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PURPOSE ^

AIR_SEA: Introduction to the AIR_SEA TOOLBOX

SYNOPSIS ^

This is a script file.

DESCRIPTION ^

 AIR_SEA: Introduction to the AIR_SEA TOOLBOX

CROSS-REFERENCE INFORMATION ^

This function calls: This function is called by:

SOURCE CODE ^

0001 % AIR_SEA: Introduction to the AIR_SEA TOOLBOX
0002 
0003 %              AIR_SEA TOOLBOX (version 2.0: 8/9/99)
0004 %
0005 % 1) Introduction: Welcome to the AIR_SEA toolbox, a collection of MATLAB
0006 % programs (m-files) which can be used to compute surface wind stress and
0007 % heat flux components from buoy and shipboard atmospheric and near-surface
0008 % oceanographic time series measurements. All m-files include a header
0009 % which describes the mfile's function, input and output variables, and
0010 % key references when important. They have been written for use with
0011 % MATLAB 5.
0012 %
0013 % 2) Conventions:  While not required for many m-files, it is generally
0014 % assumed that the input time series of measured variables are hourly
0015 % averaged column or row vectors and the other input variables are scalars,
0016 % all expressed in MKS units. Two time conventions are used: a) decimal
0017 % Julian yearday where 0000 UT Jan 1 equals 0.0, and b) calender yearday
0018 % where Jan 1 equals 1. The choice of which convention is used is
0019 % internally consistent between m-files.
0020 %
0021 % 3) Programs used to compute heat flux components:
0022 %
0023 %    Shortwave flux:
0024 %
0025 %        SWHF: computes net sw flux into ocean and albedo. Uses
0026 %              SORADNA1 and ALBEDO to compute solar altitude, no-sky
0027 %              insolation and albedo.
0028 %
0029 %        SORADNA1: computes no-sky insolation and solar altitude at
0030 %              a given time and location.
0031 %
0032 %        ALBEDO: computes ocean albedo following Payne (1972).
0033 %
0034 %    Longwave flux:
0035 %
0036 %        LWHF: computes net lw flux into ocean when downward
0037 %              lw radiation is measured, using Dickey et al (1994).
0038 %
0039 %        BLWHF: computes net lw flux into the ocean when downward
0040 %              lw radiation is NOT measured. Uses SATVAP. Requires
0041 %              as input a cloudiness correction factor from CLOUDCOR.
0042 %
0043 %        CLOUDCOR: cloudiness correction factor used in bulk formulae,
0044 %              based on estimated Cloud Fraction, which is either observed
0045 %              directly or estimated, using, e.g., REEDCF.
0046 %
0047 %        REEDCF: computes daily average Cloud Fraction using formula of
0048 %              Reed (1977), who relates daily average cloudiness to the observed
0049 %              reduction in solar insolation from clear-sky values.
0050 %
0051 %    Sensible and latent fluxes:
0052 %
0053 %        HFBULKTC: uses a simplified version of Fairall et al (1996)
0054 %              TOGA/COARE code to compute sensible and latent heat
0055 %              fluxes into ocean. Present version includes a) Rogers'
0056 %              weighting factor for unstable conditions, b) the effects
0057 %              of gustiness, c) a constant marine boundary layer height,
0058 %              d) a limit of zr/L <=3.0 to ensure that the code converges
0059 %              to nonzero stress and heat flux values for strongly stable
0060 %              conditions, e) cool-skin effect, and f) Webb correction for
0061 %              latent heat flux.  NOTE: both cool-skin and Webb correction
0062 %              are optional, and user must decide if they want these used,
0063 %              e.g., in SLHFTC. Warm layer effects are not included in this
0064 %              version.  Uses VISCAIR and QSAT to compute air viscosity
0065 %              and saturation specific humidity, CDNTC the neutral drag
0066 %              coefficient, and PSIUTC and PSITTC to adjust the different
0067 %              transfer coefficients to the measurement heights for a
0068 %              given stability. Also returns related variables.
0069 %
0070 %        SLHFTC: includes ocean surface current and HFBULKTC to comput
0071 %              sensible and latent heat fluxes into ocean.
0072 %
0073 %        RAIN_FLUX: computes heat flux and momentum flux due to rain.
0074 %
0075 % 4) Programs relating wind speed, height, and surface stress.
0076 %
0077 %    Neutral conditions:
0078 %
0079 %        CDNLP: computes neutral Cd, 10m wind following Large and Pond (1981).
0080 %        CDNTC: computes neutral Cd, 10m wind following Smith (1988).
0081 %        CDNVE: computes neutral Cd, 10m wind following Vera (1983).
0082 %
0083 %        STRESSLP: computes the neutral wind stress using Large and Pond.
