This report is combined for two days because the events associated with the Palmer assisting the Gould took place during the two-day period. We are currently (0036, 15 August) steaming to station #52, the next one on the broad-scale survey grid to be sampled and expect to arrive there later in the morning. Our position now is -67° 25.914S; -70° 21.572W. Winds are light at 10 kts out of the east (094), but the barometer is still low at 954.1. Air temperature is -20.3°C.
On 13 August, we completed the work at station #51 about 0200 and then broke off the survey to assist the R/V L.M. Gould get free of the pack ice that they were stuck in. We had planned to meet the Gould at a rendezvous point midway between stations #42 and 52 about 0800 on 13 August, but the Gould had been unable to move from the location of their last station. Just after getting underway on a northeasterly course from station #51, there was enough snow to cause a white out and force the Palmer to stop and wait until visibility improved. Winds were from the north in the 40 knot range and there were gusts up in the 50's. The temperatures, which had been around -5°C, fell precipitously during the morning hours to down about -20°C by noon. But the skies cleared and we traveled through the pack ice strewn with an amazing and majestic series of icebergs. By 1245, the Gould was in sight and by 1432, it was following us back down the trackline that we came in on. Their plan was to work south of Adelaide and into the Laubeuf Fjord area and then head up the west side of Adelaide Island and make another ice camp. Late in the afternoon the procession stopped in an area with open leads and a transfer of equipment and a person was done prior to the vessels parting ways.
The Palmer got under way for station #52 about 1600 with snow falling heavily at times. The Gould, however, had difficulty carrying out its plan and by about 1930 we received a call requesting additional assistance getting to a place where they might have a chance of getting to work sites and then to Palmer Station on its own. Since leaving them, the Gould reported that they had only managed to go 2 nm. We turned around steamed about 3 hours to their location. During the steam, the snowfall increased and the barometer dropped down to the lowest point in the cruise 946.5 mlb and was still falling. The air temperature rose some to -11.8°C and the wind was out of the southeast (122) at 30 kts. The snow was horizontal across the decks. By 2315 when we had arrived next to the Gould, the barometer had fallen to 939 mlb and the wind speed had risen to between 30 and 40 kts out of the southeast. It was a raging blizzard and the barometer was still falling. White-out conditions made it impossible to move and so both vessels were hove to in the ice pack waiting for the storm to abate.
Neither ship moved all night because of the zero visibility from the high winds and blowing snow. There was no way the Gould could have followed the Palmer, even if it could have steamed along a course line, and there was no steaming with zero visibility in these iceberg-filled seas. The barometric pressure got down to 935 mlb about 0100 on the 14th of August before coming up again and the winds were in the 40 knot range with gusts into the high 50's for most of the late night. The snow ended around 0800 and skies began clearing, the wind speed dropped into the low 20's and shifted to being out of the north northwest (299). The temperature plummeted to the lowest point on the cruise thus far, -24.8°C, and the barometer was rising (955.8 mlb). With improved visibility, the procession was again started, this time to the north toward broad-scale station #19, a location where the Gould might be able to operate on its own.
During the morning of the 14th, the scientific party on the Palmer held a meeting to discuss alterations to the survey plan given the possibility that additional assistance might be required by the Gould to leave the survey area and make its way to Palmer Station. A plan was developed that involved doing an abbreviated cross-shelf survey (i.e., inshore to mid-shelf) working our way southwest down to the second transect line from the end of the survey grid. Then, work would proceed along the outer shelf stations back to the northeast. The plan enables a core set of stations to be sampled before the Palmer might have to conclude its sampling program and steam towards the Gould.
The morning steam in bright sunshine, but very cold temperatures, was through solid pack ice and there was some backing and ramming to get through some pressure ridges. About mid-day, whale spouts were seen in open leads and a number of penguins were spotted in small groups along the trackline. About the same time, the clear skies began to cloud over. The afternoon steam between stations #28 and 19 put us in lighter ice pack with more open cracks and leads. The two ships arrived at station #19 about 2100 hrs. The Gould, able to move around the area on its own steam, actively started looking around the area for a suitable location to set up an ice station. Just before the Palmer left the site around 2230 on the 14th and started steaming for station #52, an XBT was dropped at the Gould's request to provide them with a temperature profile.
John Klinck reports that on 13 August, the CTD group did one station early today before we halted operations to meet the Gould.
Station #51 (513 m) near the entrance of Marguerite Bay has a now typical structure with a mixed layer to 70 m with no structure. One strong reversal in O2 and temperature occurs at about 120 m, but otherwise there is only small-scale variability. A weak O2 maximum occurs at 340 m but there is no hint of a temperature maximum. Deep temperature is nearly uniform over 200 m (1.4°C). Bottle sampling at this station was cut short above 100 m as the wind shifted and the ice pushed against the ship. After some effort, the CTD was recovered. Surface water samples were taken.
