We are homeward bound!

Complete cruise track through location 21 April 2011.

At 05:25 local time on Tuesday, 19 April 2011, the rosette from station 140, the easternmost station we planned, and the last one on CLIVAR S04P, was brought into the Baltic Room. This completed the over-the-side work for our cruise, though it took a day to analyze the samples that we backlogged as we crossed the eastern boundary of our study area. We arrived at the eastern end a little earlier than expected due to an unprecedented (for this cruise) eight day string of days with light winds, plus our equipment worked nearly flawlessly.

Recovered big float (sea pig) shows some of the unusual-looking sea life.

So what did we do next? We went on an oceanographic treasure hunt! Believe it or not, five days earlier a satellite had reported to its base station that a 400 meter long biophysical mooring for Dr. Richard Limeburner (Woods Hole), deployed in 450 meters of water more than ten years ago by Jim Ryder (the mooring tech on our cruise), but lost in 2001 when it failed to rise to the surface when triggered to do so, had all of a sudden come to the surface and contacted the satellite. (Good batteries!) The location was only about 8 hours away. So after our final station we motored over to its last reported location and – voila! – there it was! Jim, the RPSC marine techs, and our students and other helpers then set to work, recovering the entire string of instruments, covered with ten years of marine growth. Everything was cleaned and will be returned to Dr. Limeburner. What a wild coincidence!

We are now on our way to Punta Arenas, Chile, which is our end port for this long cruise. We’re getting a bit of a weather blast today – after all, this is Drake Passage, infamous for its heavy weather – yet we are actually ahead of schedule and are arriving a little early. We still will not be able to begin our unloading until Monday, due to Easter.

An Acoustic Doppler Current Profiler recovered with 10 years of marine growth.

Tonight we will hold a little variety show on the ship, featuring skits and music from our “polliwogs” (those for whom this was their first Antarctic crossing) plus some of the “red noses”. There will be a traditional induction for the polliwogs tomorrow morning.

And that’s just about that for this cruise. It’s been a long haul – 64 days at sea without a port stop is a new record for most if not all of us. But we achieved our scientific objectives (except for the iced-up southern end of P18 and mooring recoveries there), and enjoyed a safe and productive time at sea. We are very grateful to our shipmates from Edison Chouest Offshore, who operate the Nathaniel B. Palmer and support us and our science so well, thankful for our support from our seven colleagues from Raytheon Polar Services Corporation, and deeply appreciative of our support for this venture from the National Science Foundation, the National Oceanic and Atmospheric Administration, and the National Aeronautics and Space Administration.

We did it!

All is well on the Nathaniel B. Palmer.

Jim and Alex

Not everything on a research cruise goes as planned or hoped. We headed south last Saturday on a dual-purpose mission. The NOAA research ship Ronald Brown had stopped southward progress at an iceberg corridor near 69°S in 2008 when doing the north-to-south “P18″ cruise for our long-term program. We hoped to extend their work south to the Antarctic continental shelf break somewhere near 100°W. There was also the issue of mooring recoveries in that same general area for LDEO investigator Stan Jacobs. We knew from satellite images sent to the ship that sea ice covered nearly 100% of the surface in the area, but the Palmer can handle sea ice if not too thick. Still, we decided to first see how long it took us to get to our desired end point near the shelf break, allotting a certain maximum amount of time to icebreaking (in accord with our master plan for the remainder of the cruise), at which point we would know how much time we had for our work plus the icebreaking and steaming as we headed back north. Admittedly success with the mooring recoveries seemed remote because those could not be done in full ice cover, but one never knows until trying.

Ice party alongside the Nathaniel B. Palmer.

