10-12
December 2001
Monday
Minutes
The
Third U.S. Southern Ocean GLOBEC (SO GLOBEC) Science Investigator Meeting
started with a welcome from Eileen Hofmann, which was followed by introductions
of the meeting attendees and a welcome from Polly
Penhale and Bernie Lettau from the NSF Office of Polar Programs.
Hofmann
went over the agenda for the meeting and asked
for corrections or additions (none were provided). Next Hofmann went over a
timeline of program activities and showed a table of the SO cruises that
have been completed and remain to be done. She noted that the cruise track
from the German SO GLOBEC cruise overlaps parts of the cruise track and that
a report from the German cruise is posted on the Alfred Wegener web
site .
Program
activities since the 2001 Science Investigator meeting were next reviewed.
The British Antarctic vessel, the R/V James Clark Ross did an extensive
multibeam bathymetric survey in the Marguerite Bay region in February
2001. The bathymetric data from this cruise have been made available to SO
GLOBEC and the SeaBeam data collected during the British cruise have been
provided to SO GLOBEC. Bob Beardsley from Woods Hole Oceanographic
Institution (WHOI) is leading the effort to merge these data sets to obtain
an updated bathymetric map of the SO GLOBEC study region. The British
Antarctic Survey will have another cruise in the Marguerite Bay region
in early 2002 and it is anticipated that these data will also be part of the
larger data base. Bob Beardsley is checking into the availability of the
German bathymetry data as well as bathymetry data from previous cruises to
the region.
The
SO GLOBEC Planning Office has received and published cruise reports from
the five cruises in 2001. The reports are available in paper and in
electronic form on the SO GLOBEC web site.
The
SO GLOBEC session at the 2002 Ocean Sciences Meeting received 50 abstracts
and had a good international response. The abstracts were organized into
two oral sessions and one poster session. Everyone
was encouraged to check the AGU web site for
additional information about the sessions and the meeting.
A
SO GLOBEC poster has been prepared and is available to anyone who wants
one. The poster has been presented at the Ocean Odyssey Meeting in
Argentina in October 2001 by Dan Costa and at the iAnZone and Ross Sea
Conference in Italy in October 2001 by John Klinck. The poster will also be
presented at the Ocean Sciences Meeting and possibly at the European
Geophysical Society Meeting scheduled for April 2002 in France. A similar
poster will be made for the second field season.
Dates
for the 2002 SO GLOBEC process and survey cruises are 9 April to 21 May
2002 (Gould leaves Punta Arenas, Chile on 7 April) and 31 July to
19 September (Gould leaves Punta Arenas, Chile on 29 July). Cruise
schedule information is available on Raytheon
web site. Chief scientists for the 2002 cruises will be the same as for
the 2001 cruises: Wiebe (both survey cruises), Torres (April-May process
cruise), Costa (August-September process cruise). The second survey
cruise is extended because the first survey cruise is shorter and the ship
time is available. Upcoming international SO GLOBEC cruises were next
discussed. These are the United Kingdom austral spring cruise scheduled for
October-November 2002, a German cruise in 2003, an Australian cruise in
January-February 2003, and a Korean cruise to the Bransfield Strait in 2002
and 2003. The United Kingdom cruise may have space available for interested
scientists. Interested persons should contact Eugene Murphy at the British Antarctic Survey.
Upcoming
activities relevant to the U.S. SO GLOBEC program include: 1) preparation
of an article for Oceanography Magazine; 2) the Second International
GLOBEC Open Science Meeting scheduled for 15-18 October 2002 in Qingdao,
China (SO GLOBEC results will be highlighted at this meeting); and 3) a
special issue of Deep-Sea Research on SO GLOBEC results scheduled
for late fall 2002. Papers submitted for the special issue of Deep-Sea
Research can include some work outside of U.S. SO GLOBEC, but the
information must be relevant to the program goals. Information on all
of these will be made available at a later date.
The International
GLOBEC Planning Office is compiling contributions list for a database of
publications related to SO GLOBEC. Those having relevant publications are
encouraged to provide this information to the International Office.
Bob Beardsley next
gave an overview of the 2001 mooring deployment cruise. The objectives of
this cruise were to: deploy the WHOI V/P/T/C moorings, deploy the Scripps
Institute of Oceanography (SIO) acoustic moorings, and to do marine mammal
observations/sampling. The mooring cruise deployed six WHOI moorings, eight
SIO moorings, and six WHOI drifters; and made six bathymetric surveys, six
CTD stations, marine mammal observations, sampled five whales for biopsies,
and collected meteorological data for heat flux estimates. Beardsley showed
a schematic diagram of the C1 mooring to be deployed during the February
2002 mooring cruise. This cruise will recover the six mooring deployed in
2001 and set three moorings. The new moorings will be across the mouth
of Marguerite Bay. Beardsley also said that the 2002 mooring cruise will
recover/redeploy the SIO acoustic moorings (seafloor recorder), undertake
whale observations and collection of whale biopsies, if
feasible.
