Sampling schemes for instruments in Massachusetts Bay at

# U.S. Geological Survey long-term moorings

+------+----------+---------+---------+-------------------------------+
| **Si | *        | **Ins   | **Sam   | **Variables and sampling      |
| te** | *Mooring | trument | pling** | scheme**                      |
|      | type**   | type**  |         |                               |
|      |          |         | **int   |                               |
|      |          |         | erval** |                               |
+------+----------+---------+---------+-------------------------------+
| A    | Su       | M       | 300 s   | One sample of T and C every   |
|      | bsurface | icrocat |         | 300 s.                        |
+------+----------+---------+---------+-------------------------------+
|      |          | VMCM    |         | One sample of V every 300 s.  |
+------+----------+---------+---------+-------------------------------+
|      |          | Seacat  | 300 s   | One sample of T, C and Tr     |
|      |          |         |         | every 300 s.                  |
+------+----------+---------+---------+-------------------------------+
|      |          | Time    | 9 days  | Sediment in collection bottle |
|      |          | -series |         |                               |
|      |          | s       |         |                               |
|      |          | ediment |         |                               |
|      |          | trap    |         |                               |
+------+----------+---------+---------+-------------------------------+
|      |          | Tube    | Dep     | Sediment in trap              |
|      |          | trap    | loyment |                               |
+------+----------+---------+---------+-------------------------------+
| A    | Tripod   | ADCP    | 900 s   | Average of 300 one second     |
|      |          |         |         | pings every 900 s in 2 m bins |
+------+----------+---------+---------+-------------------------------+
|      |          | MIDAS   | 300 s   | 300 s averages of V (BASS)    |
|      |          |         |         | and P at .5 Hz. Single sample |
|      |          |         |         | of T, C and Tr every 300 s.   |
+------+----------+---------+---------+-------------------------------+
|      |          | Camera  | 4 hours | Single picture                |
+------+----------+---------+---------+-------------------------------+
|      |          | Tube    | Dep     | Sediment in trap              |
|      |          | trap    | loyment |                               |
+------+----------+---------+---------+-------------------------------+
| B    | Su       | M       | 300 s   | One sample of T and C every   |
|      | bsurface | icrocat |         | 300 s.                        |
+------+----------+---------+---------+-------------------------------+
|      |          | Tube    | Dep     | Sediment in trap              |
|      |          | trap    | loyment |                               |
+------+----------+---------+---------+-------------------------------+
|      |          | Time    | 9 days  | Sediment in collection bottle |
|      |          | -series |         |                               |
|      |          | s       |         |                               |
|      |          | ediment |         |                               |
|      |          | trap    |         |                               |
+------+----------+---------+---------+-------------------------------+
| B    | Tripod   | ADCP    | 900 s   | Average of 300 one-second     |
|      |          |         |         | pings every 900 s in 2 m      |
|      |          |         |         | bins.                         |
+------+----------+---------+---------+-------------------------------+
|      |          |         |         |                               |
+------+----------+---------+---------+-------------------------------+

**Variables Key:** C = Conductivity; OBS = Optical Backscatter; P =
Pressure; T = Temperature; Tr = Light transmission; V = Current
velocity.

**Instrument Key:** ADCP = Acoustic Doppler current Profiler; MIDAS =
USGS Multiparameter Intelligent Data Logging System; SBE-39 = pressure
data logger.