landlab.components.radiation.radiation

class Radiation[source]

Bases: Component

Compute 1D and 2D daily incident shortwave radiation.

Landlab component that computes 1D and 2D daily extraterrestiral, clear-sky, incident shortwave, net shortwave, longwave, and net radiation. This code also computes relative incidence shortwave radiation compared to a flat surface calculated at noon.

References

Bras, R. L.: Hydrology: an introduction to hydrologic science, Addison Wesley Publishing Company, Boston, Mass., USA, 643 pp., 1990.

ASCE-EWRI (2005) The ASCE standardized reference evapotranspiration equation. In: Allen RG, Walter IA, Elliot RL et al (eds) Environmental and Water Resources Institute (EWRI) of the American Society of Civil Engineers, ASCE, Standardization of Reference Evapotranspiration Task Committee final report. American Society of Civil Engineers (ASCE), Reston

Allen, R.G., 1996. Assessing integrity of weather data for reference evapotranspiration estimation. J. Irrig. Drain. Eng., ASCE 122 (2), 97-106.

Flores-Cervantes, J.H., E. Istanbulluoglu, E.R. Vivoni, and R.L. Bras (2014). A geomorphic perspective on terrain-modulate organization of vegetation productivity: Analysis in two semiarid grassland ecosystems in Southwestern United States. Ecohydrol., 7: 242-257. doi: 10.1002/eco.1333.

Code author: Sai Nudurupati & Erkan Istanbulluoglu & Berkan Mertan

Examples

>>> from landlab import RasterModelGrid
>>> from landlab.components import Radiation
>>> import numpy as np

>>> grid = RasterModelGrid((5, 4), xy_spacing=(0.2, 0.2))
>>> z = grid.add_zeros("node", "topographic__elevation")
>>> rad = Radiation(grid)

>>> grid.at_node["topographic__elevation"] = [
...     [0.0, 0.0, 0.0, 0.0],
...     [1.0, 1.0, 1.0, 1.0],
...     [2.0, 2.0, 2.0, 2.0],
...     [3.0, 4.0, 4.0, 3.0],
...     [4.0, 4.0, 4.0, 4.0],
... ]
>>> rad.current_time = 0.5
>>> rad.update()

>>> grid.at_cell["radiation__net_shortwave_flux"].reshape((3, 2))
array([[251.63813643, 251.63813643],
       [251.62345462, 251.62345462],
       [251.59409258, 251.59409258]])
>>> grid.at_node["topographic__elevation"] = [
...     [0.0, 0.0, 0.0, 0.0],
...     [100.0, 100.0, 100.0, 100.0],
...     [200.0, 200.0, 200.0, 200.0],
...     [300.0, 400.0, 400.0, 300.0],
...     [400.0, 400.0, 400.0, 400.0],
... ]
>>> calc_rad = Radiation(grid, current_time=0.0, kt=0.2)
>>> calc_rad.update()

>>> grid.at_cell["radiation__net_shortwave_flux"].reshape((3, 2))
array([[188.10745478, 188.10745478],
       [187.84329564, 187.69076199],
       [183.82445291, 183.41439585]])

References

Required Software Citation(s) Specific to this Component

None Listed

Parameters:

  • grid (RasterModelGrid) – A grid.

  • method ({'Grid'}, optional) – Currently, only default is available.

  • cloudiness (float, optional) – Cloudiness.

  • latitude (float, optional) – Latitude (radians).

  • albedo (float, optional) – Albedo.

  • kt (float, optional) – Regional coefficient applied to actual KT coefficient (0.15-0.2). Default is 0.15

  • clearsky_turbidity (float, optional) – Clear sky turbidity.

  • opt_airmass (float, optional) – Optical air mass.

  • max_daily_temp (float, optional) – Maximum daily temperature (Celsius)

  • min_daily_Temp (float, optional) – Minimum daily temperature (Celsius)

  • current_time (float) – Current time (years).

__init__(grid, method='Grid', cloudiness=0.2, latitude=34.0, albedo=0.2, kt=0.17, clearsky_turbidity=None, opt_airmass=None, current_time=0.0, max_daily_temp=25.0, min_daily_temp=10.0)[source]
Parameters:

  • grid (RasterModelGrid) – A grid.

  • method ({'Grid'}, optional) – Currently, only default is available.

  • cloudiness (float, optional) – Cloudiness.

  • latitude (float, optional) – Latitude (radians).

  • albedo (float, optional) – Albedo.

  • kt (float, optional) – Regional coefficient applied to actual KT coefficient (0.15-0.2). Default is 0.15

  • clearsky_turbidity (float, optional) – Clear sky turbidity.

