FY 2011
Deep circulation and meridional overturning: Recent progress and a strategy for sustained observations
Rintoul, S. R., M. Balmeseda, S. Cunningham, B. Dushaw, S. Garzoli, A. Gordon, P. Heimbach, M. Hood, G. Johnson, M. Latif, U. Send, C. Shum, S. Speich, and D. Stammer
In Proceedings of the "OceanObs'09: Sustained Ocean Observations and Information for Society" Conference (Vol. 1), Venice, Italy, 21–25 September 2009, Hall, J., D.E. Harrison, and D. Stammer, Eds., ESA Publication WPP-306, doi: 10.5270/OceanObs09.pp.32 (2010) |
| The global overturning circulation (OC) and its deep branch strongly influence phenomena of direct interest to society, including climate change and variability, sea level, temperature and rainfall patterns over land, global biogeochemical cycles and marine productivity. Observations of the deep ocean remain scarce, limiting our ability to understand and predict the overturning and deep circulations, their response to changes in forcing, and the impact of changes in the deep ocean on marine ecosystems, biogeochemical cycles and global climate. However, substantial progress has been made in recent years, including quantitative estimates of the strength of the global overturning circulation; the first time series measurements of the Atlantic meridional overturning circulation; evidence for changes in temperature, salinity and carbon in the deep ocean; and a deeper understanding of the role of the deep ocean and OC in low-frequency climate variability. These advances provide a guide to the design and implementation of a sustained observing system for the deep ocean and OC. We outline a strategy for sustained observations of the deep ocean that begins with tools available now, primarily repeat hydrography and moored arrays spanning deep boundary currents, key passages, and ocean basins where feasible. New technologies - including profiling floats and gliders capable of sampling the full ocean depth, long-duration moorings with data telemetry, and new sensors - are needed to complete a comprehensive observing system for the deep ocean. |
