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“The climate time bomb is ticking. But today’s IPCC report is a how-to guide to defuse the climate time bomb. It is a survival guide for humanity." The UN secretary general António Guterres does not usually mince words when it comes to the climate crisis. Nor did he while announcing the release of the key scientific report that will be the final word as a guide to climate action till 2030.
The next seven years will be momentous, for good or for ill. By 2030, the world’s governments would have either found the will to reverse the climate catastrophe that threatens the planet, or not. The choice is a simple one, as the report, Climate Change 2023, clearly shows. It is a “synthesis report" that brings together the key findings of three special reports and three assessment reports, released between 2018-22.
The state of the climate
These reports constitute the sixth such roundup of current scientific knowledge on the climate crisis. Prepared by the UN’s top climate science body, the IPCC, the Assessment Report 6 (AR6) cycle formally came to an end with the publication of the concise Climate Change 2023 report on 20 March.
It has been described as a “final warning" from scientists to the world’s governments,. The previous round, AR5, finished in 2014, and the report was the key scientific document that helped shape the historic 2015 Paris Climate Agreement. Work on AR6 began the same year.
Nine years is a long time when it comes to the climate crisis. In 2014, Earth’s atmospheric concentration of CO2—the main planet-heating greenhouse gas (GHG)—was 397.45 ppm (parts per million). In 2023, that stands at over 418 ppm. For context, in 1850 (the baseline year for global warming assessments), it was 284.7ppm. The current synthesis report found that atmospheric CO2 concentrations today are higher than “at any time in at least 2 million years". The amount of methane, another major planet-heating gas, in the atmosphere is the highest it has been for 800,000 years.
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What this means is that the heat trapped by GHG emissions has pushed the global average temperature up by nearly 1.2 degrees Celsius since 1850. The relatively “safe" threshold of heating that the world should not cross is 1.5 degrees Celsius, and the aim of governments under the UN Framework Convention on Climate Change (UNFCCC) is to limit warming to 1.5 degree Celsius above 1850 levels, by 2100.
However, given the high concentrations of GHG in the atmosphere, and the fact that global GHG emissions are increasing instead of declining, scientists have predicted that the 1.5-degree threshold will be crossed, at least temporarily, by 2030. The Climate Change 2023 report is clear that an overshoot of this limit is inevitable but deep and sustained cuts to fresh emissions—leading to net negative emissions after 2050—would mean that global heating can be brought back down to the 1.5 degrees Celsius, or lower, by the end of the century.
But for that to happen, urgent action is required. Fresh CO2 emissions need to peak by 2025 and decline by nearly half by 2030. If the world continues at current levels of emissions, then we are looking at a temperature rise of 2.8 degrees Celsius by the end of the century. That would be calamitous for the welfare of human beings and ecosystems worldwide. This fact was firmly established by one of the special reports of the AR6 cycle—the so-called “1.5-degree report" from 2018—which fundamentally reset the frame of reference for climate action.
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The timing of the report also assumes importance because this is the year of the Global Stocktake. This mechanism is a key part of the Paris Agreement, which requires countries to publicly assess their work so far in meeting climate goals. The process will determine whether countries ramp up the ambition of their respective climate action programmes. This will ultimately affect the overall trajectory of meeting the emission targets set out by the IPCC for meeting the 1.5-degree goal. Current national ambitions, especially for countries such as US, China and even India, are woefully inadequate. The stocktake is expected to come to a head at the COP28 international climate conference in Dubai, which begins on 30 November.
What Indian scientists say
Although the synthesis report does not produce any new science—it is, after all, a “synthesis"—it may be the most vital document of the AR6 cycle. Speaking to Lounge, IPCC scientist Minal Pathak says that the synthesis is important not just because it marks the culmination of a set of groundbreaking science reports dating back to 2018, but also because it is aimed squarely at policymakers.
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“Between 2018 and now, we haven’t really made the progress that we should have. And that’s why this report becomes significant. In order to reach the 1.5-degree goal, deep and ambitious reductions are necessary. Five years down the line, we are still saying the same thing. I strongly feel that this report should be taken very seriously by governments at all levels," says Pathak, a member of the core writing team of the synthesis report. She is a faculty member at Ahmedabad University’s Global Centre for Environment and Energy. Pathak adds that it is important to keep repeating the scientific warnings until there is meaningful action.
“I would describe the report as a fitting synthesis of what we know on climate change—the magnitude of the problem, its various solutions, and pathways we need to take as a society," says scientist Chandni Singh, who is part of the writing team of the synthesis report. “I have been part of this assessment cycle since work began on the 1.5 Special Report in 2016. So, this synthesis, the end of the AR6 cycle, is also personal. As scientists, we have spoken, in clear unequivocal terms, about the problem and the opportunity." Singh is a senior researcher and faculty member at the Bengaluru-based Indian Institute for Human Settlements’ School of Environment and Sustainability.
For climate scientist Aditi Mukherji, another member of the core writing team of the report, the document lays out the challenges of the climate crisis, but also the solutions. “The synthesis report is a repository of our best available climate science that is also hugely policy-relevant. The report has a list of options—adaptation, mitigation and finance—that the countries have at their disposal, depending on their national circumstances." Mukherji, who is director, Climate Adaptation and Mitigation Impact Area Platform at the International Water Management Institute (IWMI), believes that there is now enough scientific evidence for governments to act.
Pathak says that while there certainly is enough evidence, there is a need for country-specific, or even region-specific, synthesis reports, especially for a country like India. At the very least, there should be regular, institutionalised monitoring and progress of endeavours such as state action plans on climate change. “We don’t have a dynamic and ongoing process on risk assessment, or on climate science, or on greenhouse gas inventories," she says, adding that such reports would also facilitate cross-learning between states, cities and regions.
“The constant drumbeat of extreme weather events has placed climate change in the public eye. Policymakers too understand this and nationally, there is a lot more interest in the science, a lot more appetite for action," says Singh. She adds that despite this, climate action is “piecemeal and reactive". “To me, climate issues must come on to party manifestoes, into daily conversations in schools, and in our newsrooms. It’s a whole-of-society issue and must be treated as such."
Although important climate research will continue, as far as a global “state of the climate" statement goes, the scientists have had their say for now. For Indian scientists like Pathak, Singh and Mukherji, being part of this process has left them both exhausted and energised. “It has been a very interesting, exciting, overwhelming process for me as a person and a scientist," says Pathak, “It has helped me grow as a person."
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Mukherji’s IPCC journey began as a review editor for the 2019 special report on the effects of climate change on the ocean and cryosphere. “It has been such an enriching experience, working in different capacities, and a huge learning curve," she says.
For Singh, her IPCC work has instilled a passion to decolonise narratives of climate research. “Being an IPCC author is a tremendous, tiring, exhilarating experience. I went into the IPCC a climate researcher but have come out a crusader for inclusive knowledge systems."