The U.N. Intergovernmental Panel on Climate Change has issued its gravest warning yet, saying major, irreversible climate catastrophe is unavoidable and that the world has a narrowing window to make drastic changes to prevent even greater devastation. That’s according to the IPCC’s first climate assessment in eight years, which shows the world is on track to surpass an average temperature rise of 1.5 degrees Celsius above preindustrial levels, failing to meet the goals of the Paris Climate Agreement. Even if the goal is met, the world will still have to contend with fast-melting Arctic ice, sea level rise and the warming and acidification of oceans — all of which contribute to more extreme weather events, including droughts, floods, wildfires and deadly heat waves. The IPCC does not offer recommendations to governments, but the U.N. says countries need to immediately move away from fossil fuels and to stop adding carbon to the atmosphere by 2050 in order to slow or halt the most catastrophic outcomes.

In Northern California, the Dixie Fire exploded in size over the weekend to become the largest single fire in California history — with a half-million acres burned. On Saturday, California Governor Gavin Newsom toured Greenville, a Gold Rush-era town north of Sacramento, its downtown almost completely destroyed by the Dixie Fire.

Gov. Gavin Newsom: “The extreme weather conditions, extreme droughts are leading to extreme conditions and wildfire challenges the likes of which we’ve never seen in our history. And as a consequence, we need to acknowledge, just straight up, these are climate-induced wildfires.”

There are 11 major wildfires now raging across California, and over 100 fires across 15 states — with more than 2 million acres burned. On Saturday, Denver, Colorado, experienced the poorest air quality of any big city in the world as smoke from western fires filled the sky with a thick, yellow-brown haze.

Meanwhile, fires continue to rage across Southern Europe, which is in a protracted heat wave. In Greece, thousands of people fled their homes on the island of Evia, some of them escaping aboard Coast Guard ships, as a massive wildfire turned the night sky red.

Vasilikia: “I am very angry. Most people here are very angry. The disaster, you can see it, right? It’s huge. Our villages are destroyed. There is nothing left from our homes, our properties. Nothing. Nothing.”

In Afghanistan, the Taliban has seized control of five cities since Friday as they continue their relentless offensive. Kunduz, Sar-i-Pul and Taloqan were the latest provincial capitals to fall to the Taliban on Sunday, as the militant group also makes advances in the major cities of Kandahar and Lashkar Gah. The Biden administration reportedly has no plans to change its deadline of August 31 to complete the U.S. withdrawal, though it previously did not rule out continuing airstrikes beyond that date. On Friday, Taliban fighters assassinated the government’s top media and information official in Kabul. Meanwhile, the U.N. special envoy for Afghanistan said there were more than 1,000 civilian casualties over the past month and that the war has now entered a “deadlier and more destructive phase.”

Deborah Lyons: “This is now a different kind of war, reminiscent of Syria recently or Sarajevo in the not-so-distant past. To attack urban areas is to knowingly inflict enormous harm and cause massive civilian casualties.”

At least 244,000 people in Afghanistan have also been internally displaced since the Taliban offensive started in May.

As the U.S. is once again averaging over 100,000 new daily COVID-19 cases due to the Delta variant-driven surge, top White House adviser Dr. Anthony Fauci warned of future variants that could emerge unless more people get vaccinated.

Dr. Anthony Fauci: “If you give the virus a chance to continue to change, you’re leading to a vulnerability that we might get a worse variant. And then, that will impact not only the unvaccinated; that will impact the vaccinated, because that variant could evade the protection of the vaccine.”

Though vaccine demand has increased in areas hit hard by Delta surges, health systems in some states say they are already overwhelmed. In Austin, Texas, officials activated the emergency text alert system to warn residents the situation is “dire” and healthcare resources are limited. This comes as Governor Greg Abbott is fighting statewide mitigation efforts.

In Florida, which accounts for nearly a quarter of cases nationwide, conservative radio host and anti-vaccine propagandist Dick Farrel has died of COVID-19. Before dying, he urged his friends to get vaccinated. Republican Governor Ron DeSantis has banned mask mandates and has threatened to withhold funds from school districts that defy the ban.

In a reversal, Randi Weingarten, president of the American Federation of Teachers, said she supports requiring vaccines for teachers. The AFT is meeting this week to consider issuing the mandate. Dr. Fauci recently said he expects a “flood” of vaccine mandates at businesses and schools as soon as the shots receive full FDA approval.

