Climate-driven changes to the atmospheric CO2 sink in the subtropical North Pacific Ocean.
The oceans represent a significant sink for atmospheric carbon dioxide. Variability in the strength of this sink occurs on interannual timescales, as a result of regional and basin-scale changes in the physical and biological parameters that control the flux of this greenhouse gas into and out of the surface mixed layer. Here we analyse a 13-year time series of oceanic carbon dioxide measurements from station ALOHA in the subtropical North Pacific Ocean near Hawaii, and find a significant decrease in the strength of the carbon dioxide sink over the period 1989-2001. We show that much of this reduction in sink strength can be attributed to an increase in the partial pressure of surface ocean carbon dioxide caused by excess evaporation and the accompanying concentration of solutes in the water mass. Our results suggest that carbon dioxide uptake by ocean waters can be strongly influenced by changes in regional precipitation and evaporation patterns brought on by climate variability.
Dore
John E
JE
Department of Oceanography, School of Ocean and Earth Science and Technology, University of Hawaii, 1000 Pope Road, Honolulu, Hawaii 96822, USA. jdore@hawaii.edu
Lukas
Roger
R
Sadler
Daniel W
DW
Karl
David M
DM
D001272:Atmosphere; D002245:Carbon Dioxide / Q000378:metabolism*; D002980:Climate; D005740:Gases / Q000378:metabolism; D006254:Hawaii; D010140:Pacific Ocean; D010313:Partial Pressure; D011891:Rain; D012621:Seasons; D012965:Sodium Chloride; D013696:Temperature; D013816:Thermodynamics; D013997:Time Factors; D014329:Tropical Climate
D005740:Gases; D002245:Carbon Dioxide; D012965:Sodium Chloride