Aug 11, 2021
Today's GIF
It's a little 1980s-ish, but if the guy can do this shit when he's 78 years old, I'm OK with it.
Today's Tweet
Today's TikTok actually, but hey
Watch all of this.pic.twitter.com/ruwjQjHt0V
— Brian Tyler Cohen (@briantylercohen) August 11, 2021
COVID-19 Update
Yesterday, August 10th, 2021
10,103 people were killed by COVID-19
99.99 % of them were not fully vaccinated
World
New Cases: 610,169 (⬆︎ 30%)
New Deaths: 10,103 (⬆︎ .23%)
USA
New Cases: 124,205* (⬆︎ .34%)
New Deaths: 775* (⬆︎ .12%)
*FL, NE, MI, IA, KS, SD posted no numbers yesterday, so I've added their combined 7-day Rolling Averages (about 23,000 Cases & 115 Deaths per day).
USA Vaccination Scorecard
Total Vaccinations: 195.6 million (58.9%)
Fully Vaccinated: 166.9 million (50.3%)
And BTW, if the Delta Wave continues at this pace, we should be over 700,000 dead Americans by Thanksgiving. Happy Holidays.
‘Goldilocks virus’: Delta vanquishes all variant rivals as scientists race to understand its tricks
The variant battle in the United States is over. Delta won.
Since late last year, the country has been overrun by a succession of coronavirus variants, each with its own suite of mutations conferring slightly different viral traits. For much of this year, the alpha variant — officially known as B.1.1.7 and first seen in the United Kingdom — looked like the clear winner, accounting for the majority of cases by April. In second place was iota, B.1.526, first seen in New York City. A few others made the rogue’s gallery of variants: gamma, beta, epsilon.
Then came delta — B.1.617.2. It had spread rapidly in India, but in the United States, it sat there for months, doing little as the alpha advanced. As recently as May 8, delta caused only about 1 percent of new infections nationally.
Today, it has nearly wiped out all of its rivals. The coronavirus pandemic in America has become a delta pandemic. By the end of July, it accounted for 93.4 percent of new infections, according to the Centers for Disease Control and Prevention.
The speed with which it dominated the pandemic has left scientists nervous about what the virus will do next. The variant battles of 2021 are part of a longer war, one that is far from over.
Delta is sending thousands of people into hospitals every day and has knocked the Biden administration back on its heels. In a few short weeks, the delta variant changed the calculations for what it will take to end the pandemic.
Epidemiologists had hoped getting 70 or 80 percent of the population vaccinated, in combination with immunity from natural infections, would bring the virus under control. But a more contagious virus means the vaccination target has to be much higher, perhaps in the range of 90 percent.
Globally, that could take years. In the United States, the target may be impossible to reach anytime soon given the hardened vaccine resistance in a sizable fraction of the country, the fact that children under 12 remain ineligible and the persistent circulation of disinformation about vaccines and the pandemic.
With so many people unvaccinated, in the United States and around the world, the virus has abundant opportunity not only to spread and sicken large numbers of people, but to mutate further. Some scientists have expressed hope that the virus has reached peak “fitness,” but there is no evidence this is so.
“To see delta just running laps around these other strains is very concerning,” said Benjamin Neuman, a virologist with Texas A&M University. “It’s like ‘Jurassic Park,’ the moment you realize the dinosaurs have all got loose again.”
Delta’s meteoric takeover of the pandemic in the United States brought a jarring, premature end to a summer of relative freedom from the global viral emergency. Just as schools and workplaces were ready to hit reset and embrace a level of normalcy, indoor mask-wearing is back in much of the country, regardless of vaccination status.
Hospitals in states with low vaccination rates are struggling to cope with a flood of patients. At the same time, vaccination rates are jumping as the reality of the pandemic and the efficacy of the vaccines overcome fear, inertia and disinformation.
A dangerous brew
Several factors have played a role in the rise of delta:
Behavior. This is almost impossible for researchers to quantify. As infection numbers started dropping in mid-April, people began returning to crowded gyms, restaurants, ballparks, indoor theaters, dance clubs. The CDC said vaccinated people didn’t need to wear masks. Human nature took over. Only the hypervigilant refused to behave as if the pandemic had ended.
