報告書番号

285012

タイトル（和文）

大気拡散場における気象要素の代表性（2）（風の観測値を持つ地域代表性と季節代表性）

タイトル（英文）

THE REPRESENTATIVENESS OF WIND FIELD

概要 （図表や脚注は「報告書全文」に掲載しております）

環境アセスメント・モニタリングの高度化，合理化の観点に立ち，観測地点の地域代表性を明らかにすることを目的とし，前報で提示した新手法，すなわち多変量解析法を用いた一連の方法（主成分分析法とクラスター分析法の結合法）を，大気汚染物質の環境濃度と特に係りが深い風の場に適用し，手法の妥当性および得られた結果について検討した。この結果，各観測点の持つ空間代表性が明瞭に示され，本手法の適用の妥当性が明らかにされた。本結果中，特に海岸部において，周辺地域と異なった特性を持つ地域がいくつか見られた。この場合の風速の観測値は，その周囲の代表値として用いるのには適していないことが示唆された。本手法の応用手法が，環境アセスメントのために行われる気象観測の季節代表性に対する評価法として利

概要 （英文）

FOR THE RATIONAL ASSESSMENT OR MONITORING OFAIR QUALITY, IT IS REQUIRED TO EXAMINE THE REPRESENTATIVENESS OF METEOROLOGICAL OR POLLUTANT DATA, OR IN OTHER WORD TO EXAMINE THE LOCATION OF METEOROLOGICAL OR MONITORING STATIONS. IN THIS PAPER, A NEW METHOD PROPOSED BY KATO AND NISHINOMIYA(1984) IS APPLIED TO MAKE CLEAR THE REGIONALITY OF THE WIND FIELD WHICH CONTROLS THE DIFFUSION OR ADVECTION OF POLLUTANT, AND IS EXAMINED WITH RESPECT TO ITS PROPRIETY FOR THIS CASE. THERE ARE FIVE STEPS IN THE METHOD FOR THIS CASE. THE FIRST STEP IS TO EXTRACT SOME DOMINANT DISTRIBUTION PATTERN (PHENOMENA) OF DAILY VARIABILITY FOR THE WINDSPEED USING PCA (PRINCIPAL COMPONENT ANALYSIS). IN THESECOND STEP, THE FACTOR LOADINGS, WHICH SHOW THE CONNECTION AND INTERACTION BETWEEN SUCH PHENOMENON AND WIND SPEED FROM EACH STATION, ARE CALCULATED FOR EACH STATION. IN THE THIRD STEP, CORRESPONDING METEOROLOGICAL PHENOMENA WHICH CAUSE EACH PATTERN ARE INVESTIGATED. IN THE FORTH STEP, THE METEOROLOGICAL UNIFORM AREAS ARE CLARIFIED BY MEANS OF CLUSTER ANALYSIS FROM FACTOR LOADINGS. IN THE LAST STEP, THE DAILY WIND DISTRIBUTION PATTERNS WERE CLASSIFIED INTO SOME TYPES BY THE CLUSTER ANALYSIS USING DAILY PRINCIPAL COMPONENT CALCULATED AT EACH DAY, AND THE SEASONAL VARIATION OF EACH TYPES ARE INVESTIGATED. THIS METHOD IS APPLIED TO THE AMEDAS TEMPERATURE DATA OVER THE TOHOKU DISTRICT IN 1979 IN ORDER TOCOMPARE THE PREVIOUS RESULT.THE REGIONALITY OF THE WIND FIELD IS SHOWNCLEARLY, AND THE RESULT INDICATES THAT THIS METHOD IS USEFUL FOR SUCH ANALYSES. IT IS POINTED OUT THAT SOME METEOROLOGICAL STATION, ESPECIALLY IN THE COASTAL REGION, SHOULD NOT BE USED IN THE METEOROLOGICAL ANALYSIS EXCEPT FOR THE LOCAL PHENOMENA. IN THE SERIES OF ANALYSES, AN APPLIED METHOD IS PROPOSED AND USED FOR THE INVESTIGATION OF THE TEMPORAL REPRESENTATIVENESS OF THE DATA.

報告者

キーワード