The Intergovernmental Panel on Climate Change’s (IPCC) recent Working Group III report on climate mitigation makes for sobering reading. Under current policy settings, the world is on track for global heating of 3.2 °C by 2100. If Canberrans are serious about doing our bit for the climate, we need to act fast.

Nonetheless, there are some positives. Chapter 8 of the report provides an array of evidence of the power of local policymakers to make deep cuts to our emissions by enabling more sustainable urban design. As ACT policymakers consider reforms to the ACT’s planning rules this year, here’s three findings from they need to keep in mind.

1. Urbanisation is an opportunity, not a threat

Some people see dense cities, along with their many busses, footpaths, and apartment buildings as anathema to climate action. However, as the latest IPCC report makes clear, while emissions from cities are increasing, continued urbanisation still represents an important opportunity to decrease emissions:

The growing concentration of people and activities is an opportunity to increase resource efficiency and decarbonize at scale…For most regions, per capita urban emissions are lower than per capita national emissions. (Chapter 8 Executive Summary)

Far from being a risk to the climate, urban growth can advance climate action by attracting new investment in low-carbon infrastructure, and enabling communities to reduce their combined carbon emissions. As the IPCC finds:

For the same level of consumption and basic services, an average urban dweller often requires less energy than their rural counterparts, due to higher population densities that enable sharing of infrastructure and services. (Chapter 8 Box 8.1)

Unfortunately, the fact that urban density can decrease carbon emissions is still yet to sink in among much of the public. ACT policymakers need to be clear about the state of the research, and bring the public along with them by highlighting the key role more compact cities can play in climate action.

2. Suburban sprawl is making climate damage worse

As the Chapter 8 of the report makes clear, the continued expansion of cities outwards, both in the developed and developing world, has serious impacts for both land use and urban heat:

Under the current urbanization trajectory, 50-63% of newly expanded urban areas are expected to occur on current croplands…Future urban expansion will amplify background warming caused by greenhouse gas emissions. (Chapter 8 Section 8.4.3)

That’s not all however - suburban sprawl also increases carbon emissions by increasing transport fuel use and requiring more emissions-intensive building materials to house the same number of people. That’s why the IPCC report argues that while there’s many ways to cut urban emissions, they all involve building up not out:

Low-carbon cities have the following characteristics: (1) co-located medium to high densities of housing, jobs, and commerce; (2) high mix of land uses; (3) high connectivity of streets; and (4) high levels of accessibility, distinguished by low travel distances…Modifying the layout of emerging urbanization to be more compact, walkable, and co-located can reduce future urban energy use by 20–25% by 2050. (Chapter 8 Section 8.4.2)

It’s a message that Canberra’s planners needs to take on board. Currently, many of our inner city suburbs are still subject to extensive planning rules - from minimum parking requirements to height restrictions - that make more compact infill neighbourhoods impossible. Ultimately, these planning rules force us to rely on greenfield development far from jobs and amenities to accomodate population growth. If we’re serious about climate action, that’s going to have to change.

3. Denser cities enable innovation, efficiency, and electrification

Finally, the IPCC report also makes clear why denser and more connected cities are an enabler for a range of other means of reducing emissions:

  • Putting homes near jobs and amenities reduces car use (which reduces emissions even if the car is electric!)
  • More compact cities make it cheaper and easier to install zero-emissions transport infrastructure, such as bike lanes and clean public transport
  • Denser homes enable more efficient heating and cooling systems, along with a more rapid roll-out of clean electric infrastructure
  • More connected cities create opportunities to innovate on the technologies that are key to reducing carbon emissions.

Canberra shares many of these goals, from increasing public transport usage, to electrifying households, to becoming a centre for clean innovation. Unfortunately, our planning system is working against us by limiting mixed-use developments and mid-density homes in central areas, and requiring all new homes to provide large amounts of off-street parking.

There’s no time to wait

If Canberra wants to meet our ambitious climate goal of net zero by 2045, we need to move fast. And that doesn’t just mean cleaner energy or less waste. It means changing our planning rules to enable a more sustainable city.

The research is clear. We need our local politicians to step up and act.