Fighting snow blindness in high summer

I'm looking around me, and every visual cue suggests I'm at a ski resort in the middle of winter. There are hills covered top to bottom in pure white powder. Kids sliding happily down them. Big parking pullouts with cars side by side. Plowed roads.

But this isn't Tahoe in January. This is the New Mexico desert in late July, and it's baking hot outside.

I'm actually at White Sands National Monument, 275 square miles of the world's largest gypsum dune field. I'm visiting here as part of Road Trip 2007, my tour of science and technology sites around the American Southwest. And even as I attempt to fight off snow blindness from the incredibly bright light glaring off these nearly pure-white dunes, I'm simply amazed by what I'm seeing.

The dunes are the result of endless amounts of gypsum sand blowing from the southwest to the northeast, about 15 miles from New Mexico's Lake Lucero. The gypsum had first come down from the nearby mountains, and then evaporated, leaving crystals to be blown toward the dunes.

What happens next is curious: the sand blows onto the dunes, and over the course of the year, blows up, over and then off the side, meaning that the dunes are known to "move" as much as 30 feet a year as the sand essentially leapfrogs itself, courtesy of the wind.

I had heard that the monument was best visited at sunset, so on Thursday night I raced there from Tucson, Ariz., where I had done stories and photo galleries on the Titan Missile Museum and the airplane boneyards at both the Pima Air and Space Museum and the Aerospace Maintenance and Regeneration Group at Davis-Monthan Air Force base.

But while I made it to White Sands before sunset, it was far too cloudy to get the desired effect.

Still, a sky of storm clouds, the white dunes resplendent in their enormity, and what was left of the light made for a stunning experience. I was so impressed, I decided to return Friday, in full daylight.

That's when I encountered the summer version of near snow-blindness, something I wasn't expecting. But it was worth it as I climbed the dunes and watched groups of schoolchildren sledding down them, shrieking and giggling with glee.

Kids are not the only wildlife found here, though.

There's also a plethora of animals and vegetation. Among the beasts are kit foxes, cactus wren, bleached earless lizards and more. As for plant life, there are purple-colored sand verbena, 30-plus-feet high yuccas (generally with only a few of those feet sticking up above the dunes), Claret cup cactus and much more.

There are also four forms of the dunes: dome dunes, which are the first to form from the gypsum sand blowoff from Lake Lucero; barchan dunes, which are crescent-shaped and generated in areas with high winds, but not much sand; transverse dunes, which form long ridges of sand in areas with lots of sand; and parabolic dunes, which are anchored by plants and which invert their shape on the dune field edges.

A bit of a head trip
The White Sands National Monument is on the edge of the White Sands Missile Range, which is an odd thing, especially since I made my Friday visit to the dunes less than an hour after leaving the missile range. Going from one of the most technologically advanced facilities in the world to a place with no technology in such close proximity is a bit of a head trip.

Also a head trip was looking at some of the yucca plants sticking their heads up through the dunes. Despite the preponderance of life here, it feels pretty devoid of it. And these yuccas seem to be the exception to the rule, even though it's not really true.

But the yuccas--and many of the other life forms here--have made a remarkable adaptation to this deeply inhospitable environment. According to the official map, the yuccas that do survive manage to do so by sticking their stems above the sand, and anchoring themselves inside the dunes. That can end up creating what are known as "pedestal" dunes, which don't migrate, and that turn out to be nearly rock-solid and more exposed than the normal dunes.

Anyway, White Sands is quite the spectacle. You drive in from Highway 70 with no real idea what you're going to see. At first, you see hints of the white sand sticking up above normal green desert vegetation. You drive past the visitor center, and then follow a several-mile-long road out to the dunes.

Then, suddenly, there they are. For nearly as far as the eye can see, there are these white dunes, dominating the horizon and almost taking your breath away.

Now, if only I can overcome my desire to go skiing.