distribution of the ‘original’ CO2 budget (which, according to the IPCC, was about 3000 Gt CO2, as of 1750). On the other hand developed countries may argue, that even in relation to the final third of the pie, it is simply impractical to divide it equally. Levels of per capita GHG consumption in developed countries far exceed those in the developing world, an imbalance, which, in practical terms, can not suddenly be reversed. Both points have force (the former on the basis of equity; the latter on grounds of practicality). The following TEN STEP PROCESS is proposed as a practical framework for addressing both sets of concerns, ensuring that pragmatism does not come at the expense of equity (nor vice versa). Step 1: Assess the total carbon budget available from the start of the industrial age (say 1750) consistent with the 1.5 / 2 dc temperature goal: T (Gt CO2) Step 2: Determine the total global population from 1750 to projected decarbonisation date (say 2050): P Step 3: Define per capita shares of the total carbon budget as T/P tonnes of CO2: K (tonnes CO2) Step 4: Calculate the total population for each Party between 1750 and 2050: P1, P2 etc Step 5: Define equitable shares of the total carbon budget for each country as K x P1, K x P2 etc, tonnes of CO2: T1, T2 etc (Gt CO2) Step 6: Calculate total actual emissions for each country: M1, M2 etc (Gt CO2) Step 7: Calculate the difference between equitable and actual share for each country as T1-M1, T2-M2 etc: C1, C2 etc (Gt CO2) where the difference is positive (a GHG ‘credit’); D1, D2 etc (Gt CO2), where negative (a GHG ‘debit’). Step 8: Assess the future carbon budget consistent with a high degree of probability of meeting the temperature goal: F (Gt CO2). Step 9: Use the principles of contraction and convergence to determine practical country shares of this budget: F1, F2 etc Gt CO2. Step 10: Apportion liability for loss and damage, attributable to warming in excess of the temperature goal, on the basis of D / D1, D2 etc (where D is the sum of D1, D2, D3 etc). Breach of the duty to prevent might be established on one of two bases: 51