How's That Data Rolling In?
September 29, 2008
The other day I received an update on seismic data collection (used for mapping the sub-seafloor) from USGS geophysicist Jonathan Childs, chief scientist for Healy. I asked him about the quality of our incoming data, whether the systems have been working smoothly, and what the plans are after we depart Healy and Louis.
Before embarking, there were several objectives and expectations for this trip. We have exceeded expectations in terms of our ability to move through the sea ice and the reliability of our equipment. Both the U.S. and Canada have been extremely successful in collecting seismic data. We have had no down time on Healy and have been collecting data every moment our ship was moving. The Canadians were able to keep their instruments in the water for up to 72 hours at a time, which is a significant accomplishment given the surrounding ice-covered conditions.
Geographically, we have reached several points scheduled for data collection, but some areas were too heavily covered with sea ice, and we were not able to break through. For example, we hoped to get closer to Canadian islands, but unfortunately the sea ice was too thick. However, pre-cruise plans are always optimistic, so these minor obstacles were not disappointing. You can’t really predict the conditions you will face and how things will fare.
After a preliminary review of incoming seismic data, scientists onboard have observed several fascinating features beneath the seafloor. Once this expedition is complete, data will be formally analyzed and interpreted. Analysis will include further interpretation of sediments, sedimentary thicknesses, and how plates moved to form the basins and underwater seafloor elevations. Scientists will also assess where additional data are needed to help clarify these geologic interpretations.
In addition to the seismic data, the other research onboard has been very successful. In regards to water sampling to study microorganisms in the Arctic Ocean, positive results have already been achieved. The proportions of the organisms being studied (mixotrophs) are similar to those recently observed in the Antarctic. At this point, samples have been collected from several depths at nine different locations and we expect to gather at least one more sample in the last couple days of our journey.
Four open ocean drifting buoys, which move with the current, were deployed before our science crew’s time on Healy began. There are six more available for deployment as we move out of the ice pack and go southbound to Barrow, Alaska. These buoys, or drifters, provide location, air pressure and temperature, and water temperature. The buoy data are transmitted through the Argos satellite network and help us track and understand ocean circulation, atmospheric conditions, and the future production and distribution of sea ice. Drifting buoys like these will be increasingly used in the Arctic as open ocean areas expand. The buoys are being deployed as part of the International Arctic Buoy Programme by Pablo Clemente-Colón, Chief Scientist of the National Ice Center and an oceanographer with NOAA.
We are still collecting data, so all further progress will build on what has already proved to be a very successful cruise.
Until next time,