What is the typical sea ice concentration east of the Antarctic Peninsula in February, or what was the chlorophyll concentration in the Ross Sea in December 2015? These and more questions are now answered by NILAS, a new interactive tool developed by researchers from the Australian Antarctic Division, which allows a wide range of ice and ocean parameters around Antarctica to be viewed in combination. Even uploading your own data is possible. Non-scientists can also access NILAS to track sea ice cover, for example.
Southern Ocean ice and ocean data such as daily or monthly sea ice concentration, its long-term extent, chlorophyll concentration (an indicator of phytoplankton density), sea surface temperature, etc. can be easily accessed by Antarctic researchers and used for their research. Until now, however, these data were only available individually. With the new, freely available tool NILAS, it is now possible to view all these parameters combined, from the past and in real time. Furthermore, own measurement data or planned or past ship courses can be overlaid on the data integrated in NILAS. This will provide researchers with a powerful tool for planning expeditions, analyzing collected data and for future research, according to Dr. Petra Heil, sea ice scientist in the Australian Antarctic Division, in an AAD news release.
NILAS includes both current and historical data going back to 1980 for sea ice, 1981 for sea surface temperatures, and 1998 for chlorophyll concentrations. In addition to sea ice extent and concentration, NILAS also contains data on the so-called sea ice freeboard, which indicates the height of the ice above the sea surface. According to Dr. Heil, the availability of different sea ice variables within an application is important in teasing out sea ice conditions. For example, an area of interest could have a 100% sea ice concentration. But by including the sea ice freeboard variable, areas of thicker or thinner ice could be identified.
“We have used this tool to plan a marine-science voyage, and are currently using it to pinpoint deployment locations for autonomous instruments to study ice-edge processes, such as wave-induced ice breakup,” Dr. Heil said. “The tool allows us to look back at the sea-ice concentration and extent over the past few years to gain an understanding of the likely sea-ice conditions in the month of our voyage. We can then identify the most suitable location to take samples and deploy instruments.”
She adds, “The tool also allows us to look at ice conditions in locations where we may have limited or no experience in navigating the ice area, and make decisions about the best time of year to visit to achieve our objective.”
Sean Chua, also a sea ice scientist at AAD, notes that the capabilities offered by NILAS could generate new research ideas or allow scientists to study connections between different components of the Earth system.
The datasets integrated into NILAS were obtained from satellite observations and come from a variety of sources including the National Snow and Ice Data Center, the University of Bremen, the Met Office, and the Ocean Colour Climate Change Initiative.
“In consultation with Antarctic scientists, we chose source data and products that would be the most useful for looking at the long-term climate record,” says sea ice scientist Anton Steketee. “We standardised that data, added some functionality, and presented it on a platform that doesn’t need any technical expertise to use. This tool does not require any software or downloads to run, it can be configured to run without an internet connection, and it displays multiple variables at different time scales.”
According to the development team, the map platform could also be used by students to conceptualize climate variability or provide climate modelers with an easily accessible, visual means to compare model results with actual observations.
The team named their new tool after a stage of sea ice formation: Nilas is the name given to a thin, elastic layer of sea ice that bends slightly in waves and swells and under pressure.
Julia Hager, PolarJournal
Link to NILAS: nilas.org
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