The Arctic Ocean, covering an area of over 14,056,000 km2, may be one of the world's oceans most vulnerable to climate change. With a fairly constant water temperature of 0°C, the Arctic has the ability to absorb carbon dioxide more readily than warmer waters. Ocean acidification may be occurring faster at the poles than other climate regions for several reasons:
Cold water more readily absorbs CO2, lowering the pH,
Added melt-water and increased riverine input is forcing additional uptake of CO2,
Reduced sea-ice coverage results in more seawater exposure to and uptake of atmospheric CO2, and
Expanded ocean-surface area may in turn alter the production and decomposition of organic carbon, a complex process that plays an important role in ocean chemistry.
Our data from 2010 and 2011 cruises show large areas of the Canada Basin which are already undersaturated with respect to aragonitea shell forming mineral important to growth and survival of important food web organisms, like pteropods.
The U.S. Geological Survey (USGS) is working with partners to measure baseline seawater chemistry of the Arctic Ocean and to improve understanding of ocean acidification in polar regions.
August 2012 Cruise
Back for a third time on the Healy, the USGS and USF scientists are returning to gather information to the west of the previous track lines, over the Chukchi Cap and into the Nautilus Basin. Follow us on this years' cruise where we are collecting:
The USGS and USF scientists returned to the Arctic in August 2011 to gather more baseline data- The Healy traveled even further north than the previous yearas far as the Makarov Basin (about 88° 44N). This expedition has provided a comparison of ice free water with that of 100% ice cover. Read more about the 2011 Arctic Cruise.
In August 2010, USGS and University of South Florida (USF) researchers sampled the Canada Basin during the 2010 U.S.-Canada Extended Continental Shelf Survey research expedition on board the U.S. Coast Guard vessel Healy. Water samples included:
Underway data taken by the Multiparameter Inorganic Analyzer (MICA), resulting in an unprecedented +25,000 records of pCO2, pH, and total carbon data.
Discrete water samples taken every 2 hrs throughout the cruise and analyzed aboard the Healy for pH, alkalinity, and carbonate [CO3-2].
240 discrete samples that were analyzed back on land for carbon and oxygen isotope, nutrients, and metals.
Water from nine water column casts using a Rosette sampler; samples were taken from water as deep as 3500 m.
Preliminary data were presented at different symposia, with 3D views of the Canada Basin carbon parameters demonstrated on a tablet computer mounted to the posters. In particular, the data show the quality and high-resolution spatial information that this unique dataset provides.
Trackline of August 2010 cruise.
Synoptic view of the data shows a line over 9,400 km long; zooming into an area, data points taken every two minutes are revealed. [larger version]
Symposium participants stopped by to see the 3D model of Arctic ocean chemistry. [larger version]