Detailed Description

Canopy data used as a pointer in the SnowStation structure.

INSTANTANEOUS VARIABLES
1. Canopy "state" variables, and some auxiliaries
2. Properties which could be given here or as a parameter field
3. Aerodynamic resistances
CUMULATED/AVERAGE VARIABLES
cumulated between time series output timesteps - these variables can be moved or mirrored in a canopy "surface" data structure
1. Albedo and similar auxiliaries
2. Radiation fluxes
3. Canopy turbulent heat fluxes
4. Canopy evaporative fluxes
5. Canopy mass fluxes

#include <DataClasses.h>

Public Member Functions
	CanopyData ()

void	initialize (const SN_SNOWSOIL_DATA &SSdata, const bool useCanopyModel, const bool isAlpine3D)
	Initialize all the CData elements value with values by default or with values read from the SNO file. This function is called in SnowStation::initialize, whch is called by XXX in the main(). More...

void	reset (const bool &cumsum_mass)

void	initializeSurfaceExchangeData ()
	Function called to initialize the canopy "Surface" exchange data (to enable accumulated mass and energy fluxes) More...

void	multiplyFluxes (const double &factor)
	If multiple fluxes have been summed over multiple time steps, the fluxes then need to be averaged by the number of steps. The albedos are also averaged in this method. More...

const std::string	toString () const

Public Attributes
double	int_cap_snow

double	int_cap_rain
	Specific interception capacity for rain (I_LAI) (mm/LAI) More...

double	interception_timecoef

double	can_alb_dry
	RADIATION BALANCE. More...

double	can_alb_wet

double	can_alb_snow

double	krnt_lai

double	can_diameter

double	biomass_heat_capacity

double	biomass_density

double	lai_frac_top_default

double	trunk_frac_height

double	trunkalb

double	et

bool	canopy_stabilitycorrection

double	roughmom_to_canopyheight_ratio
	Ratio between canopy height and roughness length. More...

double	displ_to_canopyheight_ratio
	As above for displacement height. More...

double	raincrease_snow

double	canopytemp_maxchange_perhour
	Maximum allowed canopy temperature change (K hr-1) More...

double	roughheat_to_roughmom_ratio
	(~=1, but Not allowed to be exactly 1) More...

double	can_ch0
	minimum heat exchange (Wm-2K-1) at zero wind More...

double	can_rs_mult
	1+CAN_RS_MULT = maximum factor to increase Cdata->rs below canopy More...

double	rsmin
	TRANSPIRATION. More...

double	f3_gd
	gd (Pa-1) parameter for canopy surface resistance response to vapour pressure: More...

double	rootdepth
	Root depth, determining the soil layers influenced by root water uptake. More...

double	wp_fraction
	Wilting point, defined as a fraction of water content at field capacity (-) More...

double	h_wilt
	Wilting point pressure head, when using Richards equation for soil. More...

double	storage
	intercepted water (mm or kg m-2) More...

double	temp
	temperature (K) More...

double	sigf
	radiation transmissivity (1) More...

double	ec
	longwave emissivity (1) More...

double	lai

double	z0m

double	z0h

double	zdispl

double	height

double	direct_throughfall

double	ra
	from canopy air to reference height More...

double	rc
	from canopy to canopy air More...

double	rs
	from subsurface to canpopy air More...

double	rstransp
	stomatal surface resistance for transpiration More...

double	canopyalb
	canopy albedo [-] More...

double	totalalb
	total albedo above canopy and snow/soil surface [-] More...

double	wetfraction
	fraction of canopy covered by interception [-] More...

double	intcapacity
	maximum interception storage [mm] More...

double	rswrac
	upward shortwave above canopy More...

double	iswrac
	downward shortwave radiation above canopy More...

double	rswrbc
	upward shortwave below canopy More...

double	iswrbc
	downward shortwave radiation below canopy More...

double	ilwrac
	downward longwave radiation ABOVE canopy More...

double	rlwrac
	upward longwave radiation ABOVE canopy More...

double	ilwrbc
	downward longwave radiation BELOW canopy More...

double	rlwrbc
	upward longwave radiation BELOW canopy More...

double	rsnet
	net shortwave radiation More...

double	rlnet
	net longwave radiation More...

double	sensible

double	latent

double	latentcorr

double	transp

double	intevap

double	interception

double	throughfall

double	snowunload

double	snowfac
	snowfall above canopy More...