Jose Torres reports that since his last report on 5 August, his group has completed two MOC-10 tows (at stations #34 and 46), two under-ice dives (at stations #43 and 50), and several live animal collections with the Tucker trawl, in addition to about 100 additional individual measurements of metabolism and excretion.
Results from our most recent sampling efforts have been consistent with previous observations. Adult krill were captured in greatest numbers at station #34 in the vicinity of Adelaide Island and Laubeuf Fjord. Peak concentrations were found at depths of 200-300 m. Adults were virtually absent in our offshore sampling at station #46, but the overall diversity of the catches were higher, with a greater representation by fishes. Crystal krill (Euphausia crystallorophias) and Thysanoessa macrura, the other two dominant euphausiids, were important components of our catches at both locations in the shallower (0-200 m) depth strata.
Under-ice sampling with SCUBA has revealed Euphausia superba larvae at all six sampling locations, with peaks and valleys in abundance. Our two most recent dives have been in areas of low larval concentrations. Five of our six dives have been located approximately mid-shelf .
Ari Friedlaender reports that on 13 August, marine mammal observations began at first light this morning as we steamed towards the L.M. Gould. Skies were partly cloudy with excellent visibility. Ice conditions were 10/10 with vast floes segregated by ridging that covered nearly on half of the surface area in some points. We passed through an alley of icebergs lined up north-south across the Bay and then approached the Gould. No whales or seals were seen by the time we reached our rendezvous point. Surveys ended at 1300 at the meeting point. As we retraced our tracks to the west, one crabeater seal was seen.
On 14 August, the sighting effort by Friedlaender and Prizl began at 1030 as the Palmer ploughed an ally for the L.M. Gould, around the southern tip of Adelaide Island, towards station #19. Sighting conditions were excellent with clear skies and several miles of visibility. The air temperature was less than -20°C, and the ice was 10/10 vast floes with weathered snow and ridging. There were small clusters of thin, narrow, leads that extended for 1-3 kilometers each. Large numbers of Adélie penguins were seen throughout the transit (see Bird report), as was one single crabeater seal. At 1318, blows were seen ahead of the ship in various distances. A single minke whale was seen spy-hopping through a small fissure in the ice approximately 600 meters in front of the ship. Two other minke whales were seen several times in a thin lead 1.5 miles away, and another whale, probably a minke, was seen blowing 3 miles from the ship. All of the sightings occurred within 10 minutes of each other and as the ship approached the area of the whales, there was an apparent network of thin leads that extended somewhat perpendicular to the coast. The first cues seen were blows that sprang up from seemingly complete ice coverage. Due to the low air temperature, the blows were easily visible against the horizon and they hung in the air for 3-5 seconds. The area where the whales, and penguins were sighted, is not far from an area of numerous whale sightings from the first GLOBEC cruise. Effort ended at 1400 when the Gould paused to fix their engines. A minor victory for the whale observers to have fine sighting conditions in an area where whales were present.
Chris Ribic and Erik Chapman report that on 13 August (JD-225), they
surveyed for 4 hours between station #51 and the L.M. Gould, 20
miles NE of station #42. Visibility was excellent and ice conditions were
10/10ths concentration with a few small areas of open water. Adélie
Penguins and Snow Petrels were relatively abundant in the beginning of
the survey. But their numbers dropped off as we approached the area near
the Gould where there were lots of icebergs and pressure ridges.
Snow Petrels were mainly flying high over the ice, and directionally, heading
to our southwest. A group of Southern Giant Petrels were also seen on the
ice, but they were not associated with a carcass. A summary of the observations
is the following:
|Southern Giant Petrel||6|
A night survey was conducted for an hour and a half last night between stations #50 and 52 and 5 Snow Petrels were seen during that time.
On 14 August (JD-226), the marine bird survey took place for 4 hours
and 15 minutes as the Palmer cleared the way for the L.M. Gould
to station #19. Visibility was excellent once again and ice concentration
was between 9 and 10/10ths coverage. Snow Petrels were not abundant and
Adélie Penguins were relatively abundant. Groups of up to 12 birds
were seen in an area where whale observers saw minke whales. A summary
of the observations is the following:
|Southern Giant Petrel||1|
BIOMAPER-II/MOCNESS report (P. Wiebe, C. Ashjian, and S. Gallager):
No BIOMAPER-II towyoing or MOCNESS tows were taken on either the 13th or 14th of August.