1:45 PM - 3:15 PM
[O08-P72] Relationship between atmospheric conditions and visibility
Keywords:visibility, weather condition, Suspended Particulate Matter (SPM), observation
Ⅰ. Introduction
I found an improvement of visibility after typhoon passed. Then, I wondered it was caused by weather conditions, after that, I started this study.
The purpose of this study is to reveal the requirements of its change and to forecasting the visibility.
Ⅱ. Methods
First, seeing fifteen target objects such as Yokohama Landmark Tower, Mt. Fuji, and Mt. Shiomi. Second, making judgements the visibility of that day by classifying whether those objects can be seen or not. Third, analyzing the factor of visibility’s change by comparing with its data and air pollutants or atmospheric data.
Observing has been done from July 15, 2022, to December 3, 2023. Analyzed data is from August 1, 2022, to July 31, 2023.
Ⅲ. Results
Firstly, analyzing about relationships between visibility and weather conditions. Consequently, relative humidity and absolute humidity are the most relevant atmospheric elements to changing visibility. However, those coefficients of determination are about 0.2, so other factors which affect stronger may be existed.
Then, I focused on Suspended Particulate Matters (SPM). As a result, there is very strong negative correlation(R≦-0.80) between concentration of SPM and visibility. Also, there is positive correlation(R=0.52) between concentration of SPM and relative humidity. Additionally, concentration of SPM is declined due to rain.
Furthermore, in the case of seeing further place, there are not only factor of SPM, but the weather condition at the place.
Ⅳ. Discussion and Conclusions
Mainly factor of visibility’s change is concentration of SPM, also, it is affected by humidity moreover weather conditions. Especially, raining affects to SPM’s declining. Even though it continues to fine, there are cases visibility improves by such a phenomenon. Meanwhile, further target objects, other factors such as the weather conditions nearby them affected visibility from observer. Thus, concentration of SPM is not necessarily related to visibility of all objects.
Also, now, it is difficult to forecast visibility.
Ⅴ. Prospects
I am going to analyze degree which individual of weather conditions or air pollutant affect to visibility’s change by regression analysis, and to forecast visibility.
Acknowledged
I would like to thank Mr. Suzuki and Ms. Shusse from NIED for useful advice in this study.
References
・Ministry of the Environment. Atmospheric Environmental Regional Observation System: Soramame-kun
・Ministry of the Environment. Mechanism of formation of SPM and oxidants [translated from Japanese]. Ministry of the Environment.
・Okada Masumi. J. Agr.Met. Computation of Air Humidity and Its Relevant Quantities. 1985, 40, 4, 407-409.
・Taguchi Komomo : Changes in visibility over 50 years and post-war air pollution at Tachikawa High School [translated from Japanese]. The Meteorological Society of Japan, 2019-05.
・Ueda Sayako. Miura Kazuhiko. Seasonal variation of hygroscopic properties of urban atmospheric aerosols at the center of Tokyo. J. Jpn.Soc. Atmos.Environ. 42(6), p.339~349 (2007).
・Website of Japan Meteorological Agency
・Website of Japan Weather Association
・Yasuhara Takumi. Visibility at Tachikawa High School [translated from Japanese]. The Meteorological Society of Japan, 2021-05.
I found an improvement of visibility after typhoon passed. Then, I wondered it was caused by weather conditions, after that, I started this study.
The purpose of this study is to reveal the requirements of its change and to forecasting the visibility.
Ⅱ. Methods
First, seeing fifteen target objects such as Yokohama Landmark Tower, Mt. Fuji, and Mt. Shiomi. Second, making judgements the visibility of that day by classifying whether those objects can be seen or not. Third, analyzing the factor of visibility’s change by comparing with its data and air pollutants or atmospheric data.
Observing has been done from July 15, 2022, to December 3, 2023. Analyzed data is from August 1, 2022, to July 31, 2023.
Ⅲ. Results
Firstly, analyzing about relationships between visibility and weather conditions. Consequently, relative humidity and absolute humidity are the most relevant atmospheric elements to changing visibility. However, those coefficients of determination are about 0.2, so other factors which affect stronger may be existed.
Then, I focused on Suspended Particulate Matters (SPM). As a result, there is very strong negative correlation(R≦-0.80) between concentration of SPM and visibility. Also, there is positive correlation(R=0.52) between concentration of SPM and relative humidity. Additionally, concentration of SPM is declined due to rain.
Furthermore, in the case of seeing further place, there are not only factor of SPM, but the weather condition at the place.
Ⅳ. Discussion and Conclusions
Mainly factor of visibility’s change is concentration of SPM, also, it is affected by humidity moreover weather conditions. Especially, raining affects to SPM’s declining. Even though it continues to fine, there are cases visibility improves by such a phenomenon. Meanwhile, further target objects, other factors such as the weather conditions nearby them affected visibility from observer. Thus, concentration of SPM is not necessarily related to visibility of all objects.
Also, now, it is difficult to forecast visibility.
Ⅴ. Prospects
I am going to analyze degree which individual of weather conditions or air pollutant affect to visibility’s change by regression analysis, and to forecast visibility.
Acknowledged
I would like to thank Mr. Suzuki and Ms. Shusse from NIED for useful advice in this study.
References
・Ministry of the Environment. Atmospheric Environmental Regional Observation System: Soramame-kun
・Ministry of the Environment. Mechanism of formation of SPM and oxidants [translated from Japanese]. Ministry of the Environment.
・Okada Masumi. J. Agr.Met. Computation of Air Humidity and Its Relevant Quantities. 1985, 40, 4, 407-409.
・Taguchi Komomo : Changes in visibility over 50 years and post-war air pollution at Tachikawa High School [translated from Japanese]. The Meteorological Society of Japan, 2019-05.
・Ueda Sayako. Miura Kazuhiko. Seasonal variation of hygroscopic properties of urban atmospheric aerosols at the center of Tokyo. J. Jpn.Soc. Atmos.Environ. 42(6), p.339~349 (2007).
・Website of Japan Meteorological Agency
・Website of Japan Weather Association
・Yasuhara Takumi. Visibility at Tachikawa High School [translated from Japanese]. The Meteorological Society of Japan, 2021-05.