Code Red for Humanity – IPCC Report Unequivocal; A Must Read

This is a major development.  Here’s a summary of the report itself and what other people are saying about it.

Major Coverage:

• NY Times: A Hotter Future Is Certain, Climate Panel Warns. But How Hot Is Up to Us.
  Some devastating impacts of global warming are now unavoidable, a major new scientific report finds. But there is still a short window to stop things from getting even worse.
• Washington Post: Humans have pushed the climate into ‘unprecedented’ territory, landmark U.N. report finds
  U.N. chief calls findings ‘a code red for humanity’ with worse climate impacts to come unless greenhouse gas pollution falls dramatically.
• Wall StreetJournal – Some Climate Change Effects May Be Irreversible, U.N. Panel Says
  Report highlights human responsibility for heat waves, droughts, intense storms and other extreme weather events
• The Guardian – Worst polluting countries must make drastic carbon cuts, says Cop26 chief
  Alok Sharma says chance to limit worst impacts of climate breakdown ‘still achievable, but retreating fast’
  • IPCC’s starkest warning yet / Major climate changes inevitable and irreversible, warns report
    Report warns temperatures likely to rise by more than 1.5C bringing widespread extreme weather
  • The science / Climate crisis ‘unequivocally’ caused by human activities, says IPCC
  • Analysis / IPCC report’s verdict on climate crimes of humanity: guilty as hell
  • Explainer / What is the IPCC and why is its new climate report different from others?
  • Opinion / It should not come as a surprise that climate change is worse than we thought and also getting worser
    (by First Dog on the Moon)

Five Takeaways

1. BLAMING HUMANS  –  The report says almost all of the warming that has occurred since pre-industrial times was caused by the release of heat-trapping gases such as carbon dioxide and methane. Much of that is the result of humans burning fossil fuels — coal, oil, wood and natural gas.  The authors say global temperatures have already risen by 1.1 degrees Celsius (2 degrees Fahrenheit) since the 19th century, reaching their highest in over 100,000 years, and only a fraction of that increase can have come from natural forces.
2. PARIS GOALS – Almost all countries have signed up to the 2015 Paris climate accord, which aims to limit global warming to an increase of 2 degrees Celsius (3.6 Fahrenheit) above the pre-industrial average by the year 2100. The agreement says that ideally the increase would be no more than 1.5 degrees Celsius (2.7 degrees Fahrenheit).  But the report’s 200-plus authors looked at five scenarios and concluded that all will see the world cross the 1.5-degree threshold in the 2030s — sooner than in previous predictions. Three of those scenarios will also see temperatures rise 2 degrees Celsius.
3. DIRE CONSEQUENCES  – The 3,000-plus-page report concludes that ice melt and sea level rise are already accelerating. Wild weather events — from storms to heat waves — are also expected to worsen and become more frequent.  Further warming is “locked in” due to the greenhouse gases humans have already released into the atmosphere. That means even if emissions are drastically cut, some changes will be “irreversible” for centuries, the report said.
4. SOME HOPE – While many of the report’s predictions paint a grim picture of humans’ impact on the planet and the consequences that will have going forward, the IPCC also found that so-called tipping points, like catastrophic ice sheet collapses and the abrupt slowdown of ocean currents, are “low likelihood,” though they cannot be ruled out.
5. BIG CATCH – Although temperatures are expected to overshoot the 1.5-degree-Celsius target in the next decade, the report suggests that warming could be brought back down to this level through what are known as “negative emissions.” That means sucking more carbon dioxide out of the atmosphere than is added, effectively cooling the planet again. The panel said that could be done starting about halfway through this century but doesn’t explain how, and many scientists are skeptical it’s possible.

Sound Bites

• More than three decades ago, a collection of scientists assembled by the United Nations first warned that humans were fueling a dangerous greenhouse effect and that if the world didn’t act collectively and deliberately to slow Earth’s warming, there could be “profound consequences” for people and nature alike.    The scientists were right.
• The sprawling assessment, compiled by 234 authors relying on more than 14,000 studies from around the globe, bluntly lays out for policymakers and the public the most up-to-date understanding of the physical science on climate change.
• We’re out of time. It’s as simple as that.
• If the planet warms much more than 2 degrees Celsius above preindustrial levels — a scenario all but certain at the current pace of emissions — such change could trigger the inexorable collapse of the Greenland ice sheet and more than six feet of sea-level rise that could swamp coastal communities. Coral reefs would virtually disappear.
• The oceans will continue warming to 2100 and beyond, the authors write. Shrinking seasonal snow cover across the Northern Hemisphere is all but certain. The rate of sea-level rise is increasing and is destined to continue in coming decades. The likelihood and severity of extreme hot weather “will occur throughout the 21st century.”
• Climate scientists, who were once dedicated to avoiding hyperbolic statements so as not to “induce panic” have thrown caution to the wind and are now using words like “Code Red”, “inevitable”, and “irreversible” replacing words like “unprecedented” or “potential” or “likely”.
• Kos.  Deciphering the IPCC 2021 Climate Change Report and its message. We must act now, or else …
  Here we provide a quick summary of the report and point out a few important findings that can be used to educate those among our friends and family who do not understand climate science or are active climate change deniers.

