def ka_cont(T):
    """ Thermal conductivity of air, neglecting non-continuum effects.

    See :func:`ka` for details.

    Parameters
    ----------
    T :
        ambient air temperature surrounding droplet, K

    Returns
    -------
    float
        :math:`k_a(T)` in J/m/s/K

    See Also
    --------
    ka : includes correction for non-continuum effects.

    """
    return 0.001 * (4.39 + 0.071 * T)
