An Analysis of Tropical Ocean Diurnal Warm Layers

Abstract During periods of light surface wind, a warm stable layer forms at the ocean surface with a maximum sea surface temperature (SST) in the early afternoon. The diurnal SST amplitude (DSA) associated with these diurnal warm layers (DWLs) can reach several degrees and impact the tropical climate variability. This paper first presents an approach to building a daily time series of the DSA over the tropics between 1979 and 2002. The DSA is computed over 2.5° of latitude–longitude regions using a simple DWL model forced by hourly-interpolated surface radiative and turbulent fluxes given by the 40-yr ECMWF Re-Analysis (ERA-40). One advantage of this approach is the homogeneity of the results given by the relative homogeneity of ERA-40. The approach is validated at the global scale using empirical DWL models reported in the literature and the Surface Velocity Program (SVP) drifters of the Marine Environmental Data Service (MEDS). For the SVP dataset, a new technique is introduced to derive the diurnal var...

[1]  W. Large,et al.  Oceanic vertical mixing: a review and a model with a nonlocal boundary layer parameterization , 1994 .

[2]  Robert Pinkel,et al.  Diurnal cycling: observations and models of the upper-ocean response to diurnal heating, cooling, and wind mixing. Technical report , 1986 .

[3]  M. Balmaseda,et al.  The role of the ocean in the Madden–Julian Oscillation: Implications for MJO prediction , 2007 .

[4]  G. Mellor,et al.  Development of a turbulence closure model for geophysical fluid problems , 1982 .

[5]  T. Shinoda.  Impact of the Diurnal Cycle of Solar Radiation on Intraseasonal SST Variability in the Western Equatorial Pacific , 2005 .

[6]  J. S. Godfrey,et al.  A diagnostic model of the diurnal cycle of sea surface temperature for use in coupled ocean‐atmosphere models , 2005 .

[7]  H. Kawamura,et al.  Study on a Platform Effect in the In Situ Sea Surface Temperature Observations under Weak Wind and Clear Sky Conditions Using Numerical Models , 2000 .

[8]  Carol Anne Clayson,et al.  Variability of Tropical Diurnal Sea Surface Temperature , 2007 .

[9]  Hiroshi Kawamura,et al.  Evaluation of the Diurnal Warming of Sea Surface Temperature Using Satellite-Derived Marine Meteorological Data , 2002 .

[10]  Peter J. Webster,et al.  Clouds, Radiation, and the Diurnal Cycle of Sea Surface Temperature in the Tropical Western Pacific , 1996 .

[11]  E. F. Bradley,et al.  Bulk Parameterization of Air–Sea Fluxes: Updates and Verification for the COARE Algorithm , 2003 .

[12]  X. Zeng,et al.  A prognostic scheme of sea surface skin temperature for modeling and data assimilation , 2005 .

[13]  Peter Cornillon,et al.  The distribution of diurnal sea surface warming events in the western Sargasso Sea , 1985 .

[14]  R. Lukas,et al.  Upper-Ocean Heat and Salt Balances in the Western Equatorial Pacific in Response to the Intraseasonal Oscillation during TOGA COARE* , 2000 .

[15]  Brett Candy,et al.  Parameterizations of the ocean skin effect and implications for satellite-based measurement of sea-surface temperature , 2003 .

[16]  E. F. Bradley,et al.  Cool‐skin and warm‐layer effects on sea surface temperature , 1996 .

[17]  Yoshimi Kawai,et al.  Diurnal sea surface temperature variation and its impact on the atmosphere and ocean: A review , 2007 .

[18]  P. M. Saunders,et al.  The Temperature at the Ocean-Air Interface , 1967 .

[19]  Peter J. Minnett,et al.  The Global Ocean Data Assimilation Experiment High-resolution Sea Surface Temperature Pilot Project , 2007 .

[20]  C. Donlon,et al.  Diurnal signals in satellite sea surface temperature measurements , 2003 .

[21]  Chelle Leigh Gentemann.  Diurnal warming at the ocean surface , 2007 .

[22]  Net Shortwave Fluxes over the Ocean , 1999 .

[23]  J. Kondo,et al.  On Wind-Driven Current and Temperature Profiles with Diurnal Period in the Oceanic Planetary Boundary Layer , 1979 .

[24]  Daniele Iudicone,et al.  Mixed layer depth over the global ocean: An examination of profile data and a profile-based climatology , 2004 .

[25]  J. Kennedy,et al.  A global climatology of the diurnal variations in sea‐surface temperature and implications for MSU temperature trends , 2007 .

[26]  Eric Guilyardi,et al.  Modeling Diurnal and Intraseasonal Variability of the Ocean Mixed Layer , 2005 .

[27]  J. Kennedy,et al.  Improved Analyses of Changes and Uncertainties in Sea Surface Temperature Measured In Situ since the Mid-Nineteenth Century: The HadSST2 Dataset , 2006 .

[28]  E. Guilyardi,et al.  Impact of resolving the diurnal cycle in an ocean–atmosphere GCM. Part 2: A diurnally coupled CGCM , 2007 .

[29]  P. Flament,et al.  Amplitude and Horizontal Structure of a Large Diurnal Sea Surface Warming Event during the Coastal Ocean Dynamics Experiment , 1994 .

[30]  Peter Cornillon,et al.  Large Diurnal Sea Surface Temperature Variability: Satellite and In Situ Measurements , 1986 .

[31]  B. Liebmann,et al.  Description of a complete (interpolated) outgoing longwave radiation dataset , 1996 .

[32]  J. Duvel,et al.  Indo-Pacific Sea Surface Temperature Perturbations Associated with Intraseasonal Oscillations of Tropical Convection , 2007 .

[33]  R. Lukas,et al.  Observation of large diurnal warming events in the near-surface layer of the western equatorial Pacific warm pool , 1997 .

[34]  J. Duvel,et al.  Intraseasonal Convective Perturbations Related to the Seasonal March of the Indo-Pacific Monsoons , 2007 .

[35]  Brian Ward,et al.  Near‐surface ocean temperature , 2006 .

[36]  Mei Zhao,et al.  Comparison of ERA40 and NCEP/DOE near‐surface data sets with other ISLSCP‐II data sets , 2006 .

[37]  A. Sterl,et al.  The ERA‐40 re‐analysis , 2005 .

[38]  Peter Challenor,et al.  A global study of diurnal warming using infrared satellite-derived sea surface temperature , 2003 .

[39]  M. Chou,et al.  Estimation and Model Validation of Surface Solar Radiation and Cloud Radiative Forcing Using TOGA COARE Measurements. , 1997 .

[40]  I. Robinson,et al.  A global study of diurnal warming using satellite-derived sea surface temperature , 2003 .

[41]  P. Poulain,et al.  Quality Control and Interpolations of WOCE-TOGA Drifter Data , 1996 .

[42]  D. Rudnick,et al.  The Dynamics of Double Monsoon Onsets , 2001 .

[43]  S. P. Anderson,et al.  Surface meteorology and air-sea fluxes in the western equatorial Pacific warm pool during the TOGA c , 1996 .

[44]  Thomas M. Smith,et al.  Improved Global Sea Surface Temperature Analyses Using Optimum Interpolation , 1994 .

[45]  M. Mcphaden,et al.  The upper ocean heat balance in the western equatorial Pacific warm pool during September–December 1992 , 1997 .

[46]  H. Hendon,et al.  Mixed Layer Modeling of Intraseasonal Variability in the Tropical Western Pacific and Indian Oceans , 1998 .