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Inches & Eons: climate change at 1.5°C

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An inch is a very short distance and an eon is a very long time.  Some might say that in terms of climate action the global community has moved mere inches in the eons we’ve known that human actions are warming our world.  So it is perhaps appropriate that next week the Intergovernmental Panel on Climate Change (IPCC) goes to Incheon, Korea, to highlight the importance of the Paris Agreement’s 1.5°C global warming limit.

What is the IPCC?

The IPCC produces global assessments on the state of the climate as well as so-called “Special Reports” on tricky topics such as aviation or carbon dioxide capture and storage.  IPCC reports are authoritative sources of information and underpin the international community’s understanding of climate change. Their reports are huge (they run to hundreds if not thousands of pages), and hugely influential.  The IPCC is a millennial – it turns thirty this year – and shared the Nobel Peace Prize with Al Gore in 2007.

There is no other organisation quite like the IPCC in its process of writing reports.  They are the culmination of efforts from hundreds of scientists around the globe. These experts consider the latest information from many disciplines from physical sciences to climate impacts to climate solutions.  Thousands more reviewers help the authors improve the drafts.

Arguably the most important output from each report is the “summary for policymakers”,  agreed line-by-line by the 195 IPCC country members to give the seal of approval of government ownership.

And it is doing a Special Report on 1.5°C?

In Incheon, the IPCC is due to approve the summary for policymakers of its Special Report on Global Warming of 1.5°C.  This report will be a critical input to the 2018 Talanoa dialogue, a process in the UN climate negotiations meant to help ramp-up ambitions under the Paris Agreement before 2020.

Why look at 1.5°C?

The existential threat of climate change to some vulnerable and island countries was the spur for the Paris Agreement’s goal to limit global warming to well below 2°C above pre-industrial levels and to pursue efforts to 1.5°C.  This stimulated scientists to focus research on 1.5°C. The special report will assess this new literature and bring the findings together. Recent science has highlighted several things:

Climate change impacts are happening now

This is a reminder not to put things off.  The current ~1°C of global warming is already having impacts and causing damage including in the form of extreme and dangerous weather events – for example the global heatwave this summer, expansive wildfires and deadly hurricanes.  We need to adapt and build resilience, and this will only become more pressing at higher temperatures.

1.5°C is safer than 2°C for people and nature

We already know higher global temperatures lead to greater climate impacts – on land, in the oceans, and the in polar regions.  But we can now better quantify by how much. For example, nearly 700 million people (9.0% of world population) will be exposed to extreme heat waves at least once every 20 years in a 1.5°C world, but more than 2 billion people (28.2%) in a 2°C world.  Similarly in a 1.5°C world, the end of the century projection is that 70% of tropical coral reefs are at risk of severe degradation due to temperature-induced bleaching, but virtually all in a 2°C world.

Breaching 1.5°C is not inevitable

There are options for 1.5°C and we know the things that need to be in place.  Political leadership is important. So are individual choices.  Strong leadership and the right choices can lead to the necessary rapid and deep cuts to greenhouse gas emissions, which improves the chance of limiting warming to 1.5°C.  For example, governments encouraging renewable energy over fossil fuels and individuals choosing to eat a healthy, more plant-based diet. This is not to belittle the unprecedented scale of the challenge ahead but shows 1.5°C is not a lost cause.

“Net-zero emissions” are needed

It is better to not pollute in the first place, so rapid and deep cuts are a priority – these are necessary but not sufficient.  Actively removing carbon dioxide from the atmosphere to balance out any hard-to-mitigate residual emissions must also happen. We know that land-based carbon dioxide removal options such as forest restoration can have benefits over and above climate mitigation and are a better immediate focus than more technological removal options.  The balance between carbon emissions and carbon removals needs to happen globally around mid-century, and sooner in developed countries such as the UK.

WWF and the IPCC

WWF is engaging in the scientific developments around 1.5°C with great interest.  We will be in Incheon to ensure that governments, businesses and the public can take actions informed by the best scientific information.  In particular that 1.5°C is safer than global warming of 2°C or higher – and that we have choices which make a difference.

Time is short – we have have years not eons to sort this out, and we’ve miles, not inches to go.

  • Read WWF’s expectations for the IPCC meeting in Korea here

Dr Stephen Cornelius is the chief advisor for climate change for WWF-UK. Follow him on twitter @SteveJCornelius

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