eprintid: 10066675 rev_number: 20 eprint_status: archive userid: 608 dir: disk0/10/06/66/75 datestamp: 2019-02-08 10:52:04 lastmod: 2021-09-30 22:46:03 status_changed: 2019-02-08 10:52:04 type: article metadata_visibility: show creators_name: Huang, J creators_name: Ma, H creators_name: Sedano, F creators_name: Lewis, P creators_name: Liang, S creators_name: Wu, Q creators_name: Su, W creators_name: Zhang, X creators_name: Zhu, D title: Evaluation of regional estimates of winter wheat yield by assimilating three remotely sensed reflectance datasets into the coupled WOFOST-PROSAIL model ispublished: pub divisions: UCL divisions: B03 divisions: C03 divisions: F26 keywords: WOFOST, PROSAIL, Canopy reflectance, Data assimilation, Winter wheat yield estimation note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. abstract: To estimate regional-scale winter wheat (Triticum aestivum) yield, we developed a data-assimilation scheme that assimilates remotely sensed reflectance into a coupled crop growth–radiative transfer model. We generated a time series of 8-day, 30-m-resolution synthetic Kalman Smoothed reflectance by combining MODIS surface reflectance products with Landsat surface reflectance using a KS algorithm. We evaluated the assimilation performance using datasets with different spatial and temporal scales (e.g., three dates for the 30-m Landsat reflectance, 8-day and 1-km MODIS surface reflectance, and 8-day and 30-m synthetic KS reflectance) into the coupled WOFOST–PROSAIL model. Then we constructed a four-dimensional variational data assimilation (4DVar) cost function to account for differences between the observed and simulated reflectance. We used the shuffled complex evolution–University of Arizona (SCE-UA) algorithm to minimize the 4DVar cost function and optimize important input parameters of the coupled model. The optimized parameters were used to drive WOFOST and estimate county-level winter wheat yield in a region of China. By assimilating the synthetic KS reflectance data, we achieved the most accurate yield estimates (R2 = 0.44, 0.39, and 0.30; RMSE = 598, 1288, and 595 kg/ha for 2009, 2013, and 2014, respectively), followed by Landsat reflectance (R2 = 0.21, 0.22, and 0.33; RMSE = 915, 1422, and 637 kg/ha for 2009, 2013, and 2014, respectively) and MODIS reflectance (R2 = 0.49, 0.05, and 0.22; RMSE = 1136, 1468, and 700 kg/ha for 2009, 2013, and 2014, respectively) at the county level. Thus, our method improves the reliability of regional-scale crop yield estimates. date: 2019-01 date_type: published publisher: ELSEVIER SCIENCE BV official_url: https://doi.org/10.1016/j.eja.2018.10.008 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green article_type_text: Article verified: verified_manual elements_id: 1616565 doi: 10.1016/j.eja.2018.10.008 language_elements: English lyricists_name: Lewis, Philip lyricists_name: Wu, Qingling lyricists_id: PELEW26 lyricists_id: QQWHW55 actors_name: Wu, Qingling actors_id: QQWHW55 actors_role: owner full_text_status: public publication: European Journal of Agronomy volume: 102 pagerange: 1-13 pages: 13 issn: 1873-7331 citation: Huang, J; Ma, H; Sedano, F; Lewis, P; Liang, S; Wu, Q; Su, W; ... Zhu, D; + view all <#> Huang, J; Ma, H; Sedano, F; Lewis, P; Liang, S; Wu, Q; Su, W; Zhang, X; Zhu, D; - view fewer <#> (2019) Evaluation of regional estimates of winter wheat yield by assimilating three remotely sensed reflectance datasets into the coupled WOFOST-PROSAIL model. European Journal of Agronomy , 102 pp. 1-13. 10.1016/j.eja.2018.10.008 <https://doi.org/10.1016/j.eja.2018.10.008>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10066675/1/PDFsam_EURAGR7797R2.pdf