09:00 〜 10:30
[ACG37-P10] Analysis of biomass burning aerosol plumes using SGLI data
キーワード：GCOM-C/SGLI、バイオマス燃焼エアロゾル
The Japanese space mission JAXA/GCOM (Global Change Observation Mission-Climate)-C (SHIKISAI in Japanese), launched in 2017, was equipped with a second generation global imager (SGLI). We have been involved in the analysis of SGLI data for the past few years, taking advantage of the advanced measurement capabilities of the SGLI and focusing on optically very thick severe biomass burning aerosols (SBBA) events. This is because SBBA events provide a good opportunity to understand the boundary between clouds and aerosols, or the mixing band between the two. Furthermore, to understand and predict global climate change, it is essential to accurately understand the interactions between atmospheric particles and other factors. To do so, it is necessary to obtain more detailed information on aerosol absorption characteristics, particle size distribution, and vertical distribution. In this study, we use this multi-directional SGLI data to estimate the characteristics of the SBBA plume.
Severe wildfires occur around the world and are increasing in both frequency and intensity. It has become a major environmental problem. As a result, large amounts of biomass burning aerosols (BBA) are released into the atmosphere, causing air pollution and adversely affecting human health and social life. BBA generated by wildfires cause long-range advection. Such long-range advection depends mainly on meteorological fields, but it has been reported that in some regions of the world, heat-driven flows are a systematic feature of mountain meteorology and climate, which affect the flow of pollutants. Therefore, topographic influences and meteorological information are essential to understand the advection of BBA generated by forest fires. Biomass combustion is also a major source of trace gases and aerosols into the atmosphere. Because fires release large amounts of heat, the plumes they generate are buoyant and generate strong updrafts. This causes the plume to rise to considerable heights in the atmosphere. This complicates the vertical structure of biomass burning smoke. The vertical structure of biomass burning smoke is an important parameter for properly understanding and modeling atmospheric chemistry. It is also important for interpreting observations. In this study, we also attempt to derive vertical information on the biomass burning plume using satellite observation data. The objective of this study is to improve our understanding of BBA events by integrating space-based and ground-based observations and regional meteorological models.
SGLI has 19 channels ranging from near UV to thermal IR, including red (674 nm, PL1 band) and near IR (869 nm, PL2 band) polarization channels. The instantaneous field of view (IFOV) of the SGLI is as fine as 250 m in the near UV to short IR wavelength range and 1 km for polarimetric measurements. Note that this polarimetric measurement has the highest spatial resolution ever obtained on a global and multi-year scale. The polarization optics of SGLI makes oblique observation of ±45° (the switch between 45° and -45° is made above the equator), though the radiance optics takes straight down view. Therefore, radiance data of two directions can be obtained at every polarization observation pixel in SGLI, and multi-view polarization information can be obtained during the switching of the polarization optics in SGLI.
The structure of this study is as follows. First, the basic concept and retrieved results of BBA characteristics from SGLI data are presented, using the example of a large wildfire that occurred in western North America. Ground observations by NASA/AERONET are used to validate the results retrieved from the SGLI data as actual and, specific information about aerosols in the area of interest. Further, we show that SGLI’s simultaneous observation of radiance and polarization is useful for estimation of the vertical variation of aerosol properties. In order to reproduce the relevant meteorological field at a regional scale, the Scalable Computing for Advanced Library and Environment (SCALE)regional model is adopted in this study.
Severe wildfires occur around the world and are increasing in both frequency and intensity. It has become a major environmental problem. As a result, large amounts of biomass burning aerosols (BBA) are released into the atmosphere, causing air pollution and adversely affecting human health and social life. BBA generated by wildfires cause long-range advection. Such long-range advection depends mainly on meteorological fields, but it has been reported that in some regions of the world, heat-driven flows are a systematic feature of mountain meteorology and climate, which affect the flow of pollutants. Therefore, topographic influences and meteorological information are essential to understand the advection of BBA generated by forest fires. Biomass combustion is also a major source of trace gases and aerosols into the atmosphere. Because fires release large amounts of heat, the plumes they generate are buoyant and generate strong updrafts. This causes the plume to rise to considerable heights in the atmosphere. This complicates the vertical structure of biomass burning smoke. The vertical structure of biomass burning smoke is an important parameter for properly understanding and modeling atmospheric chemistry. It is also important for interpreting observations. In this study, we also attempt to derive vertical information on the biomass burning plume using satellite observation data. The objective of this study is to improve our understanding of BBA events by integrating space-based and ground-based observations and regional meteorological models.
SGLI has 19 channels ranging from near UV to thermal IR, including red (674 nm, PL1 band) and near IR (869 nm, PL2 band) polarization channels. The instantaneous field of view (IFOV) of the SGLI is as fine as 250 m in the near UV to short IR wavelength range and 1 km for polarimetric measurements. Note that this polarimetric measurement has the highest spatial resolution ever obtained on a global and multi-year scale. The polarization optics of SGLI makes oblique observation of ±45° (the switch between 45° and -45° is made above the equator), though the radiance optics takes straight down view. Therefore, radiance data of two directions can be obtained at every polarization observation pixel in SGLI, and multi-view polarization information can be obtained during the switching of the polarization optics in SGLI.
The structure of this study is as follows. First, the basic concept and retrieved results of BBA characteristics from SGLI data are presented, using the example of a large wildfire that occurred in western North America. Ground observations by NASA/AERONET are used to validate the results retrieved from the SGLI data as actual and, specific information about aerosols in the area of interest. Further, we show that SGLI’s simultaneous observation of radiance and polarization is useful for estimation of the vertical variation of aerosol properties. In order to reproduce the relevant meteorological field at a regional scale, the Scalable Computing for Advanced Library and Environment (SCALE)regional model is adopted in this study.