double	rainfac
	rainfall above canopy More...

double	liquidfraction

double	sigftrunk
	radiation interception cross section for trunk layer () More...

double	Ttrunk
	trunk temperature (K) More...

double	CondFluxCanop
	biomass heat storage flux towards Canopy (if 1L) towards Leaves (if 2L). (>0 towards canopy) More...

double	CondFluxTrunks
	biomass heat storage flux towards Trunks (if 2L) More...

double	LWnet_Trunks
	net LW to trunks (>0 towards trunks) More...

double	SWnet_Trunks
	net SW to trunks (>0 towards trunks) More...

double	QStrunks
	sensible heat flux from trunks (>0 if heat lost from trunk) More...

double	forestfloor_alb
	albedo of the forest floor More...

double	BasalArea
	basal area of trees on the stand More...

double	HMLeaves
	Leaves heat mass (J K-1 /m2 ground surface) More...

double	HMTrunks
	Trunks heat mass (J K-1 /m2 ground surface) More...

Friends
std::ostream &	operator<< (std::ostream &os, const CanopyData &data)

std::istream &	operator>> (std::istream &is, CanopyData &data)

Constructor & Destructor Documentation

◆ CanopyData()

CanopyData::CanopyData ( )

inline

Member Function Documentation

◆ initialize()

void CanopyData::initialize	(	const SN_SNOWSOIL_DATA &	SSdata,
		const bool	useCanopyModel,
		const bool	isAlpine3D
	)

Initialize all the CData elements value with values by default or with values read from the SNO file. This function is called in SnowStation::initialize, whch is called by XXX in the main().

Parameters

SSdata	soil data SN_SNOWSOIL_DATA& SSdata created in the main.
useCanopyModel	set to true if the canopy model is used
isAlpine3D	set to true when calling from Alpine3D in order to prevent the generation of warnings

Author: Adrien Michel

Specific interception capacity for rain (I_LAI) (mm/LAI)

Coef in interception function, see (Pomeroy et al,1998) where a value of 0.7 was found to be appropriate for hourly time-step, but smaller time steps require smaller values, 0.5 was found reasoanble by using the SnowMIP2 data (2007-12-09)

RADIATION BALANCE

TURBULENT HEAT EXCHANGE Stab. corr. aerodyn. resist. above and below canopy: 0=off and 1=on (Monin-Obukhov formulation)

Ratio between canopy height and roughness length

As above for displacement height

Fractional increase of aerodynamic resistance for evaporation of intercepted snow.

10.0 from Koivusalo and Kokkonen (2002)
8.0 calibration with Alptal data

Maximum allowed canopy temperature change (K hr-1)

(~=1, but Not allowed to be exactly 1)

minimum heat exchange (Wm-2K-1) at zero wind

1+CAN_RS_MULT = maximum factor to increase Cdata->rs below canopy

TRANSPIRATION Minimum canopy surface resistance, 500 (sm-1) is for needle leaf treas van den Hurk et al (2000) *75% Gustafsson et al (2003)

gd (Pa-1) parameter for canopy surface resistance response to vapour pressure:

0.0003 = trees (needle or broadleafs)
0=crops, grass, tundra etc

Root depth, determining the soil layers influenced by root water uptake

Wilting point, defined as a fraction of water content at field capacity (-)

Wilting point pressure head, when using Richards equation for soil.

< longwave emissivity (1)

< radiation transmissivity (1)

< from canopy air to reference height

< from canopy to canopy air

< from subsurface to canpopy air

< canopy albedo [-]

< total albedo above canopy and snow/soil surface [-]

< fraction of canopy covered by interception [-]

< maximum interception storage [mm]

< upward shortwave above canopy

< downward shortwave radiation above canopy

< upward shortwave below canopy

< downward shortwave radiation below canopy

< downward longwave radiation ABOVE canopy

< upward longwave radiation ABOVE canopy

< downward longwave radiation BELOW canopy

< upward longwave radiation BELOW canopy

< net shortwave radiation

< net longwave radiation

< snowfall above canopy

< rainfall above canopy

< radiation interception cross section for trunk layer ()

< biomass heat storage flux towards Canopy (if 1L) towards Leaves (if 2L). (>0 towards canopy)

< biomass heat storage flux towards Trunks (if 2L)

< net LW to trunks (>0 towards trunks)

< net SW to trunks (>0 towards trunks)

< sensible heat flux from trunks (>0 if heat lost from trunk)

< albedo of the forest floor

< basal area of trees on the stand

< Leaves heat mass (J K-1 /m2 ground surface)

< Trunks heat mass (J K-1 /m2 ground surface)

◆ initializeSurfaceExchangeData()

void CanopyData::initializeSurfaceExchangeData ( )

Function called to initialize the canopy "Surface" exchange data (to enable accumulated mass and energy fluxes)

◆ multiplyFluxes()

void CanopyData::multiplyFluxes ( const double & factor )

If multiple fluxes have been summed over multiple time steps, the fluxes then need to be averaged by the number of steps. The albedos are also averaged in this method.

