Abstract
Traditional deterministic and geostatistical methods for rainfall
interpolation usually fall short of integration of data on a variety of
variables. These omitted variables include seasonal variables such as
time of year, topographic variables such as elevation, and/or remote
sensing variables such as radar reflectivity. Meanwhile, poor quality in
data on certain variables for some data points poses challenges to
modelers who are using machine learning approaches to estimate rainfall
amounts for locations without gauge measurements. To overcome these
limitations, this presentation introduces a novel deep learning-based
approach to recreate rainfall histories for large geographic areas with
a high spatio-temporal resolution. The proposed approach enables
integration of data on a variety of variables by adopting a multi-layer
perceptron modeling framework. The introduction of binary variables on
data quality as additional input variables resolves the issue of unequal
data quality for different data points. As a demonstration, historical
records of rainfall at hourly and daily intervals recorded at 139 rain
gauge stations in or close to Harris County, Texas, from 1986 to 2013
are used, along with other auxiliary variables, to train deep learning
regression models to interpolate rainfall at surface level. Results of
validation and recreated spatiotemporal distributions of rainfall
indicate good performance of the proposed approach compared to both
gauged and radar data. The final product of the proposed approach can be
applied to other regions, with information on hindcast historical
rainfall events, for pluvial flood risk analysis. The approach will
assist researchers and policy specialists to validate hydrologic
modeling as well as for training machine learning models to identify
extreme rainfall events to facilitate early warning and emergency
response.