We reached the ice edge at the expected point along the track and progressed well at first. Then the going got tough, not so much because of ice thickness as because of the large amount of snow on the ice. Snow rubs against the ship’s hull much like sand would, sapping power and momentum as the ship presses forward. Only about 20 miles into the ice (20 miles straight line, but many more miles as we worked around large snow-covered floes) the Captain and Ice Pilot decided enough was enough. In the morning conditions looked no better, so we took advantage of being in a large floe to have a brief ice party for those on board, i.e. a chance to be on the ice a bit. We had a good time – playing soccer, walking around, playing in the snow. After everybody was back aboard we pulled into a nearby opening in the ice and did a CTD cast. That cast showed nothing remarkable compared to nearby data from 2008. There we were, nearly 50 miles from our targets – either the shelf break or Jacobs’ moorings – but we could not go further south. There being no point to lingering, we headed back north to the main 67°S line.

Playing soccer on ice.

Thus we were not able to extend the P18 line south through the ice to the continental shelf break, and we were not able to recover any of Stan Jacobs’ ice-covered moorings. The only benefit of the way this worked out was that we spent one day’s time and fuel less on the excursion than planned so now have some weather time in the schedule before the end of science activities in five and a half days. This should enable us to not only reach the eastern end of the S04P section, but also to sample its eastern boundary region appropriately.

We always enjoy our trips through the ice. We did not see many penguins this time (though there were a few, including Emperor penguins) but there were many seals hauled out onto the thicker floes. The leads (openings in the ice) are freezing over and there are many 4 to 10-foot holes punched up through the thin ice. The culprits? Orcas (Killer Whales) on the lookout for seals on the thicker ice nearby. Jim saw a pair of them stick their heads out of one of the holes to take a look-see.

The weather has been unusually good. That may well change, but we are back on “the line” and for now we are mowing down the final stations one by one, making very good progress. Everyone has their sights set on keeping steady and focused: Get the job done. Then go to port!

All is well on the Nathaniel B. Palmer.

Jim and Alex

The planned P18S track to (and slightly beyond) the shelf break along with the 06April2011 ice conditions. If conditions stay much the same, our "P18S" track would run slightly east of that shown, in more favorable ice conditions. Ice coverage is currently ca. 100% in the area of Stan Jacobs' moorings. We are not equipped to recover moorings in ice-covered waters.

RVIB Nathaniel B. Palmer NBP-1102/S04P Weekly Scientific Report 07, 07 April 2011 from Jim Swift, SIO, Chief Scientist, and Alex Orsi, TAMU, Co-Chief Scientist

ca. 67°S, 114°W 2130 Z 07 April (1330 local) -0.4 degC (31 degF)
winds 26 knots from NE en route to station 114

We have increased our basic CTD station spacing to 60 nautical miles, from the original 30 nautical miles. We kept to 30 over the core (and highest priority) part of the  cruise plan. We knew, however, that when we crossed into the Antarctic Circumpolar Current, which we are now sailing in and along, there was little oceanographic damage switching to 60-mile spacing, which helps save time. The station plan includes runs to the continental slope with more closely spaced stations at the ends of the P18 and S4P lines. Ice conditions at the end of the P18 line (see attached file for today’s ice map) may allow us to make it to the shelf break, perhaps a little east of the intended line, within the time we will allot to that portion of the cruise plan.

The pace in the labs is now a little more relaxed.  With a plan in place regarding how we intend to complete the measurement program (within the next two weeks), everyone is focused on simply getting the job done.

Mooring specialist, Jim Ryder, in his element, deploying the Yuan/Sprintall mooring.

Temperature and salinity differences with the 1992 Ioffe occupation of S04P continue in a similar vein to those reported earlier: away from the western boundary, the bulk of the water column is a little warmer and possibly slightly saltier now than measured in 1992.

A major activity this week was the deployment of a 4 km string of moored instruments at a specified spot in the ocean for Xiaojun Yuan (Columbia/LDEO) and Janet Sprintall (SIO). Neither PI was on board, but because WHOI mooring expert Jim Ryder was along, they knew – quite correctly – that their project was in great hands. The specifications called for the top float of the mooring to be 100 meters below the sea surface – in ca. 4500 meters of water – plus the mooring needed to be in an area where the bottom was flat, and had to be deployed in reasonably good weather. We used the Palmer’s multi-beam bathymetric mapping system (managed by Chris Linden, RPSC) to map the ocean floor, then we did a CTD cast at the most likely looking mooring deployment spot to measure the water characteristics and verify the bottom depth. There were also a host of XBT casts and one more CTD cast associated with the mooring science program, not to mention the long deployment itself. Add a day of time lost to bad weather before mooring deployment, and you can see why this was quite an operation, and one we are glad to have completed successfully and now have behind us.