Beardsley
next discussed the status of the bathymetry data. He noted that there is
little good bathymetry data for the SO GLOBEC study region. The CTD data
and XBT data collected on the survey cruises will be used to correct SeaBeam
data. Also, the data from the James Clark Ross extensive multibeam
survey will be merged with the SeaBeam data. The British Antarctic Survey
wants to collaborate and share data and they are doing bottom coring in
three areas. Also, the SeaBeam data and centerline data from Gould
will be merged into a grid. The next step is to go back and make sure that
the best sound velocity data are used in correcting the SeaBeam data
sets. The gridded bathymetry data could be produced uncorrected now, but
someone will need to go back and check the sound-speed corrections.
Peter Wiebe next
provided an overview of the two U.S. SO GLOBEC survey cruises, NBP01-03 and
NBP01-04. The overall objective of these cruises was to survey the
distribution and abundance of Antarctic krill (Euphausia superba)
over the study area. He noted that on NBP01-03 two automatic weather
stations (AWS) were successfully installed and that the ship's scientific
personnel and some of the crew had an opportunity to visit the Argentine
base, San Martin. The AWS installation was on islands associated with the
Kirkwood and Faure Islands groups, but there are no names listed for the
specific islands on which the weather stations were deployed. Wiebe
suggested that the SO GLOBEC program should provide official names for these
islands. Wiebe noted that there was little luck in finding penguins during
this cruise; however, he said that the "iceberg graveyard" area (near the
northern end of Alexander Island and off Lazarev Bay were hot spots for
krill, seals, and seabirds.
On
NBP01-04 there were two groups doing research directed at the objectives
of the process cruise. The cruise track for this cruise was "simpler" than
that for NBP01-03 because many of the stations could not be reached due to
sea ice. Also, the Palmer worked with the Gould to get it out
of the sea ice and to its stations. He showed images of a rendezvous with
the Gould and of icebergs encountered during the cruise. A major ice
buoy deployed at survey station 74.
The
SeaBeam bathymetry data sets from the survey cruises are very good and
are being combined with those from the James Clark Ross and
Polarstern cruises to the Marguerite Bay region. This should be
beneficial to many.
Wiebe
ended his presentation with a thank you to the scientists and ship's crew
for a great job and an acknowledgment of Mark Christmas and Raytheon's
efforts.
Jose
Torres provided and overview of the first process cruise, LMG01-04. The
objective of this cruise was to give biological detail at predetermined
locations within survey grid. He said that weather dictated many of station
activities and locations. He noted that time on the cruise was devoted to
searching for penguins and seals between Adelaide Island and Pourquoi Pas
Island because these animals were not available at process station 1. The
intent was to provide the needed resources to the predator groups on the
process cruise. Some dive operations took place at end of cruise in Lazarev
Bay. Torres suggested having a drop-off point around Avian Island for
predator groups during the 2002 process cruise so that they will be able to
obtain the data that they need to meet their scientific objectives. He
noted that the only sea ice encountered of the April-May process cruise
was in Lazarev Bay and that this was a good site for transmitter deployment
on seals and penguins.
Dan
Costa gave an overview of the second process cruise, LMG01-06, and reviewed
the cruise objectives and cruise track. He also noted that weather dictated
many of the scientific operations. The original cruise plan called for a
series of ice stations as well as opportunistic ice observations and
sampling with Zodiacs. During the cruise there was an opportunity to visit
the British base, Rothera Station, on Adelaide Island.
Costa noted that the
Gould had significant problems losing water and that the ship cannot
make water while sitting in the ice water. The
plumbing on the Gould froze and burst when conditions got very
cold. Costa said that the Gould is not an effective platform for
working in sea ice. It is also difficult to tow a MOCNESS in heavy sea
ice.
The Gould
visited Dion Island, where an emperor penguin group (nine breeding pairs)
was surveyed on land. There were few Zodiac operations during the cruise,
rather personnel baskets or gangplanks were used to put people on the ice.
CTD measurements were
made in open water and at the ice camps; however, maintaining holes in the
ice was quite a task. Under-ice diving did take place during the cruise, as
well as transmitter deployment on crabeater seals and Adélie penguins.
