The app is based on the distribution of a global CO2 budget with a weighted key that takes into account a country's share of the world's population and of global emissions in the base year 2019. Thus, the distribution key reflects the current reality and climate justice.
In addition to national CO2 budgets, emission targets are shown based on linear emission paths.
These three central framework data can be specified in this web app:
The challenge is to find a combination that is compatible with the Paris climate targets (global CO2 budget), takes sufficient account of climate justice (weighting population), does not mean an uncovered check in the future in the case of net negative emissions and at the same time leads to realisable national targets, at least for the major emitters. As the results of the web app show, there is a trade-off between compliance with the Paris climate targets and climate justice. We must face up to this difficult issue. Based on an analysis of the figures, a realistic weighting of the population could be around 15%. On the fundamental question of a distribution key for a global budget, see the corresponding excursus in this paper.
Further sheets:
The cells marked in yellow are input fields. Guidance and background information for the tool here.
Please note: If you download this Excel tool as a copy, you can save entries for yourself. In addition, you can then print out the results for all countries or have a corresponding PDF created. We will be pleased to send you a non-read-only version on request (save-the-climate@online.ms).
Short version of this tool: http://short.national-budgets.climate-calculator.info.
EU version: http://eu.national-budgets.climate-calculator.info.
You can download a detailed Excel tool for calculating Paris-compatible CO2 budgets for all countries in the world: https://doi.org/10.5281/zenodo.5837866.
From an overall climate policy perspective, emission paths other than linear ones may make more sense. Therefore, we offer tools that cover the entire range of plausible emission paths:
We refer to the procedure of deriving a national CO2 budget from a global CO2 budget and deriving plausible national emission paths that adhere to the national CO2 budget as the Extended Smooth Pathway Model (ESPM). Here a brief description of the ESPM.