Say we're all sitting on a roof. This smooth roof has a slight slant. We're slowly sliding to the distant end. Where the edge is and what's below we don't know.

Think of the roof as climate. We're going somewhere, downhill for sure, to an unknown end.

We've bought our world weather with energy from the earth, carbon dioxide as currency. We'll never get our money back. What we have we own. As they say in the antique business, you break it, you own it.

We were warned of this, but few of us recognized the trend of the last 200 years, so here we are.

An article in a recent The New York Times magazine states this well.

"The Deluge" is the header for the story. Sub-head: How do we live with the fact that the world we knew is going, and, in some cases is already gone?"

Author Jon Mooallem uses a phrase that has been applied to birds: "shifting baseline syndrome."

If you begin birding today, your first serious walk with binoculars, you could come home and say, "Wow, did I ever see a lot of birds."

I could reply, "I remember when …" (and kill the conversation). But truly you would have seen more birds 20 or 30 or 40 years ago. Your response to your bird walk then would be even more enthusiastic. The baseline by which we measure our bird pleasure has shifted.

The future we've been warned about has become the present. It's true for birds. Mooallem believes it's true for climate, too.

Regardless of today's weather, reality is our steady slide down the allegorical roof. We're most likely headed for a scary climate future. It's hard, though, to notice a worsening situation if you don't see the occasional nicks and dings in the roof as we slide by.

You could tell me that there always have been nicks and dings. So, hey, just ignore them.

Wilmington, N.C., is experiencing 90 days per year of flooded streets and neighborhoods caused by high tides and storm surges. The city calls it nuisance flooding. If you parse "nuisance" does it eventually become "really big problem?"

Rescue? Maybe a genuine futuristic scheme, or ropes and ladders, or FEMA. Wishful thinking.

The word "solastalgia," says Australian philosopher Glenn Albrecht, means a form of homesickness one gets when one is still at home. In an over-heated world, we'd still be at home. It just would seem like someplace else.

We can never return to where we began — you break it, you own it — but we know how to avoid disaster. We could slow the slide, perhaps forever.

Think now of how we're doing with birds. We're doing much worse with climate.

Save ourselves from ourselves? We understand how to do it.