沙尘和灰霾期间中国近海大气氮沉降通量估算

利用WRF-CMAQ模型估算了2011年4月26日~5月3日沙尘事件和2016年1月1日~7日灰霾事件在中国近海引起的总无机氮（TIN）沉降通量，分析了两类事件对中国近海海洋初级生产力的贡献，探究了灰霾事件时中国近海无机氮沉降的可能来源.结果表明：典型沙尘和灰霾过程中，中国近海TIN干沉降通量均值分别为6.77，3.01mg N/（m²·d），是晴朗天的6.84，3.04倍，可提供38.5，17.1mg C/（m²·d）的海洋初级生产力；沙尘期间无机氮沉降以还原态氮（NH₃和铵态氮，占TIN的62.2%）为主，灰霾期间则以氧化态氮（HNO₃和硝态氮，占TIN的84.3%）为主.典型沙尘事件TIN沉降对黄海影响最大，对渤海影响最小；典型灰霾事件对黄海和东海TIN沉降影响相当，高于对渤海的贡献.典型灰霾期间，京津冀和山东西北部（区域一）对渤、黄、东海TIN干沉降的贡献均大于长江三角洲及周边地区（区域二），区域一对3个海域TIN干沉降的贡献约为38.7%~74.6%，区域二的贡献约为1.14%~12.1%.

Atmospheric nitrogen deposition fluxes during dust and haze events over China Seas

The dry deposition fluxes of total inorganic nitrogen (TIN) to the China Seas during one dust (April 26~May 3, 2011) and one haze event (January 1~7, 2016) were calculated by WRF-CMAQ model. Contributions of the TIN deposition to the marine primary productivity during two events were also analyzed. Two inland polluted regions were selected to explore their contributions to the deposition of TIN over China Seas during the haze event. The results showed that TIN dry deposition flux over China Seas were 6.77 and 3.01mg N/(m²·d) during the dust and haze event respectively, which were about 6.84 and 3.04 times higher than that of the nonevent days. The nitrogen deposition during two events can be converted to new primary biological productivities of 38.5 and 17.1mg C/(m²·d) over China Seas, respectively. Reduced nitrogen (NH₃ and NH₄⁺, accounting for 62.2% of TIN dry deposition flux) was the main component of TIN deposition during dust event while the oxidized nitrogen (HNO₃ and NO₃^-, accounting for 84.3% of TIN dry deposition flux) was main components during the haze event. Highest deposition fluxes during dust event was found in Yellow Sea while the lowest fluxes was in Bohai Sea. During the haze days, dry deposition of TIN over Yellow Sea and East China Sea were roughly the same, which were higher than that in Bohai Sea. During this haze event, TIN deposition over the Bohai Sea, Yellow Sea and East China Sea from Beijing-Tianjin-Hebei & Northwest of Shandong (Region 1) were higher than that from Yangtze River Delta (Region 2). The contribution to TIN dry deposition flux over China adjacent seas from Region 1was in the range of 38.7%~74.6% and about 1.14%~12.1% from Region 2.