Costa expressed
concern about the 2002 schedule. The latter departure date put the cruise
during a time of potentially heavier ice. Thus, the Gould will
have to rely more heavily on the Palmerto move it. Costa
expressed the concern that this might hamper the objectives of both
cruises.
Alice Doyle next gave
an update from Raytheon. She first discussed scheduling of the 2002 cruises
and noted the concern about the later time for the second process
cruise. She said that the Gould and Palmer have to go into
dry dock, which takes about 6-8 weeks, between the two SO GLOBEC cruise
periods. The scheduling of the two cruise periods is to allow this
time. She also noted that with ships going in dry dock, everything must come
off ships between the cruises.
Doyle next discussed
the ESP SIP submission and said that it is here to stay, so people need to
get used to it. She said that Brian Stone is the NSF contact for this and
would be available for discussion of the ESP later in the meeting. Raytheon
will work with people to make sure that doing SIPS in this manner goes
well. Doyle said that SIPs for the last SO GLOBEC cruises are due in
mid-January and asked everyone to get them in on time. She said that medical
packets should have been received if a SIP was submitted.
The laboratory
layouts on the Gould and Palmer should be similar to this year
to what was done in the 2001 cruises. She asked if a nutrient technician
was needed on both cruises. The agreement is that this person is needed for
the Gould cruises. She then showed a listing of the Raytheon
staffing of the SO GLOBEC cruises.
Doyle noted that
permission is needed to use real time SeaWiFS data and that the sensor is
turned off in mid-April. She said that procurement of the microstructure
sensors is proceeding and that the sensors should be ready for the April-May
cruise. She also said that new oxygen sensors have been ordered for the
CTD. These sensors are supposed to not require lengthy soaking to
equilibrate.
Jim Dolan, Raytheon
Information Technology, described changes in the ship's electronic mail
policy. The current e-mail policy allows only science-related communications
and no personal attachments. The proposed new policy, which has been sent
to NSF for approval, will allocate a certain daily quota for each user to be
used at his/her discretion. This quota will be about 25k/day and can be
used for scientific correspondence, personal correspondence, and combination
of both. The intent of the new policy is to level the playing field for
everyone using the email system on the ships. However, there will be special
accounts set up for the chief scientists and Raytheon personnel that will
allow a larger quota. Users who go over the daily allocation will have to
pay for the excess. There will be a daily accounting of usage and the quota
allocated for the chief scientist has not yet been determined. Electronic
mail related to public outreach will have to be pre-approved through NSF
(in SIP). Dolan said that this policy needs to be approved by NSF, but
Raytheon is expecting to implement it by the first SO GLOBEC cruise.
Bill Fraser suggested
setting up one science account and one personal account. Dolan responded
saying that email not directly related to cruise, should not be done or
should be paid for by the user. Wiebe suggested setting up an account to
pay for non-cruise-related e-mail. He also asked that as chief scientist
could he have the best picture of the day accompany the daily report. Doyle
said that this is possible within reason?the picture does not have to be
high resolution. Hofmann noted that the picture of the seal with an
attached satellite transmitter sent by Dan Costa with his cruise report has
gotten wide publicity.
Dolan next said that
a new SIMRAD system is being installed on the N.B. Palmer and should
be operational by the final cruise SO GLOBEC survey cruise. So, this will be
the first cruise with the new bottom mapping system. He said that a lot of
personnel allocated to project to make sure this system works.
Doyle next said that
expense reports for the meeting were available and if anyone had questions
to contact her. She said that the expense reports should be submitted to
her along with the yellow travel authorization form. Hotel rooms will be
billed directly to Raytheon. Lunch and dinner reimbursement can be
determined by deducting 25% from $46 because breakfast is provided.
Bernie Lettau next
gave an update from NSF. He said that there is an issue with the
microstructure measurements and that he is looking to the SO GLOBEC SSC to
provide input on how to solve the issue. Hofmann said that the issue
is that Tom Powell who was funded to make microstructure measurements (a
key measurement in this program) has withdrawn from program and plans to
return his funding to the NSF. As a result, one field season has already
happened with no microstructure measurements. She said that Alice Doyle has
funds that have been allocated for microstructure sensors and that these
have been ordered. Laurie Padman's group is now taking over the
responsibility to make the needed measurements. Lettau said that NSF
would like a formal proposal from Padman to do this work so that there
can be a contractual relationship. Hofmann asked if a standard peer review
of the proposal would be needed since the need for the measurements was
covered in the initial proposal that was funded. Lettau said that no external
review would be needed. Padman asked if this can be done before NSF
received notification from Powell. Lettau said that the two activities can
go forward simultaneously. He also said that he has not received
notification of Powell's withdrawal from the SO GLOBEC program. Hofmann
said that she will remind Powell to notify NSF.
