Alexandria Ocasio-Cortez, the Joan of Arc of the modern left, has made some predictions: 

Millennials, and Gen Z, and all these folks that come after us, are looking up and we're like 'the world will end in 12 years if we don't address climate change', and your biggest issue is how are we gonna pay for it?

...and...

Millions and millions will die.

So we all have twelve years to live.  To pay off our mortgage.  To see the kids off to college (don't worry; they won't graduate, and it won't be their fault; carbon poisoning will get them long before their final exams).  We may as well splurge and buy the last new car we'll ever need.

She isn't the first.  Before climate change reared its ugly head (or thundercloud) to exterminate us, there was the threat of population explosion:

The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now. At this late date nothing can prevent a substantial increase in the world death rate.

–Paul Erlich, The Population Bomb 

I guess we survived the '70s.

Then there were all those aerosol cans destroying the ozone layer — death by radiation and skin cancer.  Global cooling resulting in a new and terrible Ice Age.  Al Gore proclaimed every other year that we had only ten years left.  (Give him credit: he'll eventually be right if he lives long enough.)

The question that is never answered is, Who says?

According to some researchers, the Earth can support a population of 50 billion or more.  And fossil fuel, which was supposed to run out sometime soon (50 years, give or take), now, like June, seems to be bustin' out all over.

So who says the end is at hand?

Saying "the end is near" used to be the province of preachers on street corners.  They had a specific terminus in mind: the return of the messiah Jesus to reign in Jerusalem.

That's not quite what the global alarmists have in mind.  But it does bring out one point: none of the alarmists seems to consider what role a deity (or the Deity) may play in the upcoming demise of our planet.

If the globe is just a hunk of rock hurtling unguided through space, and humans are nothing but another jumbled life form that evolved from the primordial swamp, then our fate isn't very important.  We may live or become extinct without affecting any vast eternal purpose.  In fact, the sooner our extinction, the better, according to some proponents.

But if there is a Creator (a theory never addressed by the alarmists), then perhaps there are quite different plans for our future.

In the novel The Mudlark (1949), the author puts an address into the mouth of the British Prime Minister, Mr. Disraeli:

But Mr. Malthus ... proved that in time the human race would outstrip the capacity of all the lands of the earth.  I am not a born mathematician; I make no attack on this abstraction.  But to meet such a condition, if it ever arises, I place my faith in the ingenuity of Man,  which I doubt that even Mr. Mathus could have calculated to its ultimate  extent; and I place my faith, if the House pleases, in that which confounds all mathematics — the Divine Providence of the Loaves and Fishes.

The screenwriter of a wonderful sword-and-sandal epic of the fifties (Sign of the Pagan, 1954) has Pope Leo reply to Attila the Hun (played to perfection by Jack Palance), when the latter claims that it is written that Rome will fall to him, "Written by whom?  Who can write or who can know what is in the mind of God?"

To wit, that seems an appropriate response to all of our modern prophets of the end of humanity and the world: is it so written?  Really?  How do you know?  Who told you?  When, and by whom?