Archive for the ‘Fairweather’ Category
From surveying our most northern Alaskan waters last year, to our southern coastal waters this year, NOAA Ship Fairweather has really been making the hydrographic rounds, so to speak. This month, Fairweather’s hydrographic work is reaping benefits for the maritime industry in Los Angeles and Long Beach.
Fairweather is surveying this area in response to requests from the Port of Los Angeles, the Port of Long Beach, and the pilots who maneuver increasing large oil tankers and cargo ships through the area’s crowded shipping lanes. This project will acquire data for comprehensive updates to NOAA nautical charts 18749 and 18751, which provide the depth measurements and aids to navigation that mariners rely on for safe transit. Fairweather last surveyed the area in 1975, and NOAA contracted for a small survey in 2000.
This chart shows where NOAA Ship Fairweather is surveying.
This project undertakes surveys encompassing 114 square nautical miles. Of those, NOAA considers 89 SNM as critical to safe navigation and therefore a NOAA priority. The survey areas include San Pedro Bay and its approaches, stretching south to the waters off Huntington Beach and Newport Beach.
Capt. Kip Louttit, executive director of the Marine Exchange of Southern California San Pedro, presents a certificate of appreciation to Fairweather‘s commanding officer, Cmdr. James Crocker. Photo credit: Capt. Kip Louttit
Retired Coast Guard captain J. Kip Louttit, executive director of the Marine Exchange of Southern California San Pedro, visited the ship last week to thank the “great ship and crew [for] doing an incredibly necessary survey for the ports.”
The Fairweather usually operates in Alaskan coastal waters and, last year, conducted a noteworthy hydrographic reconnaissance along the U.S. coast in Arctic waters to determine the priorities for updating Arctic charts. Fairweather is part of the NOAA fleet of ships and aircraft operated, managed, and maintained by NOAA’s Office of Marine and Aviation Operations, which includes both civilians and the commissioned officers of the NOAA Corps, one of the seven uniformed services of the United States. The ship is homeported in Ketchikan, Alaska.
NOAA Office of Coast Survey has released a new nautical chart for the Arctic, which will help mariners navigate the Bering Strait. Chart 16190 (Bering Strait North) incorporates precise depth measurements acquired recently by NOAA Ship Fairweather hydrographic surveys.
Coast Survey has also released a new edition of Chart 16220 (St Lawrence Island to Bering Strait).
“Our Arctic Nautical Charting Plan identified the need for 14 new charts in the Arctic,” explains Commander Shep Smith, chief of Coast Survey’s Marine Chart Division. “Chart 16190 was high on our list of priorities, since the Bering Strait is the maritime gateway from the Bering Sea in the Pacific Ocean to the Chukchi Sea in the Arctic Ocean.”
“Charting the gateway is absolutely vital for safe navigation, but it is more than that,” Smith says. “In addition to the very practical aspects, this chart also symbolizes an opening to the growing opportunities for maritime transportation in the Arctic.”
Charts 16190 and 16220 include recent hydrographic information in U.S. waters between Cape Prince of Wales and the immediate waters surrounding Little Diomede Island. They also include recent NOAA shoreline surveys of the Diomede Islands and Cape Prince of Wales.
NOAA Chart 16190, Bering Strait North
Chart 16190 provides 1:100,000 scale coverage, including a 1:40,000 scale inset of Little Diomede Island. Chart 16220 provides 1:315,350 scale coverage. Prior to these charts, the best available information was from Chart 16005, at a scale of 1:700,000. At that scale, every charted depth was separated by about two nautical miles and the chart depicted only a handful of depths. Most of the old charted depths were from 1950 and provided incomplete information about the depths or possible hazards on the sea floor.
Chart 16190 is the second new chart resulting from the Arctic Nautical Charting Plan. Coast Survey created the first of the new Arctic charts, Chart 16161 (Kotzebue and Approaches), in April 2012. (See New Alaska navigational chart makes increased Arctic shipping safer.) Chart 16220 had previously been maintained by the National Geospatial-Intelligence Agency, but Coast Survey assumed responsibility for it in 2010.
