module NumRu::GPhys::EP_Flux in ep_flux.

Testprogram

Test script path is 'test/test_ep_flux.rb' in expand dir of gphys.tar.gz.

Index

module NumRu::GPhys::EP_Flux
- Functions:
  - ep_full_sphere
    - calculate EP Flux with full set equations on spherical coordinate.
  - div_sphere
    - calculate divergence on spherical coordinate, Not only for EP Flux!
  - strm_rmean
    - calculate residual mass stream function in spherical coordinate (it might be good precision, but enough test has not done yet.)
  - scale_height
    - get the scale height.
  - scale_height=
    - set the scale height.
  - radius
    - get the radus of planet.
  - radius=
    - set the radus of planet.
  - rot_period
    - get the rotation period of planet.
  - rot_period=
    - set the rotation period of planet.
  - g_forces
    - get the gravitational acceleration in surface.
  - g_forces=
    - set the gravitational acceleration in surface.
  - p00
    - get the reference surface pressure.
  - p00=
    - set the reference surface pressure.
  - cp
    - get the the specific heat at constant pressure of the atmosphere.
  - cp=
    - set the the specific heat at constant pressure of the atmosphere.
  - gas_const
    - get the specific heat at constant pressure of the atmosphere.
  - gas_const=
    - set the specific heat at constant pressure of the atmosphere.
  - get_constants
    - get the module variables
  - set_constants
    - set the module variables
  - make_gphys
    - convert Axis to GPhys.
  - to_w_if_omega
    - convert to velocity if gp is pressure velocity.
  - to_z_if_pressure
    - convert to altitude if gp is pressure.
  - to_p_if_altitude
    - convert to pressure if gp is altitude.
  - to_theta_if_temperature
    - convert to potential temperature of temperature if flag is true.
  - to_rad_if_deg
    - convert to radian if gp is degrees.
  - eddy_products
    - calculate eddy flux respect to dimname.
  - remove_0_at_poles
    - set value if the cos(phi) is 0 at poles (phi is latitude).
  - preparate_for_vector_on_merdional_section
    - preparate for GGraph::vector_on_merdional_section in vector_on_merdional_section.rb
  - preparate_for_strm_rmean
    - preparate for strm_rmean
- Constants:
  - Deriv_methods
    - derivative method names.

module NumRu::GPhys::EP_Flux

Module functions of EP_Flux Operater for GPhys.

Functions:

ep_full_sphere(gp_u, gp_v, gp_w_or_omega, gp_temp_or_theta, flag_temp_or_theta, xyzdims=[0,1,2])

Calculate Eliassen-Palm Flux(EP-Flux) from full set equations on the spherical coordinate. this method calculates EP-Flux from 4 GPhys objects, zonal-wind velocity(U), merdional-wind velocity(V), vertical-wind velocity(W) or pressure velocity(Omega), and temperature(T) or potential(Theta) temperature. check the equations on documents.

Furthermore, Residual mean merdional circulation (0, v*, w*) can be calculated.

ARGUMENTS

gp_u (GPhys): a GPhys which data is U.
gp_v (GPhys): a GPhys which data is V.
gp_w_or_omega (GPhys): a GPhys which data is W or Omega. if you give gp_omega, convert to W in this method and calculate EP-Flux.
gp_temp_or_theta (GPhys): a GPhys which data is T or Theta.

xyzdims (Array): an Array which represents location of upper gphyses's

coordinate. if coordinate configuration is 
(longitude, latitude, z), then xyzdims = [0, 1, 2].
else if coordinate configuration is 
(z, latitude, longitude), then xyzdims = [2, 1, 0].

RETURN VALUE

epflx_y (GPhys): EP-Flux y-component. it is on the merdional hoge.
epflx_z (GPhys): EP-Flux z-component.
v_rmean (GPhys): residual zonal mean V.
w_rmean (GPhys): residual zonal mean W.
gp_lat (GPhys): latitude (its units is radian)
gp_z (GPhys): from vertical axis (z)
u_mean (GPhys): zonal-mean U.
theta_mean (GPhys): zonal-mean Theta.
uv_dash (GPhys): zonal mean of zonal-eddy products U and V.
vt_dash (GPhys): zonal mean of zonal-eddy products V and Theta.
uw_dash (GPhys): zonal mean of zonal-eddy products U and W.
dtheta_dz (GPhys): zonal mean Theta derivate with z.

div_sphere(gp_y, gp_z)

Calculate divergence on the spherical coordinate. it is exclusive to in merdional cross section.

