- README for Surface Meteorological Dataset -


(1) One-minute mean data

"sfcm01m_leg1(2).dat" contains 1-minute mean values (time stamp at the beginning of the average)
of surface meteorological data as ASCII format. Original data are stored every 6 seconds. After
removing maximum/minimum data for each parameter from 10 data samples (i.e., 8 samples), simple
average was calculated.
These data are produced from two surface meteorological instruments (MIRAI Surface Meteorological
observation system : SMET, Shipboard Oceanographic and Atmospheric Radiation measurement system : 
SOAR) and one sea surface water monitoring system (EPCS).
Details of these systems can be found at "http://www.jamstec.go.jp/mirai/track_line/MR06-05.html".

 
Parameters and their units contained are as follows;
  Time in UTC expressed as YYYYMMDDHHMM
  Time in Julian day (1.0000 = January 1, 0000Z), 
  longitude (degE)
  latitude  (degN)
  pressure (hPa)
  air temperature (degC)
  dew point temperature (degC)
  relative humidity (%)
  sea surface temperature (degC)
  zonal wind component (m/sec)
  meridional wind component (m/sec)
  precipitation (mm/hr)
  downward shortwave radiation (W/m2)
  and downward longwave radiation (W/m2).

Missing values are expressed as "9999".

Sensor types and their equipped height from the sea level are as follows.
  Barometer (pressure)    : Setra System, Model-370    ... 13 m (converted to 0 m level value)
  Thermometer (T, RH)     : Vaisala, HMP45A            ... 21 m
  Thermometer (SST)       : SeaBird Electronics, SBE3S ... -5 m
  Anemometer (wind)       : R. M. Young, 05106         ... 25 m
  Rain gauge (rainfall)   : R.M.Young, 50202           ... 24 m
  Radiometer (short wave) : Eppley, PSP                ... 25 m
  Radiometer (long wave)  : Eppley, PIR                ... 25 m

Pressure and T/RH data are adopted from SMET, SST from EPCS, and others from SOAR system, respectively.



(2) Ten-minute mean data  with skin Sea Surface Temperature data

"smet10m_sst.dat" contains 10-minute mean values (time stamp at the end of the average)
of surface meteorological data as ASCII format.
These data were produced from "sfcm01m_leg1(2).dat" and Sea-snake/ISAR skin-SST data.
Sea-snake is a floating-type thermistor which deployed from the bow of ship. It usually measures
sea temperature near the skin about a few centimeters depth. We used thermistor (107 Campbell, USA).
As for the ISAR (Infrared Sea surface temperature Autonomous Radiometer), please see "ISAR_RMRCo.pdf".
These two systems were only deployed during the first leg of the MIRAI cruise.
 
Parameters and their units contained are as follows;
  Time in UTC expressed as YYYYMMDDHHMM
  Time in Julian day (1.0000 = January 1, 0000Z)
  longitude (degE)
  latitude  (degN)
  pressure  (hPa)
  air temperature (degC)
  dew point temperature (degC)
  relative humidity (%)
  sea surface temperature by Intake    (degC)
  sea surface temperature by Sea-snake (degC)
  sea surface temperature by ISAR      (degC)
  zonal wind component (m/sec)
  meridional wind component (m/sec)
  precipitation (mm/hr)
  downward shortwave radiation (W/m2)
  downward longwave radiation (W/m2).

Missing values are expressed as "9999".


For more information, please contact to Kunio Yoneyama (yoneyamak @ jamstec.go.jp).