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Monitoring Arctic marine conditions AOOS making information about Alaska sea and ice conditions accessible online; proposes helicopter-based sea ice measurements Alan Bailey Petroleum News
Factors such as sea ice conditions, ocean currents and weather are obviously of critical importance to anyone working in the challenging environment of offshore northern Alaska. People such as subsistence hunters or oil and gas explorers need to know as much as possible about offshore conditions and how those conditions may change.
The Alaska Ocean Observing System, or AOOS, a consortium of government, university and private entities, has embarked on a mission to monitor and predict Arctic sea conditions. The organization is developing information products that meet the needs of a broad range of people. And at a workshop in Anchorage, Alaska, oceanographer Mark Johnson from the University of Alaska Fairbanks described some of the AOOS Arctic initiatives.
Improving the models AOOS has made significant progress in making ocean information available but is still in the early stages of developing a complete range of products. For example, the computer models for forecasting sea conditions tend to have too coarse a resolution to provide useful results, Johnson said.
He said that developing high-precision models will take a great deal of effort, involving finer-scale measurements and finer numerical modeling than at present. People want more precise forecasts of nearshore ocean currents, for example.
“This is a real challenge — the numerical (ocean current) models that are run in the Arctic are usually relatively coarse resolution and there’s a real interest in fine-scale resolved currents,” Johnson said.
Models for Arctic ice coverage are also problematic. There are nine different ice coverage models but, when compared with actual observed data, each model works reasonably well in some areas but not in others. Discrepancies in observed ice data from different sources compound these problems.
“We are challenged by having observational data sets that are supposed to give us the same information but are fundamentally different,” Johnson said.
Johnson particularly stressed the importance of validating computer models by obtaining comprehensive data about actual observed conditions. This data collection is such an important issue that current AOOS research is focusing on gathering and making available as much data as possible.
Online data And the AOOS goal is to make this data available online through the Internet.
“Our goal has been to get disparate data sources online, get them available by clicking, by downloading,” Johnson said. “Once that’s done we can move forward in other directions.”
Those data sources are being posted on the AOOS web site at http://ak.aoos.org/.
For example, AOOS has now published online all of the hydrographic data that it can find from sensors around Alaska. Some of this data, including temperature and salinity data, comes from many types of buoys that drift in the ocean or freeze into the ice and beam data to ground stations via satellite.
One practical outcome of collecting this data is an ability to provide the U.S. Coast Guard with information about where people or vessels may drift.
“We’re working with the Coast Guard search and rescue,” Johnson said.
Sea ice data from a radar observatory in Barrow should be online before long, Johnson said. The webcam technology for the radar data is working but the proprietary nature of the data may necessitate password-controlled access, he said.
And once the Barrow radar data becomes available there may be possibilities of operating similar radar stations at other Beaufort Sea coastal sites. There is already a Minerals Management Service-funded HF radar site at Prudhoe Bay for measuring surface currents in the Beaufort Sea.
And Johnson thinks that the online publication of bathymetry datasets will be critical in helping with the computer modeling of ocean systems.
Helicopter sea ice measurements AOOS also proposes to stage a helicopter in Prudhoe Bay for the measurement of offshore ice thicknesses. Using an electromagnetic sensor called an IcePic, mounted on the front of the aircraft, the helicopter would fly transects between Prudhoe Bay and a U.S. Navy offshore ice camp. The IcePic sensor can measure ice thicknesses to an accuracy of about 2.4 inches, while the helicopter flies at its normal cruise speed.
Ice thickness measurements can help with marine safety and navigation, as well as with planning for open water activities, Johnson said.
“We think this will be useful for the coastal residents in Barrow and perhaps the oil and gas (industry) in Prudhoe, because if you know how thick the ice is you know how early your season will end or how soon the water might open up,” Johnson said.
Scientific research would probably entail flying the helicopter three or four times a year to obtain seasonal information — researchers could, for example, relate the ice thickness information to ice strain and stress measurements made offshore Prudhoe Bay.
“(For oil and gas interest) I would think you would want to fly this in March or April, right before breakup when things start moving around,” Johnson said.
AOOS has approached both the National Aeronautics and Space Administration and the National Science Foundation for funding of the helicopter program. Johnson said that he is also talking to private companies about sponsoring some of the costs of the program — sponsors would have a strong influence over where the measurements are made and would have rapid access to the data, he said.
Traditional knowledge Regardless of all the scientific data that AOOS is assembling, Johnson sees the traditional knowledge of the North Slope residents as critical to the understanding and forecasting of offshore conditions — traditional knowledge needs to be blended with the scientific data.
For example, the Native people tend to recount extreme conditions such as especially low or high temperatures. And that oral history can validate statistical outliers in the data that science would otherwise discount.
“It’s precisely those outliers that are recorded in their oral tradition,” Johnson said.
And the researchers are anxious to ensure that the AOOS information products meet the needs of the Arctic coastal residents. Johnson said that a team from AOOS met in February with the Alaska Whaling Commission and local residents in Barrow. That meeting identified the value, for example, of tracking large ice floes offshore Barrow, using a combination of direct observation and tracking from satellites.
“In the summertime it’s nice to know where these large floes are, if they’re beyond the visual horizon,” Johnson said. “They serve as a place for rescue … they also serve as a place to pull the whales out during the hunting season.”
The North Slope residents are also interested in the monitoring of background noise in the ocean, especially with the amount of oil and gas activity going on in the region. A ship watch program to monitor shipping movements is another possibility.
And one outcome of the Barrow meeting was an initiative to provide synthetic aperture radar imagery (known as SAR imagery) for a coastal strip from the Bering Strait all the way around northern Alaska and northwestern Canada to the Mackenzie River. SAR provides high-resolution imagery of surface features; the technology can operate through cloud cover and after dark.
“I have submitted a proposal to NASA to do this.” Johnson said. “The word is that they like the idea, and if NASA approves the proposal, they will help us work with the Canadian Space Agency … to see if we can display this commercial product for subsistence users … This may become real in the fall, or certainly by spring ‘07 if approved.”
Seeking other ideas The Barrow meeting was part of a process in which AOOS is seeking the information needs of all people and businesses with an interest in the Alaska Arctic offshore environment. AOOS welcomes requests and ideas for information products.
“Please talk to us, talk to me and let me know and we’ll see if we can get it online and make it available,” Johnson said.
And Johnson likens the current status of the AOOS programs to the status of the National Weather Service a decade or two ago.
“It will be … interesting to see where we are in five and 10 years,” he said. “Better marine forecasts help in so many ways and I am excited to be part of this work.”
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