Climate Data

About the City Carbon Budget API

The City Carbon Budget API returns an individual municipality’s total Carbon Budget as well as 4 different emissions abatement trajectories to show the Carbon Budget’s expenditure over time.

It currently provides Carbon Budgets for the 290 municipalities in Sweden.

Simplifying city-level attribution

The global Carbon Budget of how much more carbon we can emit is calculable, and several Carbon Budgets have been suggested by the IPPC as mechanisms for limiting global temperature rise. However, calculating how much of this budget should be allocated to each nation, and then further divided within each nation to a regional or cities level, is a more complex process.

To attribute the Carbon Budget to the municipality-level, ClimateView has built on the work of the Tyndall Centre to create a programmable and repeatable calculation approach.

About the data

The ClimateView Climate Data API delivers two types of climate data:

  • historic emission data according to SMHI
  • carbon budgets for Sweden’s 290 kommuns (with a number of proposed scenarios for reducing emissions).

CC BY NC SA - Open and Free

The API is open and free for use under a CC BY NC SA - Attribution-NonCommercial-ShareAlike 4.0 International license.

Our goal with this project is to increase the use of Carbon Budgets and improve the transparency of their calculation, to empower science-based conversations about the progress of the climate transition.

Historic Emissions


The overview of historic emissions are found at the endpoint:

This gives the national emissions of every municipality (kommun) in Sweden. The emissions are given for each municipality as a total and divided into main sectors.


The historic emissions for a specific municipality can be found at{name} where name is the name of the municipality exactly as given by the overview of municipality emissions.

The emissions per municipality is given as a total and divided into main sectors and sub-sectors.

CO2 Budgets

Budget Scenarios

Each municipality has been allocated a CO2 budget.

The budget for a specific municipality is found at:{name} where name is the name of the municipality exactly as given by the overview of municipality emissions.
E.g. With each budget comes four scenarios for how the municipality could spend this budget. Key figures about the budget are given for each scenario (e.g. when zero emissions is reached, how much CO2 will be spent etc.). A series of yearly emissions (starting at the first year of the budget) are also given to indicate the CO2 emissions each year of consuming the remaining budget.

The scenarios are:

  • Linear Emission Reduction Scenario. The budget is spent using a linear cut-down from current emissions level, reducing the amount of emitted CO2 by the same absolute amount each year. This linear cut-down reaches zero emission at the same moment in time that the budget is spent.
  • Exponential Emission Reduction Scenario. The budget is spent using a cut-down of emissions, from the current emission level, by the same percent each year . The actual yearly cut-down in percentage needed to stay within budget can be calculated (a mathematical integral). However, as exponential cut-down will not ever reach zero emissions, a cut off level is used, so that the series of yearly emission becomes finite. The cut off is given as a fraction of the last known historic emission and is part of the data returned from the API. Currently a fraction of 0.01 is used.
  • Trend Based Emissions Scenario Limited by Budget. The budget is spent according to the trend of the historic emissions. The series of yearly emissions are ended when the budget is spent or when zero emissions are reached (whichever happens first). For a municipality where the trend is not to clearly cut down on emissions, this would mean the series of yearly emissions would end abruptly without being anywhere near zero emissions.
  • Trend Based Emissions Scenario Limited by Zero Emissions or End Year. This series of yearly emission is showing the future trend of the municipality regardless of budget. The series of emissions will end at a given end year (currently 2050) if zero emissions are not reached by then.

Budget Data Examples

Apart from the series of yearly emissions, other data is available for each municipality and its scenarios. This data give additional knowledge about the trends of historic emissions relative to the allocated budget. The exact details of these properties are given by the Open API documentation for the API. These are examples to give an understanding of what you can find out about the different scenarios:

The percentage of the national budget this municipality has been allocated

The total CO2 budget this municipality has been allocated

The date of reaching zero emissions or the date when the budget is consumed, whichever happens first

The date of reaching zero emissions. Will not be present if the municipality will never reach zero emissions, e.g emissions in trend are increasing year by year

Set for exponential emission reduction only as this is a fixed figure only for exponential reduction

Set for exponential emission reduction only. As exponential emission reduction never reach zero emissions, we need to assume we end the series of yearly emissions when emissions are down to a certain fraction of the current emissions. Currently 0.01 is used.

Sum of all emissions in the series of emissions of the years in the emission reduction

Sum of all emissions until zero emissions are reached. Only set if emissions decreasing according to trend

OpenAPI Spec

OpenAPI Specification for the Climate Data API.