AGE OF CANADA BASIN DEEP WATERS - A WAY TO ESTIMATE PRIMARY PRODUCTION FOR THE ARCTIC-OCEAN

An empirical model of carbon flux and C-14-derived ages of the water in the Canada Basin of the Arctic Ocean as a function of depth was used to estimate the long-term rate of primary production within this region. An estimate can be made because the deep waters of the Canadian Basin are isolated from the world oceans by the Lomonosov Ridge (sill depth about 1500 meters). Below the sill, the age of the water correlates with increased nutrients and oxygen utilization and thus provides a way to model the average flux of organic material into the deep basin over a long time period. The C-14 ages of the deep water in the Canada Basin were about 1000 years, the carbon flux across the 1500-meter isobath was 0.3 gram of carbon per square meter per year, and the total production was 9 to 14 grams of carbon per square meter per year. Such estimates provide a baseline for understanding the role of the Arctic Ocean in global carbon cycling.