Parameters

factor Averaging factor (for example, 1/Nsteps)

◆ reset()

void CanopyData::reset ( const bool & cumsum_mass )

◆ toString()

const std::string CanopyData::toString ( ) const

Friends And Related Function Documentation

◆ operator<<

std::ostream & operator<<	(	std::ostream &	os,
		const CanopyData &	data
	)

friend

◆ operator>>

std::istream & operator>>	(	std::istream &	is,
		CanopyData &	data
	)

friend

Member Data Documentation

◆ BasalArea

double CanopyData::BasalArea

basal area of trees on the stand

◆ biomass_density

double CanopyData::biomass_density

◆ biomass_heat_capacity

double CanopyData::biomass_heat_capacity

ENERGY BALANCE parameters for HeatMass and 2layercanopy

◆ can_alb_dry

double CanopyData::can_alb_dry

RADIATION BALANCE.

◆ can_alb_snow

double CanopyData::can_alb_snow

◆ can_alb_wet

double CanopyData::can_alb_wet

◆ can_ch0

double CanopyData::can_ch0

minimum heat exchange (Wm-2K-1) at zero wind

◆ can_diameter

double CanopyData::can_diameter

◆ can_rs_mult

double CanopyData::can_rs_mult

1+CAN_RS_MULT = maximum factor to increase Cdata->rs below canopy

◆ canopy_stabilitycorrection

bool CanopyData::canopy_stabilitycorrection

TURBULENT HEAT EXCHANGE Stab. corr. aerodyn. resist. above and below canopy: 0=off and 1=on (Monin-Obukhov formulation)

◆ canopyalb

double CanopyData::canopyalb

canopy albedo [-]

◆ canopytemp_maxchange_perhour

double CanopyData::canopytemp_maxchange_perhour

Maximum allowed canopy temperature change (K hr-1)

◆ CondFluxCanop

double CanopyData::CondFluxCanop

biomass heat storage flux towards Canopy (if 1L) towards Leaves (if 2L). (>0 towards canopy)

◆ CondFluxTrunks

double CanopyData::CondFluxTrunks

biomass heat storage flux towards Trunks (if 2L)

◆ direct_throughfall

double CanopyData::direct_throughfall

◆ displ_to_canopyheight_ratio

double CanopyData::displ_to_canopyheight_ratio

As above for displacement height.

◆ ec

double CanopyData::ec

longwave emissivity (1)

◆ et

double CanopyData::et

◆ f3_gd

double CanopyData::f3_gd

gd (Pa-1) parameter for canopy surface resistance response to vapour pressure:

0.0003 = trees (needle or broadleafs)
0=crops, grass, tundra etc

◆ forestfloor_alb

double CanopyData::forestfloor_alb

albedo of the forest floor

◆ h_wilt

double CanopyData::h_wilt

Wilting point pressure head, when using Richards equation for soil.

◆ height

double CanopyData::height

◆ HMLeaves

double CanopyData::HMLeaves

Leaves heat mass (J K-1 /m2 ground surface)

◆ HMTrunks

double CanopyData::HMTrunks

Trunks heat mass (J K-1 /m2 ground surface)

◆ ilwrac

double CanopyData::ilwrac

downward longwave radiation ABOVE canopy

◆ ilwrbc

double CanopyData::ilwrbc

downward longwave radiation BELOW canopy

◆ int_cap_rain

double CanopyData::int_cap_rain

Specific interception capacity for rain (I_LAI) (mm/LAI)

◆ int_cap_snow

double CanopyData::int_cap_snow

CANOPY PARAMETERS DEFAULT VALUES These values can be changed in the .sno file brief History of changed values:

