Searching the seafloor
Among the 10 PB of research data collections hosted by NCI is the fascinating Geoscience Australia Australian Marine Video and Imagery Collection.
This collection comprises 7 TB of video footage and still photographs of the seafloor offshore from Australia and Antarctica, collected on more than 20 marine surveys since 2007.
“Relatively little is known about what the seafloor around Australia looks like or has living on it,” says custodian of the collection and Senior Marine Ecologist at Geoscience Australia, Dr Rachel Przeslawski.
“Geoscience Australia undertakes a range of marine surveys to improve the understanding and the management of these marine environments.”
By hosting the collection at NCI, Geoscience Australia is providing public access to the thousands of seafloor images and videos it collects each year.
“We often use this imagery for a very specific purpose, such as identifying a fluid seep or classifying habitat, but there is a huge amount of data that could be extracted for other purposes, such as biodiversity research,” says Dr Przeslawski.
“NCI’s facilities have enabled us to open the collection to the wider community.”
The imagery was collected by various video systems –including a video camera, stills camera, lights and location sensors mounted in a frame which is towed behind a ship at 1-2 knots for distances of 1-2 kilometres. Suspended a couple of metres above the seafloor, such systems can record sharp images of marine organisms and their habitats.
For some systems, the footage is sent up a cable to the ship so it can be viewed in real time. Imagery data can be overlain on acoustic data such as multibeam bathymetry and backscatter to examine the relationships between seafloor depth and shape, composition and plant and animal distributions.
Directly observing the seafloor geology and organisms not only allows for rapid characterisation but it also provides the foundation to monitor future changes, says Dr Przeslawski.
“In some regions these surveys build on existing knowledge, but in many areas, particularly in deep offshore sites, these devices provide the first images of the seafloor,” she says.
The usefulness of the collection can be maximised by making it publicly available, says Geoscience Australia Senior Data Strategist Irina Bastrakova.
“In order for scientists and managers to provide regional and national advice in a reasonable timeframe, it’s crucial for marine data to be made publicly available whenever possible,” says Ms Bastrakova.
“Before working with NCI, this data collection was kept in-house with only metadata available online.
“Getting data was a time consuming manual process for users as they had to go through an ordering process at Geoscience Australia’s Sales Centre with DVDs containing data delivered to them by post.
“Working with NCI, we have been able to streamline the whole workflow of creating metadata and harvesting it to the NCI Catalogue, moving data to RDS and applying THREDDS services to ensure consistent discoverability and direct access to data via multiple Australian (e.g. ANDS, IMOS) and world-wide (e.g. GEOSS) portals for the key stakeholders.”