Vaccine resistance. When the United States was reporting 3 million inoculations each day, it appeared plausible that by July 4 the Biden administration would reach its goal of 70 percent of adults with at least one shot. But in May, the rate of vaccination slowed dramatically. As of today, more than 90 million people nationwide who could get a shot haven’t. Tens of millions of children remain ineligible because the vaccines do not have approval for those age groups yet.
The delta variant itself. The rapid ascendancy to total domination is the real-world proof that this variant is different. For virologists studying the coronavirus up close, that difference remains somewhat mysterious. Scientists are racing to understand what makes this variant so successful. They are studying it in animal models and in petri dishes, and scrutinizing the genomes of thousands of closely related lineages.
What’s most sobering to scientists is how the coronavirus keeps getting better at jumping from person to person.
The original strain that emerged in Wuhan, China, had an estimated reproductive number — an “R-naught” — of roughly 2.5. That’s the average number of new infections generated by each infected person in a population without immunity or mitigations. Any number above 1 means that outbreaks will expand and spread. But the CDC and other scientists say delta has a reproductive number greater than 5.
The result is what the United States has endured this summer: viral explosion.
'Sicker quicker'
Although the greater transmissibility of delta is clear at this point, scientists are less certain about whether it has enhanced virulence — that is, whether it’s more likely to make a person severely ill. The evidence on disease severity is limited and largely anecdotal.
Stephen Brierre, chief of critical care at Baton Rouge General in Louisiana, said the onset of respiratory failure requiring ventilation seems to be more rapid: “This is observational and anecdotal at this point: They get sicker quicker.”
Emily L. Tull, a nurse practitioner in the covid unit at Willis-Knighton Medical Center in Shreveport, La., said she is encountering more renal failure, more liver damage and more blood clots in patients since delta took over. More patients are unable to get off ventilators, she said.
Under normal circumstances, one nurse manages two patients in intensive care. In recent weeks, Tull said, “these patients are so sick they’re requiring one-on-one care.”
Patients are younger compared with earlier in the pandemic, perhaps because fewer young people are vaccinated. Tull said health-care workers are “having to make the decision of do we start dialysis on a healthy 25-year-old?”
In Alabama, where about 43 percent of adults are fully vaccinated and virtually all 67 counties are reporting high levels of community transmission, health officials are seeing inpatient data supporting that “delta may be more harmful,” according to Jeanne Marrazzo, director of the infectious-diseases division at the University of Alabama at Birmingham School of Medicine.
At the 1,200-bed UAB hospital, patients hospitalized for covid-19 are younger, the patients who have died are younger, and there appears to be greater use of a last-resort treatment, called ECMO, that can mechanically substitute for badly damaged lungs. The heavy use of ECMO “connotes truly serious systemic illness,” Marrazzo wrote in an email.
An internal CDC document, first disclosed late last month by The Washington Post, cited several studies from other countries showing that infections with delta are more likely to result in hospitalization. The document concluded that greater disease severity is “likely” with delta — one reason the authors said the agency needed to “acknowledge the war has changed.”
CDC Director Rochelle Walensky said Thursday that such research is preliminary. She noted that the delta variant spread rapidly in a time when mitigation efforts such as masking and social distancing had been relaxed. That has led to many more people being exposed and made it difficult for researchers to disentangle the severity of the virus from important changes in how people are exposed to it.
A mystery story
At the CDC, the war has indeed changed. The agency has often acted at the pace of an academic institution. It can be glacial in putting out new guidance. Delta forced it to accelerate its normal process when evidence emerged that vaccinated people with breakthrough infections are spreading the virus. The agency changed its masking guidance without initially publishing the data that incited the change.
A “full-court press” to understand the delta variant is underway at the agency and will continue “until we break this surge,” said one official, who spoke on the condition of anonymity because he wasn’t authorized to speak publicly on the matter.
Vaccinations remain key. All three vaccines with emergency use authorization in the United States are highly effective at preventing severe illness or death from delta or other variants. Vaccinated people rarely need hospitalization for covid-19, the disease caused by the virus. Delta is spreading fastest in areas with low vaccination rates. Vaccination lowers the risk of infection eightfold and the risk of hospitalization or death 25-fold, according to the CDC.