Polly Penhale said
that she had received a letter from the U.S. GLOBEC SSC (via Hofmann
discussions) about funding to support synthesis and modeling activities
following the SO GLOBEC field work. Penhale said that she is anticipating a
June 2003 deadline for proposals in this area which will mean issuing an
announcement of opportunity (AO) in early 2003. She requested guidance from
the SO GLOBEC SSC for the AO. She also noted that Phil Taylor in Ocean
Sciences will be a good resource for her in structuring a synthesis and
modeling program because of his experience with the JGOFS program. Penhale
said that in order to apply for these funds, data from the individual
components and investigators needs to be publicly available, which is
consistent with the GLOBEC data policy. Individuals or groups that do not
meet the data policy requirements should not apply for additional synthesis
and modeling funds.
Wiebe said to contact
him if there are questions about posting data to the GLOBEC data management
system. Hofmann said that much of the preliminary data are on the data
system; this is the information that is in the individual cruise reports.
Daly asked if there are data requirements for Office of Polar
Programs. Penhale said that this is in the award letter sent to individual
investigators.
Bob Beardsley brought
up the issue of air flow distortion around the Palmer and
Gould and the potential effect of this on meteorological
measurements. He mentioned that there are computer programs that can be
used to determine air flow around ships that take into account the ship
structure. The intent is to use these programs to analyze the air flow
around the Palmer and Gould. The results of the analysis
would then be used to modify the locations of meteorological sensors, such
as wind speed and direction. Beardsley said that he brought this up at the
ARVOC (Antarctic Research Vessels Oversight Committee) meeting in October at
Woods Hole. He indicated that he would continue to pursue this.
The issue of needing
a nutrient technician on the Gould cruises was raised again. Dan
Costa said that this person could do nutrients and salinometer measurements
on the cruise. He said that the person on LMG01-06 was not aware that
measurements other than nutrients were needed and that this caused some
confusion and misunderstanding on the cruise. Chris Fritsen said that the
nutrient technician did samples to support his water column and sea ice
work. Doyle asked if this person was really needed for the first cruise
when sea ice is not extensive. Torres said that there are still background
measurements that are needed and Daly said that it is important to have
calibration information for the CTD, as well as water column measurements.
Torres said that the nutrient technician on LMG01-04 seemed to not be
occupied full-time. Doyle said that this person could then do the needed
oxygen and salinity calibration samples. Torres said that he would like the
person to run ammonia determinations to help with some of his one-board
experiments. Wiebe said that it is important to get as much coverage as
possible during the first cruise. Bob Kluckhohn (Raytheon) said that part
of the problem with the Gould nutrient technician was a breakdown in
communication in that the needs were not listed clearly on the SIPs. Costa
was because the need for this person was decided after the SIPs were
submitted. Hofmann said that the discussion indicated the need for a
nutrient technician on both Gould cruises.
Beardsley said that
it would be helpful if people indicated specific areas for which they wanted
good bathymetry. If there are special mapping requirements this can be
worked into the cruise plan for the first cruise.
Laurie Padman asked
about satellite data and said that there is not much of this on the GLOBEC
web site and that it would be helpful to have more. Joey Comiso (NASA) said
that the complete sea ice data set is available and he will provide a link
to it. Wiebe said that this can be linked to the GLOBEC data management
site.
Following the lunch
break, Debbie Thiele, who represents the International Whaling Commission
(IWC), made a presentation. She said that the IWC Scientific Committee is
very excited about the preliminary data from the first SO GLOBEC field
season. She extended a thank you to SO GLOBEC from the IWC for the
opportunity to participate in the program. She said that on the
first season cruises the IWC had been able to obtain visual surveys, whale
biopsies, and photographic identification of several animals. She
said that IWC observers will be going on the U.S. SO GLOBEC cruises in
2002 and the British Antarctic Survey Frontal cruise, scheduled for
October-November 2002. She said that she is now working on a review paper
on cetaceans in the Southern Ocean which should be available in 2002. Thiele
also said that there will be a special session on SO GLOBEC results at the
IWC Scientific Committee Meeting in 2003.
Thiele next presented
of framed photos of whales from the Southern Ocean to Alice Doyle from the
IWC for the Gould, the Palmer, and Raytheon. Thiele said
these were in thanks for the assistance received from the ship's crews and
Raytheon personnel. She said that the fine-scale data obtained on the SO
GLOBEC cruises will be considerable help to the IWC, especially in regard to
environmental issues.
