. Jenne, and D. Joseph (1996), The NCEP/NCAR 40-Year Reanalysis Project, Bull. Am. Meteorol. Soc., 77, 437- 471.

    • Qiu, B., S. Chen, and P. Hacker (2007), Effect of mesoscale eddies on Subtropical Mode Water variability from the Kuroshio Extension System Study (KESS), J. Phys. Oceanogr., 37, 982-1000.

    Department of Atmospheric Sciences, Yonsei University


    Thank you

    Thank you

    Department of Atmospheric Sciences, Yonsei University


    Convection process in the north pacific from argo data

    (a) Upstream KE path length (141-153°E)

    (b) Eddy kinetic energy (141-153°E, 32-38°N)

    Stable yrs: 1993-94, 2002-04

    Unstable yrs: 1996-2001, 2006-07


  • Login