Award: PLR-1220032

This project collected and analyzed data to create a high-resolution dataset for baseline chemical monitoring from the Arctic Ocean. Data collected were aimed at monitoring changes in ocean acidification of surface waters and their saturation with respect to the mineral aragonite, which is important for organisms that use aragonite in their skeletal material. Ocean acidification is the process by which seawater becomes increasingly acidic (lower pH) due to greater amounts of carbon dioxide being absorbed by the oceans from the atmosphere. Currently Earth's oceans absorb about one-fourth of the carbon dioxide produced by human activities. However this process is not homogenous across Earth's oceans and the Arctic may play an important but relatively poorly understood role in global ocean acidification. Such variation of ocean surface water pH affects species up and down the food web. Laboratory studies have shown that more acidic water decrease the rates at which many organisms build skeletal materials from aragonite. Data produced by this project have shown an area of aragonite undersaturation that now covers approximately 20% of the surface area of Canadian Basin--a situation that has until recently has not been the norm. This area of undersaturation has been previously recognized, but relatively undefined. In addition to monitoring the baseline of acidification in the Arctic Ocean, this project has also used water-source tracer data which link the undersaturation to the processes of sea-ice melt and to terrestrial runoff from rivers in addition to the uptake of anthropogenic carbon dioxide from human activity. These data are important because they demonstrate unprecedented rates of change that extend beyond model projections and the average rate of change in the global ocean. These data will be critical in gauging future changes in the region, particularly in areas where extensive sea-ice melt has not yet occurred. Last Modified: 10/30/2015 Submitted by: Jonathan G Wynn