# CAM3¶

climlab wrappers for the NCAR CAM3 radiation code

Input arguments and diagnostics follow specifications in _Radiation

Example

Here is a quick example of setting up a single-column Radiative-Convective model with fixed relative humdity:

import climlab
alb = 0.25
#  State variables (Air and surface temperature)
state = climlab.column_state(num_lev=30)
#  Parent model process
rcm = climlab.TimeDependentProcess(state=state)
#  Fixed relative humidity
#  Couple water vapor to radiation
#  Couple everything together
#  Run the model
rcm.integrate_years(1)
#  Check for energy balance
print rcm.ASR - rcm.OLR

class climlab.radiation.cam3.cam3.CAM3(**kwargs)[source]

climlab wrapper for the CAM3 radiation code.

Attributes
depth

Depth at grid centers (m)

depth_bounds

Depth at grid interfaces (m)

diagnostics

input

lat

Latitude of grid centers (degrees North)

lat_bounds

Latitude of grid interfaces (degrees North)

lev

Pressure levels at grid centers (hPa or mb)

lev_bounds

Pressure levels at grid interfaces (hPa or mb)

lon

Longitude of grid centers (degrees)

lon_bounds

Longitude of grid interfaces (degrees)

timestep

The amount of time over which step_forward() is integrating in unit seconds.

Methods

 add_diagnostic(name[, value]) Create a new diagnostic variable called name for this process and initialize it with the given value. add_input(name[, value]) Create a new input variable called name for this process and initialize it with the given value. add_subprocess(name, proc) Adds a single subprocess to this process. add_subprocesses(procdict) Adds a dictionary of subproceses to this process. compute() Computes the tendencies for all state variables given current state and specified input. compute_diagnostics([num_iter]) Compute all tendencies and diagnostics, but don’t update model state. declare_diagnostics(diaglist) Add the variable names in inputlist to the list of diagnostics. declare_input(inputlist) Add the variable names in inputlist to the list of necessary inputs. integrate_converge([crit, verbose]) Integrates the model until model states are converging. integrate_days([days, verbose]) Integrates the model forward for a specified number of days. integrate_years([years, verbose]) Integrates the model by a given number of years. remove_diagnostic(name) Removes a diagnostic from the process.diagnostic dictionary and also delete the associated process attribute. remove_subprocess(name[, verbose]) Removes a single subprocess from this process. set_state(name, value) Sets the variable name to a new state value. set_timestep([timestep, num_steps_per_year]) Calculates the timestep in unit seconds and calls the setter function of timestep() step_forward() Updates state variables with computed tendencies. to_xarray([diagnostics]) Convert process variables to xarray.Dataset format.
_cam3_to_climlab(field)[source]

Output is either (KM, JM, 1) or (JM, 1). Transform this to…

• (KM,) or (1,) if JM==1

• (KM, JM) or (JM, 1) if JM>1

(longitude dimension IM not yet implemented).

_climlab_to_cam3(field)[source]

Prepare field with proper dimension order. CAM3 code expects 3D arrays with (KM, JM, 1) and 2D arrays with (JM, 1).

climlab grid dimensions are any of:
• (KM,)

• (JM, KM)

• (JM, IM, KM)

(longitude dimension IM not yet implemented here).

_compute_heating_rates()[source]

Computes energy flux convergences to get heating rates in unit $$\textrm{W}/ \textrm{m}^2$$.

This method should be over-ridden by daughter classes.

_prepare_arguments()[source]
class climlab.radiation.cam3.cam3.CAM3_LW(**kwargs)[source]
Attributes
depth

Depth at grid centers (m)

depth_bounds

Depth at grid interfaces (m)

diagnostics

input

lat

Latitude of grid centers (degrees North)

lat_bounds

Latitude of grid interfaces (degrees North)

lev

Pressure levels at grid centers (hPa or mb)

lev_bounds

Pressure levels at grid interfaces (hPa or mb)

lon

Longitude of grid centers (degrees)

lon_bounds

Longitude of grid interfaces (degrees)

timestep

The amount of time over which step_forward() is integrating in unit seconds.

Methods

 add_diagnostic(name[, value]) Create a new diagnostic variable called name for this process and initialize it with the given value. add_input(name[, value]) Create a new input variable called name for this process and initialize it with the given value. add_subprocess(name, proc) Adds a single subprocess to this process. add_subprocesses(procdict) Adds a dictionary of subproceses to this process. compute() Computes the tendencies for all state variables given current state and specified input. compute_diagnostics([num_iter]) Compute all tendencies and diagnostics, but don’t update model state. declare_diagnostics(diaglist) Add the variable names in inputlist to the list of diagnostics. declare_input(inputlist) Add the variable names in inputlist to the list of necessary inputs. integrate_converge([crit, verbose]) Integrates the model until model states are converging. integrate_days([days, verbose]) Integrates the model forward for a specified number of days. integrate_years([years, verbose]) Integrates the model by a given number of years. remove_diagnostic(name) Removes a diagnostic from the process.diagnostic dictionary and also delete the associated process attribute. remove_subprocess(name[, verbose]) Removes a single subprocess from this process. set_state(name, value) Sets the variable name to a new state value. set_timestep([timestep, num_steps_per_year]) Calculates the timestep in unit seconds and calls the setter function of timestep() step_forward() Updates state variables with computed tendencies. to_xarray([diagnostics]) Convert process variables to xarray.Dataset format.
class climlab.radiation.cam3.cam3.CAM3_SW(**kwargs)[source]
Attributes
depth

Depth at grid centers (m)

depth_bounds

Depth at grid interfaces (m)

diagnostics

input

lat

Latitude of grid centers (degrees North)

lat_bounds

Latitude of grid interfaces (degrees North)

lev

Pressure levels at grid centers (hPa or mb)

lev_bounds

Pressure levels at grid interfaces (hPa or mb)

lon

Longitude of grid centers (degrees)

lon_bounds

Longitude of grid interfaces (degrees)

timestep

The amount of time over which step_forward() is integrating in unit seconds.

Methods

 add_diagnostic(name[, value]) Create a new diagnostic variable called name for this process and initialize it with the given value. add_input(name[, value]) Create a new input variable called name for this process and initialize it with the given value. add_subprocess(name, proc) Adds a single subprocess to this process. add_subprocesses(procdict) Adds a dictionary of subproceses to this process. compute() Computes the tendencies for all state variables given current state and specified input. compute_diagnostics([num_iter]) Compute all tendencies and diagnostics, but don’t update model state. declare_diagnostics(diaglist) Add the variable names in inputlist to the list of diagnostics. declare_input(inputlist) Add the variable names in inputlist to the list of necessary inputs. integrate_converge([crit, verbose]) Integrates the model until model states are converging. integrate_days([days, verbose]) Integrates the model forward for a specified number of days. integrate_years([years, verbose]) Integrates the model by a given number of years. remove_diagnostic(name) Removes a diagnostic from the process.diagnostic dictionary and also delete the associated process attribute. remove_subprocess(name[, verbose]) Removes a single subprocess from this process. set_state(name, value) Sets the variable name to a new state value. set_timestep([timestep, num_steps_per_year]) Calculates the timestep in unit seconds and calls the setter function of timestep() step_forward() Updates state variables with computed tendencies. to_xarray([diagnostics]) Convert process variables to xarray.Dataset format.
climlab.radiation.cam3.cam3.init_cam3(mod)[source]