Rain Gauge Data Quality Control and Combining Data from Different Networks for Hydrologic Applications
Abstract
Rainfall information is crucial for planning and managing water resource systems and for the monitoring and forecasting of hydrologic processes. Rainfall quantities measured by rain gauges on the ground are commonly used as true rainfall for the evaluation as well as the uncertaintity characterization of remotely-sensed rainfall estimates (e.g., radar and satellite estimates). In such applications, rain gauge data quality and density over a specific area of interest are the key factors affecting the reliabilty and significance of analysis results. Based on earlier studies, the main obstacle for the use of rain gauges as ground reference over large areas is the lack of quality rain gauges or of a standardized procedure to ensure the quality of the rainfall measurements when data from different networks are combined. The authors propose a framework to combine rainfall data from several rain gauge networks, maintained and operating for different purposes and for which rainfall information is recorded at different time scales, with some data quality control procedures. The proposed quality control method is applied to two years of rainfall data from four networks (ASOS, AWOS, SchoolNet, and a research network in Iowa City operated by the University of Iowa) in Iowa. This method addresses issues related to the sampling uncertainty in tipping bucket rain gauges and to the partial-missing data for the designated accumulation interval. The authors also perform a radar-gauge comparison using Stage IV radar-rainfall data, which are known to be unbiased estimates, and check rain gauge data for the consistency in temporal recording for the period. Spatial correlation among rain gauge locations is also analyzed to identify and exclude stations generating abnormally low or high correlations due to different uncertainty factors, such as device's malfunction. The results are presented for hourly rainfall accumulation data, even though it can also be used for longer or shorter accumulation times.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.H41I1278S
- Keywords:
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- 1840 HYDROLOGY / Hydrometeorology;
- 1853 HYDROLOGY / Precipitation-radar;
- 1854 HYDROLOGY / Precipitation