But vaccinated people are getting sick, too. Delta appears to be slightly more capable than some other variants at causing breakthrough infections, which are usually mild to moderate cases that do not require hospitalization.
The rising number of breakthrough infections isn’t surprising: As the number of vaccinated people increases, and delta swarms the nation, it’s inevitable that the virus will sometimes sneak past the enormously robust shield of protection afforded by vaccines.
The recent Provincetown, Mass., outbreak that drew national attention illustrates the point. The people who flocked to the tourist town at the tip of Cape Cod were overwhelmingly vaccinated. Hundreds of people became infected, three-fourths of them with breakthrough cases. But the vaccines kept them from becoming severely ill: Only four people with breakthrough infections were hospitalized. What alarmed the CDC were tests showing that vaccinated people with delta infections had viral loads similar to those among unvaccinated people. That suggested vaccinated people could spread the virus.
There is limited data on how common breakthrough cases are. The CDC has published only its tally of breakthrough hospitalizations and deaths, not infections. Vaccinated people who have mild symptoms of covid-19 may think they have a summer cold and never get tested.
Walensky and Surgeon General Vivek H. Murthy have said in recent weeks that 97 percent of people hospitalized with covid-19 were unvaccinated. A document posted Aug. 2 by the White House stated, “Virtually all U.S. Hospitalizations and Deaths are Among Unvaccinated People.” The document cited that in Ohio, 99.5 percent of deaths and 98.8 percent of hospitalizations were among the unvaccinated.
But officials have relied on older data that does not capture the current impact of the delta, Walensky acknowledged Thursday when questioned at a White House covid-19 task force briefing.
The Ohio health department, contacted by The Post, confirmed the numbers for the state but noted that the data covers Jan. 1 to July 21. Walensky said she had been relying on data from January to June. The use of figures from early in the year skews the picture by including a large number of people sickened and killed by the virus before vaccinations were widely available.
Walensky said Thursday that her agency plans to update the breakthrough data.
The uncertainty about breakthrough infections “is disconcerting, and I think the reality is it’s humbling as a medical community,” said William G. Morice II, chair of the department of laboratory medicine and pathology at the Mayo Clinic.
“Even with the whole world being focused on covid, we still don’t truly understand the intricacies of the virus and its interplay with the immune system,” he said.
A numbers game
A Colorado county, perched on the western slopes of the Rocky Mountains, tells the story of delta’s swift spread.
In early May, five cases of the delta variant were reported in Mesa County. The extent of the threat was still emerging, but public health officials urged residents to get vaccinated. They noted that only 36 percent of people eligible for a shot had been fully vaccinated. In late May, the county announced the first pediatric death from covid-19 — a child infected with delta and too young for a vaccine.
In late June, the Country Jam music festival opened. Public health officials sent a bus to administer vaccines on-site, and used signs and messages on the Jumbotron to warn concertgoers about delta.
By early August, there were nearly 900 known cases of infection caused by the delta variant. Vaccines remained the best protection against severe illness, but about half of known cases were in fully vaccinated people.
The national numbers are similarly vertical. The seven-day rolling average of cases used by The Post showed about 13,000 new cases a day July 1. On Friday, that figure topped 100,000, and there is no sign of the curve flattening. Deaths are rising sharply as well: The daily average jumped from 209 on July 6 to 489 on Friday, a month later.
Because the delta variant replicates so well when it gets inside human cells, the infectious dose may be lower. Infected people may also begin shedding the virus sooner and in greater quantities. It’s a numbers game, and delta has numbers on its side. Rapid replication of the virus has probably shortened the period between a person getting infected and becoming infectious, to perhaps two or three days rather than five or six.
The flip side is that the delta surge is expected to peak faster. A more contagious virus finds susceptible people quickly and burns through that “fuel” faster. This may explain why the United Kingdom and India have both experienced surprisingly swift drop in cases after recent delta surges.
'Delta surprised me'
Human beings have never before seen viral evolution in such vivid scientific detail. Genomic sequencing technologies developed in recent years allow scientists to witness the evolution of a pandemic virus in real time, as one lineage evolves into another.
Scientists say the delta variant’s mutations look, at first glance, unremarkable compared with the mutations in variants it has outcompeted. It lacks some of the immunity-evading mutations seen in gamma and beta, for example.