  • opt_airmass (float, optional) – Optical air mass.

  • max_daily_temp (float, optional) – Maximum daily temperature (Celsius)

  • min_daily_Temp (float, optional) – Minimum daily temperature (Celsius)

  • current_time (float) – Current time (years).

static __new__(cls, *args, **kwds)
property actual_vapor_pressure
cite_as = ''
property coords

Return the coordinates of nodes on grid attached to the component.

property current_time

Current time.

Some components may keep track of the current time. In this case, the current_time attribute is incremented. Otherwise it is set to None.

Return type:

current_time

property day_of_year
definitions = (('radiation__clearsky_flux', 'clearsky radiation'), ('radiation__extraterrestrial_flux', 'extraterrestrial radiation'), ('radiation__incoming_shortwave_flux', 'incident shortwave radiation'), ('radiation__net_flux', 'net radiation'), ('radiation__net_longwave_flux', 'net incident longwave radiation'), ('radiation__net_shortwave_flux', 'net incident shortwave radiation'), ('radiation__ratio_to_flat_surface', 'ratio of incident shortwave radiation on sloped surface to flat surface'), ('topographic__elevation', 'Land surface topographic elevation'))
classmethod from_path(grid, path)

Create a component from an input file.

Parameters:

  • grid (ModelGrid) – A landlab grid.

  • path (str or file_like) – Path to a parameter file, contents of a parameter file, or a file-like object.

Returns:

A newly-created component.

Return type:

Component

property grid

Return the grid attached to the component.

initialize_optional_output_fields()

Create fields for a component based on its optional field outputs, if declared in _optional_var_names.

This method will create new fields (without overwrite) for any fields output by the component as optional. New fields are initialized to zero. New fields are created as arrays of floats, unless the component also contains the specifying property _var_type.

initialize_output_fields(values_per_element=None)

Create fields for a component based on its input and output var names.

This method will create new fields (without overwrite) for any fields output by, but not supplied to, the component. New fields are initialized to zero. Ignores optional fields. New fields are created as arrays of floats, unless the component specifies the variable type.

Parameters:

values_per_element (int (optional)) – On occasion, it is necessary to create a field that is of size (n_grid_elements, values_per_element) instead of the default size (n_grid_elements,). Use this keyword argument to acomplish this task.

input_var_names = ('topographic__elevation',)
name = 'Radiation'
optional_var_names = ()
output_var_names = ('radiation__clearsky_flux', 'radiation__extraterrestrial_flux', 'radiation__incoming_shortwave_flux', 'radiation__net_flux', 'radiation__net_longwave_flux', 'radiation__net_shortwave_flux', 'radiation__ratio_to_flat_surface')
property relative_distance_factor
run_one_step(dt=None)[source]
property shape

Return the grid shape attached to the component, if defined.

property solar_declination
unit_agnostic = False
units = (('radiation__clearsky_flux', 'W/m^2'), ('radiation__extraterrestrial_flux', 'W/m^2'), ('radiation__incoming_shortwave_flux', 'W/m^2'), ('radiation__net_flux', 'W/m^2'), ('radiation__net_longwave_flux', 'W/m^2'), ('radiation__net_shortwave_flux', 'W/m^2'), ('radiation__ratio_to_flat_surface', 'None'), ('topographic__elevation', 'm'))
update()[source]

Update fields with current loading conditions.

This method looks to the properties current_time and hour and uses their values in updating fields.

classmethod var_definition(name)

Get a description of a particular field.

Parameters:

name (str) – A field name.

Returns:

A description of each field.

Return type:

tuple of (name, *description*)

classmethod var_help(name)

Print a help message for a particular field.

Parameters:

name (str) – A field name.

classmethod var_loc(name)

Location where a particular variable is defined.

Parameters:

name (str) – A field name.

Returns:

The location (‘node’, ‘link’, etc.) where a variable is defined.

Return type:

str

var_mapping = (('radiation__clearsky_flux', 'cell'), ('radiation__extraterrestrial_flux', 'cell'), ('radiation__incoming_shortwave_flux', 'cell'), ('radiation__net_flux', 'cell'), ('radiation__net_longwave_flux', 'cell'), ('radiation__net_shortwave_flux', 'cell'), ('radiation__ratio_to_flat_surface', 'cell'), ('topographic__elevation', 'node'))
classmethod var_type(name)

Returns the dtype of a field (float, int, bool, str…).

Parameters:

name (str) – A field name.

Returns:

The dtype of the field.

Return type:

dtype

classmethod var_units(name)

Get the units of a particular field.

Parameters:

name (str) – A field name.

Returns:

Units for the given field.

Return type:

str