#include <PrecipitationScaling.hh>

Inheritance diagram for pism::atmosphere::PrecipitationScaling:

Public Member Functions
	PrecipitationScaling (std::shared_ptr< const Grid > g, std::shared_ptr< AtmosphereModel > in)

virtual	~PrecipitationScaling ()=default

Public Member Functions inherited from pism::atmosphere::AtmosphereModel
	AtmosphereModel (std::shared_ptr< const Grid > g)

	AtmosphereModel (std::shared_ptr< const Grid > g, std::shared_ptr< AtmosphereModel > input)

virtual	~AtmosphereModel ()=default

void	init (const Geometry &geometry)

void	update (const Geometry &geometry, double t, double dt)

const array::Scalar &	precipitation () const
	Sets result to the mean precipitation, in "kg m-2 second-1".

const array::Scalar &	air_temperature () const
	Sets result to the mean near-surface air temperature, in kelvin.

void	begin_pointwise_access () const

void	end_pointwise_access () const

void	init_timeseries (const std::vector< double > &ts) const

void	precip_time_series (int i, int j, std::vector< double > &result) const
	Sets a pre-allocated N-element array "result" to the time-series of ice-equivalent precipitation (m/s) at the point i,j on the grid.

void	temp_time_series (int i, int j, std::vector< double > &result) const
	Sets a pre-allocated N-element array "result" to the time-series of near-surface air temperature (kelvin) at the point i,j on the grid. Times (in years) are specified in ts. NB! Has to be surrounded by begin_pointwise_access() and end_pointwise_access()

Public Member Functions inherited from pism::Component
	Component (std::shared_ptr< const Grid > grid)

virtual	~Component ()=default

DiagnosticList	diagnostics () const

TSDiagnosticList	ts_diagnostics () const

std::shared_ptr< const Grid >	grid () const

const Time &	time () const

const Profiling &	profiling () const

void	define_model_state (const File &output) const
	Define model state variables in an output file.

void	write_model_state (const File &output) const
	Write model state variables to an output file.

MaxTimestep	max_timestep (double t) const
	Reports the maximum time-step the model can take at time t.

Protected Member Functions
void	init_impl (const Geometry &geometry)

void	update_impl (const Geometry &geometry, double t, double dt)

void	init_timeseries_impl (const std::vector< double > &ts) const

const array::Scalar &	precipitation_impl () const

void	precip_time_series_impl (int i, int j, std::vector< double > &values) const

Protected Member Functions inherited from pism::atmosphere::AtmosphereModel
virtual void	define_model_state_impl (const File &output) const
	The default (empty implementation).

virtual void	write_model_state_impl (const File &output) const
	The default (empty implementation).

virtual MaxTimestep	max_timestep_impl (double my_t) const

virtual const array::Scalar &	air_temperature_impl () const

virtual void	begin_pointwise_access_impl () const

virtual void	end_pointwise_access_impl () const

virtual void	temp_time_series_impl (int i, int j, std::vector< double > &result) const

virtual DiagnosticList	diagnostics_impl () const

virtual TSDiagnosticList	ts_diagnostics_impl () const

Protected Member Functions inherited from pism::Component
void	regrid (const std::string &module_name, array::Array &variable, RegriddingFlag flag=NO_REGRID_WITHOUT_REGRID_VARS)

Protected Attributes
double	m_exp_factor

std::shared_ptr< ScalarForcing >	m_forcing

std::vector< double >	m_scaling_values

std::shared_ptr< array::Scalar >	m_precipitation

Protected Attributes inherited from pism::atmosphere::AtmosphereModel
std::vector< double >	m_ts_times

std::shared_ptr< AtmosphereModel >	m_input_model

Protected Attributes inherited from pism::Component
const std::shared_ptr< const Grid >	m_grid
	grid used by this component

const Config::ConstPtr	m_config
	configuration database used by this component

const units::System::Ptr	m_sys
	unit system used by this component

const Logger::ConstPtr	m_log
	logger (for easy access)

Additional Inherited Members
Protected Types inherited from pism::Component
enum	RegriddingFlag { REGRID_WITHOUT_REGRID_VARS , NO_REGRID_WITHOUT_REGRID_VARS }
	This flag determines whether a variable is read from the `-regrid_file` file even if it is not listed among variables in `-regrid_vars`. More...

Static Protected Member Functions inherited from pism::atmosphere::AtmosphereModel
static std::shared_ptr< array::Scalar >	allocate_temperature (std::shared_ptr< const Grid > grid)

static std::shared_ptr< array::Scalar >	allocate_precipitation (std::shared_ptr< const Grid > grid)

Detailed Description

Scaling precipitation using air temperature offsets

This class implements the adjustment used to capture the influence of changing air temperature on precipitation. It uses scalar temperature offsets read from a file as an input.

$P_{G}(x,y,t) = P_{G}(x,y,0)exp\left[\frac{0.169}{d}\left({\Delta}T(t)+ {\Delta}T_{SC}(t)\right)\right]$

where $P_G(x,y,0)$ is the precipitation for the present Greenland ice sheet, obtained from the atmosphere model used as an input of this class. The time dependent precipitation is $P_G(x,y,t)$ , $d$ is the ${\delta}_{18}$ conversion factor of $2.4^{\circ}C/\frac{0}{00}$ , and ${\Delta}T_{SC}$ is a correction term for the change of altitude of the central dome during the Greenland ice sheet's evolution. The coefficient " @f$ 0.169/d @f$ " corresponds to a 7.3% change of precipitation rate for every $1^{\circ}C$ of temperature change (Huybrechts et al. 2002).

One possible scheme for ${\Delta}T_{SC}(t)$ (used in PISM) is to take it to be zero, which regards the height correction as belonging to the set of uncertainties related to the conversion between isotopic and temperature signals.

Definition at line 56 of file PrecipitationScaling.hh.

The documentation for this class was generated from the following files:

src/coupler/atmosphere/PrecipitationScaling.hh
src/coupler/atmosphere/PrecipitationScaling.cc

Public Member Functions

Protected Member Functions

Protected Attributes

Additional Inherited Members

Detailed Description