Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China
Precipitation is a major component of the water cycle. Accurate and reliable estimation of precipitation is essential for various applications. Generally, there are three main types of precipitation products: satellite based, reanalysis, and ground measurements from rain gauge stations. Each type ha...
| Main Authors: | , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-08-01
|
| Series: | Remote Sensing |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2072-4292/15/17/4230 |
| _version_ | 1797581932639289344 |
|---|---|
| author | Yongming Shi Cheng Chen Jun Chen Babak Mohammadi Majid Cheraghalizadeh Mohammed Abdallah Okan Mert Katipoğlu Haotian Li Zheng Duan |
| author_facet | Yongming Shi Cheng Chen Jun Chen Babak Mohammadi Majid Cheraghalizadeh Mohammed Abdallah Okan Mert Katipoğlu Haotian Li Zheng Duan |
| author_sort | Yongming Shi |
| collection | DOAJ |
| description | Precipitation is a major component of the water cycle. Accurate and reliable estimation of precipitation is essential for various applications. Generally, there are three main types of precipitation products: satellite based, reanalysis, and ground measurements from rain gauge stations. Each type has its advantages and disadvantages. Recent efforts have been made to develop various merging methods to improve precipitation estimates by combining multiple precipitation products. This study evaluated for the first time the performance of the random forest-based merging procedure (RF-MEP) method in enhancing the accuracy of daily precipitation estimates in Chongqing city, China with a complex terrain and sparse observational data. The RF-MEP method was used to merge three widely used gridded precipitation products (CHIRPS, ERA5-Land, and GPM IMERG) with ground measurements from a limited number of rain gauge stations to produce the merged precipitation dataset. Eight stations (approximately 70% of the available stations) were used to train the RF-MEP approach, while four stations (30%) were used for independent testing. Various statistical metrics were employed to assess the performance of the merged precipitation dataset and the three existing precipitation products against the ground measurements. Our results demonstrated that the RF-MEP approach significantly enhances the accuracy of daily precipitation estimates, surpassing the performance of the individual precipitation products and two other merging methods (the simple linear regression model and the simple averaging). Among the three existing products, ERA5-Land exhibited the best performance in capturing daily precipitation, followed by GPM IMERG, while CHIRPS performed the worst. Regarding precipitation intensity, all three existing products and the RF-MEP merged dataset performed well in capturing light precipitation events with an intensity of less than 1 mm/day, which accounts for the majority (more than 70%) of occurrences. However, all datasets showed rather poor capability in capturing precipitation events beyond 1 mm/day, with the worst performance observed for extreme heavy precipitation events exceeding 50 mm/day. The RF-MEP approach significantly improves the detection ability for all precipitation intensities, except for the most extreme intensity (>50 mm/day), where only marginal improvement is observed. Analysis of the spatial pattern of precipitation estimates and the temporal bias of daily precipitation estimates further confirms the superior performance of the RF-MEP merged precipitation dataset over the three existing products. |
| first_indexed | 2024-03-10T23:14:39Z |
| format | Article |
| id | doaj.art-b36d30b9803e4f9cbc4d4df32e3c15e1 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-10T23:14:39Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-b36d30b9803e4f9cbc4d4df32e3c15e12023-11-19T08:46:15ZengMDPI AGRemote Sensing2072-42922023-08-011517423010.3390/rs15174230Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, ChinaYongming Shi0Cheng Chen1Jun Chen2Babak Mohammadi3Majid Cheraghalizadeh4Mohammed Abdallah5Okan Mert Katipoğlu6Haotian Li7Zheng Duan8School of Public Administration, Chongqing Technology and Business University, Chongqing 400067, ChinaCenter for Eco-Environmental Research, Nanjing Hydraulic Research Institute, Nanjing 210029, ChinaSchool of Environment and Energy Engineering, Anhui Jianzhu University, Hefei 203601, ChinaDepartment of Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, SE-223 62 Lund, SwedenDepartment of Irrigation and Reclamation Engineering, University of Tehran, Karaj 31587-77871, IranCollege of Hydrology and Water Resources, Hohai University, Nanjing 210024, ChinaDepartment of Civil Engineering, Erzincan Binali Yıldırım University, 24002 Erzincan, TurkeySchool of Environment and Energy Engineering, Anhui Jianzhu University, Hefei 203601, ChinaDepartment of Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, SE-223 62 Lund, SwedenPrecipitation is a major component of the water cycle. Accurate and reliable estimation of precipitation is essential for various applications. Generally, there are three main types of precipitation products: satellite based, reanalysis, and ground measurements from rain gauge stations. Each type has its advantages and disadvantages. Recent efforts have been made to develop various merging methods to improve precipitation estimates by combining multiple precipitation products. This study evaluated for the first time the performance of the random forest-based merging procedure (RF-MEP) method in enhancing the accuracy of daily precipitation estimates in Chongqing city, China with a complex terrain and sparse observational data. The RF-MEP method was used to merge three widely used gridded precipitation products (CHIRPS, ERA5-Land, and GPM IMERG) with ground measurements from a limited number of rain gauge stations to produce the merged precipitation dataset. Eight stations (approximately 70% of the available stations) were used to train the RF-MEP approach, while four stations (30%) were used for independent testing. Various statistical metrics were employed to assess the performance of the merged precipitation dataset and the three existing precipitation products against the ground measurements. Our results demonstrated that the RF-MEP approach significantly enhances the accuracy of daily precipitation estimates, surpassing the performance of the individual precipitation products and two other merging methods (the simple linear regression model and the simple averaging). Among the three existing products, ERA5-Land exhibited the best performance in capturing daily precipitation, followed by GPM IMERG, while CHIRPS performed the worst. Regarding precipitation intensity, all three existing products and the RF-MEP merged dataset performed well in capturing light precipitation events with an intensity of less than 1 mm/day, which accounts for the majority (more than 70%) of occurrences. However, all datasets showed rather poor capability in capturing precipitation events beyond 1 mm/day, with the worst performance observed for extreme heavy precipitation events exceeding 50 mm/day. The RF-MEP approach significantly improves the detection ability for all precipitation intensities, except for the most extreme intensity (>50 mm/day), where only marginal improvement is observed. Analysis of the spatial pattern of precipitation estimates and the temporal bias of daily precipitation estimates further confirms the superior performance of the RF-MEP merged precipitation dataset over the three existing products.https://www.mdpi.com/2072-4292/15/17/4230precipitationrandom forestmergerainfall intensitysatellite productsreanalysis products |
| spellingShingle | Yongming Shi Cheng Chen Jun Chen Babak Mohammadi Majid Cheraghalizadeh Mohammed Abdallah Okan Mert Katipoğlu Haotian Li Zheng Duan Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China Remote Sensing precipitation random forest merge rainfall intensity satellite products reanalysis products |
| title | Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China |
| title_full | Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China |
| title_fullStr | Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China |
| title_full_unstemmed | Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China |
| title_short | Evaluation of the RF-MEP Method for Merging Multiple Gridded Precipitation Products in the Chongqing City, China |
| title_sort | evaluation of the rf mep method for merging multiple gridded precipitation products in the chongqing city china |
| topic | precipitation random forest merge rainfall intensity satellite products reanalysis products |
| url | https://www.mdpi.com/2072-4292/15/17/4230 |
| work_keys_str_mv | AT yongmingshi evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT chengchen evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT junchen evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT babakmohammadi evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT majidcheraghalizadeh evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT mohammedabdallah evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT okanmertkatipoglu evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT haotianli evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina AT zhengduan evaluationoftherfmepmethodformergingmultiplegriddedprecipitationproductsinthechongqingcitychina |