DailyInsolationParam: Computes daily average insolation as a function of day and...

In EarthSystemDiagnostics/orbitalforcing: Orbital Forcing from Insolation

Computes daily average insolation as a function of day and latitude given the orbital parameters

Description

Insolation calculation, converted and adapted from the Eisenmann and Huybers,2006 Matlab Code, based on Berger 1991

Usage

DailyInsolationParam(
  lat,
  day,
  ecc,
  obliquity,
  long_perh,
  day_type = 1,
  alpha = 0,
  T.alpha = 80
)

Arguments

lat	Latitude in degrees (-90 to 90).
day	Indicator of time of year; calendar day by default.
ecc	eccentricity
obliquity	obliquity
long_perh	longitude of perihelion
day_type	Convention for specifying time of year (+/- 1,2) [optional], see details
alpha	parameter for custom calendar,see details
T.alpha	parameter for custom calendar,see details

Value

list(Fsw=Fsw, ecc=ecc, obliquity=obliquity, long_perh=long_perh, lambda=lambda/2/pi*360) Fsw = Daily average solar radiation in W/m^2. ... and all orbital parameters

day type details

day_type=1 (default): day input is calendar day (1-365.24), where day 1 is January first. The calendar is referenced to the vernal equinox which always occurs at day 80.

day_type=2: day input is solar longitude (0-360 degrees). Solar longitude is the angle of the Earth's orbit measured from spring equinox (21 March). Note that calendar days and solar longitude are not linearly related because, by Kepler's Second Law, Earth's angular velocity varies according to its distance from the sun.

day_type=3: Custom calendar that alpha (angle since equinox) is reached at day T.alpha this uses an iterative solution of Keplers equation and is therefore much slower than the day_type=1 which uses a trigeometric approximation of Kepler's equation.

Author(s)

Thomas Laepple

EarthSystemDiagnostics/orbitalforcing documentation built on March 24, 2022, 11:25 a.m.