Ever had a late lunch on a fine day with a foremost authority on energy — to discuss the nuclear industry and how nuke power plants might help mitigate climate change?

… And gone away dumbfounded, with a sinking sense of despair?

Well, I have, and I'll share some stuff worth sharing. Caution: You may not like how this ends.

Spend time with Dr. Dean Abrahamson, professor emeritus at the University of Minnesota's Humphrey Institute and ex-energy adviser to Sweden's prime minister, and you learn a lot about nuclear power — and a lot more about how alarming global warming has become.

For those who think nuclear power is among the top-tier responses to climate change, here's an invitation to think a bit deeper.

While there's innate fear of nuclear power, the technology that generates 20% of our nation's electricity has a pretty good safety record. Accidents do happen, of course, and we all know of three famous nuclear power disasters in the U.S., the former Soviet Union and Japan.

But to my mind, more immediate problems include where nukes are located and the storage of "spent fuel rods" (no longer useful in making steam to spin turbines).

Some plants, including Xcel's Monticello units and New York's Indian Point, are only a few miles upstream from major cities. The nation's largest nuke, Palo Verde, is upwind from metro Phoenix. Diablo Canyon sits atop a California earthquake zone.

Then there's the long-promised national radioactive waste storage site that was never built. So those spent fuel rods, which will be highly radioactive for thousands of years, are stored at plant sites — like the large and growing repository a short distance upstream from Minneapolis' water intake, where it will remain until God knows when.

I asked Abrahamson about nuclear power helping mitigate climate change, since those generators don't emit greenhouse gases like those powered by coal or natural gas.

Yes, nukes are carbon-free, he said, and could be built fairly quickly despite delays in planning and permitting.

But the chief limiting factor is that nukes are so prohibitively expensive that a massive increase in public subsidies would be needed. In Minnesota, there's a nuclear moratorium in effect. And, besides, the region's largest provider, Xcel, is committed to renewables like wind and solar, and to energy efficiency improvements like insulating buildings.

And so, it seems, building bunches of nuclear power plants to reduce carbon emissions is financially and practically pointless, at least in the United States.

Our nuclear power discussion didn't last long, because Abrahamson had much larger worries on his mind.

He leaned forward and said, slowly: "Do you realize that to meet the Paris Agreement on climate change, greenhouse emissions must be totally eliminated by 2100?"

The kicker: 80% of all emissions must end by 2050. Whoa.

Four years ago, 195 nations gathered in Paris and agreed that to avoid "climate calamity" world temps must be kept below preindustrial levels plus 2 degrees Celsius, preferably 1.5. While the agreement was remarkable, back home the diplomats found the will to actually get to solutions didn't align with the problem's urgency.

The next kicker: World temps have already risen by 1.1-degrees Celsius in the target time frame, and warming is accelerating. Which means the "calamity" level is less than a degree away.

Consider that relative to the sheer enormity of that challenge, the world is still at the talkity-talk stage. Scientists have warned about warming since the 1960s, and more recently a broad consensus of the world's top climate experts says we're at the hair-on-fire stage.

Among many other chilling warnings in the United Nations climate report released last week, Michael Oppenheimer, Princeton University geosciences professor and lead author, said that even if greenhouse emissions are aggressively reduced, oceans will rise 1 foot by 2100. If not, a likely 3-foot rise along with increasingly intense storms would become "unmanageable."

Sure, policymakers are talking as if warming is the crisis it is. But talk is easy. Just last week millions of young people worldwide skipped school to demand we get on with healing the planet that we've messed up and they'll inherit.

Inspiration for the global protest is 16-year-old Greta Thunberg of Sweden, who will be a young adult when climate chaos could be in full gloom if the present generation does little more than puff.

Carbon spews from cars, trucks and airplanes, from the black dirt of plowed fields, from cement-making, from power plants, and from oil and gas production. A huge problem is the mining of Alberta's expansive fields of tar sands (relevant to the Keystone Pipeline and Minnesota's Line 3 controversies since those leak-prone lines would carry "dirty" Canadian crude to large U.S. and world markets, causing still more Alberta earth to be ripped up and gobs more carbon released).

