I want to transform local emissions to CMAQ grid cell (COLS ROWS), for example, i input the lat and lon information and it can automatically calculate the lat lon information belongs to which model grid cell(COLS ROWS), and put emissions to this gird cell. for example i input the (38.993,117.319), it can calculate the model gridcell (13,39) ? Thank you!
it may be like this in m3tools
call latlon2colrow(lat,lon,projection,cols,rows),but i can’t find it, thank you!
Since presumably the lat-lon grid is coarser than the CMAQ grid, you want to use interpolation instead of area-weighted transformation matrices. so the appropriate program is m3cple – see https://cjcoats.github.io/ioapi/M3CPLE.html.
On the other hand, you’ll need to take care of the units-rescaling: CMAQ emissions traditionally are not in interpolatable MKS units, but rather in “mass per grid cell” units, and you will probably need some rescaling dependent upon the units of the input data and the grid-cell areas of the CMAQ output grid. m3combo can be used for that re-scaling.
Thank you. professors.