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It’s now or never for one and a half degrees


Today the Intergovernmental Panel on Climate Change (IPCC) published its Special Report on ‘Global Warming of 1.5°C’. Mike Thompson, Head of Carbon Budgets at the Committee on Climate Change (CCC) reflects on the report and what it means for the Committee’s next phase of work.

“I hope you’ll tear it up”. That was Lord Adair Turner’s tongue-in-cheek advice for anyone still in possession of a copy of the CCC’s first report from 2008 when the former CCC Chair spoke at the 10-year anniversary of the LSE Grantham Institute last week. Much of the report still stands up to scrutiny, but in retrospect we were woefully conservative on the scope for renewable and battery costs to fall. Today’s IPCC report recognises the rapid technical progress, but unless governments do much more to drive cuts in emissions, its scenarios will rapidly diverge from reality and part of the battle to tackle climate change will be lost.

The plummeting costs of wind and solar power and of batteries – along with the benefits they bring for other priorities like local air quality and energy sovereignty – are a game-changer when it comes to the global fight against climate change. Power generation is a major source of CO2 emissions globally, while cleaner, low-carbon electricity coupled with energy storage brings the potential also to shift other polluting sectors of the economy away from fossil fuels. This promise is the source for the closest thing to optimism in today’s IPCC report, which states: “The energy system transition that would be required to limit global warming to 1.5°C is underway in many sectors and regions around the world”.

That is a big change from 2008 and today’s IPCC report addresses another. In 2008, the world had no agreed goal to aim for in terms of limiting increases in global average temperature. Now we have the international consensus of the 2015 Paris Agreement, and its headline goal to ensure temperature rise stays well below 2°C and to pursue efforts towards 1.5°C above pre-industrial levels.

At the time, not much was known about how 1.5°C could be delivered (just two pathways had been published) – or what level of climate damage might be avoided by doing so. In 2016 we advised that the UK should focus on cutting emissions now, maintain options to go further and then return to review longer-term emissions targets once more evidence became available.

Today’s IPCC report doesn’t make for comfortable reading – limiting warming to beneath 1.5°C will be very, very difficult whilst it is clear that the climate damages at 2°C of warming (never mind the 3°C that current global ambition is on track for) will be a lot worse than those at 1.5°C. However, we have a much clearer understanding of how such an ambitious and rapid transition in the world’s economy could be achieved (now from dozens of detailed IPCC scenarios) – and the report is clear that technically it is still possible, with “transformative systemic change”.

Perhaps most uncomfortable is the short window for ramping up global effort – a key demand of the Paris Agreement. The IPCC’s report is confident in stating that the 2030 emissions reduction effort pledged in Paris “would not limit global warming to 1.5°C, even if supplemented by very challenging increases in the scale and ambition of emissions reductions after 2030.” We already have 1°C of warming, and if the world doesn’t start doing a lot more a lot quicker, then the window for meeting 1.5°C will close too. It will then be time to tear up this report and say goodbye to coral reefs and say hello to a lot more heatwaves, flooding, water shortages and falling crop yields. The UK will be affected by these climate change impacts directly, as well as indirectly from those occurring globally.

Given the strengthened international ambition and progress in developing low-carbon technologies, the UK Government has committed to a net-zero emissions target and said it will ask the CCC to review the UK’s long-term climate targets in light of the strengthening evidence base. That review makes sense at the time of the Climate Change Act’s own 10-year anniversary this November. The Act has stood the test of time well, but the world is changing around us.

We await the Government’s formal request for our advice on long-term emissions targets, but some questions we expect to consider in forming that advice include:

  • How can the world deliver on the Paris Agreement’s temperature goal?
  • What is an appropriate UK contribution to the global effort?
  • How can the UK reach very deep emissions reductions, including ‘net-zero’ emissions?
  • What are the costs, risks and opportunities for the UK from setting more ambitious long-term targets?

We genuinely don’t know yet where the answers to those questions will take us, but today’s IPCC report gives us a good deal more evidence to consider. We will be seeking wide input through a new Call for Evidence later this year, once we have received the Government’s formal request. We expect to publish our report in the first half of next year.

The CCC’s inaugural advice in 2008 (still prized in some quarters!) was titled ‘Building a low-carbon economy’. The question has changed. Now, we want to build a zero-carbon economy. And whatever the Committee concludes next year, the UK and the world need to get on with it.