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The physical mechanisms that maintain and deliver phytoplankton and Antarctic krill biomass, potentially increasing prey availability to predators, are not well known. The short surface ocean residence times of 1-2 days over Palmer Deep is in conflict with the prevailing hypotheses that local growth support phytoplankton at the base of the food web in these biological hotspots. Instead, the implication is that horizontal dynamics are likely more important to maintaining these biological hotspots than local upwelling. However, coincident measures of phytoplankton, prey fields, and predator locations in their advective context have not been made to establish the ecological importance of horizontal flow. To better understand these important mechanisms, we are deploying a purpose built integrated polar observatory consisting of high frequency radar, coordinated gliders, small boat surveys, and moorings. This integrated polar observatory will enable us to simultaneously sample across the entire food web from the phytoplankton and prey fields to the top predators to understand the ocean features that support life in these polar systems. For the first time in this region, we will: 1) integrate sensors and technologies to simultaneously map phytoplankton blooms, krill aggregations, and top predator foraging relative to dynamic ocean features; 2) integrate these observations with a high-resolution (1.5 km) 3-D dynamic model simulation of the entire WAP coastal ocean to generalize our field measurements to other known hotspots along the WAP through simulation, and to determine which physical mechanisms lead to the maintenance of these hotspots.

Along the Western Antarctic Peninsula, ecological hotspots are spatially coherent with submarine canyons and have persisted for millennia. Palmer Deep Canyon, a representative hotspot, is known to have higher phytoplankton biomass than the surrounding non-canyon regions. The physical mechanisms that maintain and deliver phytoplankton and Antarctic krill biomass, potentially increasing prey availability to predators, are not well known. To better understand these important mechanisms, we deployed a purpose built integrated polar observatory consisting of high frequency radar, coordinated gliders, and moorings. The gliders identified a depth dependent influence of the underlying canyon bathymetry on physical and biological variability. A series of simulated particle release experiments in the HF radar current maps were used to estimate surface residence time and connectivity across the canyon. With an average residence time of 2 days, our analysis indicates that the elevated phytoplankton biomass over the central canyon is transported into and out of the hotspot on time scales much shorter than the observed phytoplankton growth rate, suggesting that the canyon may not act as an incubator of phytoplankton productivity as previously suggested. It may instead serve more as a conveyor belt of phytoplankton biomass produced elsewhere, continually replenishing the phytoplankton biomass for the local krill community, which in turn supports numerous top predators.

The Palmer Deep submarine canyon on the Western Antarctic Peninsula provides a conduit for upwelling of relatively warm, nutrient rich waters which enhance local primary production and support a food web productive enough to sustain a large top predator biomass. In an analysis of ten years of satellite-tagged penguins, showed that circulation features associated with tidal flows may be a key driver of nearshore predator distributions. During diurnal tides, the penguins feed close to their breeding colonies and during semi-diurnal tides, the penguins make foraging trips to the more distant regions of Palmer Deep. It is hypothesized that convergent features act to concentrate primary producers and aggregate schools of krill that influence the behavior of predator species. The initial results from a six month deployment of a High Frequency Radar network in Palmer Deep are presented in an attempt to characterize and quantify convergent features. During a three month period from January through March 2015, we conducted in situ sampling consisting of multiple underwater glider deployments, small boat acoustic surveys of Antarctic krill, and penguin ARGOS-linked satellite telemetry and time-depth recorders (TDRs). The combination of real-time surface current maps with adaptive in situ sampling introduces High Frequency Radar to the Antarctic in a way that allows us to rigorously and efficiently test the influence of local tidal processes on top predator foraging ecology

Project CONVERGE, funded by the National Science Foundation Office of Polar Programs, is deploying a coordinated ocean observing network to better understand ecological connections along the Western Antarctic Peninsula (WAP). Partners from Rutgers University, the University of Alaska, Fairbanks (UAF), Oregon State University, the University of Delaware, and the Polar Oceans Research Group deployed a multiplatform-observing network that includes gliders, animal telemetry, active acoustics for zooplankton distributions, and CODAR High Frequency Radar (HFR). The three-site network was deployed in November of 2014 and provided hourly surface current maps through the following austral summer. This study targets data collected between January and February 2015. Here we focus on Palmer Deep eddy and the tidal currents as they transition from diurnal to semi-diurnal regimes throughout the study period. These data are helping us better understand the links between alternating tidal regimes and the foraging behavior of the local Adelie penguin populations. This analysis has further implications for future research as the region goes through dramatic climate change.

With the increased interest and presence that the U.S. Coast Guard has in the Arctic [1] there is also a rising need for increased Maritime Domain Awareness (MDA) from autonomous sensors in this area. From June through November 2012, University of Alaska, Fairbanks (UAF) deployed and maintained three Long Range SeaSonde@ HF Surface Wave Radars operating in the 5 MHz band and two High Resolution SeaSondes operating in the 25 MHz band to map hourly ocean surface currents in the Chukchi Sea during the summer and fall. With funding from the U.S. Department of Homeland Security (DHS) National Center for Islands, Maritime, and Extreme Environments Security (CIMES), UAF partnered with Rutgers University, a partner in the DHS Center for Secure and Resilient Maritime Commerce (CSR) and CODAR Ocean Sensors to demonstrate multi-use MDA capability of SeaSondes to provide vessel detections simultaneously with surface current maps near Barrow, Alaska. The Arctic region poses challenges to HF Radar vessel detection including: remote locations requiring specialized shelter, power and communications; extreme weather; the presence of ice floes, which have their own Doppler echoes in addition to sea clutter; and a different radio environment with auroral influences. Vessel detection results are shown with corresponding AIS data, the effect of diurnal ionosphere activity on HF Doppler spectra is shown and the performance of the UAF remote power module (RPM) is discussed.

The arctic could be ice free during the summer by as early as 2040 [1]. This could alter the dominant shipping routes between Europe and Asia. The ability to monitor this traffic is hindered by lack of sensors, communication and power for the sensors. SeaSonde High Frequency radars were installed along the northwest corner of Alaska from July to December 2012. These radars were able to make simultaneous measurements of ocean surface currents as well as measure the position and velocity of vessels passing by the radar. This successful demonstration proves that High Frequency radar can be a valuable tool for providing maritime domain awareness and persistent surveillance capabilities in the arctic.

We present high-resolution space-time dependent observations of circulation and stratification features in the Chukchi Sea, Arctic Ocean from an observing system consisting of AUV gliders, HF radars, drifters, and sub-surface moorings. These unique high-latitude observations show a more complex, dynamic and high-energy ocean environment than previously reported in the Arctic. We also present examples of imminent technology needs for high-latitude areas.

High-frequency shore-based radars (HFR) collect hourly, real-time surface current data over broad areas of the coastal ocean and yield insights on the time-varying circulation, predict oil spill trajectories, evaluate circulation models, and in case of a spill, provide responders with real-time data on spill evolution. HFR requires 7.5 Kilowatt-hours/day of power but the lack of power availability inhibits HFR use in Alaska. We developed a modular, autonomous remote power module (RPM) for arctic environments (Figure 1). The RPM is designed to reduce operating costs through a reliance on renewable (wind and solar) energy. Fossil fuel based generators are costly due to frequent maintenance requirements, limited life expectancies and ongoing logistics logistics and fuel costs. The RPM consists of commercial off-the-shelf components tested to ensure low electromagnetic interference and supplies the power requirements of a typical CODAR Ocean Sensors Seasonde?, a high-speed satellite communications link, a small meteorological station and power monitoring and control equipment. The total power requirements of the electronics are approximately 10 Kilowatt-hours per day.