Climate model

Numerical climate models (or climate system models) are <a href="/facts/Mathematical_model/CGhyuxgz">mathematical models</a> that can simulate the interactions of important drivers of <a href="/facts/Climate/f57XrNFU">climate</a>. These drivers are the <a href="/facts/Earth%2527s_atmosphere/FV97Am25">atmosphere</a>, <a href="/facts/Ocean/8W8lYgjD">oceans</a>, <a href="/facts/Land_surface/r2lduLeI">land surface</a> and <a href="/facts/Cryosphere/0taEf85w">ice</a>. Scientists use climate models to study the dynamics of the <a href="/facts/Climate_system/5JyveutF">climate system</a> and to make projections of future climate and of <a href="/facts/Climate_change/rEN4BDE7">climate change</a>. Climate models can also be qualitative (i.e. not numerical) models and contain narratives, largely descriptive, of possible futures.
Climate models take account of incoming <a href="/facts/Energy/wd8PrQM7">energy</a> from the Sun as well as outgoing energy from Earth. An imbalance results in a <a href="/facts/First_law_of_thermodynamics/hjL95WCr">change in temperature</a>. The incoming energy from the Sun is in the form of short wave <a href="/facts/Electromagnetic_radiation/Ynx7ujCW">electromagnetic radiation</a>, chiefly <a href="/facts/Visible_spectrum/frPBh8o5">visible</a> and short-wave (near) <a href="/facts/Infrared/44XdJNcc">infrared</a>. The outgoing energy is in the form of long wave (far) <a href="/facts/Infrared/44XdJNcc">infrared</a> electromagnetic energy. These processes are part of the <a href="/facts/Greenhouse_effect/LGdNYYj3">greenhouse effect</a>.
Climate models vary in complexity. For example, a simple <a href="/facts/Radiant_heat/1PD9jtCv">radiant heat</a> transfer model treats the Earth as a single point and averages outgoing energy. This can be expanded vertically (radiative-convective models) and horizontally. More complex models are the coupled atmosphere–ocean–<a href="/facts/Sea_ice/tgTbCYwg">sea ice</a> <a href="/facts/Global_climate_model/6QUar9RF">global climate models</a>. These types of models solve the full equations for mass transfer, <a href="/facts/Energy_transfer/wd8PrQM7">energy transfer</a> and radiant exchange. In addition, other types of models can be interlinked. For example <a href="/facts/Earth_system_model/dG9qMCbX">Earth System Models</a> include also <a href="/facts/Land_use/BAMqwQcG">land use</a> as well as <a href="/facts/Land_use_change/BAMqwQcG">land use changes</a>. This allows researchers to predict the interactions between climate and <a href="/facts/Ecosystems/kVE8mSmR">ecosystems</a>.
Climate models are systems of <a href="/facts/Differential_equation/9MGbE3Ca">differential equations</a> based on the basic laws of <a href="/facts/Physics/a7aH2y08">physics</a>, <a href="/facts/Fluid_dynamics/y7uzSCfg">fluid motion</a>, and <a href="/facts/Chemistry/SrNqkGVm">chemistry</a>. Scientists divide the planet into a 3-dimensional grid and apply the basic equations to those grids. <a href="/facts/Atmospheric_model/j7epJxSw">Atmospheric models</a> calculate <a href="/facts/Winds/Nt0QIu5B">winds</a>, <a href="/facts/Heat_transfer/1IV3WbFL">heat transfer</a>, <a href="/facts/Radiation/RwMocyeq">radiation</a>, <a href="/facts/Relative_humidity/Nwb28VlT">relative humidity</a>, and surface <a href="/facts/Hydrology/Xh727cnE">hydrology</a> within each grid and evaluate interactions with neighboring points. These are coupled with <a href="/facts/Oceanic_model/lgQL2yeB">oceanic models</a> to simulate <a href="/facts/Climate_variability_and_change/D3X6Ulbu">climate variability and change</a> that occurs on different timescales due to shifting <a href="/facts/Ocean_current/vfwdGwPY">ocean currents</a> and the much larger <a href="/facts/Ocean_heat_content/RDwuuFnm">heat storage capacity</a> of the global ocean. <a href="/facts/Climate_forcing/5JyveutF">External drivers</a> of change may also be applied. Including an <a href="/facts/Ice-sheet_model/8mf054ou">ice-sheet model</a> better accounts for long term effects such as <a href="/facts/Sea_level_rise/Pb5MGJxb">sea level rise</a>.

Climate model open-in-new

Climate model