The equivalent NOAA electronic navigational charts (NOAA ENC®) for 16190 will be available this summer. Watch for US4AK8D (Bering Strait North), and US5AK8D (Little Diomede Island). The 16220 ENC equivalent — US3AK89M — was created in 2012 and included the new Fairweather hydro.
Coast Survey’s Marine Chart Division is responsible for updating the nation’s 1,023 nautical charts. Chart 16190 was compiled by Kieumy Dinh and reviewed by Eric Wallner, under the management of Andew Kampia. Chart 16220 was updated by Pravin Shrestha (compiler) and Yan Xu (reviewer).
Today’s post is written by a guest blogger, Dr. Bob McConnaughey. Bob is the FISHPAC project chief scientist, with NOAA’s Alaska Fisheries Science Center.
Fishery biologists and hydrographers in NOAA are working together to solve two very important problems in the eastern Bering Sea. This area is one of the richest and most productive fishing grounds in the world. Careful management of harvest levels is one part of the effort to sustain these populations into the future. However, it is also important to understand the habitat requirements of the managed species so we can protect the foundation for these high levels of production.
To this end, a team of scientists at the Alaska Fisheries Science Center (AFSC) is developing mathematical models to explain the distribution and abundance of groundfish, such as pollock and cod, and benthic invertebrates, such as red king crab, in order to determine their essential habitats. The research team gathers new environmental data at locations where other AFSC scientists sample fish populations during annual bottom-trawl surveys. In many cases, existing habitat information is very limited, but studies will identify useful variables and the best tools for measuring them over large areas of the continental shelf.
NOAA hydrographers working in Alaska are likewise challenged by the sheer size of the offshore areas and the dearth of recent depth measurements. This region includes over 47,000 miles of coastline and roughly 70% of the nation’s continental shelf. Soundings data for nautical charts are usually quite old and coverage is incomplete. Similar to the habitat studies, there is a great need to gather new data, efficiently and cost-effectively.
A diverse team of NOAA personnel and external partners are collaborating to address the critical need for new habitat data and new hydrographic data from the eastern Bering Sea. Beginning in 2006, NOAA Ship Fairweather has conducted multi-mission cruises to simultaneously achieve these two objectives. The so-called FISHPAC project has developed procedures to collect acoustic backscatter data to characterize seafloor habitats while also collecting high-quality bathymetric data for updating nautical charts.
This joint effort has been a great challenge for two groups that have typically worked alone, generally focusing on a single specialized activity. The successful integration of these activities makes efficient use of valuable ship time and will ultimately increase the amount of data collected for both purposes in a single survey season.
The prototype long-range side scan sonar is prepared for deployment. An emergency locator beacon is activated to help locate the towfish if it becomes detached from the double armored tow cable.
The AFSC scientists have introduced new types of equipment on Fairweather for this work, including a prototype side scan sonar capable of very broad coverage (up to 1 km) at a fast tow speed (up to 12 kts), an acoustic underwater tracking system that provides accurate positions for towed instruments, and several “groundtruthing” instruments to help interpret the backscatter data for habitat purposes. The partners have worked out safety and deployment details, and now the ship can simultaneously acquire acoustic data from the ship’s two multibeam echosounders and a towed side scan sonar, while underway and collecting sound velocity profiles and geotechnical data from the seafloor with a free-fall cone penetrometer! Operating this way, the ship does not need to stop; they can conduct survey operations around the clock during the entire time at sea.
Fairweather hosted a major FISHPAC cruise during July-August 2012. A team of 12 scientists joined the Fairweather’s standard crew of officers, physical scientists and seamen to conduct a combined fish-habitat and hydrographic-survey effort in the eastern Bering Sea. The group worked together ‒ night and day ‒ to acquire the multi-purpose data. They tested five different sonar systems in an experiment designed to identify the most cost-effective system for characterizing the seafloor and improving the existing fish-habitat models. At the same time, the ship collected over 1,000 nautical miles of hydrographic data in an area with outdated or non-existent information.
