parcel_model.activation.lognormal_activation

parcel_model.activation.lognormal_activation(smax, mu, sigma, N, kappa, sgi=None, T=None, approx=True)

Compute the activated number/fraction from a lognormal mode

Parameters:

smax : float

Maximum parcel supersaturation

mu, sigma, N : floats

Lognormal mode parameters; mu should be in meters

kappa : float

Hygroscopicity of material in aerosol mode

sgi :float, optional

Modal critical supersaturation; if not provided, this method will go ahead and compute them, but a temperature T must also be passed

T : float, optional

Parcel temperature; only necessary if no sgi was passed

approx : boolean, optional (default=False)

If computing modal critical supersaturations, use the approximated Kohler theory

Returns:

N_act, act_frac : floats

Activated number concentration and fraction for the given mode