def calculate_phases_co2_emissions(cumulative_co2_emissions, phases_distances):
    """
    Calculates the CO2 emission of cycle phases [CO2g/km].

    :param cumulative_co2_emissions:
        Cumulative CO2 of cycle phases [CO2g].
    :type cumulative_co2_emissions: numpy.array

    :param phases_distances:
        Cycle phases distances [km].
    :type phases_distances: numpy.array

    :return:
        CO2 emission of cycle phases [CO2g/km].
    :rtype: numpy.array
    """
    return cumulative_co2_emissions / phases_distances
