def get_var_names(variable):
    """
    get the long variable names from 'flow' or 'temp'
    :param variable: [str] either 'flow' or 'temp'
    :return: [str] long variable names
    """
    if variable == "flow":
        obs_var = "discharge_cms"
        seg_var = "seg_outflow"
    elif variable == "temp":
        obs_var = "temp_c"
        seg_var = "seg_tave_water"
    else:
        raise ValueError('variable param must be "flow" or "temp"')
    return obs_var, seg_var