Abstract
Autonomous underwater gliders are becoming important assets of coastal ocean observing systems, but the salinity data may have errors at the depths of thermocline if unpumped CTD sensors are used. Based on the CTD data collected by an autonomous underwater glider on the West Florida Shelf, we examine different salinity corrections, and find that the existing methods successfully adjust the thermal lag effects of a weak thermocline where temperature change is less than 0.7 °C in 3 m of the water column, but fail to calibrate the salinity spikes near a sharp thermocline where temperature change is ~2 °C within 3 m of the water column. These salinity spikes can be effectively removed by applying a median filter in conjunction with the thermal lag correction methods. Thus, we propose an improved and practical approach of glider salinity error correction, which is especially useful for waters of strong stratification and sharp thermocline.
Original language | American English |
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Title of host publication | Coastal Ocean Observing Systems |
DOIs | |
State | Published - Jan 1 2015 |
Keywords
- autonomous underwater glider
- ocean observing
- salinity correction
- thermal lag
- thermocline
- unpumped ctd