There's a big dune on the East side of the Columbia that I ski past whenever I ski the loop trail and every time I go by it I look at it to see if I can notice any changes in it. Dunes amaze me; they seem to defy entropy. We would run barefoot sprint intervals up the side of the dune on the WHS cross country running team and every step would push down buckets of sand. But the dune just rebuilds itself, smooths over the footsteps and continues to get taller. Last week someone even dug a cave into the side of the dune and when I skied by yesterday I couldn't even see a suggestion of a cave. Now some sparse grasses are starting to poke through the sand on the South side of the dune. Is the vegetation going to spread and overtake the dune? How long does that take? Could one write an equation to predict that if one knew rainfall, temp, wind speed & direction, surrounding vegetation, etc? How cool would it be to plot the growth and movement of the dune over time and would you be able to see the effects of the seasons on such a graph? My eye and my memory are not accurate enough to tell whether the crest of the dune is moving, either vertically or laterally, but I think it is.