Ramms:: avalanche model is used to simulate avalanche in complex terrain. The model has been widely used in avalanche hazard studies in Switzerland. The ramms:: avalanche model combines state-of-the-art digital solutions with helpful input features and friendly visualization tools. Many of the input and output features are optimized, enabling users to easily modify dangerous scenarios and control simulation results. The core of the program is an effective second-order numerical solution, that is, the depth averaged avalanche dynamic equation. In the 3D digital terrain model, the velocity and velocity of avalanche are calculated. Using the GIS type drawing feature, you can easily specify a single or multiple publishing areas. Users can get useful overview information about the simulation, including important information about the release area (average slope, total capacity), traffic behavior (maximum flow and height), and stop behavior (mass flow). Maps and remote sensing images can be superimposed on terrain models to help determine input conditions and calibrate models based on known events. The ramms:: avalanche model has been used in more than 70 places around the world, and the software has been successfully applied to high mountain areas such as the Alps, Himalayas, Andes, Rockies, tatare and other areas.

Class model, as the "second generation" surface model that people need, was developed for Canadian GCM in the late 1980s. The model will fully deal with the effects of vegetation, snow cover and soil on the heat and temperature of the atmosphere. Various land surface parameterization schemes are compared in international projects. The class model is tested in the coupling model with GCM and various experiments with pilps. In such an operating environment, class is proved to perform quite well.

Glims model is jointly developed by University of Georgia and USDA-ARS, its predecessor is creams, which is mainly used for small-scale simulation. The water quality items that can be simulated include sediment, nitrate nitrogen, ammonia nitrogen, phosphorus nitrate, ammonia nitrogen, total nitrogen, total phosphorus, etc. The modified SCS curve number method was used to simulate rainfall runoff, and the priestly Taylor or penman Monteith method was used to simulate evaporation. By simulating the effects of ammoniation, nitrification, denitrification, volatilization, absorption and fixation, the nitrogen factor was simulated by combining empirical or semi empirical formula with the model. A long-term soil erosion model developed by Sharpley et al. Was used to simulate phosphorus. The pesticide composition was mainly aimed at the interaction of pesticide characteristics, soil texture, climate impact, management strategy, surface runoff leakage and adhesion. The model also simulated the pesticide transport in the rhizosphere.

The UNMIX model is a mathematical receptor model developed by scientists from the U.S. Environmental Protection Agency. It provides scientific support for the development and review of air and water quality standards, exposure studies and environmental forensics. UNMIX can analyze a wide range of environmental sample data: sediment, wet deposition, surface water, ambient air and indoor air.