But one mutation, P681R, may play an outsize role in boosting delta. The coronavirus requires two steps to get into the cell, akin to putting a key into a lock and turning it to open the door. Most of the mutations identified in the other “variants of concern” seem to improve the key’s fit to the lock, said Vineet D. Menachery, a scientist who studies coronaviruses at the University of Texas Medical Branch in Galveston. The P681R mutation seems to improve how the key is turned, making it better at getting into cells.
Most laboratory research has focused on the spike protein the virus uses to enter cells. But delta has mutations that affect other regions — and little is known about what they do.
Nevan Krogan, a senior investigator at the Gladstone Institute of Data Science and Biosciences, found this year that the highly contagious alpha variant may have derived some of its advantage from being able to suppress a person’s innate immune response. That’s the first line of defense against an infection. He and colleagues are exploring whether something similar helps delta.
“When these variants started, everybody was talking ‘spike, spike, spike,’ ” Krogan said. “Obviously, spike is involved in this, getting virus into cells more effectively . . . there’s other mutations that are somehow suppressing the immune response.”
Menachery said he regularly debates with people in his laboratory and other scientists about the evolutionary potential of the virus. He describes this coronavirus as a “Goldilocks virus” — many things have to be just right for it to remain successful. A mutation that helps the virus enter a cell, for example, might come with an Achilles’ heel, making it less stable.
That leaves the open question of whether delta is the fittest — that is, the worst — version of the virus, or whether it could acquire some new mutations that make it even more formidable.
“Nobody knows what tricks the virus has left,” said Jeremy Luban, a virologist at the University of Massachusetts Medical School. “It’s possible we’ve seen all of its chess moves, or its poker tricks, but it’s got a very big complicated genome and it probably still has some space to explore.”
Like everyone else, scientists are wondering when SARS-CoV-2’s contagiousness will peak.
“Delta surprised me,” said Trevor Bedford, an expert on viral evolution at the Fred Hutchinson Cancer Research Center. “This doesn’t happen with an influenza pandemic. It doesn’t happen with Ebola. It doesn’t happen with most other things.”
He knows it can’t keep evolving to become more transmissible forever. Eventually, the virus will hit a ceiling, he said.
“But it’s not exactly clear what that is.”
Aug 10, 2021
Today's Beau
Justin King - Beau Of The Fifth Column
People who thump their chests about how they won't toe the line complaining bitterly about a guy who won't toe their line.
Here's the Garth Brooks tune in case you're interested.
We Shall Be Free
COVID-19 Update
Yesterday, August 9th, 2021
8,047 people were killed by COVID-19
99.996% of them were not fully vaccinated
World
New Cases: 527,341 (⬆︎ .26%)
New Deaths: 8,047 (⬆︎ .19%)
USA
New Cases: 102,375 (⬆︎ .28%)
New Deaths: 326 (⬆︎ .05%)
USA Vaccination Scorecard
Total Vaccinations: 195.2 million (58.8%)
Fully Vaccinated: 166.7 million (50.2%)
I've decided to bail on my 50-year high school reunion scheduled for next month.
Maybe I'm just being paranoid, but I'm not going to risk adding to the problem.
And most of those people I don't care to reune with anyway, he said in his usual curmudgeonly manner.
Should you cancel travel plans because of the coronavirus’s delta variant? Ask these questions.
For a blissful few weeks this spring, a summer of semi-normal travel seemed not just possible, but almost certain. Flights were booked, hotel reservations were made and vacation time was requested as those with wanderlust or pent-up desire to see loved ones organized their long-awaited excursions.
But the hyper-transmissible delta variant of the coronavirus has now forced some would-be travelers to cancel trips and others to consider whether it’s safe to follow through with their plans. As hospitalizations surge across much of the country — mostly among the unvaccinated — Americans are trying to adapt on the fly.
Asking yourself a few questions can help you decide whether to keep your travel arrangements.
Is everyone in your group of travelers vaccinated? Is anyone immunocompromised?
If you haven’t gotten vaccinated against the coronavirus, you should strongly consider staying home, experts said. Travel is much safer if at least two weeks have passed since your last dose. But if you have a weakened immune system, you may want to reconsider traveling, even if you have been vaccinated.