A highlight for the science team was tours of the Palmer’s engine spaces this week by Chief Engineer Johnny Pierce (“JP”) and his expert team of engineers. With two of the four large marine diesel engines powered up plus some of the electrical generator diesels, of course hearing protection was needed, and there are hot/dangerous spots to avoid. But ordinary clothes are fine – nothing will get dirty during a tour to the engineers’ nearly spotless work place, as clean and as orderly as can be. Wow!

Shows two of the four 3180 HP marine diesel engines that, in pairs, direct-drive the Palmer's two propellers.

Holidays can be fun on board, so April 1st got some special attention. Even better, some of us who were “fooled” forgot that it was April 1st, adding to the joy of the conspirators and the fun had by all. Check out Juan’s blog for the fun.

We’re a relaxed bunch, well-fed, tired of stormy weather, happy for the present good weather, and working together to get the job done.

All is well on the Nathaniel B. Palmer.

Jim and Alex

ca. 67°S, 139.7°W 0100 Z 01 April (1500 31 March local) -0.4 degC (31 degF) winds 30 knots from NW en route to station 101

Our decision to do a somewhat-shortened version of the 170°W section worked out fine.  (We’ll attach a map to show you where we have sampled to date.)  The weather was great, we completed the 8th (final) station 6 hours before deadline, and the data showed the features we hoped to measure. We then began a planned 50-hour steam to our next station. Half-way through we had to slow down due to the rough ride in moderately heavy weather. The slow-down used all the hours we had gained and then some, but we finally
got back to work.

Map of sampling.

At our last station on the 170°W line a group of humpback whales swam around us – close by – for a couple of hours. Although we have no way to know, they seemed to be enjoying themselves, swimming by in different positions, flapping fins on the water, making grunting sounds, etc. Just listening to their deep breathing was a treat.

As discussed in past reports, east of 150°W we widened our station spacing from the originally planned 30 nautical miles to 45. We plan to keep to this spacing until approximately 130°W.

If weather were ideal, we would deploy the Yuan/Sprintall mooring at 66.6°S, 136°W tomorrow afternoon, but that seems unlikely. There is list of planned events – bathymetric survey, on-site and regional CTD casts, the mooring deployment itself, XBT deployments along the path we steam – some of which can be in any order and some of which must occur in sequence. The team is very well prepared; all we need is good enough weather, which at present is in short supply. Watch for next week’s report to see how it all came out.

Surrounded by whales.

Well-presented general information about our cruise is updated frequently on Juan Botella’s blog. Juan is a high school science teacher from Wisconsin who is participating on our cruise as part of the NSF-sponsored PolarTREC program. You will see that Juan is gifted at describing what we do and he is also an excellent photographer. Please see: www.polartrec.com/expeditions/seawater-property-changes-in-the-southern-ocean.

Life on board has been fine. We eat well (or a little too well in some cases). There are a few group activities such as a themed movie time. We were recently “killed” one by one in the stealthy tag game “murder” which is popular on research ships. (Juan was the winner, meaning the final “murderer” and last “alive”.) The cribbage tournament is into round two. And there are plans afoot for a couple of other group events or activities. Little things, but it keeps life moving along.

All is well on the Nathaniel B. Palmer.

Jim and Alex

ca. 71.8°S, 170°W 2225 Z (1225 local) -2.8 degC (27 degF)
winds 20 knots from S on station 090

Juan Botella's photo of a mooring recovery, co-chief Alex Orsi is on the left, mooring expert Jim Ryder is left of center, and RPSC marine tech Barry Bjork is on the right.

We had a different sort of week than just one CTD station after another. First we enjoyed a transit through all sorts of ice, dodging zones where heavy ice would significantly slow us down, with a gorgeous sunset and moonrise. Then it was time to recover two arrays of bottom-anchored instruments Alex deployed during February 2010.

