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First
Deployment
April 2000 The North Pole Environmental Observatory is envisioned as consisting of three parts, an automated drifting station, a deep-sea mooring scheduled to begin in 2001, and an airborne hydrographic survey. The deployments are to take place at the North Pole, and the hydrographic survey takes advantage of the deployments to gather data over a wide area around the Pole. The aim for the 2000 operation was to gain experience in the area by deploying the automated drifting station and performing the first hydrographic survey. We anticipate the Observatory will be maintained by yearly operations for five years.
Field party at the North Pole, (l to r) Kiyoshi Hatakeyama (JAMSTEC), James Morison and Dean Stewart (PSC/APL/UW), Sigrid Salo (PMEL), and Trevor Monk (Canadian Met-Ocean Corporation). The deployment team was as small as possible to reduce logistics requirements. Autonomous Buoys and Hydrographic Survey The drifting station plan for 2000 included five buoys. These are: (1) J-CAD - the Japanese Marine Science and Technology Centers (JAMSTEC) J-CAD buoy measuring ocean temperature and salinity at four depths to 250 m, ocean current profiles with an Acoustic Doppler Current Profiler (ADCP), atmospheric temperature and pressure, and wind velocity; (2) PMEL1- the Pacific Marine Environmental Laboratory (PMEL) met-buoy measuring wind speed, atmospheric pressure and temperature, and temperature measured with an experimental aspirated thermometer; (3) PMEL2 - the PMEL radiometer buoy measuring downwelling long- and short-wave irradiance; (4) CRREL1 and
CRREL2
- two Cold Regions Research
and Engineering Laboratory (CRREL) ice mass balance buoys measuring
ice temperature profiles and snow thickness. The hydrographic survey consisted of seven stations between the Pole and our deployment base at Canadian Forces Station (CFS) Alert, Nunavut, Canada. Click on the Station Number to view the temperature and salinity profiles in a separate window.
Chronology Heiberg, Stewart, Hatakeyama, and Monk traveled to Thule, Greenland via the US Air Force Rotator on April 5, 2000. Morison and Salo along with most of the North Pole equipment traveled to Kangerlussuaq, Greenland by New York 109th Air National Guard C-130 on April 10 and then on to Thule on April 13. There Heiberg, Stewart, Hatakeyama, and Monk boarded the same aircraft. The C-130 then transported the North Pole team and equipment to CFS Alert. April 14 and 15 were spent unpacking equipment and making preparations. Two ski-equipped DeHavilland Twin Otter aircraft of First Air Inc. arrived at Alert on April 15 to support the mission. The deployment plan was finalized and the hydrographic sampling pattern was determined. April 16 - One Twin Otter flew to the North Pole, searched for and found the North Pole Environmental Observatory deployment site at 89° 23, 176° 17W. This was near the center of the search area "upstream" of the Pole bounded by 89°N, 150°W, and 150°E. The landing strip was located on a refrozen lead 1.5 m thick surrounded by 2-m ice. The absence of thicker ice on this and our other flights was noteworthy. The other Twin Otter flew with Morison to stock the fuel cache and perform the CTD Station 5 at 85° 57.3N, 68° 38.02W (see table above for planned location). In response to a request by Dr. Preben Gudmandsen of the NPOC in Denmark, during this flight and most subsequent flights we surveyed the ice enroute looking for signs of thin ice and rapid ice production. He has observed evidence of rapid ice production in wintertime satellite imagery just north of Alert. We found that within 30-60 km of Alert, the ice was mainly smooth first-year ice suggesting to Gudmandsen that it is a large area of rapid ice production in the winter. Farther out, what we came to call thin multi-year ice dominated. In general this multi-year ice was relatively free of large, well-weathered ridges typical of very old floes. Most of the ridges were sharp-edged suggesting they had not been through several summer melt seasons. This thin multi-year ice looked to be about 2 m thick like the ice we found for our North Pole Environmental Observatory. The absence of thick old floes may be an aspect of the recent submarine observations that the average ice thickness has decreased from over 3 m to slightly less than 2 m in the last 25 years. April 17 - Two Twin Otters flew to the North Pole Environmental Observatory site with camp equipment. Morison and Stewart erected one building (Hut 1) near the airstrip and were visited by two First Air Twin Otters. One carried a group of tourists, and the other was supporting a National Geographic adventurer, Gus McLeod, flying an open cockpit Stearman biplane to the Pole.
April 18 -
A quick ice thickness survey was done and candidate buoy sites were selected.
The camp area layout at 89¡ 23'N 176¡W is illustrated below. X
indicates ice thickness measurement sites. Hatakeyama arrived with
the remaining camp gear and the J-CAD buoy. The J-CAD buoy was moved to
its deployment site and Hut 2 was erected. The second Twin Otter added
fuel to the fuel cache near 86°N, 70°W.
April 19 Both Twin Otters flew to the Observatory with PMEL and CRREL buoys and Sigrid Salo. The aircraft taxied onto Floe B (above) and offloaded the buoys. CRREL ice temperature buoy #2 was moved to the J-CAD site by sled. Ice holes were drilled and buoy equipment was assembled at both the Floe A and Floe B sites. April 20 Working through a hole next to Hut 1, we performed CTD Station 1A to 1000 m depth at 89° 35.4 N, 162° 16.6W and 1321 UTC. Buoy installation continued. One Twin Otter brought a replacement ice auger out to the site, and the other was released and departed to Resolute. April 21
Working through a hole inside Hut 1, we performed a CTD/bottle Station
to 375 m at 89° 39 N, 148° 24W and
0056 UTC. Water samples were taken at this and the other stations
for Dr. Kelly Falkner
of the North Pole team. A classical approach was taken that minimized
weight and equipment requirements in what must be considered a preliminary
effort. A single Niskin bottle was attached to the CTD cable just above
the CTD. This was tripped with a messenger, and a separate cast was necessary
for each depth sampled. Samples for salinity, barium, oxygen-18, and
nutrients were drawn. The J-CAD installation was completed at 1700Z.
