Carbon budgets

Today, not tomorrow… what carbon budgets show us

A carbon budget sets a limit to the amount of carbon we can emit or ‘spend’ to maintain a healthy and sustainable climate balance on Planet Earth. Rather than looking at carbon emissions at a point in time, it uses a cumulative total of emissions over a period. This is a more robust way of measuring our progress on reducing carbon emissions to have an impact on climate change.

Globally we are all overspending right now. We are on track for an ‘unauthorised overdraft’, and we’ve ignored the warning letters from the bank.  In this case the bank is planet earth, and the warnings have been changes in weather patterns across the globe with sometimes catastrophic impacts.  Continued carbon spending will lead to an escalating impact on global weather systems. Beyond a certain point, this will affect a broad range of fundamental aspects of our human existence, including for example sufficient food and water and the need for many to migrate to find it.

Recommendations from the IPCC

The Intergovernmental Panel on Climate Change (IPCC) has recommended that to prevent runaway climate change we need to keep the rise in the average global surface temperature to 1.5 to 2°C above pre-industrial levels.  The IPCC has also estimated the amount of carbon dioxide and other greenhouse gases we have left to emit before we reach that temperature rise – a global carbon budget.

There’s a beautiful simplicity in a carbon budget. We know how much we have left to spend and we know how fast we are spending it.  We can then plan our spending to make sure we stay within budget.  The faster we spend it the quicker our planet warms. 

A sobering realisation

The Tyndall Centre for Climate Change has used a global carbon budget from the IPCC to derive a fair carbon budget for every local authority within the UK.  The UK government measures and publishes national and local authority CO2 emissions data annually. Therefore every local authority can see what their carbon budget is and see how quickly they are currently “spending” carbon.  This tells us is that most local authorities will have used all their carbon budget by 2027, at current rates of emissions.

We have no time to wait before we reduce our carbon emissions – but they are still rising!  

Calculations show that in the UK we need to be practically zero carbon by the early 2030s if we are to stay within our Paris compliant carbon budget , with steep reductions between now and then. 

Many net zero plans have a target date – e.g. 2030 or 2040 or in the case of UK’s emissions 2050.  But unless these are backed by a Paris compliant carbon budget approach to carbon spending they are meaningless. What’s important is how much carbon we spend, not an arbitrary date at which we stop spending it.  Without this there’s a risk that target dates may be painfully insufficient. 

Danger in buying carbon-offsetting

Unfortunately tree planting and other forms of common carbon offsets are not going to reduce the amount of carbon we need in the time required.  Similarly additional renewable energy generated will not negate burning gas and oil.  If carbon offsets are used by organisations instead of potential real carbon reductions then they get in the way of reducing real emissions. This sort of carbon accounting must be accompanied by robust and ambitious decarbonisation plans that rapidly transition away from burning fossil fuels.

We need to do what we can, now, to stop burning fossil fuels

No doubt there’s a huge challenge ahead.  But we can choose to see this as an exciting time of collective purpose, creativity and innovation.  And I have a sneaky feeling we will get to enjoy some positive spin-offs in the process.