When we reached the first mooring site, Alex and Woods Hole mooring expert Jim Ryder (we are most fortunate to have him on board with us for our mooring work) went right to work. The Captain brought the Palmer near the expected location as they tried to communicate with the mooring’s release devices. Alex and Jim received only a weak, partial answer so began a search pattern, learning that the releases were more than a mile away from where they had been set down – perhaps an iceberg dragged the mooring sometime during the year. It was then too dark to try to recover the mooring, so we did a short line of CTD stations overnight. In the morning the weather was too iffy for a mooring recovery, so we headed over to the second mooring, about 32 miles away, to try to verify its location. By then the weather was seriously deteriorating and so we were able to do no more than learn that it, too, had been dragged, more than two miles. Further work was impossible and so we headed into the ice pack to wait out an impressively ugly storm. With blocks of ice being tossed about the sea surface in 60-knot winds, thank goodness we were safe on a sturdy icebreaker! When conditions improved, we headed to the first mooring site (the closest), where Jim and his team from the ship (our marine techs and the graduate students) recovered the mooring with few problems. Then we returned to the second mooring site, and in growing darkness its releases were acoustically triggered, and, voila, there was its blinking light beacon! The recovery was trouble free and Alex got back every instrument he deployed.

Mooring recovery in progress.

Readers who are oceanographers may be interested to note that during our lines of CTD stations at each mooring site we saw water at several hundred meters depth that was colder than the freezing point at the sea surface.  This can take place when cold water circulates and is cooled under floating, very deep reaching Antarctic ice shelves.

We then had a long steam to the start of our next line of CTD stations during which the students and a couple of other helpers dropped XBTs every 30 minutes over the day and a half transit.

Cruise plan adjustments were at the top of our agenda this week. We get great advice from scientists ashore, but in the end it is our
responsibility to manage the cruise. We started with a good plan and are keeping with it to every degree feasible. On the plus side, the station work is going great and we are spending less time in the ice than we thought we might when we planned the cruise. On the minus side we have lost more than 7 days to bad weather. The cruise to date included work of such high scientific priority that we felt compelled to complete it as planned, without reduction, and waiting out bad weather. But now as we begin the second half of this long cruise, we have decided to allot specific amounts of time to each remaining segment of the cruise except for a few “must complete, no matter what” activities. This is one way to get around the unknowns. The Captain is happy to work in a somewhat similar manner: within proper maritime limits he can allocate fuel in a cruise-segment manner roughly similar to our allocation of time. (As nearly all of you know, the ship uses far more fuel breaking ice than traversing open water, and also burns significantly more going, say 11 knots than 9 knots in open water.)

Both of us plan when and where we will apply our resources and where we will hold reserves. We have thus determined that we will have a go at the south-to-north line of stations along 170°W we had been prepared to cut just days ago. We allocated sufficient time to do 8 stations with average 43-mile spacing (but positioned to hit the deeper channels), and we will complete as much of it as the weather permits. Our section across the Ross Sea slope just NW of the major shelf channels has captured cold, fresh, high-oxygen bottom waters of shelf origin on the slope. The coming stations will track this water into the deep interior of the Ross Sea. Then we will move on to the next segment.

Sea bird seems to skate during take-off.

We are fortunate to be able to work with this superb team of technical specialists, with our enthusiastic students, with the expert captain, mariners, engineers, and support staff Edison Chouest Offshore provides on the Nathaniel B. Palmer, and with our experienced group from Raytheon Polar Services.

All is well on the Nathaniel B. Palmer.

Jim and Alex

Sunset and ice, photo by Jim Swift.

Thursday, 23 March 2011, 2135 local time
74°S, 173.5°W -1.6 degC / 29 degF
wind 24 knots from SW en route to station 84

Dear Family, Friends, and Colleagues,

We’ve had a different sort of week than just one CTD station after another. First we enjoyed a thrilling transit through all sorts of ice, dodging zones where  heavy ice would significantly slow us down, with a gorgeous sunset and moonrise.  Then it was time to recover two vertical arrays of bottom-anchored instruments co-chief scientist Alex Orsi deployed during February 2010.