0084 %        STRESSTC: computes the neutral wind stress following Smith.
0085 %        STRESSVE: computes the neutral wind stress using Vera.
0086 %
0087 %        SPSHFTLP: computes winds at another height using Large&Pond drag.
0088 %        SPSHFTTC: computes winds at another height using Smith drag.
0089 %        SPSHFTVE: computes winds at another height using Vera drag.
0090 %
0091 %    Non-neutral conditions:
0092 %
0093 %        HFBULKTC: uses simplified version of Fairall et al (1996)
0094 %              TOGA/COARE code to compute surface wind stress amplitude,
0095 %              (Uses Monin-Obukov similarity theory with surface rougness using
0096 %              Charnock approach, like Smith (1988)).
0097 %
0098 %        SLHFTC: includes ocean surface current and HFBULKTC to
0099 %              compute surface wind stress vector as well as scalar parameters.
0100 %
0101 % 5) Programs used to estimate wave effects on the measured wind speed:
0102 %
0103 %        WAVEDIST: estimate true wind speed at 10-m height.
0104 %        WAVEDIS1: estimate true wind speed at measurement height.
0105 %        WAVEDIS2: plots wave effects at measurement height vs. wave height.
0106 %        OMEGALMC: estimates wave effect on wind log profile.
0107 %        CDNVE: computes neutral drag coefficient following Vera (1983).
0108 %
0109 %        See WDNOTES for additional information.
0110 %
0111 % 6) Other useful programs:
0112 %
0113 %        AS_CONSTS: contains various constants used in the toolbox.
0114 %
0115 %        DAVEALB: computes daily mean albedo.
0116 %        SUNRISE: computes GMT time of sunrise and sunset (uses SORADNA1).
0117 %
0118 %        GREG2: converts decimal yearday into Julian calendar day.
0119 %        JULIANMD: converts Gregorian calendar dates to decimal Julian day
0120 %                  for days beginning at midnight UT
0121 %        YEARDAY: converts calender month and day into yearday.
0122 %
0123 %        DELQ: air-sea specific humidity difference.
0124 %        EP: net precipitation and evaporation accumulation.
0125 %        QSAT: saturation specific humidity.
0126 %        RELHUMID: relative humidity from wet/dry bulb thermometers.
0127 %        RHADJ: adjusts RH for values above 100.
0128 %        SATVAP: saturation vapour pressure.
0129 %        VAPOR: heat of evaporation.
0130 %        VISCAIR: viscosity of air at a given temperature.
0131 %        COOL_SKIN: computes cool-skin parameters.
0132 %        T_HFBULKTC: tests HFBULKTC with COARE data.
0133 %
0134 % 7) See CONTENTS for listing of all m-files in this toolbox.
0135 %
0136 % 8) History:
0137 %
0138 %    Version 1.0:
0139 %
0140 %    The initial assembly of this toolbox was a collaborative effort
0141 %    by Bob Beardsley (WHOI), Ed Dever (SIO), Steve Lentz (WHOI), Jim
0142 %    Edson (WHOI), and Dick Payne (WHOI), with additional input from
0143 %    Steve Anderson (WHOI), Jay Austin (WHOI), Chris Fairall (NOAA),
0144 %    Carl Friehe (UCI), Bill Large (NCAR), Dave Rogers (SIO), Rich
0145 %    Signell (USGS), and Bob Weller (WHOI). Their input was very useful.
0146 %
0147 %    Version 1.1:
0148 %
0149 %    Rich Pawlowicz (UBC) then converted the original version 1.0
0150 %    (written for MATLAB 4) into a much improved version 1.1 (optimized
0151 %    for MATLAB 5) which included major coding improvements, the addition
0152 %    of some new m-files, and some corrections of existing m-files.
0153 %
0154 %    Version 1.2:
0155 %
0156 %    Ayal Anis (U. Dalhousie) then modified HFBULKTC to include the
0157 %    Fairall et al (1996) cool-skin effect and Webb correction to the
0158 %    latent heat flux, plus added files to test the code with COARE
0159 %    data. Ayal and R. Onken (NATO) also contributed several other files.
0160 %
0161 %    Version 2.0:
0162 %
0163 %    Bob Beardsley has added several m-files and made simple changes
0164 %    to the various m-files to standardize the format and documentation.
0165 %
0166 % 9) Comments, Suggestions, and Improvements
0167 %
0168 %    Please contact Bob Beardsley at rbeardsley@whoi.edu with questions
0169 %    and comments, especially concerning bugs (and their possible fixes),
0170 %    ideas for additional m-files, plus any m-files which you want to
0171 %    contribute to this toolbox. Your help in improving this toolbox will
0172 %    be greatly appreciated.
0173 %
0174 %    As new or/or improved m-files are developed for this toolbox, they
0175 %    will be added to the AIR_SEA toolbox folder located at the SEA-MAT
0176 %    Web site (crusty.usgs.gov/sea-mat/).  SEA-MAT is a collection of
0177 %    MATLAB mfiles for the display and analysis of oceanographic data.
0178 %
0179 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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