Influence on simulation accuracy of atmospheric electric field around a building by space resolution

The actual value of the atmospheric electric field intensification upon the top of a building in continuous space is important for the atmospheric electricity researches but hardly obtained through observations and numerical computations. An extrapolation method has been adopted for estimating the actual value from a fitted formula. This estimated actual value was defined as the extrapolated value, and the relationship between the extrapolated value and the building dimension is obtained. By comparing the calculated value in a certain resolution with the extrapolated value, the systematic error of the calculated value has been found to be a fixed value, which is closely associated with the resolution rather than a structure's dimension. The extrapolated value has a more significant correlation with the smallest mesh spacing of the point chosen for the fitted formula, but less with the number and distribution of the points.