Technicians from the Naval Undersea Warfare Center (Keyport, Washington) and a retired NOAA engineer and hydrographer provided valuable assistance.
Neither high seas, nor fatigue, nor equipment problems stopped the intrepid group. The project was fully successful in the end and Fairweather safely returned to port in Dutch Harbor, Alaska to discharge some scientists and then head back out on her Arctic Reconnaissance voyage.
The towed auto-compensating optical system (TACOS) is a two-part towed video system consisting of a weight sled connected to the ship’s fiber optic winch, with a camera sled trailing approximately 20 meters behind the weight sled. The camera sled includes an analog video camera, a digital video camera, six high intensity discharge lights as well as an acoustic release/buoy for emergency recovery. TACOS creates high-quality downward-looking video mosaics.
This week the NOAA Ship Fairweather is completing her 30-day hydrographic reconnaissance survey in the Arctic. The crew’s personal observations during this successful cruise brings home the importance of measuring ocean depths and updating nautical charts with precise and accurate modern data. Ensign Owen provides Fairweather’s last blog post for this project. - DF
by Ensign Hadley Owen, NOAA, Junior Officer, NOAA Ship Fairweather (S-220)
1200 hours, Sunday, August 26, 2012:55°57.2’N 166°01.2’W, Bering Sea, approximately 100 nautical miles north of Unimak Pass
We are back in the Bering Sea, sloshing around amongst multiple low pressure systems on our way back south to finish out the Fairweather’s 30-day Arctic recon. While it has appeared a lonely transit at times, our AIS (Automatic Identification System) has proved that there are others along this Bering/Chukchi/Beaufort Seas route who will benefit from the updated hydrographic data we are recording.
We have seen more than 50 vessels over the past few weeks, including tugs and towing vessels; cargo ships; fishing vessels; tankers; research ships; U.S Navy and U.S. Coast Guard vessels; and even a couple of small passenger vessels. The ships have ranged from 12 meters to over 200 meters, with drafts of up to 15 meters.
We met mariners with a boat – essential to the region’s economy – whose crew has had frustrations with inaccurate charted soundings. The Greta Akpik is a lightering vessel operated by Bowhead Transport Company. The Fairweather stopped mid-trip outside of Barrow in order to disembark three scientists who were returning home, as well as to pick up stores to provide the remaining crew with food and supplies for the second half of our trip. As the town of Barrow does not have pier facilities, residents depend on the services of shallow-draft lightering vessels to transfer supplies between ships and shore. In casual conversation, the crew of the Greta reported soundings on a chart marked at 30 feet which in actuality read 5 feet on their depth-sounder – a somewhat nerve-wracking discrepancy but not impossible for their shallow-draft vessel. However, this kind of variation can prove a significant deterrent to other maritime traffic looking to enter the region.
Two examples of this “other” traffic that we encountered near Barrow were the 194-passenger Hanseatic and the 165-stateroom The World. Both vessels are considered luxury expedition cruise ships, offering their patrons unique opportunities to visit the world’s last remote outposts. The Hanseatic was on a 27-day trip from Nome, Alaska, to Reykjavik, Iceland. The World is a “privately-owned, residential yacht” for 130 families who collectively chose their vessel’s annual destinations. Both were traveling along the North Slope of Alaska, preparing to transit the Northwest Passage en route to the Atlantic Ocean. In addition to bringing a modest level of tourism to the area, these expedition cruise ships also serve to increase the world’s awareness of the rarity of these remote Arctic Alaskan communities. They mark the beginning of increased and wider interest in the accessibility of the area and the ease with which services can be obtained.
