Advancing interdisciplinary sea ice research with a new under-ice remotely operated vehicle and autonomous observatories
To better observe the ongoing changes in the polar climate- and ice-associated ecosystem, the Alfred-Wegener-Institute is developing new technologies for ice-tethered observations in the framework of the Helmholtz initiative “FRontiers in Arctic marine Monitoring (FRAM)”. This includes the development and regular deployment of a new versatile remotely operated vehicle (ROV) for interdisciplinary observations under sea ice as well as the development of autonomous drifting observatories enabling the continuous monitoring of various physical and biogeochemical parameters in the sea ice and upper ocean. Here we introduce the concept and design and first results of the new ROV system, which combines a comprehensive, multidisciplinary sensor suite into a lightweight system that can be operated by two persons from the ice. We highlight results from the first Arctic deployment in autumn 2016, including data from standard oceanographic instrumentation, fluorometers, hyperspectral radiometers, nitrate, pH, diverse still and video cameras as well as various acoustic sensors including upward looking bathymetric multibeam sonar mapping of the under-ice topography. The vehicles further potential for added scientific payload and manipulation capabilities is currently developed for the next mission. While the ROV system explores spatial variability of the sea ice system, autonomous drifting buoys are able to monitor the seasonal evolution of the ice pack over several months/years. We complement the ROV data with first results from an ice-tethered ocean profiling system equipped with bio-optical sensors that retrieved the first full-year autonomous timeseries in the transpolar drift, and a newly developed thermistor-string IMB upgraded with a solar radiation package, webcam, as well as a triplet fluorometer, and oxygen optode to chart the ice-associated biological activity that is missed by the ocean profiler. The results indicate that all platforms recorded traces of a widespread autumn under-ice bloom in the transpolar drift, likely caused by the low sea ice concentration in summer 2016.
AWI Organizations > Climate Sciences > Sea Ice Physics
AWI Organizations > Biosciences > Joint Research Group: Deep Sea Ecology and Technology