As you may have seen in one of the many recent articles plastered with images of the world burning, the UN backed International Panel on Climate Change (IPCC) has released the first version of its 6th Assessment report on Climate Change. The full report clocks in around 1300 pages, so this article will help explain some of the important findings in this report, particularly the summary for policymakers, by breaking them down. 

First is the current state of climate change. The report states, “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.” This means with the highest certainty, that human caused climate change and destability is occurring, and we are already seeing the effects of it. The report also found that “The scale of recent changes across the climate system as a whole and the present state of many aspects of the climate system are unprecedented over many centuries to many thousands of years.” We are currently seeing the effects of climate change, and they have not occurred in the historical analysis over thousands of years. The climate crisis cannot be reduced to an ever changing planet. It is the result of human activity – and cannot be solved without drastic changes in human activity. The report also explains that “Human-induced climate change is already affecting many weather and climate extremes in every region across the globe. Evidence of observed changes in extremes such as heatwaves, heavy precipitation, droughts, and tropical cyclones and their attribution to human influence, has strengthened since AR5.” This means we are already seeing the effects of the climate crisis. 

Warming is currently around 1℃, and the past few years have seen increasing wildfires, extreme temperatures, drought, increased rain, and more occurrences of natural disasters. Lastly, the report found that, “Improved knowledge of climate processes, paleoclimate evidence and the response of the climate system to increasing radiative forcing gives a best estimate of equilibrium climate sensitivity of 3°C with a narrower range compared to AR5.” Climate sensitivity translates to the estimated temperature changes in our climate in the coming decades. While previous assessments have contained frustratingly large margins of estimate, the recent report narrows that to an estimated range of 2.5℃ to 4℃, with a best estimate of 3℃. This means the next few decades will likely contain an average global warming of 3℃, unless drastic changes are made. 

The next section of the report contains information regarding possible climate futures. The first finding is that “Global surface temperature will continue to increase until at least the mid-century under all emissions scenarios considered. Global warming of 1.5°C and 2°C will be exceeded during the 21st century unless deep reductions in CO2 and other greenhouse gas emissions occur in the coming decades.” Unlike previous climate assessments, this report has found we are past the point of preventing or undoing significant climate changes, and in any case we will likely see global temperatures hit a 1.5℃ increase by 2100. In the better case scenarios the increase can likely be kept under 2℃, but in worse and as usual scenarios, we could see global temperature increases of up to 5℃ or more. This would drastically change our climate and destabilize many areas of the world. With each increase, the world will see more effects such as extreme heat and cold, rising sea levels, polar ice melting, drought and monsoons, and disasters such as tropical storms. The report has also found that at this point, the undoing of certain changes such as ice sheets, sea levels, and the ocean cannot be undone in any scenario. 

Lastly, the report again showed that “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.” It has never been so important for countries to commit to reducing CO2 emissions. The report has shown that net zero CO2 emissions are necessary to reach better case climate scenarios. This means that emissions reductions goals must be increased, and climate policy is necessary to follow through with this. 

While the world is not going to set ablaze tomorrow, this report shows how vital environmental action truly is. Now is the time to take drastic actions – most importantly calling on our leaders and corporations to make the change.

Citations:

The full report – https://www.ipcc.ch/report/ar6/wg1/#SPM