Each instrument cable was anchored to a heavy weight on the bottom, with subsurface floats pulling the cable taut, instruments were attached to the cable,  and an “acoustic release” connects the cable to the anchor weight. In the following paragraph note that to recover a mooring you must first find it (none of it is at the surface while it is deployed), and you must be able to communicate with the release device (done with coded acoustic signals). If those are both successful (by no means guaranteed), you need daylight and reasonably good weather to recover it, which means in statistical terms less than 50% of the time on this cruise. Of course, the long line of instruments will hopefully rise to the sea surface after the acoustic release has been told to let go from the anchor, and you have to be able to see it – not as easy as you might think.  And on top of that, you need to be careful when you grab it and haul it in.

When we reached the first of the mooring sites, Alex and Woods Hole mooring expert Jim Ryder (we are most fortunate to have him on board with us for our mooring work) went right to work. Thanks to GPS, they knew where the first string of instruments was supposed to be. The Captain brought the Palmer near that point and they tried to communicate with the mooring’s release devices, but received only a weak, partial answer. After working the ship through a search pattern, stopping every now and then to try again, they learned that the releases were more than a mile away from where they had been set down – perhaps an iceberg dragged the mooring sometime during the year. Trouble was, it was now too dark to try to recover the mooring. So we did a short line of CTD stations overnight. In the morning the weather was too iffy for a mooring recovery, so we headed over to the second mooring, about 32 miles away, to try to verify its location. By then the weather was seriously deteriorating and so we were able to do no more than learn that it, too, had been dragged, more than two miles. Further work was impossible and so we headed into the ice pack to wait out an impressively ugly storm. With blocks of ice being tossed about the sea surface in 60-knot winds, thank goodness we were safe on a sturdy icebreaker! When conditions improved, we headed to the first mooring site (the closest), where Jim and his team from the ship (our marine techs and the graduate students) recovered the mooring with few problems. Then we returned to the second mooring site, and in growing darkness its releases were acoustically triggered, and, voila, there was its blinking light beacon! The recovery was trouble free and Alex got back every instrument he deployed.

Oceanographers reading this may be interested to note that during our lines of CTD stations at each mooring site we saw water at several hundred meters depth that was colder than the freezing point at the sea surface. This can take place when cold water circulates and is cooled under floating, very deep reaching Antarctic ice shelves. This was the first time I had observed such water myself.

Moonrise, photo by Juan Botella.

We then had a long steam to the start of our next line of CTD stations. Alex brought along several cases of eXpendable BathyThermographs (XBTs), small disposable instruments which provide a temperature profile from a moving ship. The students and a couple of other helpers dropped XBTs every 30 minutes over the day and a half transit.

My chief responsibilities with respect to a research cruise have to do with (a) preparing a cruise plan ahead of the cruise, (b) seeing that an appropriate team with its equipment is put in place to carry out the plan, (c) monitoring progress at sea, and then (d) modifying the plan as or if needed. With respect to (a), I am guided by world class experts such as Alex Orsi, Kevin Speer (at Florida State University), Stan Jacobs (at Columbia University), and the members of the science oversight committee for the US Global Ocean Carbon and Repeat Hydrography program – plus many others – so that goes well. Item (b) is easy with this team: I am honored to be able to work with these technical specialists, with the expert captain, mariners, engineers, and support staff Edison Chouest Offshore provides on the Nathaniel B. Palmer, and our experienced group from Raytheon Polar Services. Item (c) sort of takes care of itself since we keep records of, well, everything. Then there is (d). I remind myself that “if it was a good plan ashore it is still a good plan at sea”. But what do I do when, by my accounting, we have already lost 7 full days due to bad weather? Yet, some other aspects – the station work and time slowed down in ice in particular – have gone remarkably well in our favor. I listen to good advice, and make a decision.