After running successfully for one or two hours the J-CAD stopped receiving
ocean sensor data. We continued installation of PMEL and CRREL
buoys. There were no aircraft operations on this day.
April 22
Working through the hole inside Hut 1, we performed CTD/bottle Stations
to 5 m and 150 m deep at 89° 41 N, 139° 57W
between 0316 and 0355 UTC. A 1000 m CTD cast (1B) was made at 89°
41N, 138° 46W at 1436 UTC. The Twin Otter brought
Trevor Monk to the station about 1600 UTC to aid in debugging the
J-CAD problem. We concluded that unless Monk had an easier solution,
the problem was probably in the underwater connections and the J-CAD buoy
would have to be pulled from the ice to make repairs. Morison departed
on the Twin Otter to complete hydro stations working between Alert and
the Pole. On the way back to Alert we made CTD Station 4 at 87°
29.09N, 90° 51.0W at 2047 UTC. We also deployed AWI
Buoy 8059 at that position in support of the International
Arctic Buoy Program (IABP).
April 23 The Observatory personnel worked on the J-CAD buoy and PMEL and CRREL deployments. They concluded that the J-CAD would have to be removed from the ice. The Twin Otter flew to the station and left Shane Reid, the aircraft engineer, to help with the task of digging out the J-CAD. Morison proceeded to 89° 8.4N 64° 28.5E and performed CTD Station 3 to 1000m at 2013 UTC. This station extended the CTD survey into the Amundsen Basin. The Twin Otter returned to the North Pole Observatory, picked up Reid and returned to Alert. Stewart, Hatekeyama, Salo, and Monk, with Reids help and through prodigious and determined effort, succeeded in cutting a 1.5-m square hole around the J-CAD, and removing the buoy. April 24
The Twin Otter transported Morison and a diagnostic tool for the
J-CAD to CTD Station 2 and the North Pole Observatory. CTD Station
2 was performed to 1000 m at 89°2.6 N, 92° 3W at
1940 UTC. We also deployed AWI
Buoy 8066 at this site in support of the IABP.
The Twin Otter arrived at the Observatory at 2100 UTC to find that
the runway had cracked and the lead between Hut 1 and Hut 2 had opened
slightly. The large refrozen runway lead was open on the north side. While
all this ice activity had been going on, the Hatakeyama and Monk had reassembled
the J-CAD buoy and Salo and Stewart completed the installation
of the PMEL and CRREL buoys. The group then reinstalled
the J-CAD buoy. All the J-CAD sensors reported successfully. Since all
scientific tasks were complete except for one snow survey, the precarious
condition of the runway dictated the camp be evacuated with the highest
priority equipment. All personnel returned to Alert.
April 25
In view of the long effort of all concerned on the previous day, it was
decided to perform only the CTD Station closest to Alert, Station 6. The
CTD station was planned for 900 m depth because the charted dept is only
about 1000 m. At 1742 UTC the CTD hit bottom at 84° 56N,
67° 28.1W and the depth was only 550 m. Dr. Florent
Domine of the Polar
Sunrise group was invited to travel on the flight to perform snow
sampling on sea ice. The Polar
Sunrise program has been going on at Alert for 15 years
in an attempt to determine why, during polar sunrise the marine boundary
layer becomes depleted of ozone. Recent discoveries indicate the photochemistry
of the snow pack is crucial in this. Samples of snow and its structure
far from shore are needed to avoid any nearshore contamination April 26 The Twin Otter flew to the Pole with Salo, Stewart, and the Alert Commanding Officer Major J-P Paris to perform the snow survey and recover the remaining equipment. After two weeks of good flying weather, conditions deteriorated at the end of the day. April 27 There were no air operations while the team waited for the weather to improve. The one remaining task was to do an additional hydrographic station (Station 7) at 86° 40N, 77°W. The reason for this station was that Stations 5 and 6 showed evidence of a well developed Pacific water layer. This suggests a large amount of Pacific water moves around the north end of Greenland. We wished to better resolve the extent of this feature by making one station between stations 4 and 5. April 28 The weather improved slightly at Alert with clearing to the east. The Environment Canada imagery indicated the proposed Station 7 location was near the edge of the cloudy region. Given this relatively encouraging forecast the Twin Otter departed for Station 7. Actual conditions were poor at the proposed site and the Twin Otter had to fly west to 86° 51.0N, 96° 12.3W to find a suitable landing site in good weather conditions. This is farther north and west than we had desired but it will help narrow down the position of the water mass boundary. A 1000-m CTD station was performed at 1645 UTC. April 27 With packing completed the full science party and Twin Otter crew departed Alert and flew to Resolute via Eureka. The science party departed for home via commercial jet from Resolute in the late afternoon. May 24-25
In two flights from Greenland to Alert, the New
York Air National Guard 109th Airlift Wing replaced the fuel used
by the Twin Otters during the deployment. With these flights the 109th
also recovered the project equipment from Alert.
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