Advancing our knowledge of the Ocean Carbon Cycle

Advancing our Understanding of the Role of the Ocean Carbon Cycle
Investigating the links between carbon dioxide, the ocean and the world's changing climate
In the 1980's, scientists became increasingly aware of the importance of ocean circulation and the cycling of elements such as carbon, nitrogen and oxygen as regulators of Earth's climate. At the same time, concerns were growing about the potential for significant global warming from increased levels of greenhouse gases (e.g., carbon dioxide and other gases) released into the atmosphere by the burning of fossil fuels. In response, two major international oceanographic research programs were initiated to study the relationship between the ocean, carbon dioxide and climate: the World Ocean Circulation Experiment (WOCE) and the Joint Global Ocean Flux Study (JGOFS).
Figure 1. Atmospheric CO2 levels over the last 1000 years (Sarmiento and Gruber, 2002)
Continuing concern about climate change has been accompanied by growing scientific awareness of the complexity of the Earth's climate. The last decade has been judged the warmest in recorded history, and there is increasing evidence that temperatures will continue to rise for the foreseeable future.
Figure 2. Global mean temperatures over the last 1000 years.
In the 1980's, BIOS was poised to contribute to studies of global climate and carbon. By 1987, the long-term oceanographic time series Hydrostation "S" had collected 43 consecutive years of information about the structure and variability of ocean temperature and salinity off Bermuda. This data set, and Bermuda's mid-ocean location, made Bermuda the prime choice as the site of an expanded oceanographic time series studying ocean physics, chemistry and biology. In October 1988, a research cruise aboard the R/V Weatherbird I began a comprehensive oceanographic time-series program, the Bermuda Atlantic Time-series Study (BATS). This program has not only changed and greatly expanded BIOS; it has, even more significantly, made a substantial contribution globally to changing scientific views about how the ocean and climate system operates. Temperature data collected at Hydrostation "S" and BATS have documented a rise in ocean temperatures in response to changes in the atmosphere. These data have provided a new understanding about global ocean circulation, seasonal and year-to-year ocean variability, and the complex interactions between the ocean and climate.