Bob Beardsley next
reported on the status of the AWS that were deployed during NBP01-03 on
Kirkwood Island (#8930) and Dismal Island (#8932) in May 2001. (This report
is available as a PowerPoint presentation.) He
said that the AWS use a R.M. Young wind monitor and measure temperature,
relative humidity, barometric pressure. Data are then transmitted via an
ARGOS link to the Antarctic Weather Research Center at the University of
Wisconsin (AWRC). The data on the AWRC site are of excellent quality and the
measurements from the two stations agree well. This is expected since the
stations are separated by about 30 miles. This suggests that the
orientation of units was done correctly. Beardsley thanked the Raytheon
staff for their efforts in successfully deploying the AWS. He mentioned
that it might be worth checking the AWS on the 2002 cruises. Doyle
said that this is a good idea. Wiebe said that this would have to be done
on the first cruise and could be added to the cruise plan.
Beardsley said that
the winds measured at Rothera lower and much more polarized than those
measured at the AWS locations because of mountains surrounding Rothera.
Thus, it is not a good idea to use the winds measured at Rothera for winds
in Marguerite Bay. A comparison between winds measured at the two AWS and
those measured at Palmer Station have better agreement. Comparison
with the winds measured on the Palmer was good when the Palmer
was near the AWS. Beardsley said that the flow distortion around the ship
has about a 10% effect on wind speed. The comparison of winds at two
stations is good when done with wind stress. The two AWS do not provide
redundant information and can help with approximate timing of storms.
Beardsley noted that the stronger winds tend to be southward. He
said that the meteorological data use the convention of day 1.5
being noon on 1 January. Wiebe noted that the ship data use the other
convention, with year day 1 being 1 January. Padman asked if there should
be a standard convention. Wiebe said that JGOFS uses both and that Bob
Groman (GLOBEC data base manager) maintains the data with both
conventions. Wiebe said that the U.S. Naval Observatory uses 31 December
at noon to 1 January at noon as day 1. The issue is to get the convention
straight in the database.
Wiebe next lead a
discussion on the 2002 fieldwork plans. He began by reviewing the 2001
field season. He said that the 84 stations in survey grid and the 5 process
sites proposed for the 2001 field season did not take place as planned.
He said that there is a need to develop a conceptual framework on how second
cruise will be done. He suggested starting by constructing a timeline for
the cruise. He also said that he did not anticipate having to spend much
time on space allocation on the ships because there should not be much
change from what was done on the 2001 cruises.
The 2002 field season
discussion was tabled for later when Brian Stone (NSF) arrived to discuss
the ESP system and long-range planning with Raytheon. He said that efforts
are ongoing to redo the current system and that the new system is following
the FastLane model for submission of information. The intent is to move
toward a web-enabled program and the goal is to have a purely web-based
system by FY2004. He said that parts of ESP are working and the intent is
to continue to maintain this system. The new system will be called Polar
Ice.
Wiebe next continued
the discussion of the 2002 cruises. Alterations to personnel will be two
IWC people in April 2002. Ashjian asked about science writers on the
cruise. Hofmann said that National Geographic is trying to find a corporation
to underwrite expenses, but that this is not likely to happen. Penhale said
that science writers should be coordinated with Peter West at NSF.
Roger Harvey said
that he would prefer to have two people on the April 2002 cruise instead of
on winter cruise. Chris Fritsen said that his group will not go on the
April cruise so Harvey could have these bunks. Thiele requested one bunk on
the April Gould cruise for an IWC observer. Wiebe noted
that Harvey's bunks on the Gould July 2002 will go to zero. On
the Palmer April 2002 cruise, the ODU group needs one more person
for CTDs. There are two berths for science writers and two additional
berths available. On the Palmer July 2002 cruise the berthing is
already at a maximum. Hofmann said that she will contact Chilean colleagues
and see if they have an interest in the April survey cruise. Beardsley
asked if the Raytheon ETs would be responsible for checking the ASW during
the April Palmer cruise. Doyle said that Raytheon can take care
of this. Wiebe summarized the April survey cruise as consisting of AWS
service, mooring bathymetric survey (sites not done in 2001), diet sampling
of birds/penguins, survey predator hot spots, and krill migration
study.
Bill Fraser next
discussed setting up a field camp at the south end of Adelaide Island
on Avian Island during the April 2002 Gould cruise. The
field camp would be used for predator studies. The field camp would be
occupied for 7-10 days and then the predator work would move south to
Marguerite Bay. Fraser said that, in April, Adélie penguins are at
the breeding colonies and a field camp would allow obtaining time series of
diet samples. He noted that data from 2001 indicated that male and female
penguins are taking different prey at different depths. He said that it
would be good to have a Mark III Zodiac at the field camp for safety, so
that people could head to the nearby Chilean base if needed.