“If they have issues with their immune system or are immunocompromised, I would say now is probably not a great time to travel, because there are so many things that are outside of your control,” said Nasia Safdar, medical director of infection control at the University of Wisconsin Hospital and Clinics.
The status of anyone you’re going to visit also matters. Safdar said she would wear a mask around immunocompromised family members or friends, even in private settings where everyone has been vaccinated.
For unvaccinated people who must travel, the Centers for Disease Control and Prevention suggests taking a coronavirus test one to three days beforehand, staying away from crowds and remaining masked. You should also take another virus test three to five days after returning and self-quarantine for seven days. Also, keep in mind that some countries or venues might require children who are too young for vaccination to test negative for the virus.
How do you plan to travel?
To avoid contracting or transmitting the virus, the fewer fellow travelers you come into contact with, the better. For that reason, traveling by car is generally safer than taking a train, bus or airplane. Try to make as few stops as possible, because rest stops and gas stations will probably put you in proximity to many other travelers.
If you travel by air, you have a particularly high likelihood of ending up in a crowd. Although the virus doesn’t seem to spread easily on flights, you’ll probably be among hundreds or thousands of other passengers at an airport terminal or while in line for a security check.
How to cancel your flights, Airbnbs and more because of the delta variant
Remember that face masks are required on all public transportation and at transportation hubs such as airports. You should make sure the mask you bring meets your airline’s requirements, said Alvin Tran, an assistant professor of public health at the University of New Haven’s School of Health Sciences. Bandannas, scarves, balaclavas and face shields are often considered insufficient.
Before boarding an international flight, you may have to take a coronavirus test at your own expense and show proof of a negative result, said Lin Chen, director of the Travel Medicine Center at Mount Auburn Hospital in Cambridge, Mass.
Masks and covid-19: Explaining the latest guidance from the CDC and other experts
What’s the transmission rate at your destination?
The CDC maintains a map showing which regions of the United States have low, moderate, substantial and high rates of virus transmission at a given time. A separate guide tracks coronavirus prevalence in various countries and offers recommendations associated with each level of transmission. Travelers should avoid visiting areas with a “very high” degree of transmission, per the CDC’s guidelines.
Although it can be helpful to consult that data, Safdar suggested keeping in mind that regions can move quickly from one transmission category to another. So what looks like a low-risk destination when you’re planning may not be quite as safe by the time you arrive. For example, on Aug. 2, the CDC and the State Department added 16 destinations — including Ireland, Greece and the U.S. Virgin Islands — to their highest travel advisory category for the coronavirus.
A region’s immunization rate and the status of its hospitals also matter. There is probably more virus circulating in low-vaccination areas, and overwhelmed hospitals may mean you’ll have less access to medical care if you get sick or injured — with covid-19 or any other malady.
Chen said to also consider how you would manage if you tested positive for the coronavirus while at your destination. You should be prepared to self-quarantine there until you’ve recovered.
What travel restrictions are in place where you’re going?
Although some destinations are loosening restrictions to encourage visitors, others are tightening them in response to the delta variant. On Aug. 3, Israel said it would require visitors from the United States and 17 other countries to quarantine upon arrival, regardless of their vaccination status. Grenada now requires full vaccination for entry. Australia’s most populous city, Sydney, has been locked down for weeks.
On Aug. 9, the CDC added countries to its list of Level 4 — or very high — travel risk. France, Iceland, Israel and Thailand are included in the countries that the agency urges people to avoid.
Some countries, including France and Italy, are beginning to require proof of inoculation, documentation of immunity or a recent negative coronavirus test for entry to certain establishments. Chen cautioned that some foreign venues may not accept a CDC vaccination card as proof of immunization.
In the United States, many restaurants and bars also have said they’ll require vaccination. If you haven’t gotten your shots, consider whether the rules of the businesses you want to visit would prohibit you from going.
What you need to know about the highly contagious delta variant
Will you spend most of your trip indoors or outdoors?
It has been clear for months that the coronavirus spreads more easily inside than outside, so where you’ll be spending most of your trip should be a consideration in whether to go through with it. Hiking in a national park, for example, is low on the spectrum of risk. But Tran cautioned that he would still wear a mask while in line for an outdoor attraction, where social distancing is difficult.
