Research Engineer, Lamon-Doherty Earth Observatory of Columbia University
Airborne seawater sampling through Arctic sea ice
Wednesday — February 19, 2014
Pacific Forum — 3:00 p.m.
While modern remote sensing technology provides measurement capability for a number of seawater properties, there are important measurements that can not yet be done remotely so physical water samples carefully collected and returned to the lab remain essential. In the ice covered Arctic Ocean water samples are difficult to obtain from ships because of the extensive ice cover and thick pressure ridges. Aircraft have been used for sampling the Arctic Ocean for the past half-century using bottles at pre-selected depths and internally recording CTDs lowered through leads or holes drilled in the ice. Traditional CTD/rosette technology used for sampling from ships are too heavy and bulky to deploy from ice-capable aircraft. We have developed a lightweight modular system that is deployed through a 12-inch (30cm) hole in the ice. Real-time CTD traces are displayed on a laptop and the bottles are tripped at selected depths using modified Seabird hardware and a Lamont-developed bottle tripping system. The Switchyard project has sampled a line of stations in the heavily ice covered Lincoln Sea region between Alert and the North Pole for ten seasons. For Switchyard, we routinely measure salinity, oxygen, nutrients, tritium, helium isotopes, CFCs, SF6, oxygen isotopes, barium, PCO2 and I-129 but other analysis are also feasible.
Next: March 5 - Fred Whoriskey