Natural Variability and Anthropogenic Trends in the Ocean Carbon Sink.
Since preindustrial times, the ocean has removed from the atmosphere 41% of the carbon emitted by human industrial activities. Despite significant uncertainties, the balance of evidence indicates that the globally integrated rate of ocean carbon uptake is increasing in response to increasing atmospheric CO2concentrations. The El Niño-Southern Oscillation in the equatorial Pacific dominates interannual variability of the globally integrated sink. Modes of climate variability in high latitudes are correlated with variability in regional carbon sinks, but mechanistic understanding is incomplete. Regional sink variability, combined with sparse sampling, means that the growing oceanic sink cannot yet be directly detected from available surface data. Accurate and precise shipboard observations need to be continued and increasingly complemented with autonomous observations. These data, together with a variety of mechanistic and diagnostic models, are needed for better understanding, long-term monitoring, and future projections of this critical climate regulation service.
Department of Atmospheric and Oceanic Sciences, Center for Climatic Research, and Space Science and Engineering Center, University of Wisconsin-Madison, Madison, Wisconsin 53706; email: gamckinley@wisc.edu , arfay@wisc.edu.
Galen A
GA
McKinley
Department of Atmospheric and Oceanic Sciences, Center for Climatic Research, and Space Science and Engineering Center, University of Wisconsin-Madison, Madison, Wisconsin 53706; email: gamckinley@wisc.edu , arfay@wisc.edu.
Amanda R
AR
Fay
Department of Atmospheric and Oceanic Sciences and Institute of Arctic and Alpine Research, University of Colorado Boulder, Boulder, Colorado 80309; email: nicole.lovenduski@colorado.edu.
Nicole S
NS
Lovenduski
Pacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, Washington 98115; email: darren.pilcher@noaa.gov.
Darren J
DJ
Pilcher
D001272:Atmosphere; D002245:Carbon Dioxide; D057965:Carbon Sequestration; D059000:El Nino-Southern Oscillation; D009792:Oceans and Seas
D002245:Carbon Dioxide
North Atlantic; North Pacific; Southern Ocean, Earth system model large ensemble; equatorial Pacific; global carbon cycle; ocean carbon sink