Yday Decimal yearday (UTC) To convert to matlab time format use: yd0=datenum(datestr('01-Jan-2011 00:00:00'))-1; tmatlab=yday+yd0; Lat Latitude (deg) Lon Longitude (deg) SOG Speed over ground (m/s) COG Course over ground (deg) Heading Ship's heading (deg) Cspd Current speed (m/s) Cdir Current direction (deg) from U10 Wind speed (m/s) relative to earth adjusted to 10 m Wdir Wind direction (deg) from relative to earth Ur10 Wind speed (m/s) relative to water adjusted to 10 m WdirR Wind direction (deg) from relative to water Pair10 Pressure (mb) adjusted to 10 m RH10 Relative humidity(%) adjusted to 10 m T10 Temperature (C) adjusted to 10 m Tsea Near surface sea temperature (C) from Sea snake with warm layer correction SST Sea surface (skin) temperature (C) from Tsea minus cool skin Q10 Specific humidity (g/Kg) adjusted to 10 m Qsea Specific humidity (g/Kg) 'near' ocean surface from sea snake SSQ Sea surface specific humidity (g/Kg) from Qsea minus cool skin stress Surface stress (N/m2) measured relative to water shf Sensible heat flux (W/m2) lhf Latent heat flux (W/m2) rhf Sensible heat flux from rain (W/m2) Solarup Reflected solar (W/m2) estimated from Payne (1972) Solardn Measured downwelling solar (W/m2) IRup Upwelling IR (W/m2) computed from SST IRdn Measured downwelling IR (W/m2) E Evaporation rate (mm/hr) P Precipitation rate (mm/hr) Evap Accumulated evaporation for Leg (mm) Precip Accumulated precipitation for Leg (mm) Interped 1=data interpolated due to poor relative winds 0=no interpolation TseaTSG Sea temperature from the Thermosalinograph at 5 m depth (C) SalTSG Salinity from the Thermosalinograph at 5 m depth (PSU) T02 Temperature (C) adjusted to 2 m Q02 Specific humidity (g/Kg) adjusted to 2 m RH02 Relative humidity(%) adjusted to 2 m sigH Significant wave height (m) cp Phase speed of dominant waves (m/s) sigDir Direction of dominant wave (deg) - placeholder dSolar Measured diffuse radiation (W/m2) zenith Solar zenith angle (deg) Smax Solar radiation at surface with no atmosphere (W/m2) Sclr Modeled clear sky radiation at ocean surface (W/m2) 12/10/11 Notes: Fluxes are defined as negative downward and positive upwards. For example, the net heat flux is defined as: Qnet = Solarup+Solardn+IRup+IRdn+lhf+shf+rhf Qnet<0 is heating ocean The wind and current directions are in meteorological convention (i.e., direction from). Tair is taken from the calibrated PSD and UConn aspirated air temperature sensors on the bow mast. These were least affected by solar heating. Qair and Pair are computed the calibrated UConn RH/T/P sensors on the on the bow mast. Q is less sensitive to solar heating as long as the temperature and RH are measured simultaneously. RH is reconstructed from the Q, aspirated Tair and P measurements to remove the effects of solar heating. The sonic anemometers on the bow mast are used to measure the wind speed and direction. Relative wind speed is taken into consideration to minimize flow distortion. Tsea is primarily measured by the sea snake with a few values provide by the IR radiometer deployed by LDEO. SST is estimated after correction for cool skin and this accounts for the difference between Tsea and SST. Similar corrections are applied to SSQ from Qsea. Solardn is provided by the ship's pyranometer on the top of the forward mast. IRdn represents an average of the gyrostabilized PSD purgeometer on top of its van and the ship's purgeometer on the top of the forward mast. The ship's purgeometer was first corrected for the effects of solar heating. Solarup is taken from a commonly used parameterization for surface albedo of the ocean (Payne, 1972). IRup was derived from the SST measurements using the COARE 3.0 algorithm. The bulk fluxes of stress (momentum), sensible heat, latent heat and sensible heat due to rain were provided by the COARE 3.0 algorithm. The COARE 3.0 algorithm was also used to compute the 10-m values of wind speed, temperature and humidity. SOG, COG and Gyro were taken from the PSD GPS compass. These were used to compute the wind speed relative to earth. Surface currents are measured by the ship's ADCP and have been QCed by OSU Ocean Mixing group. These were used to compute the wind speed relative to water. The wind speed relative to water are used to compute the fluxes. 10/08/12 New calibrations were applied to the RH measurements from the UConn and ETL sensors. The calibration raised the RH values 1-2%, which modifies slightly the flux estimates and any variabiles adjusted using MO similarity. Values of temperature, specific humidity and relative humidity adjusted to 2-m were added to the matlab and ASCII files. 07/23/13 New calibrations were applied to the RH/Tair measurements from the UConn and ETL sensors using Vaisala factory calibration and a RH/T calibration chamber at UConn. This results in small changes to the previous revision. The sea-snake measurements were reduced by 0.058 based on a comparison with the OSU T-chain SBE device. The TOGA-COARE warm layer correction is applied to the seasnake (causing a small increase during the day. The depth of the sea-snake was set to 5 cm. This value is then used to compute the fluxes using the TOGA-COARE 3.5 algorithm described by Edson et al., 2013: On the exchange of momentum over the open ocean,” J. Phys. Oceanogr., 43, 1589-1610. Therefore, this value of Tsea can be used in the COARE algorithm without the need to run the warm layer code. However, the warm layer correction is saved in the matlab files for investigators that want to convert Tsea back to it measured value. This variable is called dsea in the matlab files and the measured value equals: Tsea_measured=Tsea-dsea. Measurements of the sea temperature and salinity from the thermosalinograph (TSG) are provided. The intake for these measurements is reported as 5 m. The TSG temperature measurements were reduced by 0.05 C based on a comparison with the calibrated sea-snake. Estimates of the significant wave height and phase speed of the dominant wave derived from laser altimeter measurementsare provided. The 1 and 10 minutes values are determined from 1 hour averages, so the variability is representative of that time scale. Values that did not contain enough points resolve 2 second waves (on average) were removed and interpolated through. The phase speed of the dominant wave was determined from the frequency at the spectral peak. The search for the peak was limited to frequencies between 0.01 and 0.5 Hz or 100 down to 2 second waves. These values are preliminary and further refinements are expected with the inclusion of WaMOS data from the ship's radar. A placeholder has been included for the direction of the dominant waves once that becomes available. For now, this value is given by NaN. Also note that the laser altimeter was not operational during Leg 1 and those values are also given by NaN. Measurements of the diffuse solar radiation from a sensor deployed on the top of the bow mast by NCAR are given. The solar zenith angle is provided, which takes into account the hour angle for the local solar time, inclination and latitude. Model estimates of the solar radiation at the surface in the absence of an atmosphere is provided using a solar constant of 1367 W/m2 and allowing for changes due to variations in the distance between Earth and Sun. Model estimates of the clear sky solar radiation (i.e. and atmosphere with no clouds) are provided using a parameterization technique from M. Iqbal in "Physical Climatology for Solar and Wind Energy", 1988, World Scientific, pp. 196-242. The model accounts for absortion and scattering by gases, aerosols, ozone and water vapor. Model coefficients were tuned using observations on the clearest days. 8/20/13 The 10-m wind speed was incorrectly given as the 2-m wind speed in revision 2. This error is corrected in revision 3, i.e., the 10-m values are correctly reported in Ur10 and U10.