Trees and deep-rooted vegetation soak up carbon. Yet widespread land-clearing and deforestation proceeds largely unabated. Massive, frequent wildfires take out tinder forests, and there's massive destruction of rainforests in Brazil and Indonesia to clear land to raise beef cattle.

Deforestation releases carbon, while living trees soak up carbon and release life-sustaining oxygen. It's said that the Amazon Rainforest alone produces 20% of the world's oxygen.

Another particularly nasty greenhouse gas is methane from oil production, as well as from livestock waste and decaying organics in landfills and sewage treatment plants.

Vast stores of carbon and methane in permafrost are being released as warming thaws the tundra. Anchorage, Alaska, set a record temp of 90-degrees in July, a month that saw yet another world heat record.

It amounts to a staggering amount of heat-trapping stuff still going up as the experts rightly scream that 80% of emissions must end in just 30 years.

Possible? Sure, technically. But it doesn't help that the U.S., consumer of a quarter the world's energy with only 5% of its population, remains stuck in a ding-dong debate about whether climate change is real. The fossil-fuel industry led by Koch Industries pumps billions into political campaigns and financially supports various groups that too effectively perpetuate the anti-warming myth.

Then, too, President Donald Trump withdrew the U.S. from the Paris Agreement and instead is pushing more fossil fuel production, is relaxing auto emission-controls, and has gutted more than 80 environmental regulations — most recently one limiting methane release.

Just seven small countries are on track to cut emissions to meet the Paris target. India and China have done little, the U.S. and Russia less.

Even if the U.S. sheds its pathetic paranoia over climate change and joins a headlong push to reduce greenhouse emissions, warming's harsh effects will continue for decades because so much damaging gas is already in earth's paper-thin atmosphere.

As climate scientists have long predicted, we're seeing larger and more severe storms and hurricanes and their flooding, wildly irregular weather patterns, polar ice melt, species extinction, and drought (as in the already-dry U.S. Southwest).

Minnesota's cold winters have become so mild that robins stick around, unwanted bug pests are ranging farther north, and longer periods of ice-free lakes means more heat to decay algae and suck out life-supporting oxygen.

Oceans are continually rising from melting ice and thermal expansion (water expands as it warms). Mortgage lenders see dropping ocean-side property values with a big target on Florida — where Bloomberg reports a "climate exodus" from the Keys has begun. Insurance is being voided on property near dry forests where wildfire is a lightning strike away.

It's all happening now, with increasing intensity. Yet, greenhouse gas keeps saturating the atmosphere and trapping heat that otherwise would escape harmlessly into space.

Cynicism is a dreadful thing; it strangles hope and makes one a grumbling cuss. But with abundant basis, glum cynics say the world's a mess and getting messier with wars and poverty and social discord — and a warming climate that's a grave existential threat.

Still, hope persists: There's soaring public demand to address climate change, more reliability on renewables to generate electricity, growing use of bicycles for local travel, and radically improved batteries for motorcars and trucks.

Still, within the lifetimes of most, daunting climate effects will be greater by magnitudes as unwanted change outpaces the ability to adjust, prompting security planners to warn of resource wars and social upheaval, including mass migrations.

It may well be that present generations are, mostly, enjoying the pinnacle of human achievement and relative comfort.

What to do? Well, if you're young and think — with justification — that the world we're leaving to the kids won't be a very nice place, then consider a question in full ethical context: Why have kids and expose them to our mess? We older folks will probably just grumble away our remaining time, thinking that all creativity for positive cultural change went into Smartphones and gadgets we're not good at using.

But if you think — also with justification — that the world can fast-track actions to mitigate climate change, then pay heed to Greta, stop grumbling, get off the couch, and expend all the vigor you have to push real solutions.

You could also fly less, drive much less, and forgo red meat (more important than you'd think).

This climate change thing is mega-serious, folks. It won't solve itself.

Ron Way lives in Edina.