Even with this level of traffic, we are quickly reminded of how much the area’s nautical charts need to be updated, as we transit across a 28 nautical mile square region, south of St Lawrence Island in the Bering — which is totally lacking in soundings. To date, vessels have operated safely by relying on a great degree of local knowledge and nautical good sense. Our recent transit, however, has not only emphasized the degree to which our charts of the area need to be updated, but reminded us of the range of traffic that will benefit from these corrections and additions.
by Ensign Hadley Owen, NOAA, Junior Officer, NOAA Ship Fairweather (S-220)
1200 hours, Saturday, August 18, 2012: 69°41.4’N 141°03.3’W, at anchor, 1.5 nautical miles west of Demarcation Point, on the United States/Canadian border
We made it!
Photo by Caryn Zacharias, LT/NOAA
I must admit, I had my doubts a week ago. But we made it safely through relatively ice-free seas to the northern border between Alaska and Canada’s Yukon Territory.
We were able to collect multibeam echo sounder data along the entire route. The area continues to be relatively shallow (8 to 25 meters) and relatively flat (1 to 1.5 meters of relief). However, dramatic ice scours and scars on the seafloor are easily visible in the data collected.
This “pseudo-side-scan” image – which looks at only a preliminary selection of the initial acoustic data recorded – was obtained in real time.
Image by Chief Survey Tech Tami Beduhn, NOAA Ship Fairweather
We are now surveying from both the Fairweather and from one of her launches (during the day, at least). By using both platforms, we are able to obtain even more soundings on our return track to Barrow and send the launch into shallower, near-shore areas.
But this update cannot be complete, I feel, without a personal first. Thanks to the eagle eyes from the Bridge, we had the first of two polar bear sightings from the Fairweather – this one a mother and her two cubs.
Photo by Casey Marwine, ENS/NOAA
And now we are heading west.
by Ensign Hadley Owen, NOAA, Junior Officer, NOAA Ship Fairweather (S-220)
1200 hours, August 17, 2012: 70°13.7’N 144°49.6’W, approximately 250 nautical miles along the coast SSE of Barrow, AK
The water turned a silty gray-green early afternoon yesterday, Thursday, August 16. The Fairweather was transiting through areas with depths under our keel of between 8 and 20 meters – a somewhat caution-inducing sight for a vessel of our size. But the ice has opened up and we have made it east of Barrow. We are currently the furthest east along the North Slope of any NOAA or U.S. Coast and Geodetic Survey hydrographic ship, as previous surveys were last conducted by field parties with much smaller boats, in the 1950s and 1960s. As the crow flies, we are currently 90 miles or so west of the Canadian border and our turn-around point. However, we are of course not transiting in a straight line but in the zigzag/argyle pattern, so have a bit more sea floor to cover.
For a normal hydrographic survey, we use the Fairweather and her launches to drive over an area slowly and methodically with set parallel line spacing. With the multibeam echo-sounders, we are able to record data for a swath of between five and seven times the depth in which we are surveying. The survey lines are spaced to have a minimum of 25% overlap and thus comprehensive coverage of an area as well as moderate redundancy to ensure accuracy of the data collected.
As this Arctic trip is a “reconnaissance” survey, we are using the argyle pattern to cover as much area as possible while still ensuring quality of data via some overlap of tracklines. The image below provides a good visual. This pattern allows us to evaluate the data on the charts though varying depths. The blue lines represent one year (out and back) and the red the next year (out and back again). By crossing over previously surveyed lines – both within one season’s trip to the border and back, and potentially from one year to the next – we can both verify the data from the prior acquisition and help determine where there might be relatively rapid changes in the bottom characteristics (due to strong currents and a soft bottom, for instance).
Our current trackline has been modified yet again. Due to the ice, instead of surveying an area between 5 nautical miles (nm) and 60 nm out from shore, we have compressed our accordion to range between 1.5 nm and 30 nm out. From our observations, looking at aerial images of the sea ice, and listening in on radio traffic between the limited vessels transiting the area, it is looking promising that we will make it to Demarkation Point, on the Canadian border.
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We weren’t feeling so optimistic a week ago.
