Earlier this year, scientists warned that the Great Barrier Reef could be on the brink of its most widespread bleaching event ever recorded. That fear has now been realized.

New surveys conducted by scientists at Australia’s James Cook University and the Great Barrier Reef Marine Park Authority show that a summer of extreme heat has caused the reef, which is a World Heritage Site, to suffer a mass bleaching of unprecedented scale. Corals from the far north to the southern tip of the 1,400 mile-long ecosystem are experiencing severe impacts.

It was also one of the reef’s worst mass bleaching episodes in terms of intensity, second only to 2016, which killed half of all shallow-water corals on the northern Great Barrier Reef.

And unlike the summer of 2016, when an intense marine heat wave coincided with one of the strongest El Niño events on record, this past summer brought a bleaching event without any assistance from the Pacific climate oscillation.

El Niño events can elevate ocean temperatures in that part of the world, making bleaching events more likely. To scientists, this is another clear sign that human-caused climate change is now the primary driver behind these devastating events.

Mark Eakin, coordinator for the National Oceanic and Atmospheric Administration’s Coral Reef Watch program, described the rate of recurrence of these events as “truly disturbing.” Bleaching from the 2016 event was followed by a recurrence in 2017, when there was also an absence of an El Niño.

“In 2016 and 2017, the Great Barrier Reef had their first back-to-back bleaching events. Now we have the third bleaching event in five years,” Eakin wrote in an email.

“That is unprecedented on the Great Barrier Reef.”

Heat stress can be deadly to corals. Bleaching is a response to heat stress that occurs when corals spend too much time in water that’s too hot for them to handle. Exposure to prolonged heat causes the reef-building animals to temporarily evict their zooxanthellae, symbiotic algae in which the corals shelter in exchange for food.

Six volunteer firefighters use machetes to cut a path through the vines and underbrush of the Chiquitano forest in Bolivia's eastern lowlands. They're approaching the leading edge of a fire that's been burning for hours.

They attempt to smother it with shovelfuls of dirt and water they carry on their backs in tanks normally used to fumigate crops. But the smoke is getting thicker, the heat stronger and swirling winds push the flames forward. Realizing they are overmatched, José Zapata, the only trained firefighter among the group, orders his men to pull out.

"The fire was coming from many sides," Zapata explains as he leads a hasty retreat to the relative safety of a nearby road. "We could have gotten trapped."

Bolivian firefighters, army troops and volunteers have been working nonstop for the past two months amid some of the worst fires in the country's recent history. President Evo Morales, who is running for reelection next month, has suspended his campaign to deal with the expanding disaster.

On Saturday, regional officials estimated nearly 6 million acres of forest and savanna have been torched since August. Eduardo Forno, who heads the Bolivian chapter of Conservation International, says that is almost equal to the area burned this year in the Amazon rainforest in neighboring Brazil, a country eight times larger.

It is the riddle wrapped in mystery inside an enigma for all who lean left: how is it possible that Donald Trump’s sins, deceits, criminal acts, vile behaviors, racist bloviation, misogynist bile, xenophobic rants, impeachable offenses, and now broadside volleys against the Constitution have had, in aggregate, no discernible impact on his approval rating?

Theories abound. Some involve arrogant estimates about the IQs and education of Trump supporters, but a modest amount of googling can shoot these theories to pieces. There is the theory that many Trump supporters care only about the strong state of the economy and stock market. Other theories hold that Trump gives voice to the anger of Americans who feel that their government has failed them.

But there is of course another factor, and it is profound. And that is the fact that millions of perfectly intelligent Americans choose to get their news from Fox News, and each and every day they are provided an aggressively curated version of the day’s events. If you want to know a want to know a big reason why Donald Trump’s approval rating is immutable, the answer lies there...

All of which brings me to a recent flash of brilliance from contrarian Bernie Sanders.

Sure, we can worry that Bernie's ideological rigidity and uncompromising rhetoric could lead to damaging rifts in the Democratic Party. But it is fair to argue that he has been the pre-eminent thought leader for the Party over the past four years... creative, perceptive, original, and way out in front of the party's sharp shift to the left.

A few weeks ago Bernie participated in a town hall-style television event broadcast on Fox News. Bernie’s town hall in the other team’s town was particularly notable as the Democratic Party had recently announced that it would refuse to allow Fox News to host any of the televised debates in the Democratic primary season.

This time, it’s sure not crazy Bernie. Bernie is right and the Democratic Party leadership is crazy...

So Bernie Sanders decided to go behind enemy lines and speak directly to Trump's base. He realized that allowing the base to listen exclusively to Sean Hannity was to acquiesce to the polarization that fuels Trump's power.

If you don't shake the faith of Trump's base, he keeps his Senators, he keeps his job, and he keeps crushing the checks and balances that make our nation a democracy governed by the rule of law.

We must try to get to Trump's base.