def dem_threshold(domain, b):

    heightLevel = float(domain.algorithm_params['dem_threshold'])
    dem         = domain.get_dem().image
    return dem.lt(heightLevel).select(['elevation'], ['b1'])


#==============================================================
Just use a height threshold on the DEM!
dataset/ETHPy150Open nasa/CrisisMappingToolkit/cmt/modis/simple_modis_algorithms.py/dem_threshold