The next big report from the world’s leading climate scientists is on impacts, it’s due the end of March, and it isn’t pretty. As the AP summarized the draft report on “Impacts, Adaptation, and Vulnerability” from The Intergovernmental Panel on Climate Change, “starvation, poverty, flooding, heat waves, droughts, war and disease [are] likely to worsen as the world warms from man-made climate change.”
Stanford’s Chris Field, who co-chairs the working group drafting the report, told reporters Monday that “the impacts of climate change that have already occurred are very evident, they’re widespread, they have consequences.” One key point Field made is that we are not prepared for the kind of warming-worsened extreme weather — like floods and droughts — we’re already experiencing: “I think if you look around the world at the damages that have been sustained in a wide range of climate-related events, it’s very clear we’re not prepared for the kinds of event we’re already seeing.”
In November, Climate Progress reported on a leaked early draft of the report, which read in part, “Throughout the 21st century, climate change impacts will slow down economic growth and poverty reduction, further erode food security and trigger new poverty traps, the latter particularly in urban areas and emerging hotspots of hunger.” The report warns that climate change poses an extreme threat to food security and water security for billions of people by mid-century.
I asked leading climatologist Dr. Michael Mann for his comment. The director of the Earth System Science Center at Pennsylvania State University said:
The latest IPCC climate change impacts report reinforces what we already knew: that climate change is already having a detrimental impact on us and our environment, whether we’re talking about food, water, land, national security, or the health of the ecosystems we so critically depend on. The report also makes clear that what we’ve seen is only the tip of the veritable iceberg. If we continue with business as usual fossil fuel emission in the decades ahead, the report shows, the resulting warming and change in climate will inflict far more dangerous and potentially irreversible impacts on us and the planet.
The good news is that a world in which humans slash carbon pollution ASAP has substantially lower impacts than one in which emissions remain high.
Field noted that, “There’s really a big, big difference between what those worlds look like,” said Field.
You can see that in the top figure, which is from the September IPCC report on “The Physical Science Basis.” The window for achieving the RCP2.6 scenario — which is am atmospheric concentration of carbon dioxide of about 421 parts per million — is closing fast, but not yet shut. It has modest overall warming compared to the devastating RCP 8.5 scenario, about 936 ppm CO2, which is where we are headed on our current do-little path.
Mann adds that warming-worsened extreme weather is here now and very costly:
There is no doubt, when we look at the increased toll that climate change is taking in form of more devastating superstorms, more prolonged and severe drought, more extreme flooding events, decimated agriculture and livestock, and massive wildfires, that we are already feeling the adverse impacts of climate change. Economists have estimated that climate-related damages are already costing us more than 1 trillion dollars worldwide in global GDP. Those costs will only rise if we do nothing about this problem.
For more on the trillion-dollar estimate, see here. The International Energy Agency informed as as far back as 2009 that “The world will have to spend an extra $500 billion to cut carbon emissions for each year it delays implementing a major assault on global warming.”
The time to act is now.