A combination of heavy fog and ice fields unexpectedly far south made data acquisition – bottom samples and CTD casts (measuring conductivity, temperature, and depth) – impossible at our scientists’ scheduled sample sites, and required deviation from the intended survey route. However, our plans on the Fairweather continued to adapt to the developing conditions, and not only were we able to satisfy our scientists research needs, but we also were able to experience some pretty cool Arctic phenomena. Oh, and squeeze in a little extra surveying just outside of the town of Barrow – in order to provide “ground truth” data to support a study on the feasibility of satellite-derived bathymetry to update nautical charts.
This past week, however, is best told in pictures taken this Arctic trip by NOAA Ship Fairweather crewmembers.
Our first sight of ice on the Fairweather, August 10, 2012 (71°14’N 160°56’W), through the eye of the ship’s alidade. Photo by Tim Smith, LT/NOAA
While waiting for the ice and fog to clear sufficiently for the Fairweather to continue its mission, the crew all took part in a “reconnaissance” by small boat along the ice edge. Photo by Grant Froelich, NOAA
Photo by Brian Glunz, NOAA
Photo by Scott Broo, ENS/NOAA
We all felt a little bad for the folks who had to wait until the end of the day to go explore the ice in the launch. Until they came back with pictures of walruses.
Photo by Tim Smith, LT/NOAA
A couple of days later, there was a hurried call on the radio from the bridge to survey, requesting that they pull in their MVP (moving vessel sound speed profiler) “fish” being towed behind the Fairweather – we were approaching a large field of ice and needed to be prepared to maneuver. However, the ice never got any closer. It turned out to be an example of Fata Morgana – an Arctic mirage, caused by the refraction of light rays due to the cold and dense polar air. Photo by Shauna Glasser, NOAA
Viewed through binoculars, our very own “ghost ship.” This ship was actually 23 miles away at the time – over the visible horizon. Photo by Scott Broo, ENS/NOAA
Another phantom vessel – this one only six miles away, but appearing much closer. Photo by Casey Marwine, ENS/NOAA
A little bit of everything – ice, midnight sunsets, and some Arctic special effects. Photo by Scott Broo, ENS/NOAA
Good news! When NOAA Ship Fairweather started her Arctic reconnaissance survey, on August 1, there was some question about whether she would be able to complete the entire trackline. The icepack from Barrow to the Canadian border had not yet receded. Thanks to satellite imagery and ice forecasts, we can see open water up to Barter Island, and then thin ice to Demarcation Point. Cmdr. Jim Crocker is now able to follow a nearshore route. They will survey closer to shore than the planned transit route – and acquire very useful hydrographic data!
We can’t wait to get the next blog update directly from the Fairweather…
(For background, see NOAA Ship Fairweather conducting hydrographic reconnaissance survey of the Arctic.)
by Ensign Hadley Owen, NOAA, Junior Officer, NOAA Ship Fairweather (S-220)
1200 hours, August 12, 2012: 70°38.7’N 162°06.6’W, approximately 22 miles north of Icy Cape, Alaska’s North Slope
In 1963, the town of Point Hope (68° 21’N 166°46’W) – a small, ancient, and archeologically-significant Inupiaq community on Alaska’s North Slope that remains at present a largely native village – narrowly avoided the creation of an artificial harbor by underwater hydrogen bombs. Part of “Project Plowshare,” the planned creation of a deepwater harbor by thermonuclear power was intended to demonstrate the peaceful use of nuclear power for construction purposes. It was opposed by Native American communities, scientists in the state, and the Episcopalian church across the United States. The protest has been credited as one of the first government projects successfully challenged on the grounds of its potential environmental impact.
Point Hope is just one example of an Arctic Alaskan community for which an increased understanding of the regions oceans and near-coastal areas will prove relevant. From the bathymetry of the coastal region, to the chemical composition of its waters, and the characteristics of its benthic community, studies will document changes in the region due to increased exposure and vessel traffic. The NOAA Ship Fairweather’s current Arctic reconnaissance trip continues to offer that rare opportunity in environmental science – the establishment of “baseline” characteristics of a largely untouched region from which to monitor potentially imminent changes.
