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The Davis Strait observing system was established in 2004 to advance understanding of the role of Arctic – sub-Arctic interactions in the climate system by collecting sustained measurements of physical, chemical and biological variability at one of the primary gateways that connect the Arctic and subpolar oceans. Efforts began as a collaboration between researchers at the University of Washington’s Applied Physics Laboratory and the Canadian Department of Fisheries and Ocean’s Bedford Institute of Oceanography, but has grown to include researchers from the Greenland Institute of Natural Resources, Greenland Climate Institute, Danish Technological University, University of Alberta and University of Colorado, Boulder. The project is a component of the NSF Arctic Observing and Atlantic Meridional Overturning Networks, and the international Arctic-Subarctic Ocean Flux (ASOF) program, Global Ocean Ship-Based Hydrographic Investigations Program (GO-SHIP), Global Ocean Acidification Observing Network (GOA-ON), Arctic Monitoring Assessment Programme (AMAP) and OceanSITES system. A mooring array spanning the entire Davis Strait has been in place nearly continuously since September 2004 as part of the Davis Strait observing system, collecting year-round measurements of temperature, salinity and velocity extending to the sea surface/ice-ocean interface. The mooring typically included 14 moorings, 4 on each shelf and 6 in the center of the strait, that are recovered and data offloaded each autumn. Exact mooring location, instrumentation, and deployment duration varied slightly over time. This dataset consists of Level 2 data from the Davis Strait mooring array. Each file contains data from a single sensor (e.g., MicroCAT temperature and salinity measurements or ADCP velocity measurements) at one mooring site collected during a single deployment (typically one year long). Files also include quality control flags. More details about the project can be found at https://iop.apl.washington.edu/project.php?id=davis.
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A Hybrid Lister‐Outrigger Probe for Rapid Marine Geothermal Gradient Measurement
Abstract We have successfully constructed and tested a new, portable, Hybrid Lister‐Outrigger (HyLO) probe designed to measure geothermal gradients in submarine environments. The lightweight, low‐cost probe is 1–3 m long and contains 4–12 semiconductor temperature sensors that have a temperature resolution of 0.002°C, a sample rate of <2 s, and a maximum working depth of ~2,100 m below sea level (mbsl). Probe endurance is continuous via ship power to water depths of ~700 mbsl or up to ~1 week on batteries in depths >500 mbsl. Data are saved on solid‐state disks, transferred directly to the ship during deployment via a data cable, or transmitted via Bluetooth when the probe is at the sea surface. The probe contains an accelerometer to measure tilt, internal pressure, temperature, and humidity gauges. Key advantages of this probe include (1) near‐real‐time temperature measurements and data transfer; (2) a low‐cost, transportable, and lightweight design; (3) easy and rapid two‐point attachment to a gravity corer, (4) short (3–5 min) thermal response times; (5) high temporal/spatial resolution; and (6) longer deployment endurance compared to traditional methods. We successfully tested the probe both in lakes and during sea trials in May 2019 offshore Montserrat during the R/V Meteor Cruise 154/2. Probe‐measured thermal gradients were consistent with seafloor ocean‐drilling temperature measurements. Ongoing probe improvements include the addition of real‐time bottom‐camera feeds and long‐term (6–12 months) deployment for monitoring.
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- Award ID(s):
- 1926729
- PAR ID:
- 10450193
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Earth and Space Science
- Volume:
- 8
- Issue:
- 1
- ISSN:
- 2333-5084
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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