This digital document is a journal article from Atmospheric Environment, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any ...
Description:
We undertook continuous measurements of SO"2 concentrations at the summit of Mt. Fuji, Japan (3776m above sea level), during the period January to July, 2004. These data include the first data set that fills the previous gap in SO"2 time series for the springtime middle troposphere over Japan. The time series shows trends in high-SO"2 long-range transport events from winter to spring. Elevated SO"2 concentrations are always accompanied by elevated CO and ^2^2^2Rn concentrations, and backward trajectories for such events indicate a continental origin. These data display clear sporadic signatures of Asian outflow over Japan to the North Pacific. Such high-SO"2 events decline in strength and frequency during spring. The observed seasonal variation of SO"2 events may in fact have nothing to do with seasonality in SO"2 emissions from the Asian continent, as seasonal patterns in SO"2 events show a similar phase shift to that of the prevailing wind direction and relative humidity (RH) observed on-site. The changes in air mass indicated by daily backward trajectory analysis may also explain the observed temporal changes in SO"2 events. A major factor appears to be the removal of SO"2 from the continental pollution plume during long-range transport. The SO"2-bearing polluted air is dry during the depths of winter; accordingly, little SO"2 is removed by cloud processes at this time of year. The nature of the air mass changes during spring when increasing humidity levels lead to the increased removal of SO"2 by cloud processes. RH data along the air mass travel path also support the importance of cloud processes in reducing SO"2 concentrations within the pollution plume.
 |  Format : HTML Author : Y. Igarashi Number of Pages : 15 Publisher : Elsevier List Price: Our Price: $10.95 |
Product Description
This digital document is a journal article from Atmospheric Environment, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.Description:
We undertook continuous measurements of SO"2 concentrations at the summit of Mt. Fuji, Japan (3776m above sea level), during the period January to July, 2004. These data include the first data set that fills the previous gap in SO"2 time series for the springtime middle troposphere over Japan. The time series shows trends in high-SO"2 long-range transport events from winter to spring. Elevated SO"2 concentrations are always accompanied by elevated CO and ^2^2^2Rn concentrations, and backward trajectories for such events indicate a continental origin. These data display clear sporadic signatures of Asian outflow over Japan to the North Pacific. Such high-SO"2 events decline in strength and frequency during spring. The observed seasonal variation of SO"2 events may in fact have nothing to do with seasonality in SO"2 emissions from the Asian continent, as seasonal patterns in SO"2 events show a similar phase shift to that of the prevailing wind direction and relative humidity (RH) observed on-site. The changes in air mass indicated by daily backward trajectory analysis may also explain the observed temporal changes in SO"2 events. A major factor appears to be the removal of SO"2 from the continental pollution plume during long-range transport. The SO"2-bearing polluted air is dry during the depths of winter; accordingly, little SO"2 is removed by cloud processes at this time of year. The nature of the air mass changes during spring when increasing humidity levels lead to the increased removal of SO"2 by cloud processes. RH data along the air mass travel path also support the importance of cloud processes in reducing SO"2 concentrations within the pollution plume.