In 2008, the USCG Cutter Spar conducted a preliminary hydrographic survey around Point Hope (and other areas), which determined that strong currents in the area were contributing to large shifts in the coastal bathymetry (underwater topography). Sandy sediment and shallow depths, as well as the high level of coastal erosion, have resulted in a significantly changeable nature of the region’s seafloor. Point Hope was one area of interest for this summer’s investigation; on August 8, our ship-based reconnaissance survey of the spit of land’s projection into the ocean showed differences from the area’s charted depiction.
While NOAA’s Office of Coast Survey interest in updating our hydrographic understanding of this region of the Arctic has driven this voyage, we were happy to welcome in Kotzebue a trio of scientists whose work overlapped with and supplemented our own mission. Dr. Doug Dasher, an environmental scientist at the University of Alaska Fairbanks, has had an ongoing interest in Point Hope and related environmental radioactivity studies. He and Terri Lomax, from the Alaska Department of Environmental Conservation, are on board as part of a large-scale survey of biological and chemical trends in the waters of the Arctic Chukchi Sea. Under the Alaska Monitoring and Assessment Program (AKMAP), they are using a stratified random sampling plan over a large area to get the “big picture” of a marine area’s health. Their work supports the U.S. Environmental Protection Agency in their national Aquatic Resource Survey of the nation’s waters.
Also onboard is an aquatic toxicologist from NOAA’s National Center for Coastal Ocean Science (NCCOS), Dr. Ian Hartwell. His path crossed with Dr. Dasher’s several years back in Kachemak Bay on Alaska’s Kenai Peninsula (south of Anchorage), where they were both conducting similar research to their present study. Dr. Hartwell’s work is part of NCCOS’ Coastal Ocean Assessment, Status and Trends (COAST) Program, which conducts biological, physical, and chemical assessments of habitats affected – or potentially affected – by contaminants.
Together, they are paying particular interest to a 25 to 30 nautical mile corridor offshore in the Chukchi Sea. The corridor stretches between the Arctic Ocean’s deep-water oil leases, currently being researched and developed by international oil companies, and the largely subsistence native communities of Alaska’s North Slope. The forward-looking exploration of our Fairweather cruise meshes well with AKMAP’s and NCCOS’s goals of defining and describing the relatively untouched environment of the coastal North Slope. In light of increasing maritime traffic, AKMAP and NCCOS hope to monitor potential contamination and help to proactively address future environmental impact upon this still largely untouched Arctic region.
Before we get to the Fairweather logs, we need to update the last post, NOAA Ship Fairweather zigzags her way to accurate and precised depth soundings. Cmdr. Crocker reports that the “normal” zigzagging won’t start until they head further north, starting near Point Hope. It was not planned for the trip to Kotzebue, and he would have run a straight course if he could have. This log by Ensign Hadley Owen explains why they zigzagged earlier than planned, as well as what they are doing for their first scientific project. We apologize for the error in the last post. -DF
Fairweather Log Entries, August 2 and August 5
by Ensign Hadley Owen, NOAA, Junior Officer, NOAA Ship Fairweather (S-220)
2400 hours, Thursday, August 02, 2012: 57°04.9’N 167°05.5’W, underway, Dutch Harbor to Kotzebue Sound
We left Dutch Harbor on the NOAA Ship Fairweather on August 1, to begin our 30-day reconnaissance trip bound for the Arctic. Our departure had been delayed until 1800 on Wednesday in order to let pass a 988 MB low-pressure system moving northeast through the Aleutians. Our initial plan was a straight line running generally west by north, on which we would acquire seafloor data using the ship’s hull-mounted multibeam echo sounder and a towed Klein 7180 long-range side scan sonar (a one-of-a-kind device designed to maximize the effectiveness of broad-scale fish habitat studies using acoustic “backscatter”). However, a persistent 8’ swell on the ship’s beam resulted in a more than 20-degree roll that kept many crewmembers in their beds and made useful data acquisition nearly impossible. Cmdr. James Crocker, commanding officer of the Fairweather, made the call to alter course in order to pass over the acquisition stations in a tacking motion – zigzagging our way north in order to minimize the effects of the swell on our ship’s data collection activities.
