Hugh Pickens writes "Megan Garber writes that last weekend, a US Airways flight taxiing for takeoff from Washington's Reagan National Airport got stuck on the tarmac for three hours because the tarmac had softened from the heat, and the plane had created — and then sunk into — a groove from which it couldn't, at first, be removed. So what makes an asphalt tarmac, the foundation of our mighty air network, turn to sponge? The answer is that our most common airport surface might not be fully suited to its new, excessively heated environment. One of asphalt's main selling points is precisely the fact that, because of its pitchy components, it's not quite solid: It's 'viscoelastic,' which makes it an ideal surface for the airport environment. As a solid, asphalt is sturdy; as a substance that can be made from — and transitioned back to — liquid, it's relatively easy to work with. And, crucially, it makes for runway repair work that is relatively efficient. But those selling points can also be asphalt's Achilles heel. Viscoelasticity means that the asphalt is always capable of liquefying. The problem, for National Airport's tarmac and the passengers who were stuck on it, was that this weekend's 100+-degree temperatures were a little less room temperature-like than they'd normally be, making the asphalt a little less solid that it would normally be. 'As ironic and as funny as the imgur seen round the world is, it may also be a hint at what's in store for us in a future of weirding weather. An aircraft sinking augurs the new challenges we'll face as temperatures keep rising.'"