Prior to February 2005, ATLAS moorings transmitted data 8 hours per day (0600-1000 and 1200-1600 local times). Moorings deployed since the beginning of 2005 transmit 16 hours per day
from 0000-0400, 0600-1000, 1200-1600, and 1800-2200 local times. (Click here for equivalent GMT transmit windows). Hourly surface messages are generated whenever Argos receives a satellite pass, typically 8-14 times per day for ATLAS moorings. The shift from 8 hour to 16 hour per day transmissions, combined with the use of all available NOAA satellites for data transmission, has resulted in a quadrupling of real-time surface TAO data reaching operational centers since 2005.
The subsurface temperature and salinity data are available on the GTS as daily averages with a time stamp of 0000z at the end of the average period. Only one subsurface message per day per buoy is available.
As part of the data quality monitoring, PMEL identifies and informs Service Argos of data that should not be submitted to the GTS. In turn, Service Argos makes available to PMEL data which are submitted to the GTS. PMEL compares these data for consistency checks with data processed at PMEL. Since February 2007, NDBC has assumed responsibility for quality control of TAO data on the GTS. PMEL continues to quality control PIRATA and Indian Ocean data.
Typically, about 80% to 90% of data received at PMEL make it onto the GTS. Due to a combination of the ATLAS sampling and transmission schedule, telemetry paths of the NOAA satellite system, and Service Argos processing time, there is a finite time lag between observations and availability on the GTS. Over half of the TAO data placed on the GTS are available within 3 hours or less and over 90% are available within 7 hours.
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