This file contains general
guidelines for research vessels operating around TAO moorings (both
surface and subsurface). We recommend that chief
scientists contact NDBC prior to cruise departure for
more specific information regarding a particular area
of operations, including the positions of surface and
Some general information and guidelines for
operating around these moorings are as follows:
or further information contact NDBC.
- A safe operating distance is at least 2
nautical miles downwind and/or downcurrent from a
- CTD casts up to 1000 m depth can be made
at this distance. CTD casts to greater than 1000 m
depth should be made at distances proportionately
greater than 2 nautical miles.
- No expendibles (e.g. XBTs) within 2
nautical miles of a mooring.
- Subsurface current meter moorings are
equipped with a 153.6 kHz acoustic Doppler current
profiler (ADCP) which samples for 15 minutes
beginning at the top of each hour. Ships operating
at distances of 2 miles from the buoy will not
interfere with moored ADCP data collection at these
- No refuse or other jetsam thrown overboard
within 5 nautical miles of the
- Positions of TAO surface buoys can change
over the course of a few days to a week (depending
on the current regime) by up to 2 nautical miles.
This is the diameter of a "watch circle" within
which the buoy moves due to the stretch of the
nylon mooring line.
The TAO Project Office is interested in
obtaining ship measurements within a few miles of
a mooring for quality control purposes. No
special efforts need to be taken for collection
of the shipboard data, except to follow the
general guidelines above. The following
measurements would be appreciated:
- CTD casts to at least 500 m
- Shipboard ADCP data for comparison
with moored ADCPs.
- Shipboard weather observations (wind
speed and direction, wet and dry bulb
temperatures, cloud amount, precipitation, sea