AER_FRATE (L4)
Description
Aerosol Mass Flow Rate (AER_FRATE) is a quantitative estimate of an hourly amount of aerosol movement based on the aerosol optical depth (AOD) observed by GEMS. AER_FRATE is calculated using wind information after removing the AOD background concentration of each grid (spatial resolution: 0.2° x 0.2°).
While AOD shows distribution of aerosol concentration at the relevant time, AER_FRATE provides more details on the amount and route of aerosols transported from other regions. Moreover, comparison between AOD and AER_FRATE for the same time slot enables to predict whether aerosols would move from Korea to surrounding areas by atmospheric diffusion, or accumulate where they currently are.
Orientation of the arrow indicates wind direction, that is the direction of aerosol transport, and the length and color of the arrow contain information on the amount of movement. A long red arrow means a large amount of aerosol movement whereas a short blue arrow implies that aerosols flow in a small volume.
Applications
When the concentration of particulate matter (PM) is higher than usual, AER_FRATE can be applied to analyze the distribution and movement of PM over the Asian region and the Korean Peninsula in more detail. This can help figure out the cause of high concentration and the atmospheric conditions.
AER_FRLATE tends be sensitive to errors in AOD, aerosol type, and vertical distribution of aerosols used as input data. In addition, wind information that contains results of the weather forecast model UM is averaged in the altitude range of 0 - 5.6 km (1,000 - 500 hPa), which may result in discrepancies from the actual wind direction and speed.