Evaluation of the net CO 2 uptake in the Canada Basin in the summer of 2008
- PDF / 1,435,385 Bytes
- 7 Pages / 595 x 842 pts (A4) Page_size
- 44 Downloads / 196 Views
Evaluation of the net CO2 uptake in the Canada Basin in the summer of 2008 SUN Heng1, GAO Zhongyong1*, LU Peng2, XIU Peng3, CHEN Liqi1 1 Key Laboratory of Global Change and Marine Atmospheric Chemistry of State Oceanic Administration, Third
Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China 2 State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China 3 State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of
Sciences, Guangzhou 510301, China Received 31 July 2016; accepted 28 September 2016 ©The Chinese Society of Oceanography and Springer-Verlag Berlin Heidelberg 2017
Abstract
The third Chinese National Arctic Research Expedition (CHINARE) was conducted in the summer of 2008. During the survey, the surface seawater partial pressure of CO2 (pCO2) was measured, and sea water samples were collected for CO 2 measurement in the Canada Basin. The distribution of pCO 2 in the Canada Basin was determined, the influencing factors were addressed, and the air-sea CO2 flux in the Canada Basin was evaluated. The Canada Basin was divided into three regions: the ice-free zone (south of 77°N), the partially ice-covered zone (77°–80°N), and the heavily ice-covered zone (north of 80°N). In the ice-free zone, pCO2 was high (320 to 368 μatm, 1 μatm=0.101 325 Pa), primarily due to rapid equilibration with atmospheric CO2 over a short time. In the partially ice-covered zone, the surface pCO2 was relatively low (250 to 270 μatm) due to ice-edge blooms and icemelt water dilution. In the heavily ice-covered zone, the seawater pCO2 varied between 270 and 300 μatm due to biological CO2 removal, the transportation of low pCO2 water northward, and heavy ice cover. The surface seawater pCO2 during the survey was undersaturated with respect to the atmosphere in the Canada Basin, and it was a net sink for atmospheric CO2. The summertime net CO2 uptake of the ice-free zone, the partially ice-covered zone and the heavily ice-covered zone was (4.14±1.08), (1.79±0.19), and (0.57±0.03) Tg/a (calculated by carbon, 1 Tg=1012 g), respectively. Overall, the net CO2 sink of the Canada Basin in the summer of 2008 was (6.5±1.3) Tg/a, which accounted for 4%–10% of the Arctic Ocean CO2 sink. Key words: Canada Basin, net CO2 uptake, partial pressure of CO2 Citation: Sun Heng, Gao Zhongyong, Lu Peng, Xiu Peng, Chen Liqi. 2017. Evaluation of the net CO2 uptake in the Canada Basin in the summer of 2008. Acta Oceanologica Sinica, 36(8): 94–100, doi: 10.1007/s13131-017-1028-9
1 Introduction Although the Arctic Ocean only accounts for 4% of the world’s ocean surface area, it is an important potential sink for atmospheric CO 2 (Bates and Mathis, 2009). Recent studies showed that the Arctic Ocean contributed 5%–14% of the global oceanic CO2 sink (Bates and Mathis, 2009; Bates et al., 2011). The central basin of the Arctic Ocean has lower CO2 content than the atmosphere (Cai et al., 2010; Bates et al., 2011). At present, seasonal sea-ice
Data Loading...
