stilt.particles.ParticlesAccessor.enhancement

ParticlesAccessor.enhancement(flux)

Return each particle’s enhancement, foot times flux summed along its trajectory.

The mean over particles, after any weighting, is the modeled enhancement at the receptor. Unlike foot.stilt.enhancement, the flux is taken at each particle position, with no gridding or smoothing.

Parameters:

flux (DataArray) – Surface flux on a lat/lon grid, in µmol m⁻² s⁻¹ for an enhancement in ppm. A flux with a time dimension is read as steps that start at their labels, as foot.stilt.enhancement reads it: each particle row takes the last flux step that starts at or before the row’s time. A row before the first label gets zero flux, and a row after the last label takes the last step. A flux labeled at the middle of its steps must be relabeled first (see foot.stilt.enhancement). Points outside the flux grid, and missing cells, count as zero flux.

Returns:

Enhancement indexed by particle. A particle that never crosses the flux field gets 0.

Return type:

Series

Raises:

ValueError – If the flux varies in time and the particles have no time column.