Climate change, yukigata, and another dry year in the Southwest
|Jonathan P. Thompson |
April 2, 2021
For four decades, my grandparents ran a farm in the Animas Valley north of Durango, Colorado. They knew when it was time to put out the tomatoes they had started indoors not by looking at the calendar, but by keeping an eye each spring on a particular northerly facing slope on Missionary Ridge. When the snow was all melted from the slope, the threat of a killing freeze had passed, meaning the tomatoes would be safe outdoors.
Their snow-pattern planting calendar—known in Japan as yukigata—isn’t unique. No matter where you go, so long as there’s a hill or mountain in sight, farmers follow a similar ritual. Over in the Montezuma Valley gardeners wait until Ute Mountain is free of snow to plant. Folks along Utah’s Wasatch Front keep an eye on the Sleigh Runner crevasse on Box Elder Peak. In the Grand Valley of Colorado, it would be foolish to plant before the Swan’s Neck has melted. And in the North Fork Valley of Western Colorado, gardeners wait for the Devil’s Neck on Mt. Lamborn to “break.”
And, pretty much no matter where you go, diminishing precipitation and a warming climate are disappearing the yukigata ever earlier in the year, throwing the planting schedule out of whack. My grandparents’ Missionary Ridge snow-spot reliably held snow until late May or early June. Over the last couple of decades, however, it has been known to vanish as early as March. In early June of 2002, my grandparents’ yukigata, by then long gone for the season, was charred in the 73,000-acre Missionary Ridge Fire.
That was near the beginning of what has turned out to be a virtually unrelenting, 20-year-long dry spell that is rendering the word “drought” somewhat meaningless. It makes more sense to call it aridification or, as some prefer, the “new normal.”
But the trouble with normal, as singer-songwriter Bruce Cockburn noted, is it always gets worse: for the farmers who rely on the snowmelt to fill the reservoirs that keep their ditches flowing through the summer; for the millions of people who draw water from the Colorado River system; for the rafters who flock to the region’s rivers each spring and summer; for all those affected by wildfires and their smoke; and for the wildlife that relies on a decent amount of moisture in the soil and streams. Snow Studies @snowstudiesAnother dust event in Colorado mountains last night. This picture was taken just before evening near Moab by Jeff Deems. The USGS dust cams towards the 4 corners were not as bad. It may be that central/northern mountains were hit harder, we’ll see the next CODOS tour. March 30th 20215 Retweets14 Likes
As the 2021 water year reached its April 1 midpoint, most of the yukigata in the Four Corners Country were still in place. The peak of Ute Mountain still wears a blanket of white and a smidgeon of snow still caps the north face of Smelter Mountain, Durango’s planting calendar. That’s reassuring, an indication that we’re a lot better off than the ultra-dry years of 2002, 2013, or 2018, when there was virtually no snow on Smelter Mountain in December, let alone April.
Yet the figurative yukigata pattern revealed in the climatic data paints a different picture, one in which year after year of dryness have piled up to grim effect. Not only that, but despite a series of strong storms in late winter, the snowpack in most of the San Juan Mountains is below normal, with virtually no chance now of catching up. Add up the series of dry years, the below-normal snowpack, and warmer temperatures, and you end up with extreme drought conditions covering a good portion of the Southwest, which will inevitably lead to meagre streamflows, wildfires, and water restrictions this summer.
The good news is that if you’re one of the hordes of folks who didn’t win the river-running-permit lottery, you may not be missing out on much. The San Juan River in Utah is running at just above 500 cubic feet per second, which is almost a guarantee of some serious bottom-dragging in the silt of Lake Powell’s backwash. The Salt River in Arizona, which is usually crammed with boaters this time of year, is a virtual trickle, not even navigable by kayak. McPhee Reservoir is so low that you might as well forget about risking your life on Snaggletooth. The only bright spot is the headwaters of the Rio Grande, where the snowpack levels were right at normal as of April 1, but with warmer-than-normal temperatures forecast for the rest of the spring that may not hold.