Rabbits stick to their Carbon Budgets

Take the Jump

• The City of Melbourne is part of a grouping of 100 cities from around the world (C40 Cities Climate Leadership Group) which have committed to reducing GHG emissions consistent with a 1.5degC World (67% confidence) [1].
• Emission targets have been informed by a report titled The Future of Urban Consumption in a 1.5°C World [2]
• The report models the effects of several interventions to reduce GHG emissions:
  • Reducing the number of new clothing items bought each year
  • A shift to a plant based diet
  • Keep electrical products for 7 years
  • No personal cars for travel
  • Holiday local or travel short haul once every 3 years
  • Advocate for systemic change

C40 Cities and Climate Change Pledges

• C40 Cities (which include Melbourne and Sydney) have set the following targets
  • 50% reduction in emissions by 2030
  • net zero emissions by 2050

Climate math: What a 1.5-degree pathway would take

• These targets are based on good science [3].
  • A 50-55% reduction on CO2 emissions by 2030 based on 2010 levels
  • Staying within a 570 GtCO2 cumulative carbon budget. Budget of 570 GtCO2 emissions from 2018 onward offers a 66% chance of limiting global warming to 1.5°C, when assessing historical temperature increases from a blend of air and sea-surface temperatures.

Limitations

• There limitations associated with these targets.
  • During the period of steep mitigation of non-CO2 greenhouse gases are not addressed
  • The achievement of net zero emissions to 2050 relies on reforestation and carbon-removal technologies such as bioenergy with carbon capture and storage (BECCS) and direct air carbon capture and storage (DACCS) - so-called Negative emissions. Some of these technologies are in their infancy and unproven at the scale required in the model.