One S-PALACE float was deployed in the Sargasso Sea in February, 1996. It obtained 55 temperature profiles at 7-day intervals before the sensor failed. This float is still sending back its position, even though the temperature and conductivity data associated with it are no longer good. We have received more than 150 positions from this float, the greatest number of transmissions sent from one of our floats. A Labrador Sea float, #24215, was deployed six months after 24211, and also transmits at 7 day intervals. The data from 24215 is still good, so it has sent the most good data, but float 24211 has still sent back more positions. Also, during the time float 24211 was deployed, it observed the effects of hurricane Bob, in August, 1996.
The chart above shows the float's movement during the deployment. The solid red line segments show the float's movement while on the surface telemetering the data. The dashed line segments show the movement between the last position of one surface interval to the first position from the next transmission. This is the time it is resting underwater at its ballast depth. Colors code the dashed lines for years: green is for 1996 : blue is for 1997 : violet is for 1998.
The plot below shows how the temperature profiles acquired by this float changed with time. Between intervals 48 and 49, the float probably moved from warm Sargasso Sea water into a cold core ring of the Gulf Stream as it crossed the New England Seamounts. It appears to have meandered in and out of the feature before the temperature sensor failed. The change at interval 49 might also be due to the beginning of the failure of the temperature sensor, but we will never know for certain.
S-PALACE
main page