Tyler Spence sets his keister in the dune snow, with a harness around his torso as a taut line rises to a kite perched overhead in a steady wind. Itâs the same sort of kite (more like a sail) that drags surfers across the Lake Michigan chop, which is several yards behind our backs, now a quietly unstable mass of thick, crusted ice. When ready, Spence rocks up onto his snowboard. Itâs as if heâs taken his foot off of an imaginary brake pedal. The wind propels him toward the slopping dune. I chase after him on my cross-country skis, but Iâm no match. I watch him immediately shrink to the size of an ant, just like the sledders who are picking their slopes around him at Warren Dunes State Park in Sawyer.