Analysis of the Characteristics of Each Other's Acid Rain (Snow) and Aerosol Samples.

1995年4月至1997年1月在山形县鹤冈市收集了降水和气溶胶样品，并分析了化学成分。我们想在调查和获得的资料上探讨日本海沿岸酸雨和雪的特征以及降水和大气微粒沉积（气溶胶）中酸化物质的来源。经过审议，提出了下列事项：(1)降水和气溶胶中海盐源离子（Na^+、Cl^-、Mg^<2+>、Ca^<2+>和K^+）浓度在冬季至春季高于夏季，这是由于每年11月至6月亚洲大陆季风和季节性风的爆发强烈所致。(2)土壤源元素（Al、Fe和nss-Ca^<2+>）浓度与含黄土和沙土的西风强度成正比，导致春季出现Kosa现象。(3)降雨和降雪的酸化机制可能由[nss-SO_4^<2->]和[NO_3^-]等酸化组分与[NH_4^+]和[nss-Ca^<2+>]等中性组分的浓度比决定。(4)非海盐硫酸盐离子[nss-SO_4^2]在鹤冈气溶胶样品中含量最多，全年测得的高值（4.6 μ g/m^3）是西川、内陆地区、山形县的两倍以上，且在风向为西吹时[nss-SO_4^2]的含量高于风向为东吹时的含量。(5)降水和气溶胶中微量金属的浓度也受风向的影响，大气中的Pb和Zn可以通过大陆城市的西风输送，Sr与亚洲大陆的沙漠土壤密切相关。(6)鹤冈的降雨和降雪均为酸雨和酸雪，占90%以上，气溶胶均为酸性大气沉降。

Precipitation and aerosol samples were collected from April. 1995 to January. 1997 in Tsuruoka, Yamagata prefecture and anlyzed for chemical components.We should like to probe for the characteristics of acid rain and snow at the coast of the Japan Sea and the origin of acidified matters in precipitaion and particulate atmospheric deposition (aerosols) on the investigated and obtained data.As the result of considering, the following were mentioned ;(1) The concentrationof the sea salt source ions (Na^+, Cl^-, Mg^<2+>, Ca^<2+>, and K^+) in precipitation and aerosol were higher value from winter to spring, than summer season for the reason that outburst of monsoon and seasonal wind from Asian continent had been strong from November to June, yearly.(2) About soil source elements (Al, Fe and nss-Ca^<2+>), the concentration were higher in proportion to the strength of the west-wind with containing of loess and desert sand, caused Kosa phenomenon in spring.(3) The acidifing mechanism of rainfall and snowfall might have been decided by the concentration ratio of acidified component such as [nss-SO_4^<2->] and [NO_3^-] to neutral component such as [NH_4^+] and [nss-Ca^<2+>].(4) Non-sea-salt sulfate ion [nss-SO_4^2] in Tsuruoka were contained most large amount in aerosol samples and the concentraton measured at high value (4.6mug/m^3) throughout the year were more than twice as much as in Nishikawa, inland areas, Yamagata prefecture, and further, [nss-SO_4^2] becamed higher value when the sind had been blowing from the west than the east.(5) The concentration of trace metals in precipitation and aerosol also were influenced by the wind directions, for instance, atmospheric Pb and Zn could be transported by the west-wind from continental cities and Sr were closely connected to desert soil from the Asian continent.(6) Rainfall and Snowfall in Tsuruoka wre acid rain and acid snow at the rate of more than ninety percent and aerosols were all acid atmospheric deposition.