IPCC 6th Report Summary
9 September 2021
One month ago the IPCC (Intergovernmental Panel on Climate Change, a UN-dependent transnational body) released its sixth climate assessment report.
The difference between this sixth report and the previous ones lies in the improvement of climate models, thanks to the incorporation of more data and the increase in computing power. This allows to reduce results variability and to make more accurate predictions.
However, it also shows the limitation of the models. They don’t fully include the effects of warming on certain ecosystems: permafrost thawing, loss of wetlands and forest fires. The three of them important greenhouse gas phenomena.
The report can be summarized in four main conclusions. But the bottom line is that we have no choice but to capture carbon dioxide and other greenhouse gases (GHG) from the atmosphere, as Greennova Foundation is trying to do with GRAFECO2 and CAPTACO2 projects.
Main report conclusions
1. It is indisputable that global warming, and consequently climate change, is caused by the humans.
2. Global warming has so much inertia that we will not be able to stop it until at least the middle of the century, even considering significant reductions in emissions. And once stopped, its effects will persist for centuries or millennia.
3. Adaptation measures will be unavoidable.
4. The magnitude of climate change will only be reduced by lowering emissions and by removing from the atmosphere already emitted greenhouse gases.
1. We are guilty
Man-made GHG emissions have led to the acidification of the oceans and the retreat of glaciers and Arctic ice. Also to more extreme weather events, such as droughts, torrential rains and cyclones. These changes never occured at least during the last 800,000 years.
Emissions of carbon dioxide and secondarily methane, have been the main contributors to the rise in temperature. In contrast, nitrogen oxides and sulfur dioxide have slowed this increase.
The additional warming caused by GHG emissions has accumulated almost entirely in the oceans, and to a lesser extent on the ground, melted ice, and the atmosphere.
The rise in sea level is then due to the thermal expansion of the oceans, but also to the melting of glaciers and ice sheets.
2. A system with a lot of inertia
Without slowing down emissions we will exceed 1.5º of temperature increase, always with greater warming on the ground than in the oceans.
More temperature will mean more extreme weather events, loss of snow surface and increased permafrost thawing. It will affect the intensity of the monsoons, with longer periods of drought and more intense and concentrated rains over time. And at the same time CO2 natural sinks will have less retention capacity.
In any case there are changes that we have already provoked and that will last for hundreds and thousands of years. These include acidification, deoxygenation and stratification of the oceans, melting glaciers, and rising sea levels.
3. We must adapt
Although certain phenomena may temporarily mask global warming, it will go on. Moreover, the attenuation of the temperature rise will be increasingly difficult.
Particularly in cities, urbanization increases the effect of heat waves. Worse if they are on the coast, where floods will be much more likely.
There are certain scenarios of very profound changes that cannot be ruled out. These include the melting of important parts of Antarctica, the decline of the forest mass and changes in ocean currents that modulate the climate.
4. Reduce and clean up GHGs
To limit the damage that is already causing global warming, it is essential to reduce emissions and extract GHG from the atmosphere. This would also have a positive effect on air quality.
However, once we become carbon negative, that is, we clean more GHG than we emit, the changes that global warming has already caused will continue with us for hundreds and thousands of years.
The full report can be downloaded from the IPCC website, www.ipcc.ch