Costa noted that a
field camp will allow the predator groups to get work done while the open
water work is taking place. Jennifer Burns said that she is talking with
scientists at the British Antarctic Survey about getting into Rothera to do
some work with seals. Torres asked if there is any interest in working with
elephant or fur seals. Burns said that there are any plans to tag
these. She is working on getting permission from Rothera. Wiebe noted that
the 2002 April planning would need to include time to stop at Rothera to
drop the Burns group, stop at Avian to drop Fraser's group, and then go to
process station 1. Torres noted that unless there is a protected area, he
cannot deploy gear in winds greater than 30 knots. Fraser noted that the
Chileans have a hut on Avian Island that is in a sheltered and protected
site that can be used by the field team if needed. Torres noted that if the
if predator groups still have work to do, the Gould can move to
process station 2 and then pick them up. Burns said that her group
is allowed to go into Rothera, they will be limited to working close to
shore. Torres said that the plan for the April 2002 cruise will probably be
to go to process sites 1, 2, 5, 4, George VI Sound, and then to Lazarev
Bay. Burns noted that north of Adelaide Island in Matha Strait is a hot
spot for crabeater seals. Thiele noted that this is also a hot spot for
whales and krill. Wiebe asked if there was interest in putting a process
station at this site. Torres suggested also sampling in Hanusse Bay or
Crystal Sound. The agreement was to think about the Gould process
cruises and return to the topic later.
Joey Comiso (NASA)
next made a presentation on satellite-derived
distributions of sea ice cover in the Antarctic and specifically in the
SO GLOBEC area. The data from 2001 show the changes in the sea ice cover in
the Antarctic Peninsula region. He noted that there was no sea ice in April
and May in the SO GLOBEC study region. Comiso said that he can provide sea
ice data upon request.
Comiso
noted that the sea ice area has not changed for the Southern Hemisphere,
except for the region of the Ross Sea, where it is increasing, and
the Bellingshausen Sea, where it is decreasing. The question is then is the
sea ice being advected from the Bellingshausen Sea to the Ross Sea OR is
something going on in the Ross Sea? The largest change in sea ice extent
and area occurs in the austral autumn. Comiso showed that temperature and
sea ice extent can be correlated. Thus, temperature time series can be used
as a proxy for what has happened to sea ice extent in the last twenty
years. This correlation shows a warming trend around the Antarctic Peninsula
(Bellingshausen Sea) during 1982-1999. Comiso said that sea ice extent data
depend on how well ice margin is defined. The next sea ice satellite launch
is scheduled for August 2003 and there will be aircraft overflights for
validation. The disadvantage is that SO GLOBEC will be over by then.
Don Perovich made a
presentation on results from the sea ice studies
undertaken during the July-August 2001 Gould cruise. This
presentation is available as a PowerPoint
presentation. Perovich said that the data from this study will soon be
available via the GLOBEC data management web site and on CD-ROM.
Following the
presentations, discussion returned to cruise planning for the
August-September 2002 Gould cruise. Wiebe noted
that the original plan in 2001 was to start at the southern end of the
study region and move northward. However, changes will have to occur in
2002 since the cruise is two weeks later than in 2001 and the desire is to
avoid having the Palmer move the Gould everywhere. Ice camps
should not be a problem on the 2002 cruise. It is not clear if the
Gould can get to process station 3. Wiebe asked if this station is a
priority. Costa said that some felt that not visiting process station 3 was
significant scientific loss. Fritsen said that the observed sea ice
processes in 2001 did not cover very large range. The objective is to try
to get ice camps in areas where sea ice has been in place as long as
possible in order to get a gradient in sea ice history. Process station 3
is at a location where the change in sea ice is greater. He suggested
staying away from coastal current because of shear stress effects on sea
ice. Hofmann mentioned that the coastal current may be a seasonal feature.
Wiebe asked about
starting with a basic scenario for the cruise. Costa said that because of
the later time of the cruise, it is possible that many predators will be
missed as they may have already moved north. There was concern expressed
about moving into heavier pack ice and no open water. Thus, another option
is to get into Crystal Sound/Marguerite Bay early in the cruise to catch the
predators. Torres asked if there is a coastal polynya there? Costa
said that the Gould could not get in there at the end of the August
2001 cruise although they had planned to go in to find polynya. Wiebe
said that the Palmer observed lots of open leads, but not a polynya.
