Mapping Icebergs with Technology Pioneered at LOOKNorth
When it comes to dodging icebergs in frigid northern waters, advance information is key; knowing where they are, how big they are and where they’re going.
The latest technology to map these floating ice giants is the Altimeter Iceberg Detector (AID), developed in St. John’s NL through LOOKNorth (Leading Operational Observations and Knowledge for the North), an initiative of C-CORE headquartered at Memorial University.
This system was the brainchild of Dr. Igor Zakharov, a senior research scientist and engineer at LOOKNorth. In the fall of 2011, with support from C-CORE’s Remote Sensing team, Dr. Zakharov began developing algorithms and data processing methods to detect iceberg signatures (differentiating icebergs from background noise) and to analyse data (eliminating false detections) for reliable output of results. Within a month, the Altimeter Iceberg Detector (AID) was born.
The altimeter is a radar satellite, which measures the height of the sea surface and detects anomalies by transmitting and receiving pulses directed straight down. Altimeter data are widely used to model ocean circulation and to record and monitor sea level and climate changes over time. “AID is basically a software that contains a series of algorithms,” says Dr. Zakharov. “Those algorithms process a continuous stream altimeter data, analyse it, and produce an output map with coordinates of detected icebergs.”
This data is free, compared to a cost of $5,000 per image (500 sq. km.) for Synthetic Aperture Radar (SAR) data. “Cost is definitely another advantage of AID,” says LOOKNorth Executive Director Paul Adlakha. Using AID is about 10 to 15 per cent of the cost of using SAR data and large areas can be monitored quickly and inexpensively. This is especially valuable for frontier areas where there is a large coverage area, little infrastructure but satellite coverage is available.
However, both methods are ideally used in combination because altimeters provide a cost-effective wide-area view and can detect large ice masses within that; AID detections can be used to direct where the more expensive, but higher-resolution SAR imagery should to be captured, yielding detections of smaller ice masses and differentiation between an iceberg and a ship. Detail is enhanced by using the two methods. “C-CORE has been around for 37 years and we have many years of experience and expertise in iceberg and sea ice monitoring using radar satellites,” explains Paul. “We were focusing our research and development strategy in three areas – monitoring icebergs, monitoring oil spills and terrain stability, when Dr. Zakharov came up with the idea of using satellites for iceberg detection in this way. Because of our strong history in this area and the fact that he’s brilliant, it came together quite quickly.”
The technology was very quickly commercialised and interestingly, the first time it was used for a yacht race. “During the Volvo Ocean Race between the end of December 2011 and beginning of March 2012, we were asked to provide iceberg locations to the participating yachts,” says Dr. Zakharov. Some 8,000 icebergs were detected; 80 to 90 per cent of the work involved the use of altimeter data, which was then confirmed and further delineated with SAR (satellite-based synthetic aperture radar). “When yachts race around the world, the closer they are to the North or South Pole, the more they can shave off their time, but it’s risky because of the icebergs,” he explains.
There are more practical applications for this technology. “There’s the obvious safety factor for sea-faring traffic,” states Adlakha. “And cruise ships that advertise iceberg sightings can use it for their tourism traffic. But it can also be used to plan offshore structures if you use historical data so that you can project what kind of platform you need to build and the viability of the location.”
Dr. Zakharov envisions further improvements to the technology: “Altimeter radar has now been proven to detect large-scale sea surface anomalies - large ice masses- clusters or individual icebergs of 150-200 meters across. More work on defining iceberg parameters could potentially enable altimeter detection of smaller ice masses that can pose threats to shipping and other marine activities in ice-prone regions.”
Support from Industry Canada was critical to the development of AID. “The core funding we received through the Centres of Excellence program was the whole reason for LOOKNorth’s existence,” says Adlakha. “Along with our other funders, Industry Canada support is crucial to the work we do. It helps leverage other funding and gets the whole thing pulled together. We wouldn’t be here without it.”
In 2013 C-CORE was contracted to characterize the ice regime in an area of the South Atlantic Ocean (approximately 51°S latitude, approaching the Antarctic) newly under consideration for hydrocarbon development. AID analysis yielded many detections, from which C-CORE produced an initial 20-year time series of ice populations within the regions.
Work is ongoing to improve ship/iceberg discrimination in AID and to compare AID detections against C-CORE’s extensive in-house historical SAR datasets. The aim is to reliably extrapolate iceberg population within an area of interest from an AID point detection.