"In atmospheric science, an atmospheric model is a mathematical model constructed around the full set of primitive, dynamical equations which govern atmospheric motions."
The use of computer models and simulations to understand atmospheric processes and predict future trends.
Thermodynamics: The study of heat and energy transfer in the atmosphere, including the behavior of gases under different conditions.
Radiative Transfer: The study of how radiation, including sunlight, interacts with the atmosphere, including scattering and absorption.
Dynamics: The study of how the motion of air masses affects atmospheric conditions, including temperature, pressure, and wind.
Atmospheric Composition: The study of the chemical makeup of the atmosphere, including the distribution of gases, aerosols, and pollutants.
Clouds: The study of how clouds form and the role they play in atmospheric processes, including reflecting and absorbing radiation and contributing to precipitation.
Air Quality: The study of the concentration and distribution of pollutants in the atmosphere, including the effects of human activities on air quality.
Climate Change: The study of how changes in atmospheric composition, including greenhouse gases, are affecting global climate patterns.
Meteorology: The study of short-term atmospheric conditions, including weather patterns and severe weather events.
Oceanography: The study of the interaction between the atmosphere and the oceans, including the role of oceans in regulating climate.
Numerical Modeling: The use of mathematical models to predict atmospheric conditions and inform environmental decision-making.
Chemical transport models (CTMs): CTMs are the most widely used type of atmospheric modeling. They focus on the transport and transformation of chemical species in the atmosphere. These models can simulate the dispersion of pollutants and their chemical reactions.
Photochemical models: Photochemical models deal with the chemical reactions that are triggered by ultraviolet radiation from the sun. These models focus on the formation and distribution of photochemical pollutants, such as ozone and nitrogen oxides.
Aerosol models: Aerosol models are used to study the formation, transport, and effect of atmospheric particles, including dust, sea salt, and sulfate. These models simulate the sources, atmospheric transport, and deposition of aerosols.
Emission inventories: Emission inventories are databases that contain estimates of human-made and natural emissions of pollutants into the atmosphere. These inventories are important for the development of atmospheric models and for predicting future air quality.
Global models: Global models simulate the atmospheric chemistry on a global scale. They can be used to investigate the long-range transport of pollutants, climate change, and the impact of human activities on the global environment.
Regional models: Regional models focus on the atmospheric chemistry on a smaller scale, such as a city or a region. These models can provide detailed information on local air quality and the sources of pollutants.
Boundary layer models: Boundary layer models simulate the atmospheric chemistry in the lower part of the atmosphere, where most of the air pollution occurs. These models focus on the transport and dispersion of pollutants near the surface.
Three-dimensional models: Three-dimensional models simulate the atmospheric chemistry in three dimensions, accounting for the complex interactions between chemicals, temperature, and pressure. These models can provide detailed information on the spatial distribution of pollutants.
Community models: Community models are collaborative efforts between multiple organizations and researchers to create a comprehensive and shared atmospheric model. These models incorporate a range of components, such as emissions, meteorology, and atmospheric chemistry.
"They can supplement these equations with parameterizations for turbulent diffusion, radiation, moist processes (clouds and precipitation), heat exchange, soil, vegetation, surface water, the kinematic effects of terrain, and convection."
"Most atmospheric models are numerical, i.e. they discretize equations of motion."
"They can predict microscale phenomena such as tornadoes and boundary layer eddies, sub-microscale turbulent flow over buildings, as well as synoptic and global flows."
"The horizontal domain of a model is either global, covering the entire Earth, or regional (limited-area), covering only part of the Earth."
"The different types of models run are thermotropic, barotropic, hydrostatic, and nonhydrostatic."
"Therefore, numerical methods obtain approximate solutions."
"Global models often use spectral methods for the horizontal dimensions and finite-difference methods for the vertical dimension."
"Regional models usually use finite-difference methods in all three dimensions."
"Forecasts are computed using mathematical equations for the physics and dynamics of the atmosphere."
"These equations are nonlinear."
"These equations are impossible to solve exactly."
"Model output statistics use climate information, output from numerical weather prediction, and current surface weather observations."
"Model output statistics develop statistical relationships which account for model bias and resolution issues."
"Some of the model types make assumptions about the atmosphere which lengthens the time steps used and increases computational speed."
"Regional models usually use finite-difference methods in all three dimensions."
"They can predict microscale phenomena such as tornadoes and boundary layer eddies, sub-microscale turbulent flow over buildings, as well as synoptic and global flows."
"They can supplement these equations with parameterizations for turbulent diffusion, radiation, moist processes (clouds and precipitation), heat exchange, soil, vegetation, surface water, the kinematic effects of terrain, and convection."
"The horizontal domain of a model is either global, covering the entire Earth, or regional (limited-area), covering only part of the Earth."
"The different types of models run are thermotropic, barotropic, hydrostatic, and nonhydrostatic."