What Is Happening?
The planet is getting hotter due to human action
Specifically, it is the amount of greenhouse gasses (primarily carbon dioxide and methane) emitted into the atmosphere that is to blame.
More greenhouse gases mean more heating.
And more heating affects every aspect of our ecosystem and our lives - from health effects to food price and availability, changing ecosystems (SF will resemble LA by 2100), and leading to mass migrations.
Warming stripes based on WMO global annual data show the increase of average global temperatures from 1850 (left) to 2018 (right).
Created by climatologist Ed Hawkins. CC BY-SA 4.0
– in brief:
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Since 1900, greenhouse gas emissions have raised the baseline temperature of our planet more than 1 degree Celsius (1.8 degrees F). The world is now the warmest it has been in the last 12,000 years. [more]
– THE 1℃ DOESN’T SOUND LIKE MUCH
But it has already brought heat waves, fires, drought, flooding, and sea level rise. Further heating would have far more dramatic effects. [see here]
– WHERE DO WE STAND NOW?
Current plans to cut emissions put us on path to reach 2.7 degree C (4.8 F) warming above pre-industrial levels. [source]
That’s really bad.
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VERY. [Nasa’s evidence summary]
Conclusions about human-caused global heating are based on:
historical temperature records [data sample]
major temperature-related changes observed over the past 100 years [read more]
A great number of scientific studies published in peer-reviewed scientific journals show almost universal agreement among climate scientists - the latest IPCC report alone is built on 34,000 scientific studies, and scientific institutions stand behind those claims. [source]
In the words of the climate scientist Michael Mann, “There’s about as much scientific consensus about human-caused climate change as there is about gravity.” [watch Michael Mann on CBS’s “60 Minutes”]
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Interested in more detailed information?
– GLOBAL
The latest IPCC report has it all, but is quite a read. A great toe-dip is this concise Twitter summary of IPCC report’s main findings by climate scientists Prof. Kimberly Nicholas.
– LOCAL
The California Legislative Analyst’s Office issued a series of reports and a short summary (Spring 2022) that outline changes - and grave cost - that line ahead for Californians.
What happens next is up to us
There is a lot we can do to protect our community, our livelihoods, and our local ecosystem. Mitigation efforts are already underway in many parts of the world, including around the Bay.
But we must act now.
“The amount of change that we’re going to see—whether it’s serious, whether it’s dangerous, whether it’s devastating, whether it’s civilization-threatening—the amount of change we’re going to see is up to us, (...) It depends on our choices today and in the next few years.”