Air-deployable profiling floats

Author Posting. © The Oceanography Society, 2017. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 30, no. 2 (2017): 29–31, doi:10.5670/oceanog.2017.214.We describe the development of a small profiling float, the ALAMO (Air-Launched Autonomous Micro-Observer), that observes upper-ocean structure over a year. These floats can be launched from any aircraft equipped with an “A-sized” launch tube, or from the door of any other aircraft. Profiling floats have found wide use in the oceanographic community, from their original design in the World Ocean Circulation Experiment (Davis et al., 1992) to their current widespread usage in the Argo program (Riser et al., 2016). The utility of profiling floats derives from their relative affordability and their autonomous nature once deployed. The ALAMO float works on the same principles as the ALACE (Autonomous Lagrangian Circulation Explorer) profiling float designed by Davis et al. (1992), which developed into the SOLO (Sounding Oceanographic Lagrangian Observer) profiling floats used in the Argo program today (Davis et al., 2001). The ALAMO float represents a natural progression of those earlier designs.This work was supported by NOAA grant NA13OAR4830233 as part of CINAR Sandy Supplemental funding and ONR grant N00014-15-12293

The air-launched autonomous micro observer

Author Posting. © American Meteorological Society, 2022. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of the Atmospheric and Oceanic Technology 39(4), (2022): 491–502, https://doi.org/10.1175/jtech-d-21-0046.1.The Air-Launched Autonomous Micro Observer (ALAMO) is a versatile profiling float that can be launched from an aircraft to make temperature and salinity observations of the upper ocean for over a year with high temporal sampling. Similar in dimensions and weight to an airborne expendable bathythermograph (AXBT), but with the same capability as Argo profiling floats, ALAMOs can be deployed from an A-sized (sonobuoy) launch tube, the stern ramp of a cargo plane, or the door of a small aircraft. Unlike an AXBT, however, the ALAMO float directly measures pressure, can incorporate additional sensors, and is capable of performing hundreds of ocean profiles compared to the single temperature profile provided by an AXBT. Upon deployment, the float parachutes to the ocean, releases the air-deployment package, and immediately begins profiling. Ocean profile data along with position and engineering information are transmitted via the Iridium satellite network, automatically processed, and then distributed by the Global Telecommunications System for use by the operational forecasting community. The ALAMO profiling mission can be modified using the two-way Iridium communications to change the profiling frequency and depth. Example observations are included to demonstrate the ALAMO’s utility.This work was supported by the National Oceanographic and Atmospheric Administration under Grants NA13OAR4830233 (as part of CINAR Sandy Supplemental funding from the Disaster Relief Appropriations Act of 2013) and NA14OAR4320158 and by Office of Naval Research under Grants N0001416WX01384, N0001416WX01262, and N000141512293. ALAMO floats are commercially available from MRV Systems, LLC (https://www.mrvsys.com)

TOGA COARE mooring deployment, mooring check-out and mooring recovery cruises : R/V Wecoma 7 October-1 November 1992, R/V Le Noriot 2 December-15 December 1992, R/V Wecoma 27 February-11 March 1993

The Tropical Ocean - Global Atmosphere Coupled Ocean - Atmosphere Response Experiment (TOGA COARE) was conceived in order to improve understanding of the principal processes responsible for coupling of the ocean and atmosphere in the western Pacific warm pool region. Field work for TOGA COARE was concentrated in an Intensive Flux Array (IFA) and included a variety of atmospheric and oceanic platforms. The Upper Ocean Processes Group (UOPG) was involved in TOGA COARE through the preparation, deployment, and recovery of a heavily instrumented surface mooring for the observation of air-sea fluxes and oceanic temperature, salinity, and currents in the upper 300 m. The mooring was deployed at 1°,45.27'S, 155°,59.73'E on 21 October 1992 in 1744 m of water. An instrument check-out cruise was undertaken in December of 1992 in order to evaluate the meteorological systems on the buoy. The mooring was recovered on 4 March 1993. This report describes mooring deployment operations, the instrument check-out cruise, and the mooring recovery. UOPG personnel also assisted with the deployment and recovery of five other moorings as a part of the COARE IFA and these operations are discussed.Funding provided by the National Science Foundation under grants OCE-9110554 and OCE-9110559

Near-Real-Time Acoustic Monitoring of Beaked Whales and Other Cetaceans Using a Seaglider (TM)

