南大洋二氧化碳源汇分布及其海-气通量研究

在 1 999年 1 2月 - 2 0 0 0年 2月“雪龙”号科学考察船往返于中山站和长城站期间 ,进行了大气及海表层 CO2 分压的连续测量。研究结果表明 ,在 80°W- 0°- 80°E之间 ,南大洋基本上是大气 CO2 的汇 ,尤其在 45°W- 3 0°W及 1 0°W- 1 0°E之间 ,是 CO2 的强汇区 ,往返的两次观测结果十分相似。观测发现 ,南大洋 1月份吸收大气 CO2 的能力近两倍于 1 2月份 ,这是由于该海域1月的生产力比 1 2月份高 ,因而反映了初级生产对大气 CO2 吸收的显著影响。利用最新的 K值计算方法表明 ,1月份二氧化碳的入海通量为 3 .98mol/(m2 · a) ,1 2月份的为2 .1 3 mol/(m2 · a) ,综合两个月的值平均 ,南大洋夏季 CO2 的平均通量为 3 .0 6 mol/(m2 · a) ,是南半球夏季一个重要的汇区

AIR-SEA FLUXES AND THE DISTRIBUTION OF SINK AND SOURCE OF CO_2 BETWEEN 80°W AND 80°E IN THE SOUTHERN OCEAN

The partial pressure of carbon dioxide in surface water and atmosphere along the track between Zhongshan Station and the Great Wall Station in the Southern Ocean was continually measured during the summer voyage for CHINARE XVI from December 1999 to February 2000. The results show that there is a sink for atmospheric CO 2 during summer between 80°W to 80°E in the Southern Ocean, especially in the area of 45°W to 30°W and 10°W to 10°E. The similar pattern of sink distribution can also be observed from the return observations from the Great Wall Station to Zhongshan Station. Absorbing CO 2 from air to sea in the investigated waters in January was twice higher than that in December. Using the newest calculation of transfer velocity of CO 2, fluxes of CO 2 was 3.98 and 2.13 mol/ (m 2·a) in January and December respectively. The average of total CO 2 fluxes in the Southern Ocean during summer was 3.06 mol/(m 2·a), suggesting an important summer sink of CO 2 in the South Hemisphere.