ARGUMENTS

gp_y (GPhys): a GPhys which is merdional component you want to calculate
```
divergence.
```
gp_z (GPhys): a GPhys which is vertical component you want to calculate
```
divergence.
```

RETURN VALUE

gp_div (GPhys): a GPhys which is divergence on the spherical coordinate.

set_deriv_method( method_name )

Set derivative method. methods are defined in GPhys::derivative. Now cderiv and threepoint_O2nd_deriv supported

ARGUMENTS

method_name (String): derivative method name.

RETURN VALUE

deriv( *args )

Call derivative method defined in GPhys::Derivative refer to @@deriv_method.

ARGUMENTS

args : Option for derivative method. Pleaase see GPhys::Derivative.

RETURN VALUE

scale_height

return a value of the scale height on the log-pressure coordinate. default value is "7000 m".

RETURN VALUE
* scale height (UNumeric)

scale_height=(h)

set a value of the scale height on the log-pressure coordinate.

RETURN VALUE
* nil

radius

return a value of the radius of the planet. default value is "6.37E6 m".

RETURN VALUE
* radius (UNumeric)

radius=(a)

set a value of the radius of the planet.

RETURN VALUE
* nil

rot_period

return a value of the rotation period of the planet. default value is "8.64E4 s".

RETURN VALUE
* rotation period (UNumeric)

rot_period=(rp)

set a value of the rotation period of the planet.

RETURN VALUE
* nil

g_forces

return a value of the gravitational acceleration on the surface. default value is "9.81 m/s2".

RETURN VALUE
* rotation period (UNumeric)

g_forces=(g)

set a value of the gravitational acceleration on the surface.

RETURN VALUE
* nil

p00

return a value of the reference surface pressure. default value is "1.0E5 Pa".

RETURN VALUE
* reference surface pressure (UNumeric)

p00=(p00)

set a value of the reference surface pressure.

RETURN VALUE
* nil

cp

return a value of the specific heat at constant pressure of the atmosphere. default value is "1004.0[J.K-1.kg-1]"

RETURN VALUE
* reference surface pressure (UNumeric)

cp=(cp)

set a value of the specific heat at constant pressure of the atmosphere.

RETURN VALUE
* nil

gas_const

return a value of the gas constant divided by molecular mass. default value is "287.0[J.K-1.kg-1]".

RETURN VALUE
* reference surface pressure (UNumeric)

gas_const=(r)

set a value of the gas constant divided by molecular mass.

RETURN VALUE
* nil

get_constants

return values of the scale height, radius, rotation period, gravitational acceleration, reference surface pressure, specific heat, gas constant.

RETURN VALUE
* scale height (UNumeric)
* radius (UNumeric)
* rotation period (UNumeric)
* gravitational acceleration (UNumeric)
* reference surface pressure (UNumeric)
* specific heat at constant pressure of the atmosphere (UNumeric)
* gas constant divided by molecular mass (UNumeric)

set_constants(scale_height, radius, rot_period, g_forces, p00, cp, gas_const)

set values of the scale height, radius, rotation period, and gravitational acceleration.

ARGUMENTS
* scale height (UNumeric)
* radius (UNumeric)
* rotation period (UNumeric)
* gravitational acceleration (UNumeric)
* reference surface pressure (UNumeric)
* specific heat at constant pressure of the atmosphere (UNumeric)
* gas constant divided by molecular mass (UNumeric)

RETURN VALUE
* nil

make_gphys(*ax_ary)

make GPhys objects from Axis or VArray. data components is VArray of Axis.pos.

ARGUMENTS

ax_ary (Array): an Array each objects are Axis or VArray.

RETURN VALUE

gp_ary (Array): an Array each objects are GPhys.

to_w_if_omega(gp, z)

convert to velocity(W) if gp is pressure velocity(Omega). decide from units gp.data.units. if it compatible with "m/s" then deem it W, else if "Pa/s" then deem it Omega.

ARGUMENTS

gp(GPhys): a GPhys which data represents velocity or pressure velocity.
z(GPhys): a GPhys which data represents z-coordinate.

RETURN VALUE

gp_w(GPhys): a GPhys which data represents velocity or pressure velocity

to_z_if_pressure(gp)

convert to altitude(z) if gp is pressure coordinate (p). decide from units gp.data.units. if it compatible with "Pa" then deem it (p).

ARGUMENTS

gp(GPhys): a GPhys which data represents z or pressure coordinate.

RETURN VALUE

gp_z(GPhys): a GPhys which data represents z-coordinate.

to_p_if_altitude(gp)

convert to pressure(p) if gp is altitude(z). decide from units gp.data.units. if it compatible with "m" then deem it (z).