Correction 10 Aug 2012: Klinck H, Mellinger DK, Klinck K, Bogue NM, Luby JC, et al. (2012) Correction: Near-Real-Time Acoustic Monitoring of Beaked Whales and Other Cetaceans Using a Seaglider™. PLOS ONE 7(8): 10.1371/annotation/57ad0b82-87c4-472d-b90b-b9c6f84947f8.In most areas, estimating the presence and distribution of cryptic marine mammal species, such as beaked whales, is extremely difficult using traditional observational techniques such as ship-based visual line transect surveys. Because acoustic methods permit detection of animals underwater, at night, and in poor weather conditions, passive acoustic observation has been used increasingly often over the last decade to study marine mammal distribution, abundance, and movements, as well as for mitigation of potentially harmful anthropogenic effects. However, there is demand for new, cost-effective tools that allow scientists to monitor areas of interest autonomously with high temporal and spatial resolution in near-real time. Here we describe an autonomous underwater vehicle – a glider – equipped with an acoustic sensor and onboard data processing capabilities to passively scan an area for marine mammals in near-real time. The glider was tested extensively off the west coast of the Island of Hawai'i, USA. The instrument covered approximately 390 km during three weeks at sea and collected a total of 194 h of acoustic data. Detections of beaked whales were successfully reported to shore in near-real time. Manual analysis of the recorded data revealed a high number of vocalizations of delphinids and sperm whales. Furthermore, the glider collected vocalizations of unknown origin very similar to those made by known species of beaked whales. The instrument developed here can be used to cost-effectively screen areas of interest for marine mammals for several months at a time. The near-real-time detection and reporting capabilities of the glider can help to protect marine mammals during potentially harmful anthropogenic activities such as seismic exploration for sub-sea fossil fuels or naval sonar exercises. Furthermore, the glider is capable of under-ice operation, allowing investigation of otherwise inaccessible polar environments that are critical habitats for many endangered marine mammal species

Near-Real-Time Acoustic Monitoring of Beaked Whales and Other Cetaceans Using a Seaglider™

In most areas, estimating the presence and distribution of cryptic marine mammal species, such as beaked whales, is extremely difficult using traditional observational techniques such as ship-based visual line transect surveys. Because acoustic methods permit detection of animals underwater, at night, and in poor weather conditions, passive acoustic observation has been used increasingly often over the last decade to study marine mammal distribution, abundance, and movements, as well as for mitigation of potentially harmful anthropogenic effects. However, there is demand for new, cost-effective tools that allow scientists to monitor areas of interest autonomously with high temporal and spatial resolution in near-real time. Here we describe an autonomous underwater vehicle – a glider – equipped with an acoustic sensor and onboard data processing capabilities to passively scan an area for marine mammals in near-real time. The glider was tested extensively off the west coast of the Island of Hawai'i, USA. The instrument covered approximately 390 km during three weeks at sea and collected a total of 194 h of acoustic data. Detections of beaked whales were successfully reported to shore in near-real time. Manual analysis of the recorded data revealed a high number of vocalizations of delphinids and sperm whales. Furthermore, the glider collected vocalizations of unknown origin very similar to those made by known species of beaked whales. The instrument developed here can be used to cost-effectively screen areas of interest for marine mammals for several months at a time. The near-real-time detection and reporting capabilities of the glider can help to protect marine mammals during potentially harmful anthropogenic activities such as seismic exploration for sub-sea fossil fuels or naval sonar exercises. Furthermore, the glider is capable of under-ice operation, allowing investigation of otherwise inaccessible polar environments that are critical habitats for many endangered marine mammal species

Glider track (colored line) and surfacing positions of tagged Cuvier's beaked whale (black dots) on 3 November 2009.

<p>Glider depth is color-coded. Black stars indicate position of glider at times of beaked whale surfacing events. Red star indicates position of glider when Cuvier's beaked whale clicks were acoustically detected by the glider during the mission (detections were verified in the post deployment analysis). The acoustic system was operated at depth between 500 m and 1000 m indicated by greenish/bluish colors. Times are UTC.</p

Example of unknown echolocation clicks likely produced by beaked whales.

<p><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036128#pone-0036128-g007" target="_blank">Figure 7a</a> shows a spectrogram of the ‘double click’. Recording was made at 500 m depth. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036128#pone-0036128-g007" target="_blank">Figure 7b</a> represents a spectrum of the click (solid line) and the background noise level at the time of the recording (dotted line). Spectrogram parameters used to generate plots: frame size 32 samples (0.16 ms), FFT size 128 samples (0.64 ms), overlap 94% (0.15 ms), and Hamming window, for a spectrum filter bandwidth of 24.6 kHz. Data were high-pass filtered at 10 kHz prior to processing.</p