Calculation

Calculation

This tool calculates two types of footprints at any date and location. One is the contribution of near surface particles arriving at a given point, and the other is the distribution of particles emitted from a given point.

Figure 1 shows the results of the contribution of the near surface particles at Hateruma station. The color contour indicates the mean residence time of Lagrangian particles in 1°×1° grid cells in the upwind regions to the observation point.

Movie 1 shows every 3-hours distributions of particles emitted from the coast of Fukushima Prefecture and dispersed for 10 days.

example of footprint: backward
Figure 1 Contribution of the near surface particles at Hateruma station. The color contour shows the particle residence time RT[s] in log10(1+RT).
example of footprint: forward
Movie 1 Distribution of particles emitted from the coast of Fukushima Prefecture on March 11, 2011. The color contour shows the particle residence time RT[s] in log10(1+RT).

This tool uses FLEXCPP (Zeng, et al., 2013 ) which is a Lagrangian particle dispersion program developed by the Center for Global Environmental Research (CGER), Earth System Division (ESD), National Institute for Environmental Studies (NIES) based on the open source FLEXPART (FLEXible PARTicle dispersion model).

This tool is provided not only by online but also by packages to calculate on the local machine. If you are interested, please contact us below.

Archives

Archives

The archives provide calculated footprints of the 10-day backward trajectory when 10,000 Lagrangian particles are released from Hateruma and Cape Ochiishi stations. The footprints after 1990 are available.

Contact

For inquiries about this site or analysis, please contact us.