If you’ll mostly be visiting museums, historic buildings and shops, on the other hand, you should consider the fact that the CDC is urging indoor mask-wearing in areas with substantial or high coronavirus transmission. And some jurisdictions, such as Nevada, D.C., Los Angeles County, St. Louis and others, are issuing mask mandates for indoor public spaces on their own. So, depending on your destination, you may need to wear a face covering for hours at a time. Jurisdictions may also have rules regarding social distancing and the hours that different types of venues can be open.
If you’re partaking in indoor activities, Safdar suggested keeping a low threshold for donning a face covering. And she said she would avoid indoor dining at any destination.
Can you get your money back if your travel plans change?
Your calculus for determining whether to go on a planned trip may depend in part on whether you can reschedule or cancel without losing money. Most travel insurance will reimburse you if you get the coronavirus before or during a trip but won’t help if you want to cancel out of nervousness about the delta surge, Megan Moncrief, a spokeswoman for travel insurance comparison site Squaremouth, previously told The Washington Post. She said you’d have to buy pricier “Cancel for Any Reason” coverage to account for that scenario.
What you should know about indoor dining amid the delta variant
How much risk and inconvenience are you willing to endure?
In this pandemic, there’s no such thing as a trip with zero chance of contracting the coronavirus. Whether it’s worth it to travel depends largely on your comfort level with risk. In a high-transmission area, Safdar said, it will be very hard to avoid the virus entirely.
Traveling right now also requires more preparation than usual. You’ll have to stay on top of evolving requirements and restrictions, even while at your destination, and adapt accordingly. You also may need to budget extra time and money to compensate. If you can afford to do so, working with a reputable travel agency can help you work through those challenges, Chen said.
“If somebody is prepared to face all those additional challenges, they might be okay and want to go anyway,” she said. “But I think for a lot of people, it might not be worth all the extra efforts.”
PLEASE NOTE: Potential travelers should take local and national public health directives regarding the pandemic into consideration before planning any trips. Travel health notice information can be found on the Centers for Disease Control and Prevention’s interactive map showing travel recommendations by destination and the CDC’s travel health notice webpage.
Aug 9, 2021
It's The Climate Change, Stoopid
I know, I know - one thing at a time. We have a problem with maintaining American democracy - without that, we have no hope of doing anything else.
I wish we had the luxury of one thing at a time. We don't.
Here's the really shitty thought about all that: Sociologists and Political Science nerds have shown how Climate Change drives us towards authoritarian rule (in times of crisis, people want action at the expense of process). The people in charge of our economy are largely unwilling to do anything to arrest our nearly headlong rush into environmental catastrophe, because they're the ones who benefit most from a top-down authoritarian system.
Plutocracy, thy name is Republican.
We'll have to do both. We have to understand that without Democrats in office, we stand almost no chance at all to make the changes we have to make in order to have a shot at avoiding the worst of a climate disaster we're already living in right now.
Key Findings You MUST Know From Just-Released IPCC Climate Change Report
The UN Intergovernmental Panel on Climate Change's first major scientific assessment since 2014, released Monday, shows unequivocally that global warming is unfolding more quickly than feared and that humanity is almost entirely to blame.
Here is a rundown of some of its key findings from the IPCC Working Group 1 report on physical science:
Goodbye 1.5 °C, hello overshoot
Earth's average surface temperature is projected to hit 1.5 or 1.6 degrees Celsius above preindustrial levels around 2030 in all five of the greenhouse gas emissions scenarios - ranging from highly optimistic to reckless - considered by the report. That's a full decade earlier than the IPCC predicted just three years ago.
By mid-century, the 1.5 °C threshold will have been breached across the board, by a tenth of a degree along the most ambitious pathway, and by nearly a full degree at the opposite extreme.
There is a silver lining: in the most ambitious if-we-do-everything-right scenario, global temperatures - after "overshooting" the 1.5 °C target - fall back to 1.4 °C by 2100.
Natural climate allies weakening
Since about 1960, forests, soil and oceans have absorbed 56 percent of all the CO2 humanity has chucked into the atmosphere - even as those emissions have increased by half. Without nature's help, Earth would already be a much hotter and less hospitable place.