2007-12-20: update based on data from all SnowMIP2 sites, and calibration using Alptal data brief Specific interception capacity for snow (i_LAI) (mm/LAI)
Please note that this parameter is further multiplied with (0.27+46/new_snow_density[Ta]) following (Pomeroy et al, Hydr. Proc. 1998)
5.9 Spruce and 6.6 Pine (Schmidt&Glums,CanJForRes,1991)

◆ intcapacity

double CanopyData::intcapacity

maximum interception storage [mm]

◆ interception

double CanopyData::interception

◆ interception_timecoef

double CanopyData::interception_timecoef

Coef in interception function, see (Pomeroy et al,1998) where a value of 0.7 was found to be appropriate for hourly time-step, but smaller time steps require smaller values, 0.5 was found reasoanble by using the SnowMIP2 data (2007-12-09)

◆ intevap

double CanopyData::intevap

◆ iswrac

double CanopyData::iswrac

downward shortwave radiation above canopy

◆ iswrbc

double CanopyData::iswrbc

downward shortwave radiation below canopy

◆ krnt_lai

double CanopyData::krnt_lai

◆ lai

double CanopyData::lai

◆ lai_frac_top_default

double CanopyData::lai_frac_top_default

◆ latent

double CanopyData::latent

◆ latentcorr

double CanopyData::latentcorr

◆ liquidfraction

double CanopyData::liquidfraction

◆ LWnet_Trunks

double CanopyData::LWnet_Trunks

net LW to trunks (>0 towards trunks)

◆ QStrunks

double CanopyData::QStrunks

sensible heat flux from trunks (>0 if heat lost from trunk)

◆ ra

double CanopyData::ra

from canopy air to reference height

◆ raincrease_snow

double CanopyData::raincrease_snow

Fractional increase of aerodynamic resistance for evaporation of intercepted snow.

10.0 from Koivusalo and Kokkonen (2002)
8.0 calibration with Alptal data

◆ rainfac

double CanopyData::rainfac

rainfall above canopy

◆ rc

double CanopyData::rc

from canopy to canopy air

◆ rlnet

double CanopyData::rlnet

net longwave radiation

◆ rlwrac

double CanopyData::rlwrac

upward longwave radiation ABOVE canopy

◆ rlwrbc

double CanopyData::rlwrbc

upward longwave radiation BELOW canopy

◆ rootdepth

double CanopyData::rootdepth

Root depth, determining the soil layers influenced by root water uptake.

◆ roughheat_to_roughmom_ratio

double CanopyData::roughheat_to_roughmom_ratio

(~=1, but Not allowed to be exactly 1)

◆ roughmom_to_canopyheight_ratio

double CanopyData::roughmom_to_canopyheight_ratio

Ratio between canopy height and roughness length.

◆ rs

double CanopyData::rs

from subsurface to canpopy air

◆ rsmin

double CanopyData::rsmin

TRANSPIRATION.

Minimum canopy surface resistance, 500 (sm-1) is for needle leaf treas van den Hurk et al (2000) *75% Gustafsson et al (2003)

◆ rsnet

double CanopyData::rsnet

net shortwave radiation

◆ rstransp

double CanopyData::rstransp

stomatal surface resistance for transpiration

◆ rswrac

double CanopyData::rswrac

upward shortwave above canopy

◆ rswrbc

double CanopyData::rswrbc

upward shortwave below canopy

◆ sensible

double CanopyData::sensible

◆ sigf

double CanopyData::sigf

radiation transmissivity (1)

◆ sigftrunk

double CanopyData::sigftrunk

radiation interception cross section for trunk layer ()

◆ snowfac

double CanopyData::snowfac

snowfall above canopy

◆ snowunload

double CanopyData::snowunload

◆ storage

double CanopyData::storage

intercepted water (mm or kg m-2)

◆ SWnet_Trunks

double CanopyData::SWnet_Trunks

net SW to trunks (>0 towards trunks)

◆ temp

double CanopyData::temp

temperature (K)

◆ throughfall

double CanopyData::throughfall

◆ totalalb

double CanopyData::totalalb

total albedo above canopy and snow/soil surface [-]

◆ transp

double CanopyData::transp

◆ trunk_frac_height

double CanopyData::trunk_frac_height

◆ trunkalb

double CanopyData::trunkalb

◆ Ttrunk

double CanopyData::Ttrunk

trunk temperature (K)

◆ wetfraction

double CanopyData::wetfraction

fraction of canopy covered by interception [-]

◆ wp_fraction

double CanopyData::wp_fraction