Boundary Conditions of a Finite Planet for Planning a Carbon-negative City (pdf)
The City of Helsinki is aiming for carbon neutrality by 2030, carbon zero by 2040 and carbon negativity after that. As the carbon neutrality objective set for 2030 means that the City’s CO2 emissions must be decreased by 80% from the level of 1990 and the remaining 20% can be compensated for outside the city borders, the mere transition to carbon zero requires that the CO2 emissions produced and sequestered by the City are in balance within the city borders. In turn, carbon negativity means that emissions generated within the city borders must be lower than the City’s ability to sequester carbon through its own actions.
The aim of this report is to support the concretisation of a carbon-negative future by providing information regarding both changes to be expected in our immediate operating environment and the most critical boundary conditions set by them for the City’s planning operations and functions. Based on interviews and discussions with experts, the report examines seven boundary conditions to be taken into account in the planning of a carbon-negative city: the emissions reduction need, material
limitations, biodiversity loss, global warming, increasing precipitation, windiness, and rise in sea levels and water bodies.