The first leg of our Arctic cruise is focusing on work conducted for NOAA’s National Marine Fisheries Service, and led on the Fairweather by Dr. Bob McConnaughey. He and his team of NOAA scientists and Navy technicians have been studying and mapping benthic regions in the eastern Bering Sea since 1996, addressing a congressional mandate to understand the habitat requirements of the nation’s managed fish and crab populations. Their recent work has focused on using a variety of sonars to identify seafloor properties that affect the distribution and abundance of fish, including the Fairweather’s multibeam echosounders (traditionally used for hydrographic surveying) and side scan sonars that can continuously survey a swath of seafloor up to a kilometer-wide, at a maximum speed of 12 knots. The project goal is to measure backscatter from the ocean’s bottom, rather than to simply produce images of it, and to use this information in combination with other environmental data and estimates of fish abundance from annual bottom trawl surveys to improve the team’s mathematical models that identify the habitat requirements of individual species. At the same time, we are taking care to produce hydrographic-quality bathymetric data for updating nautical charts in areas with outdated or non-existent information – a great example of NOAA’s integrated ocean and coastal mapping strategy.
The NOAA team onboard Fairweather during the NMFS fish research project
The NMFS team’s broader interest in the Fairweather’s reconnaissance mission is to be at the forefront of activity documenting the areas that are opening up as the region’s ice-cover retreats. By this work, NOAA’s intention is to be well prepared to support fishery management decisions related to emerging uses: commercial fishing, large-scale shipping and navigation, and oil exploration interests. The team aims to document similarities and differences in the seafloor habitats found along the more than 1,000 km reconnaissance line extending from Dutch Harbor in the Aleutian Islands to the Kotzebue Sound area above the Arctic Circle. The data collected from the eastern Bering Sea, the northern Bering Sea and the Chukchi Sea will provide insights about possible outcomes if fish populations redistribute northward due to environmental change. It will also help us to understand the susceptibility of these areas to new forms of human disturbances.
Fairweather deploys the Klein side scan sonar
As of the end of Thursday, August 2, the seas have settled down and allowed the Fairweather to deploy the long-range side scan sonar and begin acquiring data. Depending on conditions, the sonar’s towfish will remain in the water until the northern end of the survey line near Kotzebue. In addition to backscatter data, the side scan sonar is also acquiring data about water column properties such as chlorophyll.
We are keeping a close eye on ice conditions for the latter part of our route. The current ice edge runs to Barrow, and will at present prevent us from completing the last leg of our track in the Beaufort Sea – along the north coast of Alaska and east to the Canadian border. However, any data obtained during this reconnaissance mission will initiate a new large-scale systematic study of the region’s benthic habitats, will provide new bathymetric data for nautical charts, and will ultimately create a foundation for appropriate management and safe navigation in the region’s future.
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1800 hours, Sunday, August 5, 2012: 67°00.8’N 165°35.5’W, heading east, Kotzebue Sound, north of the Arctic Circle
We have been transiting increasingly shallow water since we passed Nunivak Island. As the Klein 7180 operates best in depths greater than 20 fathoms, we were able to take advantage of improved weather and relatively calmer seas to bring the towfish on board yesterday morning. However, data acquisition continues with the ship’s multibeam echo sounder.
At 1400 hours we crossed the Arctic Circle (66°33’N), heading northeast towards the town of Kotzebue. Dr. Bob and his crew will disembark the Fairweather early Monday morning and we will shift focus with a new team of scientists as we continue north. As we transit to our anchorage near the head of the Sound this evening, we will navigate using the newest chart (16161) of the area. NOAA produced Chart #16161 in May, using survey work conducted on the Fairweather last summer; it will be an inspiration for the work to come.