Cryosphere and Hydrology
Objectives:The main objective is to develop prototypes of real-time remote sensing (RS) land data assimilation systems (LDAS) for monitoring the water cycle in the silk road endorheic river basins and EUROCORDEX-domain. This will provide a synergic and innovative way to integrate RS data from NRSCC and ESA into terrestrial system models for better quantifying the water cycle at the watershed/regional scale.The objective will be achieved through the following sub-objectives:ÔÇó Retrieval of key water cycle variables from multi-source RS data (WP1);ÔÇó Development of real time RS LDAS to integrate RS data into terrestrial system models (WP2);ÔÇó Calibration/validation of terrestrial system models using RS retrievals of key water cycle variables (WP3);ÔÇó Parameter estimations for terrestrial system models based on the LDAS (WP3);ÔÇó Closing and quantifying the water cycle at the watershed/regional scale based on the LDAS (WP4).Methods:Two LDAS will be developed in the project, one for the silk road endorheic river basins (LDAS_Silk) and one for EUROCORDEX-domain (LDAS_EU). LDAS_Silk will be based on the recently developed watershed system model (Li et al., 2018a,b) and a common software for nonlinear and non-Gaussian land data assimilation (ComDA, Liu et al., 2020). The watershed system model is mainly composed of i) a distributed eco-hydrological model that integrates the glacier, snow, and frozen soil processes (GBEHM) (Yang et al., 2015), and ii) a Hydrological-Ecological Integrated watershed-scale FLOW model (HEIFLOW) (Tian et al., 2015). LDAS_EU will be based on the recently developed Terrestrial System Modeling Platform (TSMP) (Shrestha et al., 2014) and Parallel Data Assimilation Framework (PDAF) (Nerger and Hiller, 2013). The TSMP-PDAF is a modular high-performance data assimilation framework for an integrated subsurface-land surface-atmosphere model (Kurtz et al., 2016). TSMP comprises three component models: i) the Consortium for Small-scale Modeling (COSMO) atmospheric model (Baldauf et al., 2011), ii) the Community Land Model (CLM) (Oleson et al., 2008), and iii) the hydrological model ParFlow (Kollet and Maxwell, 2006). The TSMP can be run in three modes: fully coupled (COSMO + CLM + ParFlow), partly coupled (CLM + ParFlow/CLM + COSMO) or uncoupled. Comparison will be made between the performances of the LDAS_Silk and LDAS_EU.Multi-source RS data, from visible to thermal infrared and microwave, will be used to retrieve key ecohydrological variables, such as evapotranspiration (ET), snow coverage area (SCA), snow water equivalent (SWE), snow depth (SD), soil moisture (SM), lake and glacier extents, irrigation, and vegetation density and structure. These data will be used as forcing data, calibration and validation data, and for assimilation into the two LDAS. The developed LDAS will estimate the different components of the water cycle (ET, SM, streamflow, SWE and groundwater dynamic) at the watershed/regional scale on a daily basis and a spatial resolution of 10 km.Deliverables: ÔÇó Retrievals of key ecohydrological variables, including vegetation parameters, SM, SWE, irrigation, lake and glacier extents from RS data (WP1);ÔÇó Development of LDAS_Silk for the silk road endorheic river basins (WP2);ÔÇó Development of LDAS_EU for the EUROCORDEX-domain (WP2);ÔÇó Calibration/validation procedures for the LDAS_Silk and the LDAS_EU (WP3);ÔÇó Estimation of different components of the water cycle for the silk road endorheic river basins and EUROCORDEX-domain produced by the developed LDAS (WP4).Source of Funding:ÔÇó Strategic Priority Research Program of Chinese Academy of Sciences (Grant numbers: XDA19070104 and XDA20100100);ÔÇó Research unit FOR2131 (Data Assimilation for Improved Characterization of Fluxes Across Compartmental Interfaces) of the German Science Foundation;ÔÇó European Union H2020 project EoCoE (Energy oriented center of excellence).