ARGUMENTS

gp(GPhys): a GPhys which data represents z or pressure coordinate.

RETURN VALUE

gp_p(GPhys): a GPhys which data represents p-coordinate.

to_theta_if_temperature(gp_t, z, flag_temp_or_theta=true)

convert gp to potential temperature(\theta) if flag_temp_or_theta is true.

ARGUMENTS

gp_t(GPhys): a GPhys which data represents potential temperature or
```
temperature.
```
z(GPhys) : a GPhys which data represents z-coordinate.
flag_temp_or_theta(True or False): a flagment if gp_t convert to.

RETURN VALUE

gp_theta(GPhys): a GPhys which data represents potential temperature.

to_rad_if_deg(gp)

convert to radian if gp.data.units is degrees.

ARGUMENTS

gp(GPhys): a GPhys which represents angle (radian or degree).

RETURN VALUE

gp_rad(GPhys): a GPhys which units is radian.

eddy_products(gp_u, gp_v, gp_w, gp_t, dimname)

calculate eddy products along "dimname" dimension. now in this documents, ' means eddy from zonal mean, and () means zonal mean.

ARGUMENTS

gp_u(GPhys): a GPhys which data represents zonal-wind velocity(m/s).
gp_v(GPhys): a GPhys which data represents merdional-wind velocity(m/s).
gp_w(GPhys): a GPhys which data represents vertical-wind velocity(m/s).
gp_t(GPhys): a GPhys which data represents temperature(K).

RETURN VALUE

uv_dash(GPhys): a GPhys which represents (gp_u'*gp_v').
vt_dash(GPhys): a GPhys which represents (gp_v'*gp_t').
uw_dash(GPhys): a GPhys which represents (gp_u'*gp_w').

remove_0_at_poles(cos_gp)

set value if the cos(latitude) is nearly equal to 0 (|x|< 1e-6) at poles. at North pole, new value is 2 and at South pole 2

ARGUMENTS
* cos_gp(GPhys): a GPhys which represents latitude.

RETURN VALUE
* new_cos_gp(GPhys): a GPhys which value at poles displaceed.

preparate_for_vector_on_merdional_section(xax, yax)

preparate for GGraph::vector_on_merdional_section in vector_on_merdional_section.

check yax if it is proportional to p
get axis ( a*phi, z )

ARGUMENTS
* xax(VArray): a VArray which represents x axis.
* yax(VArray): a VArray which represents y axis.

RETURN VALUE
* va_aphi(VArray): a VArray which represents x-coordinate(radius * phi).
* va_z(VArray): a VArray which represents z-coordinate.
* was_proportional_to_p(True or False): flag original axis proportional to 
                                        pressure or z.

preparate_for_divergence_on_merdional_section(xax, yax)

preparate for divergence_on_merdional_section.

check yax if it is proportional to p
get axis ( a*sin(phi), z , cos(phi))

ARGUMENTS
* xax(VArray): a VArray which represents x axis.
* yax(VArray): a VArray which represents y axis.

RETURN VALUE
* va_a_sin_phi(VArray): a VArray which represents x-coordinate(radius * sin(phi)).
* va_z(VArray): a VArray which represents z-coordinate.
* va_cos_phi(VArray): a VArray which represents x-coordinate(radius * cos(phi)).
* was_proportional_to_p(True or False): flag original axis proportional to 
                                        pressure or z.

strm_rmean(v_rmean, yzdims=[0,1])

!! CAUTION !! Now this method might show good precision, but we have not enough test and debuged yet. So, there is no gurantee. please use with your responsibility.

Calculate mass stream function for residual zonal mean circulation. Residual zonal mean circulation defined of this module is nondivergent if products a value like a reference density profile (sigma), thus one can define mass stream function Psi.

ARGUMENTS

v_rmean (GPhys): a GPhys which is residual zonal mean V.
yzdims (Array): an Array which represents axis.

RETURN VALUE

gp_strm (GPhys): a GPhys which is mass stream function on merdional section.

preparate_for_strm_rmean(gp_data, gp_p, z_dim)

preparate for strm_rmean. its works

expand 2 grid in the top boundary of pressure coordinate.
interpolation with linear extention.
top boundary condition is "p = 0".

ARGUMENTS
* gp_data (GPhys): a GPhys which you wants to expand to.
* gp_p    (GPhys): a GPhys which represents axis you wants expand to.
* z_dim   (Numric): a Numeric which represents dimension of pressure.

RETURN VALUE
* ext_gp_data (GPhys): a GPhys which extend top boundary.

Constants:

Deriv_methods: derivative method name [ 'cderiv', 'threepoint_O2nd_deriv' ]