The Biden administration extended the pandemic-related freeze on federal student loan repayments through January 2022. It was set to expire at the end of September. Some Democrats renewed calls on Biden to use executive authority to cancel $50,000 of individual student debt.

On Capitol Hill, senators voted Sunday evening to end debate over a $1.2 trillion infrastructure package, clearing the way for a final vote early this week. The bipartisan bill would see the largest-ever federal investments in public transit, clean water and green energy. But critics say it’s far short of what’s needed to tackle the climate crisis. The package is barely half of what President Biden proposed — and far short of the $10 trillion THRIVE Act favored by progressives. Senate Democrats are expected to turn to a $3.5 trillion budget resolution that could pass without Republican support, covering additional infrastructure needs.

Democrats in the Texas House of Representatives refused to return to the state Capitol in Austin Saturday, denying a quorum to Republicans who hoped to pass draconian voter suppression bills in a special legislative session. It was the third time Democrats have blocked Republican Governor Greg Abbott’s attempts to pass new election laws — following their flight to Washington, D.C., last month.

CBS News reports at least three dozen holding facilities for unaccompanied migrant children may lose their state licenses next month but will likely continue to operate without being subject to inspections or state oversight. Republican Governor Greg Abbott ordered state officials in May to stop issuing licenses to facilities for migrant children.

In more immigration news, the Biden administration has begun flying deported Central American asylum seekers into Mexico instead of their home countries as an attempt to deter them from seeking refuge at the U.S.-Mexico border.

Spanish humanitarian aid workers are reporting at least 42 refugees — including eight children — are feared dead after their boat capsized off the coast of Western Sahara last week. Only 10 people survived. So far this year, over 1,100 refugees have perished crossing through dangerous sea routes as they attempted to reach Europe.

In related news, a ship carrying at least 257 refugees has docked in the Italian port of Trapani — a week after the German humanitarian aid organization Sea Watch rescued the refugees off the coast of Tunisia.

In Argentina, tens of thousands of people held demonstrations in Buenos Aires and throughout the country this weekend as anger mounted over skyrocketing unemployment and a worsening economic crisis triggered by the pandemic. This is a protester in Buenos Aires.

Néstor Pluis: “My brother is unemployed. Many of my neighbors are without a job. We see a lot of people are suffering around the country due to a lack of work. Politicians should get their act together. People are tired of lies.”

In Thailand, protesters took to the streets of Bangkok Saturday demanding the resignation of Prime Minister Prayuth Chan-ocha and denouncing the government’s mishandling of the pandemic and economic crisis. Police assaulted protesters with tear gas and rubber bullets. It was the latest in a series of anti-government and anti-monarchy demonstrations demanding democratic reforms. This comes as Thailand reported nearly 22,000 new COVID-19 cases Saturday and at least 212 deaths, both new records.

Former acting Attorney General Jeffrey Rosen has testified that one of his deputies tried to help Donald Trump subvert the results of the 2020 election in the waning days of his presidency. That’s according to The New York Times, which reports Rosen testified to Justice Department and Senate investigators over the weekend that his deputy, Jeffrey Clark, pressured Justice Department officials to publicly assert false claims about election fraud in order to cast doubt on the Electoral College results. Clark’s promotion of conspiracy theories was reportedly welcomed by Trump, who considered replacing Rosen with Clark as acting attorney general.

A woman who last week filed a criminal complaint against New York Governor Andrew Cuomo for sexual misconduct has come forward to share her story. Brittany Commisso, who appeared as “executive assistant 1” in the New York attorney general’s report on Cuomo, said the governor groped her, kissed her against her will and verbally harassed her. Commisso spoke to CBS News’s Jericka Duncan.

Jericka Duncan: “Why did you file that criminal complaint with the sheriff’s office?”

Brittany Commisso: “It was the right thing to do. The governor needs to be held accountable.”

Jericka Duncan: “And just so I’m clear, again, being held accountable, to you, means seeing the governor charged with a crime?”

Brittany Commisso: “What he did to me was a crime. He broke the law.”

The New York State Judiciary Committee is meeting this morning to discuss potential impeachment proceedings. Meanwhile, Cuomo’s top aide and fierce defender, Melissa DeRosa, resigned Sunday amid the mounting scandal.

Today marks 76 years since the U.S. dropped an atomic bomb on the Japanese city of Nagasaki, killing 74,000 people, just three days after the U.S. dropped the world’s first atomic bomb in Hiroshima, killing some 140,000 people. The Treaty on the Prohibition of Nuclear Weapons came into force earlier this year, but neither Japan nor the United States have signed it.