Bloomberg Green

Today, the United Nations Intergovernmental Panel on Climate Change delivered its latest comprehensive report on the state of global climate science—just the sixth in the body’s more than 30-year history. The report’s 200-plus authors distilled 14,000 papers to produce today’s release. Even the so-called “summary for policymakers,” a distillation of the report’s key findings approved by the delegations of 195 nations, clocks in at 42 pages. If you’re here, then you want to know more about climate change and how to respond to it. Still, almost nobody wants to have to sift through that much scientific jargon—instead, let us do that for you. Here are five key takeaways from the IPCC report: 1. The last decade was hotter than any period in 125,000 years. Not only that but atmospheric CO₂ is now at a two million-year peak. Consuming fossil fuels has combined with agriculture to push methane and nitrous oxide—also greenhouse gases—to records for at least the last 800,000 years. All the greenhouse gases have elevated the global average temperature by about 1.1° Celsius above the late 19th century average. In fact, humans have already dumped enough greenhouse gas into the atmosphere to heat up the planet by 1.5°C—one of the goals set by the Paris Agreement—but fine-particle pollution from fossil fuels is masking it by providing a cooling effect. The combined contribution to global warming of natural factors, such as the sun and volcanoes, is now estimated to be close to zero. 2. Scientists can now link specific weather events to human-made climate change. This hasn’t always been the case. A recently as 20 years ago, for instance, it was virtually impossible to attribute any particular storm or temperature spike to the warming world. But the climate science profession has seen entire specialties emerge and mature since the IPCC’s previous mega-report in 2013. No field is more resonant than the ability to analyze extreme weather events in real-time to determine what role climate change is playing. The deadly heat wave that gripped the western coast of North America in June had detectable evidence of human responsibility—and that determination came quickly. World Weather Attribution, an international research group, needed just days after the heat broke to conclude that the extraordinary temperatures would be “virtually impossible” without climate change. 3. Scientists have narrowed the estimated range for how temperatures respond to greenhouse-gas emissions. This one is a milestone in the field of climate sensitivity that’s taken four decades. Drawing from research on ancient climates, as well as advanced satellite technology that monitors clouds and emissions, new models have narrowed the projections of the atmosphere’s likely response to industrial emissions. That allowed the IPCC authors to focus their temperature projections for the rest of the century, giving humanity a clearer picture of what may lie in store if we don’t act quickly to curtail emissions. The Earth’s response to a theoretical doubling of preindustrial CO₂ levels is now thought to be between 2.5°C to 4°C—a much smaller range than 1.5°C to 4.5°C in previous IPCC reports. These findings rule out the possibility that unrestricted emissions will have only a mild effect on global temperatures, a hope very few observers of events in recent months could cling to. But the narrower range also provides powerful evidence of the world’s best pathway to safety: swiftly ending the release of carbon dioxide and other greenhouse gases. 4. The Earth rewards good behavior. Almost as soon as emissions cease, heating will cease and temperatures will stabilize in a couple of decades. But some effects—such as sea-level rise—will remain irreversible for centuries. It’s a race between the avoidable and unavoidable, and humanity is behind. Scientists broke new ground in this IPCC report by projecting what happens when our emissions get to zero. As the world reduces its use of fossil fuels, for instance, the cooling effect of aerosols will start to decline. The scientists are confident that one way to counter that decline would be to pursue “strong, rapid and sustained reductions” in methane emissions. Beyond CO₂, methane, and nitrous oxide, there are four other greenhouse gases that also provide opportunities to slow warming. 5. The IPCC’s volunteer scientists build consensus with all UN governments before releasing this report. Sometimes it’s a fight. But unanimous agreement among the nations of the world, who all must affirm that the findings are summarized accurately, is a very powerful tool. It’s what makes the IPCC the most authoritative body on global warming. The new report begins with a definitive statement: “It is unequivocal that human influence has warmed the atmosphere, ocean and land.” Tom Evans, climate diplomacy researcher at the think tank E3G, put the implication succinctly: “No government has any excuse to duck their responsibility to act.” You can read more about the report on Bloomberg Green. — With Akshat Rathi