If greenhouse gases continue to rise, all models predict that the planet is headed to a future with an Arctic that is ice-free in the summer. The predictions of when this will occur vary by model, from as soon as a decade or two from now to closer to the end of the century.
We live in the natural world and in some respects are at the mercy of the weather and therefore the climate. And so the climate-human system can have some pretty serious "self-corrections" built into it.
Of all the geoengineering ideas, the one often cited as the simplest, most obvious one, the one we should get started on right away is painting roofs white -- after all how can that not help? How indeed.
We have serious confirmation of how bad our situation can get. And, it was well reported by a part of the Washington Post. A part, we can suspect, that George F. Will and the opinion page editors don't bother to read.