What is Net Zero and why does it matter?

Net Zero policy has been a point of debate in the current Conservative party leadership contest.  There is a strand of opinion that sees Net Zero as costly and damaging to Britain.  This flies in the face of the evidence and international consensus.  But where does the concept of Net Zero come from and does it really matter? 

Net Zero is first and foremost a scientific concept, not a political one.  Net zero greenhouse gas emissions simply means that emissions into the atmosphere are balanced by processes removing them.  These ‘removals’ include natural processes, such as tree growth as well as technological approaches which are being developed.  Greenhouse gas concentrations in the atmosphere stop rising when Net Zero is reached and the climate can stabilise. 

The evidence is unequivocal that climate change is already affecting people and nature and that these impacts will increase with further global warming (Reflections on the Latest IPCC reports – The John Ray Initiative (jri.org.uk)).  This is a very real threat to the lives and livelihoods of billions of people.  Low-lying countries are already losing land to the sea; wildfires, droughts and floods are becoming more severe and more common. And we are experiencing more heatwaves as evidenced by the recent excessive temperatures over much of western Europe.  If Net Zero is not achieved, global temperature and the consequent impacts will simply go on increasing. 

In the Paris Agreement, the nations of the world agreed to hold global temperature rise to ‘well below 2°C and pursue efforts to limit it to 1.5°C’.  For this to happen global Net Zero needs to be reached as quickly as possible.  The longer it takes, the more greenhouse gases build up in the atmosphere and the higher temperature will rise before stabilising.  The Paris Agreement is a legally binding treaty under the UN Framework Convention on Climate Change.  The UK along with other countries has committed to play our part and we have staged targets in domestic law under the Climate Change Act to reach net zero as a nation by 2050 – with a 68% reduction in greenhouse gas emissions by 2030.  For these reasons, as well as the increasing widely recognised impacts of climate change, it would be deeply damaging for any British government to drop a commitment to meeting Net Zero, but also quite unlikely.  A more likely scenario is a delay in implementing the measures necessary to achieve Net Zero or a watering down of them, which would make it much harder to reach the objective.

At the present time, reducing the cost of living and helping the poorest in our society to make ends meet is clearly a moral as well as political imperative.  One of the most frequently cited reasons for delaying action on Net Zero is that it might push up bills for already hard-pressed families.  However, renewable energy prices have been falling steadily over the last two decades, whilst more recently fossil fuel prices have soared.  The extent of the differential in some sectors is now staggering: generating electricity through offshore wind power is now four times cheaper than gas (Analysis: Record-low price for UK offshore wind is four times cheaper than gas – Carbon Brief).  There are of course still challenges to overcome, including storage capacity and how to heat homes that are currently heated with gas but there is progress in these areas too.  Reducing costs and achieving Net Zero can and should go hand-in-hand.  One of the quickest ways to bring down both bills and emissions is to support people in reducing the need for energy by better insulation and energy efficiency in our homes.

The ‘net’ in Net Zero is important.  In a natural carbon cycle there are emissions (including from respiration by organisms) and removals.  At present the world’s ecosystems remove a large proportion of human fossil fuel emissions from the atmosphere but their degradation and destruction, especially through deforestation is also major sources of emissions.  The protection and restoration of natural systems are therefore key elements of achieving Net Zero, as well as providing multiple benefits for people and being the right thing to do in their own right as far as many of us are concerned.  It doesn’t remove the need to phase out fossil fuels but as the Earth’s ecosystems recover they can balance out the most difficult to eliminate emissions; technological approaches may also help to ease the transition to a low carbon world.

There is much more that could be said.  Net Zero isn’t an easy objective to achieve and requires innovation, commitment and investment; it will also need to be achieved in a way that supports the most poor and vulnerable.  However all the nations of the world have committed to it and the alternative is far worse – ever increasing climate change with escalating impacts and devastating losses in which the poor and vulnerable will suffer most.

Dr Mike Morecroft is President of JRI