We Blogged It!
January 16, 2011
Chief Scientist Tish Yager has sent her last weekly report as they wait to reach the Ice Pier at McMurdo:
“…We have completed the 7th and final week of our 52-d expedition. The Oden spent the past few days clearing the channel through the fast ice to McMurdo and is now at the ice pier, offloading cargo and samples for the USAP scientists. We will follow shortly… “
“We started the week by finishing our last ASPIRE station near a trough at the shelf break, not far from where we first entered the region about a month ago. A day/night MOCNESS pair, combined with a full daily station, gave us a good indication of seasonal changes in the waters connecting the polynya region to the deep ocean to the northwest. The zooplankton samples revealed a very different suite of animals in this region (compared to the polynya), causing us all to wonder further about the connection between the open sea and the polynya. We also had time between MOCNESS's for repeated vertical net tows of live zooplankton for experiments investigating the relationship between zooplankton and bacteria, and a snow sample collection by the Aldahan team using the manbasket. Science operations were completed by 03:00 on January 9th, and we then began our long steam toward the Ross Sea and McMurdo Station.”
“Though we had hoped to leave ourselves enough time for ancillary science operations in the Ross Sea, the physical environment reminded us yet again that it determines what can be done here in Antarctica. We experienced overcast skies and snow with very low visibility. Also, the floes that seemed loose and unconsolidated on the ice images were instead highly dynamic and difficult to predict. Thus, we steamed around the western Getz Ice Shelf and into the Ross Sea much slower (5-6 kn) than we expected to, arriving at 150° W during the early morning hours of January 12. From there we had approximately 700 nm of open water to transit, with just a little more than three days to do it (recall that we would cross the dateline and lose a day). We decided to stay focused on the task at hand: getting to McMurdo on time.”
“ Underway sampling continued by the Aldahan (ocean and atmospheric tracers), Schofield (underway phytoplankton physiology and optics), and Jacobs (XBTs across the slope) teams as the rest of the team finished up processing of the week-long experiments started during our final long station on January 5. The Aldahan team was also able to collect snow samples that fell on the ship. This was fortunate since their underway air sampler had just failed after working well since it was acquired from the Oden in mid-December.”
“ As each team finished up their sample processing during the transit, packing up was the next priority, especially with samples and cargo needing to be entered into the electronic cargo system (MOCA) well in advance of our arrival at the pier. We also scheduled a series of science meetings to discuss our preliminary findings. When we all sat down to look at what we had done, there was some astonishment as well as a great deal of pride for our accomplishments. I think its fair to say that we set a high bar and reached it.”
“Outbrief meetings were also scheduled to discuss the effectiveness of ship and logistics support for the science. Overall, there was high praise for the support that science received during this expedition. We have a great team of people.”
“As it turned out, we made good time across the miles of open water and were able to devote an hour or so on the morning of January 15 (NZ time) to deploying the CTD at the times series station (77°10'S, 168° 20'E) near Ross Island. This location has been monitored fairly regularly over the past 50-years, and has shown a dramatic freshening of the Ross Sea over that time (Jacobs et al. 2002; Jacobs & Giulivi 2011). “
“ Following the CTD cast, we steamed toward the Oden's channel and began working our way toward the Ice Pier at McMurdo. The Oden's progress on the channel was delayed by heavier than expected fast ice, so we waited in the channel for them to finish.”
“At this writing, we are all still onboard the NBP, stationed just away from the Ice Pier, while Oden completes its cargo operations. We all greatly anticipate our first step onto the continent this afternoon, after watching it from afar for so many weeks. I understand from our Multibeam technician, Kathleen Gavahan, that we recorded 9510 km of multibeam bathymetric data on this cruise. We have come a long way!”
“ Lollie Garay has told our story via the AntarcticASPIRE.org website and she was pleased to report the great support and interest expressed so far (over 7400 hits on 32 blog posts to date). Thanks to Lollie for her great contribution.”
“…We are grateful to our colleagues, friends, and families back home who have made our long travels possible. We are truly impressed by this very fine research vessel, its outstanding captain and crew, and the highly talented RSPC support that enabled us to achieve and often exceed our science goals. The Amundsen Sea has fewer secrets this week.
With best wishes, Tish”
The images of this post were photographs taken and shared by Povl Abrahamsen in the channel at McMurdo Sound. I also erroneously gave Tish credit for his photos on yesterday’s blog and have made corrections! And, despite several pleas to the crew of the NBP and the science team, I have not yet received more photos of the crew working. Remember that the voyage was “jam packed” with work. I hope that someone will share their photos of the great crew we have heard so much about upon their return!
Question of the Day
- What are Polynyas and why are they important to study?
Polynyas, are recurring areas of seasonally open water surrounded by ice.
Energy and material transfer between the atmosphere, polar surface ocean, and the deep sea in polynas provide polar ecosystems with just the right ingredients needed for high productivity and intense biogeochemical recycling.
Polynyas may be the key to understanding the future of Polar Regions since their extent is expected to increase with anthropogenic warming.