«Mathematical modeling of geophysical processes: direct and inverse problems»

The seminar is devoted to the consideration of various aspects of mathematical modeling of physical processes in the atmosphere, hydrosphere and active layer of land, associated with solving problems arising in the study of the problems of climate change and the natural environment.

Seminar Organizing Committee

PROGRAM

Modeling suspended carbon in rivers: conceptual framework, implementation experience, and development prospects within the framework of the active layer model.

As a result of erosion processes in river basins, soil degradation products migrate from slopes along the channel network to receiving water bodies. This phenomenon, mechanical migration, is considered in geochemistry as a key agent for the transport of a wide range of chemical elements and compounds, including significant quantities of suspended organic carbon (SOC). Soil degradation is determined by slope (soil erosion) and channel (riverbank erosion). Therefore, SOC transport modeling relies on a component-by-component assessment of the sediment balance components of a river basin. This report discusses a conceptual framework for modeling SOC flows in river basins. The model consists of a module for calculating soil (basin) erosion based on the RUSLE (revised universal soil loss equation)—a parametric distributed model that calculates the volume of total loss in a catchment due to rainfall and snowmelt erosion—and estimates the sediment delivery coefficient based on the slope flow transport capacity. At the current stage of model development, empirical data are used to estimate the mass of material entering channels as a result of bank erosion, as well as the amount of material accumulation in the channel and floodplain. These calculation blocks are combined with carbon content data (C_(org)) from the SOIL GRIDS database.

Test calculations of the annual suspended carbon input into large Siberian reservoirs were performed in the Rstudio software environment, using the R programming language and the terra, dplyr, sf, and rusleR libraries. Calibration and verification of the calculations were performed using data on POC input into the Krasnoyarsk Reservoir with the Yenisei, Abakan, and Tuba river discharges, as well as POC data in Siberian rivers collected in recent years. Various model implementation options are considered, taking into account different POC transport processes within the river basin. The use of the SOIL GRIDS database determines the high uncertainty in estimating the carbon content in soils of eroding banks, making it crucial to parameterize the input data on carbon content in soils and riverbeds. However, given the existing global experience in implementing sediment runoff modeling in hydrological basin models (e.g., the SWAT model), the proposed algorithm appears promising for inclusion in the TERM active land layer model.

 The seminar also will be held in the form of a webinar on the Zoom platform.

Topic: семинар "Математическое моделирование геофизических процессов: прямые и обратные задачи".

Time: Feb 12, 2026 05:15 PM Moscow (GMT+3)

Join Zoom Meeting (Meeting ID: 834 7880 8646, Passcode: 632609)

Video recordings of the seminar are available on our youtube channel.

For communication on all issues related to the work of the seminar, please contact the academic secretary Yuliya Yarynich at julia.yarinich@srcc.msu.ru