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FlexDamage

Flexible Damage Functions are statistical emulators of the high-resolution CIL projections, which can be incorporated into other models to project climate impacts and damages. These damage functions map global or national temperature and national income levels to impact levels. This is useful to estimate impacts along new socioeconomic and climate scenarios and for models for which income and/or temperature are endogenous.

The estimated damage function is:

\[D_{it} = (\alpha_i T_t + \beta_i T_t^2) \cdot Y_{it}^{\gamma}\]

where \(D_{it}\) is the impact for region \(i\) at time \(t\), \(T_t\) is the global mean temperature anomaly from pre-industrial, \(Y_{it}\) is GDP per capita, and \(\gamma\) is the income elasticity.

The full projection equation with uncertainty is:

\[D_{it}^k = (\hat{\alpha}_{ik} T_t + \hat{\beta}_{ik} T_t^2) Y_{it}^{\hat{\gamma}_k} + \hat{\theta}_{ik} T_t Y_{it}^{\hat{\gamma}_k} + \hat{\phi}_{it}^k\]

where \(k\) indexes the Monte Carlo draw, \(\hat{\gamma}_k\) is one of 19 quantile values, \(\hat{\alpha}_{ik}\) and \(\hat{\beta}_{ik}\) are drawn from the joint normal with the provided VCV (sigma11, sigma12, sigma22), \(\hat{\theta}_{ik}\) is drawn from \(N(0, \zeta_{ik})\) (the run-specific temperature-dependent error), and \(\hat{\phi}_{it}^k\) is drawn from \(N(0, \eta_{ik})\) (the annual noise). \(\rho_i\) controls the correlation between regional and global \(\theta\) draws.

For users

The links below describe how to use and interpret the Flexible Damage Function parameter files.

For developers

The links below describe FlexDamage, CIL's tool for creating Flexible Damage Functions.