Fraser said a consideration should be if hot spots are available. If
so, the complete system should receive priority as sampling site for both
ships. He said that the polynya off Rothera, near Avian Island, is an area
where predators are focused all winter long. Wiebe said the station grid
should be extended to include this and to target it at the end of the cruise
for special studies.
Beardsley
said that this is an area where the coastal current is coming down off
Adelaide Island. He suggested extending the first transect inshore to get a
sense of where that flow is coming from. Wiebe said that fifty days gives
more opportunity to do 90 stations and still help the Gould. Fraser
suggested doing a rapid survey to see what it is about the region that
attracts the predators. Wiebe suggested working out a sampling strategy for
a hot spot. Ashjian noted that in 2001 an opportunity was missed when
hundreds of seals were observed around ship and this spot was never found it
again after the survey. Thus, we should not do entire grid and then come
back to hot spot because it might not be there. Harvey suggested having a
plan for expected hot spots that allows the two ships to rendezvous. Costa
said a hot spot process station could be the last site. Process site 2
worked reasonably well for everyone. He suggested deleting process site 4
entirely. Fritsen said this is a reasonable target since the cruise has ten
extra days to allocate to studies. Wiebe said that cruise planning has to
be done with a scenario that makes sense from both perspectives
(Palmer helping Gould).
Costa
asked about the Palmer getting stuck on the cruise that followed
the August 2001 SO GLOBEC cruise. The response was that the Palmer
got stuck in mouth of Marguerite Bay at end of September/first of October
and that there was 15-20 m of overrafted ice. The comment was made that the
Gould should not go into Crystal Sound without the Palmer
nearby. Wiebe said that on the August 2001 cruise, the Palmer did
not have any problem working along the mid and outer shelf. Getting
to stations inshore required lots of backing and ramming. Wiebe
said that he would prefer to work the survey grid in one direction and
requested people to think of options of how to meet needs of both cruises
and bring this to the discussion on Wednesday.
The meeting was
adjourned.
Tuesday
Minutes Hofmann began the meeting by letting everyone
know that the SO GLOBEC SSC met the previous night at dinner. One result
of this meeting is Dan Costa agreed to host a krill hot spot meeting in
late June 2002 in Santa Cruz, CA. More information on this will be
forthcoming from Dan Costa.
Note: Tuesday was devoted to presentations
of results from the 2001 field season. The list of presentations is given
in the meeting agenda and abstracts for individual presentations are available.
The following is a brief listing of the presentations and some results.
Presentation
by Limeburner (available as PowerPoint)
on surface drifters
-deep floats were not deployed in 2001 (float
at 200-300 m)
-deployed fourteen drifters in 2001
-had poor data return (average of 50 days)
-inflow occurs in top ¾ of mouth of
Marguerite Bay; outflow occurs in bottom ¼ of mouth of Bay
-cruise in February 2002 to recover moorings
and deploy moorings, drifters, and floats
-new moorings will be placed across mouth of
Marguerite Bay
Presentation by Hofmann
on hydrography and circulation -described distribution of Circumpolar Deep
Water
-much greater variability in NBP01-03 than
NBP01-04
-seasonal variability in the above pycnocline
waters
-no Antarctic Surface Water present in winter
-presence of UCDW is not seasonally dependent
-modified UCDW dominates thermohaline
properties of this region
-what is going on above 150 m is seasonally
variable
-gyre sets off Adelaide Island shelf
-changes in the strength and location of the
ACC may have pronounced effects on the residence time and flushing of the
subpycnocline waters on the WAP continental shelf
Presentation
by Fanning (available as PowerPoint) on nutrient
distributions
-upper ocean nutrient values increase between
cruises, suggesting remineralization
-ammonia: very high concentrations (> 4
µM) on NBP01-03
-ammonia concentration declines in upper
water column
-deep ammonia concentrations remain at
zero
-standing stock of ammonia decreased in
NBP01-04
-nitrate:ammonia change ratio suggests that
all of nitrate did not come from nitrification in the same
waters
-very high standing stock of ammonia in
Marguerite Bay
Presentation
by Howard (available as PowerPoint) on ADCP
measurements
-good regional coverage and process data from
Gould process sites
-ice really interfered with data collection
in winter
-currents at shelf break - eddy is
present
-high frequency variability in
data
-evidence of strong vertical
shear
Presentation
by Fritsen on sea ice
-region has early and long-lasting ice
cover
-program consists of remote sensing, ice
observations, ice sampling, ice instrumentation, ice/water/krill interface
dynamics, and modeling
-strong latitudinal gradient from southern
end to northern end of grid (thickness - change of ~20 cm)
-no clear cut vertical trend of algal
biomass
