Thresh model is a precipitation tracking program, which is used to calculate various precipitation indexes to compare with the existing or experimental threshold of landslide occurrence. The program calculates the cumulative precipitation, precipitation intensity and precipitation duration, and compares the results with the threshold value to determine the threshold value used in landslide early warning. This command-line program is used with Python and shell scripts for input files and visualization results.

Anuga hydrodynamic modeling tool can build complex 2D hydrodynamic model. For example, simulate the fracture of a dam or the impact of natural disasters such as storms and tsunamis. A research area must be designated as a triangular unit, if applicable, to determine topography and bathymetric measurements, friction, initial water level values (Anuga referred to as the first stage), boundary conditions and forces such as rainfall, river flow, wind stress and pressure gradient networks. Anuga simulated the evolution of water depth and horizontal momentum with time in each element by solving the shallow water wave equation and using the finite volume method.

Distributed hydrological model, water and energy prediction, geotop can be applied to very complex terrain, and integrates all surface energy balance conditions except water balance. For saturated and unsaturated subsurface flow, 3D Richard equation is adopted to realize accurate input of radiation parameters to obtain surface temperature.

Topoflow is a powerful and spatially distributed hydrological model with a user-friendly click interface. Its main purpose is to simulate many different physical processes in a watershed, and its goal is to accurately predict how various hydrological variables will evolve in response to climate forces.

HSPF (hydraulic simulation program - FORTRAN) model is a mathematical model developed by the U.S. Environmental Protection Agency (EPA). It is used for continuous simulation of hydrological and water quality processes in a large watershed under natural and artificial conditions. The model is written in FORTRAN language and based on Stanford hydrological model. It can comprehensively simulate runoff, soil loss, pollutant transport, river hydraulic and other processes, and is widely used in the scenario simulation of watershed water environment effects of climate change and land use change. The model is an excellent representative of semi distributed hydrological and water quality model, HSPF model is widely used in foreign countries. HSPF model includes perlnd, implnd and rchres to simulate the hydrology and water quality of permeable section, impervious section and surface water body respectively. Generally speaking, HSPF model plays an important role in the simulation of hydrology and water quality process in foreign countries, as well as scenario analysis involving climate change and land use impact, But the application of this model in China is very limited