Purdue Climate Change Research Center

The Collaborative O-Buoy Project: Deployment of a Network of Arctic Ocean Chemical Sensors for the IPY and Beyond

Funded by the National Science Foundation

The Arctic Ocean is a rapidly changing and hostile environment: remote and, at times, inaccessible; air temperatures as low as -50oC; months of darkness; a sea ice cover that is constantly moving and deforming; pervasive moisture during the melt season; drifting snow and marauding mammals. These conditions make any observation difficult, but pose particular difficulties for autonomous sensors.

To date, most long-term Arctic atmospheric observations, in particular, most chemistry data, have been collected on land, although the Arctic Ocean and its sea ice cover modify the climate and atmospheric composition of the entire region. It is known that surface chemistry involving sea salt results in destruction of ozone (O3) and elementary mercury (Hg) at the surface during spring time in the Arctic. However, due to the logistics challenge of long term measurements, there have been very few such measurements of O3 or other chemical species in the atmosphere above the Arctic Ocean surface (except from satellites and aircraft). Long-term, ocean-based atmospheric data sets are needed to quantify seasonal and interannual variability in a fast changing ice field that will vary in different regions of the Arctic Ocean.

It is essential that this capability is developed now so that the appropriate measurements can be made as the physical nature of the Arctic Ocean surface changes in relation to climate change.

The Arctic Ocean is central to the understanding of climate and global environmental change. As a critical component of the Earth system, the Arctic region both influences and responds rapidly to natural variations and to human-induced perturbations such as warming, contaminant accumulation, and their associated impacts.

While it is clear that dramatic changes are occurring in the Arctic, recent observations show that sea ice area is currently decreasing much faster than models are able to simulate. This raises important questions about feedbacks not only in terms of heat budgets, but in terms of atmospheric composition and chemistry. It is known that in springtime in the Arctic, natural photochemical processes, initiated by saline sea ice surfaces, result in the complete removal of ozone from the lower atmosphere. In a sea-ice free Arctic, this process would no longer occur, resulting in potentially significant impacts on the biosphere that "turns on" in the spring. Changes in these processes may also create changes in aerosols, and thus cloud cover. It is critically important that we understand feedbacks between sea, atmospheric composition, and climate.

PCCRC Director Paul Shepson and collaborators are now working on two large scale projects as part of OASIS-IPY. One is called the "O-Buoy Project." The research team will develop and then deploy a number of Arctic Ocean buoys in the sea ice at various locations around the Arctic Ocean to measure CO2, O3, and reactive halogen species that destroy ozone. These buoys will enable analysis of the relationships between sea ice cover and the chemistry that occurs at the interface between the ocean and the atmosphere, and enable access to data that has never previously been obtained.

At the same time that the O-Buoys will be deployed, a large scale field study will be conducted in Barrow, Alaska and from an ice camp in the Beaufort Sea, as part of OASIS2009. The field study will involve researchers from around the world (20 different countries are involved) collaborating on flux measurement of gases (such as mercury, which is oxidized by the same species that destroy ozone) between the sea ice/snowpack surface and the atmosphere. This will be the first time that a comprehensive study of atmospheric chemistry above the sea ice has been conducted.

International Polar Year (IPY), organized through the International Council for Science and the World Meteorological Organization (WMO), is currently convening the fourth polar year, following those in 1882-3, 1932-3, and 1957-8.

Investigator(s)

  • Paul Shepson, Chemistry
  • P. Matrai, Bigelow Laboratory
  • J. Bottenheim, Environment Canada
  • U. Frieß, University of Heidelberg
  • D. Perovich, CRREL
  • W. Simpson, University of Alaska, Fairbanks

Contact Information

Purdue University
PCCRC
203 S. Martin Jischke Drive
MANN 105
West Lafayette, IN 47907