Within the scope of this work, a sensitivity analysis method for input parameters of numerical models is developed and applied to the PALM model system. For an application of PALM in urban areas, input data concerning land use, surfaces, soil type, buildings and vegetation are required. They can be obtained from various sources like municipal data, Open Street Map, satellite data or aerial imagery. However, quality and availability of input data are very heterogeneous, which results in uncertainties in the input parameters, which are transferred to the model results. In the presented study, the quality of the input parameters is investigated with respect to the required accuracy of the model results. A systematic sensitivity analysis based on the Morris method an a OAT sensitivity study is carried out for the input parameters required for PALM simulations of the urban environment. This allows for the selection of the input parameters, for which extensive data acquisition is worthwhile and necessary for obtaining reliable model results with a suffcient accuracy. In addition, conclusions are drawn on possible methods for the adaptation of urban areas to climate change based on the results of the sensitivity analysis discussing quantities with a large impact on theair temperature and the UTCI.