Black-Carbon

A holder for elemental carbon (EC) concentrations in the atmosphere. By default it does not include any dynamics — EC is treated as a conserved tracer whose concentration is set as an initial condition and carried forward unchanged. The model carries particle physical properties (density, diameter, temperature, pressure) so that coupled models (e.g. Mie scattering, mass transfer) can access them through the shared system. Particle density default from Fierce et al. (2023).