The science could not be clearer – greenhouse gas emissions over the last 150 years have pushed our planet to already be more than 1 degree Celsius warmer than it should otherwise be. In addition, continued greenhouse gas emissions will heat our planet beyond a level ever experienced by humanity and to a level unprecedented on Earth for millions of years. Also, the speed at which our greenhouse gas emissions change the atmosphere that envelopes our planet is several times faster than under any natural process over several hundreds of thousands of years past.
We are having a dramatic, obvious and dangerous impact on the habitability of Earth.
Halting global warming requires us to stop adding carbon dioxide to the atmosphere. If we want to go further and gradually undo global warming, we must start to actively take carbon dioxide out of the atmosphere and put it back in the ground. However, the greenhouse gas emissions of our society cannot drop to zero instantly, and this inertia means that we are locked into at least another half a degree of warming before things stabilize or can become better.
Worsening climate impacts should still be expected, therefore, even if we put in place the most ambitious of climate mitigation strategies. We must prepare for further extreme weather conditions, the like of which we are starting to see in the UK (damaging storm and flooding events) and overseas (with extensive and brutal wildfires in Australia and California). Future sea level might also continue to rise by at least a meter over the next centuries, but a multiple of that number will happen if we fail to bring down our greenhouse gas emissions.
Science allows us to understand and predict this unravelling catastrophe; it teaches us clearly what needs to be done to halt unnecessary warming; and we know this cannot happen overnight. Worse is still to come before the situation will be under control.
It does not take much to notice parallels with the current coronavirus pandemic.
First, both were predictable and predicted – even if it remains uncertain when precisely they will impact us. Second, attempts to prevent their occurrence have failed, and mitigating measures came too late. Third, our preparations to adapt to their impact are hampered by vested interests and business profit margins that take little account of planetary or societal stewardship.
The lesson of COVID-19 for climate change could not be clearer. Investments in a zero-carbon transition will avoid damaging environmental change, will ensue the planet is fit to support future generations and will cost far less in the long run than if we fail to do what is necessary. Current climate actions, however, are insufficient.
Decisions makers are taking increasing notice of the scientific message on climate change, and the need for widespread emissions reductions. But progress is too slow. Another lesson learned from COVID-19 is that science provides facts, evidence and options, but decision makers should not hide behind scientists for the complex societal decisions they are tasked to make. For climate change, science shows we can halt warming to a maximum of 1.5°C if our economies stop dumping their waste gases into the atmosphere by 2050. This is scientifically non-negotiable and requires actions that reduce emissions to start without delay. At the same time, science has identified a diverse range of available strategies to achieve these reductions. The choice of which strategy to pursue is a responsibility that lays with elected representatives and can only be informed, not dictated, by scientists.
The 2015 United Nations climate summit in Paris, known as COP21, made the first step by adopting an ambitious international climate agreement that puts a cap to the level of climate change considered acceptable to society: global warming is to be kept well below 2°C and preferably to no more than 1.5°C compared to preindustrial times. However, the Paris Agreement did not provide all that is needed to deliver the necessary reduction in global greenhouse gas emissions. This shortfall was acknowledged from the outset. Supported by authoritative scientific reports on climate impacts and solutions, meetings over the last few years had to debate how countries should adjust their climate policies to adequately address this shortfall.
This year, things get real. For the first time countries have the opportunity to come forward with new national climate action plans that are in line with what science tells us is needed to head off the predicted environmental disaster. The UK plays a central role in ensuring that these updated plans deliver the ‘ratcheting up’ of global climate ambition. In its role in holding the presidency for the next COP26 in Glasgow, the UK is responsible for leading the international diplomatic preparations that will be the basis of a successful climate summit.
The UK’s strategy for COP26 should be five-fold:
(1) to get the highest ambition on emissions reductions possible from individual nations;
(2) to champion and consolidate the central role of scientific evidence in effective policymaking;
(3) to encourage initiatives alongside the negotiations (e.g. commitments for zero-carbon or net zero greenhouse gases at some stage this century);
(4) to obtain pledges to finance green economy initiatives, especially in support of zero-carbon innovation; and (5) to construct a communications narrative to explain what the meeting achieves and what the next steps should be.
COVID-19 will have an obvious impact on the meeting. It has pushed the summit back to the latter half of 2021. This will offer some valuable time for the UK (and its co-host Italy) to undertake the kind of preparations and behind the scenes discussions that made France so effective in the run up to COP21.
The lesson from the pandemic is clear: when you see disaster coming that the science is certain of – do something ahead of time. Failure will lead to colossal economic damage in addition to the human cost. The challenge to world leaders is to heed this lesson and COP26 in Glasgow will be the first opportunity they have to show what collectively they will do. In a world shocked by the fallout of COVID-19 misinformation, scientific evidence and integrity will be the benchmark against which the success of the UK’s COP26 presidency will undoubtedly be measured.
More information about the Grantham Insitute is available on their website.
Photo Credit: Imperial College London
Martin Siegert is the co-Director of the Grantham Institute - Climate Change and Environment - at Imperial College London and Joeri Rogelj serves as a Lead Author to the Intergovernmental Panel on Climate Change (IPCC) and is a Lecturer at the Grantham Institute at Imperial.