The cruise to date included work of such high scientific priority that I felt compelled to complete it as planned, without reduction, waiting out weather. But now as we begin the second half of this long cruise, I have decided to allot specific amounts of time to each remaining segment of the cruise except for a few “must complete, no matter what” activities. This is one way to get around the unknowns. The Captain is happy to work in a somewhat similar manner: within proper maritime limits he can allocate fuel in a cruise-segment manner roughly similar to my allocation of time. (The ship uses far more fuel breaking ice than traversing open water, and also burns significantly more going, say 11 knots than 9 knots in open water.) Both of us plan when and where we will apply our resources and where we will hold reserves.

I have thus determined that we will have a go at a south-to-north line of stations along 170°W I had been prepared to cut just days ago. I allocated sufficient time to do it, and we will complete as much of it as the weather permits. Then we will move on to the next segment. But no rushing, no change in the way we work. I’ll let you know how this goes!

All is well on the Nathaniel B. Palmer.

Jim Swift
Chief Scientist
NBP-1102 / S04P

Penguins form a parade.

On our first Thursday, March 17th (see below for explanation) we finished our planned line of stations 525 nautical miles straight south from 67°S (roughly the Antarctic Circle) to the Antarctic continental shelf, stopping every 30 miles to make measurements. This completes for the first time the southern end of a long transect of oceanographic measurements extending from Kodiak Island, Alaska, to Antarctica, known to oceanographers as “line P16″. This also completes a key portion of our intended work on this cruise, though there is a great deal more work to do. Data quality remains excellent, and all systems are working well, except that one of the two lowered Acoustic Doppler Current meters (LADCP) is out of service, limiting LADCP profiles now to downward-looking only.

See the figure, and its caption below, from Alex for a discussion of some of the scientific findings apparent when comparing the 2011 data with those from earlier years. We have all enjoyed the good weather. The last group of 5 closely-spaced stations were carried out in highly varied and increasingly more impressive ice ranging from the smallest newly-formed frazil ice that “greases” the sea surface, to new “pancake ice” of various sizes (very easy going), to first (easy) and multi-year (try to avoid) sea ice, to impressively thick pieces of broken off ice shelf (impossible), to mighty icebergs (likewise). The Palmer’s mates and our expert ice pilot Vladimir Repin enjoy the challenge of guiding the ship through the maze of ice day and night. The Nathaniel B. Palmer’s large bridge has great all-around views and is The Place To Be when one has a bit of time off, though the weather has been so good that some have bundled up and to watch icebreaking from the bow or other points outdoors on the ship. The ice and icebergs provide many photo opportunities and we frequently come across penguins and basking seals.

We are at the edge of the footprints of both of the geosynchronous INMARSAT satellites (one over the Atlantic equator and the other over the Pacific equator) that provide our primary email communications, so email may continue to be a bit sporadic until we head back north to the S04P line at 67°S. Although we did our date line crossing some time ago we saved our day/date change to celebrate St. Patrick’s Day (Thursday, March 17th) twice on the ship.

Our cruise is now approximately at its half-way point. We are steaming toward the sites where we will recover two strings of moored instruments co-chief scientist Alex Orsi deployed February 2010. We will then resume our CTD work with our third crossing of the Antarctic continental slope. Weather has been good to outstanding most of the past week, and during our few days in the ice all hands enjoyed the wildlife and highly-varied ice. New ice is forming around us, with grease ice consolidating in sheets and pancakes. Meanwhile we motor around magnificent icebergs and slab-like chunks of shelf edge ice.

We continue to enjoy working with our team at sea. This may be a very long cruise but with this team it is a productive and happy one. The entire ship’s company continues to work with expertise, efficiency, and good cheer. All is well aboard the Nathaniel B. Palmer.

We have included Nancy Williams’ photo of an iceberg at sunset and Wilson Mendoza’s photo of a group of Adelie penguins.

Ice takes the shape of shelves, pancakes and tables

Jim and Alex

a) Location map with stations occupied during the 2011 S04P repeat (red) and in previous cruises (blue) of 1992 (WOCE), 2005 (CLIVAR) and 1994 (N.B.
Palmer); b) synoptic vertical section of potential temperature (°C) on CLIVAR S04P 2011; and c) on a multiyear composite from the older
hydrography.

