13 landuse categories are related roughness length
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landuse   comment                               z0
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 1 Urban land                                   0.7
 2 Agricultural land                            0.1
 3 Range land                                   0.1
 4 Deciduous forest                             1.
 5 Coniferous forest                            1.
 6 Mixed forest including wetland               0.7
 7 water, both salt and fresh                   0.001
 8 barren land mostly desert                    0.01
 9 nonforested wetland                          0.1
10 mixed agricultural and range land            0.1
11 rocky open areas with low grow shrubs        0.05
12 snow and ice                                 0.001
13 rainforest                                   1.
