Aphids forward and backward migration simulations by SILAM CTM

The SILAM CTM (Chemical Transport Model) has been used to model the migration of bird cherry-oat aphids (Rhopalosiphum padi) across Europe. The forecasts are based on a temperature sum threshold (220 DD5), a source area map, and meteorological forecasts from the ERA5 weather model. The SILAM model’s emission term incorporates meteorological factors such as temperature, wind, and humidity to estimate aphid take off. Aphids are considered to behave like coarse airborne particles during their transport in the atmosphere.

Migration forecasts have been calculated for the years 2002, 2010, and 2016 (Jan 1 - Jul 31), and are provided as datasets (SILAM_Aphids2002.tar, SILAM_Aphids2010.tar, SILAM_Aphids2016.tar). Additionally, the source areas of the first aphids observed in Jokioinen, Finland, have been traced using an inverse modeling method for the years 2001–2016 (Jokioinen2001_2016_SILAMaphidInverse.tar) and same for Helsinki in 2002 (Helsinki2002_SILAMaphidsInverse.nc4). All model datasets are provided in NetCDF format.

SILAM CTM is developd at Finnish Meteorological Institue  and it is open open code http://silam.fmi.fi/ .