EXP drifters
EXP or "expendable" drifters recorded only temperature (T) in addition to position (± 10 m) and time.
All EXP drifters transmitted data via the Argos satellite network at 30-minute intervals.
Most EXP drifters were deployed in surface configuration (top 1 m of the water), but a few were
drogued with a 10-m long sock drogue (10-m long, 1-m diameter).
Processing of the data included linearly interpolating all data onto a 30-minutely time vector.
The data were snipped, meaning only data collected while in water are provided.
East and north velocity components are also included and were calculated by central-differencing
of position data.
File naming:
EXP drifter files are named according to
Drifter PTT ID_configuration_CruiseDayMonth.txt
For example, a file named 09121_s01_R1W26J.txt contains drifter data recorded by
drifter #09121 starting on July 26th of the 1st RISE cruise aboard the R/V Wecoma.
Cruises were:
R1W - July 2004
R2W - May/June 2005
R3W - August 2005
R4W - May/June 2006
Drifter configuration:
The s01 configuration means that this drifter was in (s)urface configuration which
spanned the top 1 m of the water column. A configuration designation of d25 implies
that the drifter was (d)rogued and the drogue was centered at 25 m depth. This means
the drogue spanned a depth range of 20-30 m depth. Realize that while drogued drifters
followed water at the depth at which they were drogued, they still recorded temperature
data at ~ 1 m depth, not the drogue depth.
Data are in the following units:
Lon - Decimal degrees
Lat - Decimal degrees
Date/Time - GMT
Temperature - Celsius (°C)
Velocity components - (m s-1)