ARGOS Time Series

ARGOS is a satellite-based location system allowing you to locate MOBY to within 150 to 1500 meters. The ARGOS unit on MOBY transmits MOBY's position and ARGOS operational parameters on a daily to weekly basis. If MOBY breaks free of it's mooring the ARGOS unit enables the MOBY team to track and recover the buoy.

In each ARGOS email the latitude and longtitude is assigned a position code or class. This codes tell you the estimated error associated with the position. The table below is from the ARGOS manual, the legends in the last two figures show these codes. The larger the circles the more accurate the position.

Starting on March 15, 2011 MOBY ARGOS data are processed using the new Kalman filtering algorithm. This means that even the normally low accuracy Position Classes are more likely to produce useful positions. For more information on the Kalman filtering algorithm go to the ARGOS Kalman FAQ webapge.

Position Class Type Estimated error Number of messages received
per satellite pass
Numeric code
in file listing
G GPS < 100m 1 message or more 6
3 ARGOS < 250m 4 messages or more 5
2 ARGOS 250m < < 500m 4 messages or more 4
1 ARGOS 500m < < 1500m 4 messages or more 3
0 ARGOS > 1500m 4 messages or more 2.5
A ARGOS No accuracy estimation 3 messages 2
B ARGOS No accuracy estimation 2 messages 1
Z ARGOS Invalid location 0

Argos Data Listing | Argos Course and Dist Listing | Argos Web Site

Stephanie Flora - Moss Landing Marine Laboratories