基于浮标观测的春季青岛近岸海水pCO_(2)变化及海-气CO_(2)通量研究

Variations of pCO_(2)and sea-air CO_(2)flux in Qingdao coastal seawater in spring based on buoy observations

利用海-气界面浮标观测得到的高频数据,分析了春季青岛近岸海域海表二氧化碳分压(pCO_(2))的变化规律及驱动因素,并对海-气CO_(2)通量进行了估算。观测期间该海域由大气的碳汇转变为碳源,主要是由海表pCO_(2)的不断增长所致。对海表pCO_(2)控制因素进行分析,发现温度升高是pCO_(2)增长的主要驱动因素,生物过程起到一定的抑制作用。海表pCO_(2)呈现出日变化特征,温度和生物因素对海表pCO_(2)日变化的作用均与太阳辐射相关,但两者的作用相反。此外,分析发现浮标的不同采样频率会对海-气CO_(2)通量估算产生影响,缩短采样间隔能有效降低海-气CO_(2)通量估算的偏差,提高估算的准确性。

Based on the high frequency data of sea-air interface buoys,the variation pattern and driving factors of sea-air partial pressure of carbon dioxide(pCO_(2))were analyzed and the sea-air CO_(2)flux in the coastal waters of Qingdao in spring was estimated.During the observation period,the sea area changed from a carbon sink of atmospheric CO_(2)to a carbon source,which was mainly caused by the continuous increase of sea surface pCO_(2).By analyzing the controlling factors of pCO_(2),it was found that temperature was the main driving factor of pCO_(2)growth,and biological processes played a certain inhibiting role.The sea surface pCO_(2)showed a diurnal variation.The effects of temperature and biological factors on the diurnal variation of p CO_(2)were related to solar radiation,but they had opposite effects.In addition,the analysis showed that different sampling frequencies of buoys affected the estimation of sea-air CO_(2)flux and shortening the sampling interval could effectively reduce the deviation of CO_(2)flux estimation and improve the accuracy of estimation.