Acidic and related constituents in liquid water stratiform clouds
Acidic and related constituents in liquid water stratiform clouds
复制标题
液态水层状云中的酸性和相关成分
DOI：
10.1029/jd089id01p01447
复制
发表时间：
1984
影响因子：
--
通讯作者：
L. Newman
中科院分区：
文献类型：
--
作者：
P. Daum;S. Schwartz;L. Newman
1982年2月在南卡罗来纳州查尔斯顿附近的飞机测量报告了云液态水和间隙空气的组成。云水是用一种开槽棒式撞击器收集的。通过离心分离器获得无云间隙空气。云水中的离子种类主要为H/sup +/、SO/sub - 4//sup -/、NO/sub - 3//sup -/和NH/sub - 4//sup +/。以H/sup +/与NH/ sup +/ //sup +/之比测定，云水的相对酸度远远大于间隙气溶胶或晴空气溶胶样品。云内间隙空气中存在气态O/sub - 3/、NO/sub - 3/（即NO+NO/sub - 2/）和SO/sub - 2/，而HNO/sub - 3/和NH/sub - 3/低于检测限（两种物质均为0.4 ppb）。将云水样品的相对酸度与晴空样品的相对酸度进行比较，表明晴空气溶胶和HNO/sub - 3/不能提供在云水中观测到的酸度水平。这种酸度与云内SO/sub - 2/或SO/sub - 2/+NO/sub - 4/的普遍浓度转化为水溶液强酸是一致的，尽管不能排除其他假设。将云水成分的绝对浓度与晴空测量的浓度进行比较，没有显示出云对硫和更多氮物质的积累。«少
Composition of cloud liquid water and interstitial air is reported for aircraft measurements near Charleston, South Carolina, in February 1982. Cloud water was collected by means of a slotted-rod impactor. Cloud-free interstitial air was obtained by a centrifugal separator. Principal ionic species in cloudwater were H/sup +/, SO/sub 4//sup -/, NO/sub 3//sup -/, and NH/sub 4//sup +/. The relative acidity of cloudwater, as measured by the ratio of H/sup +/ to NH/sub 4//sup +/, was much greater than that of the interstitial aerosol or of clear-air aerosol samples. Gaseous O/sub 3/, NO/sub 3/ (i.e., NO+NO/sub 2/), and SO/sub 2/ were present in interstitial air within clouds, whereas HNO/sub 3/ an NH/sub 3/ were below limit of detection (0.4 ppb for both species). Comparision of relative acidity of cloudwater samples with that of clear-air samples suggests that clear-air aerosol and HNO/sub 3/ are incapable of providing the levels of acidity observed in cloudwater. Such acidity would be consistent with in-cloud conversion of prevailing concentrations of SO/sub 2/ or SO/sub 2/+NO/sub 4/ to aqueous strong acid, although other hypotheses cannot be excluded. Comparison of absolute concentrations of cloudwater constituents to concentration in clear-air measurements gives no indication of accumulation of sulfur andmore » nitrogen species by clouds.« less