top_home

GTS data

The TRITON operational data, which are hourly mean wind, air temperature, relative humidity, air pressure and water temperature, have been distributed every 3-hour through the GTS (Global Telecommunication System).
The TRITON one profile data is divided into 3 data files. They are MET data file, OC1 data file and OC2 data file, because one TRITON buoy has many sensors as 5surface sensors and 13 subsurface sensors.
MET data file includes surface data mainly, OC1 data file includes upper layer subsurface data mainly and OC2 data file includes lower layer subsurface data mainly. Because of this reason, TRITON transmits above mentioned 3 kinds of hourly data files via ARGOS for 24 hours. Among them, synoptic time data, 00Z, 03Z, 06Z,...... and the latest data file on GTS separately go on GTS. (We receive3 kinds of data for 24 hours every day from all TRITON buoys, and create daily data as TAO/TRITON web data.)

TRITON GTS DATA STREAM:
TRITON has many sensors. So each buoy can't transmit those data in one file through ARGOS. Then, we split it to three files, as follows;

- MET data file
     This file includes the following meteorological elements;
          wind direction
          wind speed
          air temperature
          relative humidity
          atmospheric pressure
          SST
- OC1 data file
     This file includes the following subsurface data;
          1.5m water temperature = SST
          water temperature of 25m , 50m , 75m , 100m , 300m , 750m
- OC2 data file
     This file includes the following subsurface data;
          water temperature of 125m , 150m , 200m , 250m , 500m

Those three files are transmitted to the ARGOS center (CLS) and are distributed all over the world through GTS. At CLS, the above mentioned three files are combined into one complete hourly file, which is consist of MET data file, OC1 data file and OC2 data file.

Now GTS distributes the complete hourly files on synoptic time schedule (every 3 hours), AND ALSO the latest files on satellite pass. In some cases, the latest file is consist of incomplete file, such as
only MET data or
only OC2 data or
OC1+OC2 or .....and so on.


Followings are Q & A for GTS data users.

Q1: Is one of the profiles representative of the daily mean ?

A1: No. Only hourly data go on GTS, no daily mean data on GTS.

Q2: Some profiles have data at different levels reported for the same time (03:00Z), whilst for others the location is slightly different (00:00Z). In another case two profiles are reported for the same time but one with incomplete levels (15:00Z). Should we be ignoring some of this data ? Which are the correct profiles ?

A2: As above TRITON GTS DATA STREAM, we divide one TRITON profile data into 3 data files, and we distribute each file on GTS. So users will get 3 data files in the maximum condition for the same time, especially for the synoptic time. TRITON data distributed on GTS is not a daily data but a hourly data. So the location data as well as the other observed data distributed at each synoptic time are correct.

Q3: After further investigation it seems that for almost all the TRITON mooring, there are some profiles missing the section between 125m-500m (excluding 300m!) and others that only include these. There are a couple of cases where there are two reports for the same time with complementary profile.

A3: You might get the synoptic time data, and also latest file of only OC2 data file.