The Atmosphere and Climate Modeling - Introduction to Carbon Capture and Sequestration - page 78

Climate models

Figure 2.5.1 illustrates the basic climate model; a spherical grid is con-
structed in the computer that mimics the atmosphere. The number of grid
points we can use to describe our system depends on the size of the
computer that we can use. In Figure 2.5.2 the size of the grid for the dif-
ferent IPCC studies is shown. If we compare the fi rst studies in 1990 with
the more recent ones in 2007, the differences are striking in the amount
of detail one can include [2.2]. For example, in the FAR (1990) model it

Horizontal Grid
(Latitude-Longitude)

Vertical Grid
(Height or Pressure)

Physical Processes in a Model

solar
radiation

terrestrial
radiation

Atmosphere

advection

snow

momentum heat water sea ice

continent

mixed layer ocean

advection

Ocean

Figure 2.5.1 Solving the Navier-Stokes equations
A climate model involves solving the Navier-Stokes equations on a grid. The complica-
tion is that at each grid point there are different interactions between the atmosphere
and its environment. These differences include differences in solar radiation (e.g., day-
night), and location relative to land or water, each having different energy transfers (see
inset). Figure adapted from NOAA.