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Less than 100 days before COP 26, during a summer marked by devastating floods, droughts and fires, the first part of the 6th assessment report from the Intergovernmental Panel on Climate Change (IPCC) has been published. Unveiled on Monday August 9th 2021, the conclusion of this new scientific work on climate is more alarming than ever.
What is it and why is it so important?
As part of its 6th assessment report, this report entitled “Climate Change 2021: The Physical Science Basis” comes from the first IPCC working group on the scientific aspects of the climate system and climate change. It draws up a very precise inventory of climate physics, and is the most important source regarding scientific knowledge on climate change around the world. Its importance is crucial on the eve of COP 26, which will bring together the leaders of hundreds of countries and will be decisive for our future.
What should you remember about the state of the climate?
We already knew it, but it is now a fact established by science: human activity is the cause of the atmosphere, oceans, and land warming. This report sets it in stone. It also shows that much of the damage caused by climate change is now irreversible, such as the rise in sea levels.
“Furthermore, there are additional potentially uncontrollable elements that are still poorly understood: the slowing down of the Atlantic Meridional Overturning Circulation (a very large Atlantic current carrying hot water northward), bringing it potentially close to collapse, massive ocean acidification, the melting of permafrost or the fracturing of the Antarctic ice sheet. These elements could constitute powerful destabilization agents within the climate system and accelerate its transformation.”
Other striking findings: “Each of the past four decades has been successively warmer than any previous decade since 1850”. “The magnitude of recent changes in the entire climate system and the current state of many aspects of the climate system are unprecedented over several centuries to several thousand years.”
What are the possible climatic futures?
This report focuses on three models out of five analysed scenarios:
- One where warming is limited to 1.5°C compared to the pre-industrial era,
- A second where the planetary temperature increases by 2°C compared to its pre-industrial level,
- A third where the warming reaches up to 4°C.
The report underlines that the 1st threshold of 1.5°C will lead to serious and sometimes irreversible consequences for centuries. This level of warming could already be exceeded in 2030, 10 years earlier than anticipated by the IPCC’s last report.
The first two scenarios assume that most fossil fuels will no longer be used, which implies deep socio-cultural, technological, economic, and political transformations.
The first would imply a drastic reduction in global emissions at an accelerated rate, which, given the current state of mobilization, makes its economic, social and political probability null.
The second warming scenario – below 2°C of warming – assumes the commitment of effective, ambitious, and coordinated climate policies in terms of restricting the use of fossil fuels, especially during this decade.
These are all alarming elements that underline the fact that this decade represents our last chance to implement climate policies and strategies that meet vital global challenges.
We really have no other choice but to embrace one of the two more ambitious scenarios. The window is closing. We have very little time to act.
Focus on the remaining carbon budget
The report also addresses the carbon budget that would allow us to respect the 1.5°C and 2°C trajectories. Humanity has emitted 2,560 billion equivalent tons of CO2 since 1750, and we only have a budget of 500 more if we want to limit warming to 1.5°C.
By following a trajectory of very low GHG emissions (SSP1-1.9), the threshold of 1.5°C will be reached in the short term, between 2021 and 2040, before being very slightly exceeded (1.6°C anticipated over the period 2041-2060) then respected in the long term (1.4°C anticipated over the period 2081-2100).
Everything is not lost, but we must pursue the Paris Agreement’s most ambitious goal of limiting warming to 1.5°C.
Towards enhanced international and regional cooperation
With this report, the IPCC examines for the first time the regional aspects of climate change. Because of worsening climate change, the IPCC warns that each region is expected to experience more and more simultaneous and multiple changes in climate impact factors, even with a global warming of 1.5°C.
States have a key role to play. The only possible scenario to reach the Paris Agreement’s most ambitious goal includes full and coordinated cooperation between all countries. A country or a region can’t act by itself to meet the collective and planetary challenges which affect all areas of the globe, often irreversibly.
States must walk the talk in favour of net zero by concretely strengthening their national contributions (NDC) by 2030, and by respecting these commitments.
The indispensable contribution of companies
All companies must act without delay: massively reduce their direct and indirect emissions along a path based on scientific data aligned with the 1.5°C target, contributing to carbon neutrality and developing eco-innovation.
Their actions must not only be immediately engaged on an unprecedented scale, but also supported in an ambitious strategy towards net zero in the long term. They must be sanctioned if they do not play by the rules, because all of the tools they need to succeed already exist.
Innovation, while essential, cannot by itself solve climate change. A deep and rapid change in economic models and in our way of life, methods of production and consumption is needed.
Now is our time to limit climate change
The observation is clear: it is essential for each economic actor to immediately adopt an aggressive strategy to reduce GHG emissions. We can’t wait; it will take years for our actions to have an effect (20 years minimum). The reduction of our global emissions must be drastic, sustainable and effective on the very near horizon in order to have systemic benefits on air quality and the stabilization of global temperatures within 20 to 30 years.
These conclusions demand collective action to transform our economy and our behaviours at all levels: individuals, communities, businesses, institutions, and governments. This means going beyond current action plans, and very quickly, otherwise the 1.5°C target by the end of the century will be beyond our reach.
Facing the danger of the cascading effects of climate change, every fraction of each additional degree counts in determining our future. This report is a call to push the boundaries of our ambition.
All attention is now focused on the COP 26, that will be held from November 1 to 12 in Glasgow to implement climate policies aligned with IPCC’s conclusions. Even so, only eight countries have published a more ambitious NDC than their previous one, leaving a gap to close in order to comply with the 1.5°C carbon budget by 2030.