John Kerry had been speaking for nearly an hour but felt obliged to get something else off his chest.

My interview last week with the former secretary of state at the Free Library of Philadelphia was winding down when I raised a question I have sometimes put to others whose books are widely reviewed. Where websites now routinely mine new releases for those revelatory nuggets they can trumpet, I wondered what Kerry thought he had revealed that had been overlooked?

He paused, and then said with a laugh, "It's the perfect question to ask, and the perfect one for the author to find a way to evade."

After gathering his thoughts, he offered a litany of subjects he said he'd candidly discussed in the memoir, Every Day Is Extra, including: his faith, divorce, Senate service, and presidential run.

He calls it  "an honest, no-holds-barred lay-down of both personal things as well as public things that we need to think about."

But then, sensing this was my final question, he volunteered an additional thought.

"May I take the liberty of saying something that's really important?"

Kerry then spent 10 minutes calling attention to the final chapter of the book, titled "Protecting the Planet." This section is his account of the Paris Agreement as well as his recounting of going to the Arctic with the foreign minister of Norway.  Coincidentally, having voted absentee in the 2016 election, Kerry was traveling from New Zealand to Antarctica as Donald Trump was being elected.  ("The whole plane almost voted to stay in Antarctica after they got the news," he quipped.)

"What I learned in Antarctica about the West Antarctica ice sheet, 3½-miles-deep ice and the fragility now that they're noticing, the fissures  in the ice, the breakoff of the Larsen ice sheet that floats out and melts, it's larger than the size of the state of Rhode Island. … And, folks, I just, I've pledged to myself that I'm not going to anywhere without trying to sound the alarm bell and summon us to the mission of doing something more than we are doing today.

"I negotiated the Paris Agreement on behalf of our nation. I was privileged to sign it at the United Nations. You may see that picture with my granddaughter on my lap.  This is existential — I don't know how to say it more.  We just had three storms last year, Harvey, Irma, and Maria.  Harvey dumped as much water in five days on Houston as goes over Niagara Falls in a year.  Irma had the first recorded sustained winds of 185 miles an hour for 24 hours.  And you saw what Maria did to Puerto Rico.  It cost you $265 billion to clean up after those three storms.  That's one-third  the budget of the Defense Department.  That's more money than eight departments of our government, including Education and Commerce Department put together.  And yet we can't find the $100 billion that has to go into the Green Climate Fund to help less developed nations be able to adapt or mitigate or prevent the worst effects of climate change."

Kerry noted that the goal in Paris was to hold the Earth's temperature increase to what scientists were saying was a tipping point of calamity, 2 degrees Centigrade.

"We had an aspirational goal of 1.5 degrees because the Pacific Island states were clamoring that 2 degrees was too much.  We're at 1 degree now, a 1-degree increase already."

Three days after he spoke those words, the U.N.'s Intergovernmental Panel on Climate Change (IPCC) issued a new report in South Korea revealing that the consequences of climate change are even more dire and immediate than previously believed.

The authors of the IPCC report found that where the planet has already warmed 1 degree Celsius (1.8 degrees Fahrenheit) since the Industrial Revolution, if greenhouse-gas emissions continue at the current rate, that number will increase to as much as 1.5 degrees Celsius, or 2.7 degrees Fahrenheit during the lifetime of many who now inhabit the planet.

The report reads: "Human activities are estimated to have caused approximately 1.0°C of global warming above pre-industrial levels, with a likely range of 0.8°C to 1.2°C. Global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate."

Wait: I hope to be around in 2030, at which point I would be 68; in 2052 I'll be 90. In other words, climate change is no longer something our children's grandchildren will have to deal with.  It is unfolding on our watch.  This point was made clear to me in an analysis conducted for the New York Times by the Climate Impact Lab, a group of climate scientists, economists, and data analysts from the Rhodium Group, the University of Chicago, Rutgers University, and the University of California, Berkeley.

When I was born in Doylestown in 1962, the area could expect to see 16 days per year reach at least 90 degrees.  Today, that community experiences an average of 20 or more days at 90 degrees or above.  By the time I'm 80, there could be 35 of these very hot days.  The likely range is between 24 and 39.

According to the Climate Impact Lab, "The Doylestown area is likely to feel this extra heat even if countries take action to lower their greenhouse gas emissions by the end of the century.  If countries continue emitting at historically high rates, the future could look even hotter. The future projection shown here assumes countries will curb emissions roughly in line with the world's original Paris Agreement pledges (although most countries do not appear on track to meet those pledges)."

Meanwhile, the Trump administration responded to the U.N. report with silence, even as Hurricane Michael was about to make landfall on the Gulf Coast.