Characteristics of temporal and spatial evolution of rainfall under the
influence of urbanization---A case study of the Beijing-Tianjin-Hebei
region
Abstract
Based on the rainfall data from 197 rain gauge stations for the period
1960 to 2019, linear regression, moving average, and SURFER spatial
analysis were used to analyze the temporal and spatial characteristics
of rainfall in the Beijing-Tianjin-Hebei region, and compare the
difference in rainfall between the mountainous areas and plains, during
the flood season. The results show that (1) the overall duration of
rainfall in each region of Beijing-Tianjin-Hebei exhibit a downward
trend, and the overall spatial performance gradually decreases from east
to west. (2) The mountainous areas in the Beijing-Tianjin-Hebei region
are prone to light and moderate rainfall events; the plains are more
prone to rainfall events at levels above moderate rain, especially
rainstorms and heavy rain events; the probability of light and moderate
rainfall events in the suburbs is close to that of the urban areas, but
the probability of rainfall events at levels above heavy rain is less
than that of the urban areas; the probability of rainfall events of all
levels in the outer suburbs is higher. (3) Increase in rainfall in urban
areas compared to the southern suburbs is greater than when compared
with the northern suburbs which are at different stages of urbanization,
but the effect of urbanization on rainfall is also reflected in the
comparison between the urban areas and the northern suburbs. (4) With
increasing urbanization, the built environment in the mountainous areas
and plains of the Beijing-Tianjin-Hebei region has continued to grow,
and the original underlying surface conditions have changed. Because the
urbanization process is faster in the urban areas than in the suburbs,
the changes to the underlying surface conditions lead to greater
increase in rainfall in urban areas during the flood season compared to
the suburbs; the urban areas are also more prone to rainfall events at
levels above heav