Journal of Environmental Science International (한국환경과학회지)

The Korean Environmental Sciences Society (한국환경과학회)
권호 표지

Objective Estimation of Velocity Streamfunction Field with Discretely Sampled Oceanic Data 1: with Application of Helmholtz Theorem

객관적 해석을 통한 속도 유선함수(streamfunction) 산출 1: 헬름홀쯔(Helmholtz) 정리의 응용

  • 조황우 (부경대학교 해양산업개발연구소)
  • Published : 1997.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

An objective method for the generation of velocity streamfunction is presented for dealing with discretely sampled oceauc data. The method treats a Poisson equation (forced by vorticity) derived from Helmholtz theorem In which streamfunction is obtained by isolating the non-divergent part of the two-dimensional flow field. With a mixed boundary condition and vorticity field estimated from observed field, the method Is Implemented over the Texas-Louisiana show based on the current meter data of the Texas-Louisiana Shelf Circulation and Transport Processes Study (LATEX) measured at 31 moorings for 32 months (April 1992 - November 1994). The resulting streamfunction pattern is quote consistent with observations. The streamfunction field by this method presents an opportunity to initiauze and to verier computer models for local forecasts of enoronmental flow conditions for ell spill, nutrient and plankton transports as well as opportuuty to understand shelf-wlde low-frequency currents.

본 연구는 해양에서 비규칙적으로 관측된 유속자료를 이용 속도유선함수를 객관적해석을 통하여 산출하였다. 이를 위하여 헬름흘쯔(Helmholtz)정리를 응용 2차원 유속장의 비발산 부분만 나타내는 유선함수와 와도와의 관계를 규정하는 포이송(Poisson)방정식을 도출하고, 혼합경계조건과 관측치로부터 산출된 와도장을 이용 유선함수를 구하였다. 위의 방법을 실현하기 위하여 텍사스-루이지아나 대륙붕 순환 및 수송 연구(LATEX측 일환으로 텍사스-루이지아나 대륙붕의 31개 정점에서 32개월(1992년 4월 SIM 1994년 11월)간 관측된 해류계자료를 이용하였다. 본 방법으로 산출된 텍사스-루이지아나 대륙붕의 속도유선함수는 관측치와 잘 일치하였다. 본 연구에서 산출된 유선함수는 특정 해역의 저주파 운동의 이해뿐만 아니라 기름유출, 영양염 및 플랑크톤 수송과 관련한 환경유동모델의 초기화 및 검증에 응용될 것으로 기대된다.

Keywords

References

  1. Deep-Sea Res. v.23 A technique for objective analysis and design of oceanographic experiments applied to MODE-73 Bretherton, F. P.;R. E. Davis;C. B. Fandry
  2. J. Atmos. Oceanic Technol. v.4 Analysis models for the estimation of oceanic fields Carter, E. F.;A. R. Robinson
  3. J. Geophys. Res. Near-inertial oscillations over the Texas-Louisiana shelf Chen, C.;R. O. Reid;W. D. Nowlin
  4. J. Kor. Environ. Sci. Soc. Objective estimation of velocity streamfunction field with discretely sampled oceanic data II: with application of least-square regression analysis Cho, K.
  5. J. Geophys. Res. v.91 Low-frequency circulation on the Texas-Louisiana continental shelf Cochrane, J. D.;F. J. Kelly
  6. Comp. & Maths. with Appls. v.8 Smooth interpolation of scattered data by local thin plate splines Franke, R.
  7. Atmospheric-Ocean Dynamics Gill, A. E.
  8. Proc. IEEE v.66 On the use of windows for harmonic analysis with the discrete Fourier transform Harris, F. J.
  9. Mon. Wea. Rev. v.93 On the computation of stream-functions from the wind field Hawkins, H. F.;S. L. Rosenthal
  10. Objective analysis of ocean surface currents, Contributions on the Physical Oceanography of the Gulf of Mexico Hubertz, J. M.;A. W. Garcia;R. O. Reid
  11. Year, Annual Report, Mineral Management Service Texas-Louisiana shelf circulation and transport processes study Jochens, A. E.;W. D. Nowlin, Jr.
  12. J. Geophys. Res. Spatial scale analysis of hydrographic data over the Texas-Louisiana continental shelf Li, Y.;W. D. Nowlin, Jr.;R. O. Reid
  13. An introduction to optimal estimation Liebelt, P. B.
  14. Technical Proposal. Texas A&M University, Reference No. 93-06-T Louisiana/Texas Physical Oceanography Program Task A Nowlin, W. D. Jr.;A. E. Jochens;N. L. Guinasso Jr.;D. A. Wisenburg;R. O. Reid;S. A. Hsu;R. C. Hamilton
  15. J. Geophys. Res. v.100 Eddy-and wind-forced shelf circulation Oey, L.-Y.
  16. Numerical recipes Press, W. H.;B. P. Flannery;S. A. Teukolsky;W. T. Vettering
  17. J. Mar. Res. v.3 Streamlines from a discrete vector field: with application to ocean currents Pritchard, D. W.
  18. J. Geophys. Res. v.98 The annual cycle of the western boundary current in the Gulf of Mexico Sturges, W.
  19. J. Atmos. Oceanic Technol. v.2 Sea surface topography estimation with infrared satellite imaginary Vastano, A. C.;R. O. Reid
  20. Rev. Geophys. Space Phy. v.18 On using satellite altimetry to determine the general circulation of the ocean with application to geoid improvement Wunsch, C.;E. M. Gasposchkin