Data from the just completed Antarctic coast-bound transect enclosing the southwestern Pacific Ocean, partly due to unprecedented spatial and temporal resolution, reveal a series of mesoscale to large-scale circulations.  A southwestward loop of the Antarctic Circumpolar Current is found across the southern half of the 150°W line.  Significantly warmer source Lower Circumpolar Deep Water (LCDW) now enters the interior subpolar
cyclones found around the Balleny Islands and to the south of the Southwest Pacific Ridge.   Prominent westward flow associated with the Antarctic Slope Current is revealed just upstream and downstream of the Ross Sea, near Cape Colbeck and Cape Adare.  The Antarctic Surface Water (AASW) carried farther inshore has cooled and freshened over time between the repeat hydrography.  Evolving characteristics in the LCDW, AASW and Shelf Water mixtures outflowing the Ross Sea are evident in the deep and bottom layers of the S04P line.  E.g. on average the AABW recirculating below 3000 m in this region has increased its temperature by about 0.1°C.

Cheers,

Alex

The storm which stopped our work last Thursday morning finally abated early Saturday. Since then we have been working steadily on our measurement program, without weather or equipment delays. We are making good progress, though remain about 5 days behind the expedition deadline timeline. Small problems pop up in the equipment from time to time, and we have found some ways to improve a few procedures – pretty much business as usual. Data quality remains excellent. No surprise that the Circumpolar Deep Water and its closest relatives remain consistently warmer and slightly saltier than observed during the Akademik Ioffe S04P cruise in 1992.

We will soon turn from our eastward course and follow 150°W south to the Antarctic continental shelf, which will complete for the first time the far south end of WOCE/CLIVAR/IOCCP line P16. Then it will be decision time for the first cuts to the science program. The Palmer is steaming mostly at 9 knots to conserve fuel, and has quite understandably had to slow in fog at night in waters where there are hazardous growlers and bergy bits that do not show up on the radar. Not to mention that there is plenty of stormy weather out there, just missing us at the moment. Because we can make up four days simply by widening station spacing to 60 nmiles on the eastern half of the 67°S (S04P) section, we are not in an insurmountable situation regarding the present time deficit, but we are still considering a 3-day cut (the sampling along 170°W, from 73°S to 67°S), which has been discussed with the oversight committee and team PIs. Watch for next week’s report for our decision.

Aura by Juan Botella.

Small breaks provided by nature the past week include icebergs (the reliable scenic highlight of working near Antarctica), the Aurora Australis a few times (we’ve included two photos shot by Juan Botella, our PolarTREC teacher), and a close-up visit by a few humpback whales (see the previous post).

The galley staff is great at keeping morale (and waistlines) at a maximum. Fresh bagels made a surprise appearance, the cookie supply seems endless, the meal entrees are as tasty and varied as ever (with some excellent vegetarian dishes, too). No one is surprised that the fresh vegetable supply is dwindling – lettuce is gone now, for example.

We have not yet accounted for the date line in our current ship’s day/date, so enjoy the odd situation of now being on the same time zone as Hawaii, but one day ahead. We have not yet changed day/dates mostly due to our plan to go back to 180°W to start a cross-shelf section after we complete the 150°W section and two mooring recoveries, though I confess that the notion of switching one week from today – thus having two March 17th’s (St. Patrick’s days) – may have entered our minds.

This is a harmonious, very good natured bunch. Cribbage and foosball tournaments are in full swing, groups linger at meals to enjoy
conversations, music is heard from time to time. All is well aboard the Nathaniel B. Palmer.

Jim and Alex

The aurora borealis hangs a filmy curtain with the Southern Cross behind it.

Some amazing photos from the southern oceans. Those of us who stay at home in warmer, dryer climates often think of the polar regions as stark and bare – but in fact the southern oceans teem with life and breath taking images. Alex sent these photos today for us.

Humpback displays fluke (tail) during a dive.

Humpback whales