Saturation diving is diving for periods long enough to bring all tissues into equilibrium with the partial pressures of the inert components of the breathing gas. (https://en.wikipedia.org/wiki/Saturation_diving)
A stream which has water only in some periods. (FAO. 1978. Glossary of inland fishery terms, EIFAC Occasional Paper No. 12 https://www.fao.org/4/ae987b/AE987B01.htm)
Note
An ephemeral stream is one that only exists for a short period following precipitation or snowmelt. It is not the same as an intermittent or seasonal stream, which exists for longer periods, but is not perennial
Drifting buoys are generally attached to some form of drogue or sea-anchor, are easy to deploy, are relatively inexpensive to operate and reliably measure the atmosphere and ocean surface conditions, for an average of 18 months. Drifting buoys have a long history of use in oceanography, principally for the measurement of currents. There have also been many types of drifting buoys used for meteorological purposes. (http://dbcp.jcommops.org/platforms/types.html)