But these allies in our fight against global heating - known in this role as carbon sinks - are showing signs of becoming saturated, and the percentage of human-induced carbon they soak up is likely to decline as the century unfolds.
Yes, climate change is to blame
The report highlights the stunning progress of a new field, attribution science, in quantifying the extent to which human-induced global heating increases the intensity and/or likelihood of a specific extreme weather event such as a heatwave, a hurricane or a wildfire.
Within weeks, for example, scientists established that the record-shattering heatwave that devastated British Columbia in June would have been "virtually impossible" without the influence of climate change.
More generally, the 2021 IPCC report includes many more findings reached with "high confidence" than before.
Sea rising higher, more quickly
Global oceans have risen about 20 centimetres (eight inches) since 1900, and the rate of increase has nearly tripled in the last decade. Crumbling and melting ice sheets atop Antarctica and especially Greenland have replaced glacier melt as the main driver.
If global warming is capped at 2 °C, the ocean watermark will go up about half a metre over the 21st century. It will continue rising to nearly two metres by 2300 - twice the amount predicted by the IPCC in 2019.
Because of uncertainty over ice sheets, scientists cannot rule out a total rise of two metres by 2100 in a worst-case emissions scenario.
Dire warnings from the deep past
Major advances in paleoclimatology - the science of natural climate in Earth's past - have delivered sobering warnings.
For example, the last time the planet's atmosphere was as warm as today, about 125,000 years ago, global sea levels were likely 5-10 meters higher - a level that would put many major coastal cities under water.
Three million years ago, when atmospheric CO2 concentrations matched today's levels and temperatures were 2.5 C to 4 °C higher, sea levels were up to 25 metres higher.
Methane in the spotlight
The report includes more data than ever before on methane (CH4), the second most important greenhouse gas after CO2, and warns that failure to curb emissions could undermine Paris Agreement goals.
Human-induced sources are roughly divided between leaks from natural gas production, coal mining and landfills on one side, and livestock and manure handling on the other.
CH4 lingers in the atmosphere only a fraction as long as CO2, but is far more efficient at trapping heat. CH4 levels are their highest in at least 800,000 years.
The report includes more data than ever before on methane (CH4), the second most important greenhouse gas after CO2, and warns that failure to curb emissions could undermine Paris Agreement goals.
Human-induced sources are roughly divided between leaks from natural gas production, coal mining and landfills on one side, and livestock and manure handling on the other.
CH4 lingers in the atmosphere only a fraction as long as CO2, but is far more efficient at trapping heat. CH4 levels are their highest in at least 800,000 years.
A focus on regional differences
Although all parts of the planet - from the oceans to the land to the air we breathe - are warming, some areas are heating faster than others. In the Arctic, for example, the average temperature of the coldest days is projected to increase at about triple the rate of global warming across the planet as a whole.
Sea levels are rising everywhere, but will likely increase up to 20 percent above the global average along many coastlines.
Although all parts of the planet - from the oceans to the land to the air we breathe - are warming, some areas are heating faster than others. In the Arctic, for example, the average temperature of the coldest days is projected to increase at about triple the rate of global warming across the planet as a whole.
Sea levels are rising everywhere, but will likely increase up to 20 percent above the global average along many coastlines.
Tipping points = abrupt change
The IPCC warns against abrupt, "low likelihood, high impact" shifts in the climate system that, when irreversible, are called tipping points. Disintegrating ice sheets holding enough water to raise seas a dozen metres; the melting of permafrost laden with billions of tons of carbon; the transition of the Amazon from tropical forest to savannah - are all examples.
"Abrupt responses and tipping points of the climate system... cannot be ruled out," the report says.
Global ocean 'conveyor belt'
The Atlantic Meridional Overturning Circulation (AMOC) - a large system of ocean currents that regulates the global transfer of heat from the tropics into the northern hemisphere - is slowing down, a trend "very likely" to continue throughout the 21st century.
Scientists have only "medium confidence" that the AMOC will not stall altogether, as it has in the past. If it did, European winters would become much harsher, monsoon seasons would likely be disrupted, and sea levels in the north Atlantic basin could rise substantially.
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