On Monday, the Intergovernmental Panel on Climate Change published a new report, the Sixth Assessment Report. This report reaffirms what the global body of scientists, activists, and leaders pushing for climate action have been saying for many years: climate change is real, it has arrived, and it's bad — but we can still fix it.
Kids Fight Climate Change created this summary of the IPCC's report so that you can succinctly and digestibly understand it, including how the IPCC reaffirmed that climate change is happening, the effects are here, and that our current action is not enough to keep warming under the dangerous 2ºC mark. But the report also showed us a way out: if we take climate action now, we can still stop these devastating effects.
I. The Earth is Warming
“It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.”
(Summary for Policymakers, 5)
The IPCC opened its Summary to Policymakers with these sentences. It quickly reaffirmed that climate change is real, refuting climate deniers once more. Later, the report put a number to this human-caused warming: approximately 1.1°C (with a 0.2-3ºC error in both directions) since the 19th century. Even more damning is the fact that temperatures have increased since 1970 faster than any other 50-year-period in at least the last two thousand years.
II. The Effects are Here — And It's Climate Change
The IPCC once again told us about the effects of climate change and proved with even greater certainty that they are attributable to climate change. Furthermore, they showed us that climate change is already happening.
“Climate change is already affecting every inhabited region across the globe with human influence contributing to many observed changes in weather and climate extremes”
(Summary for Policymakers, 12)
The report also concluded that climate change caused sea levels to rise by 8 inches since 1900, which is actually a significant amount when you consider how close billions of people live to the sea level. Indeed, this rate is faster than any other century in the past 3,000 years!
Furthermore, the IPCC showed us that humans are the reason that glaciers are melting across the world, that climate change contributed to the decrease in snow cover in the Northern Hemisphere.
Finally, "human-induced climate change is already affecting many weather and climate extremes in every region across the globe," said the report. The IPCC found a 99-100% probability that heat waves are increasing due to climate change. The report also concluded that climate change is increasing deluge (heavy rain), drought,
These are just a sampling of the many effects of climate change the IPCC promised will happen now.
III. Climate Futures
“We can expect a significant jump in extreme weather over the next 20 or 30 years. Things are unfortunately likely to get worse than they are today,”
said Piers Forster, a climate scientist at the University of Leeds who worked on the report. That's because the report concluded that warming will exceed 2ºC if we don't immediately cut greenhouse gas emissions. What's perhaps even more significant is that there is no future where we don't reach 1.5ºC of warming. In 2018, the IPCC published a report detailing what would happen if we reached 1.5ºC; this 2021 report indicates even more devastating (and unavoidable) futures in the 1.5ºC world. The IPCC created a handy table to show the warming levels across the next 100 years for each of the five scenarios they analyzed.
To be more specific, the IPCC report considered five different futures. These futures were developed in two parts. First, they developed five Shared Socioeconomic Pathways (number 1-5) which combine climate action with other factors which will impact climate policy, including international relations, global poverty and inequality. Then, they combined the SSPs with something called radiative forcing, which is just a fancy way of saying how much greenhouse gases contribute to climate change based on their concentration in our atmosphere. For this report, the IPCC used SSP 1-1.9 (meaning an SSP of 1 and a radiative forcing of 1.9), 1-2.6, 2-4.5, 3-7.0, and 5-8.5. You can view an infographic developed by the IPCC showing these scenarios here.
The third scenario (SSP2-4.5) is what the IPCC says will happen if we meet the very upper level of the Paris Climate Agreement. That means that even with the most aggressive international climate action proposed, we will exceed 2ºC of warming by mid-century! This is a devastating revelation, showing the world that the time to act is now.
IV. How to Stop It
So far, this summary has focused only on what's bad. But that's not all the report told us: it also told us (and policymakers) how to stop climate change.
“From a physical science perspective, limiting human-induced global warming to a specific level requires limiting cumulative CO2 emissions, reaching at least net zero CO2 emissions, along with strong reductions in other greenhouse gas emissions. Strong, rapid and sustained reductions in CH4 emissions would also limit the warming effect resulting from declining aerosol pollution and would improve air quality.”
(Summary for Policymakers, 36. Emphasis added.)
If we achieved net-zero emissions by 2050 across the entire world, we have a chance of reaching the 1-1.9 or 1-2.6 scenarios. However, this would also need net negative emissions throughout the rest of the century.
Although we can no longer limit warming below the 1.5ºC level, the report confirms that we still have an opportunity to fix climate change. It will require activists, policymakers, lobbyists, and all sorts of change makers to work together to solve the climate crisis.
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