climate_metrics.GWP#
- climate_metrics.GWP(time_horizon, emissions, GHG, step_size=1, annual=False)#
Computes the CO2 equivalent radiative forcing of emissions.
Can be used to compute GWP over time_horizon of a single pulse emission, or a flow of emissions over time.
- Parameters
- time_horizonint
- emissionsint or ndarray
If emissions is an int, the emission is assumed to occur at time=0.
- GHGstr {‘CO2’, ‘CH4’, ‘N2O’}, optional
Type of GHG emission in emissions.
- step_sizefloat or int
Step size of emissions in years.
- annualbool
If True, returns annual GWP over the time_horizon. If False, returns the single value at time_horizon.
Notes
If step_size < 1, the sum of the net_emissions vector must be equal to total emissions. So if a probability density function were used to simulate net_emissions over time, net_emissions would first have to be weighted by step_size before being passed to this function.
Global Warming Potential is defined as the cumulative radiative forcing of \(GHG_x\) emitted in year = 0 over a given time-horizon (\(t\)):
\[GWP(t) = \frac{cumulativeRadiativeForcingGHG_x(t)} {cumulativeRadiativeForcingCO_2(t)}\]Dynamic GWP (variously referred to in the literature as tonne-year ([1], [2], [3]), GWP ([4]), and GWP_bio ([5])) computes the cumulative radiative forcing of annual (\(t'\)) emissions (\(GHG_x\)) over a give time-horizon (\(t\)):
\[\begin{split}\begin{eqnarray} dynamicGWP_x(t, t') & = & {\mathbf{emission_x}(t')}\cdot{\mathbf{GWP_x}(t-t')} \\ & = & \sum_{t'}{\mathbf{emission_x}(t') * {\mathbf{GWP_x}(t-t')}} \\ & = & \frac{\sum_{t'}{cumulativeRadiativeForcingGHG_x(t-t')}} {cumulativeRadiativeForcing_{CO2}(t)} \end{eqnarray}\end{split}\]References
- 1
IPCC, 2000. https://archive.ipcc.ch/ipccreports/sres/land_use/index.php?idp=74 # noqa: E501
- 2
Fearnside et al. 2000. https://link.springer.com/article/10.1023/A:1009625122628 # noqa: E501
- 3
Moura Costa et al. 2000. https://link.springer.com/article/10.1023/A:1009697625521 # noqa: E501
- 4
Levasseur et al. 2010. https://pubs.acs.org/doi/10.1021/es9030003
- 5
Cherubini et al. 2011. https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1757-1707.2011.01102.x # noqa: E501