-a lot more biomass in the ice than in the
water column
-not a lot of nutrient depletion
indicated
-two weeks can lead to significantly
different ice growth trajectories
-two weeks can account for substantial
difference in primary production and algal growth
-flooding-freezing prevalent; mesoscale
gradients exist in region
-late-forming ice cover; cycling/degradation
dominated system (physically and biologically
mediated)
Presentation
by Ashjian on Antarctic krill distribution
-larval krill distribution
-big difference between amount of data
between two Palmer cruises (ice cover and technical
difficulties)
-survey between 25-250 m
-greatest abundances of larval krill along
pycnocline (AASW, Winter Water, and upper portion of modified
UCDW)
-for NBP01-03: high abundances above
thermocline and associated with Winter Water; maximum abundances found at
50-100 m depth range; and higher abundances at offshore portions of the
shelf, shelf break, and in the southern portion of the grid
-abundances of plankton in the water column
were much reduced during winter cruise
Presentation
by Torres on Antarctic krill metabolism
-describe abundance and distribution of
larger size classes of krill
-focus on metabolism, excretion, and
physiological condition
-distribution of adults tended to be towards
the coast
-adults completely absent around process
station 1
-metabolism measurements: requires about 50%
less energy to get through day in winter
Presentation
by Wiebe on BIOMAPER II acoustic mapping
-some vertical migration did occur in
northern end of grid
-hot spots for krill off Alexander Island,
Laubeuf Fjord, and northwest corner of Alexander Island down to Lazarev
Bay
-major concentrations were mostly in upper
120 m of water column
-acoustic backscattering was substantially
lower during NBP01-04 compared to NBP01-03
Adjourn
for lunch
Following
lunch, the winter cruise plans for the Gould were again briefly
discussed. Costa discussed extending the study region to include a transect
along the northern end of Adelaide Island (Crystal Sound), working down the
coast of Adelaide Island, going down towards process station 3, moving
inshore near process station 2, and then out to process station 1, with ice
camps at each station. Time during this will be spent looking for predators
because most predators will move out of southern region at this time. The
plan is to occupy the hot spot areas early in the cruise on when conditions
are more favorable, to do ice camps, and to make a commitment to predator
work as available. The amount of time spent at each site is difficult to
determine in advance. Three to four days at Crystal Sound would be ideal
for the predator work.
Ashjian asked if this
plan will mean that the Palmer will lose transect time. Hofmann said
that the intent is to do joint-ship operations early on in cruise. Ashjian
said that the Palmer could do the first three survey lines while
the Gould is working in Crystal Sound. Wiebe said that the intent is
to keep the two ships within a region, not next to each other. There is
also a need to cut down number of stations in grid (70-80) based on the
experience from the July-August 2001 survey. Fritsen said that this plan
gives 42-44 days with 8 days at each station for Gould. Wiebe
said that Costa and Fraser need more time throughout cruise to look for
animals. Doyle asked if Fraser's needs would be better served on
Palmer. Wiebe said that the Palmer bunks for the winter
cruise are already filled. Costa said that there needs to be more effort at
time scheduling for both ships. Wiebe said that the predator people need
access to animals and Ashjian asked if working in Crystal Sound could mean
losing process site 1 (trade-off). Fritsen said that it is important to get
a site to the south. Costa said that process site 1 probably would not be
lost, but time at the site could be significantly shortened. Costa said
that the Gould might not be able to do Crystal Sound on its own
(joint ship operations). The intent is to tag birds and seals and do
stomach contents on ice floes in this area. Burns said that the seal
group had worked on remnant ice during the previous cruises and so this
is possible. Costa said that at the beginning of cruise is the greatest
opportunity for Gould to operate on its own; however, the decision to
do this is up to the captain. The discussion was ended at this point and
will be returned to on Wednesday.
Presentation
by Daly on Antarctic krill distribution and metabolism
-evaluate behavioral and overwintering
strategies using acoustic data, net samples, and dive collections
-estimate a carbon and nitrogen
budget
-both larval and adult krill found in large
numbers in back bays of Marguerite Bay
-during fall: abundant larvae; larvae under
sea ice; no juveniles; immature adults in fjords
-during winter: larvae in water column and
under sea ice; no juveniles; aggregated adults; little to no
growth
Presentation
by Wiebe on ROV and microzooplankton studies (for Scott Gallager)
-ROV work under sea ice for larval krill
distribution
-presented video of larval krill under ice in
large numbers
-largest concentrations associated with rough
ice and deep protrusions