We woke up yesterday to fresh snow in the mountains, and it reminded me of the snow survey I did the end of March that I never posted.
Snow surveys are conducted throughout the western U.S. to help predict stream flows. The Natural Resource Conservation Service, an agency of the U.S. Department of Agriculture, runs the program. In Great Basin National Park, three snow courses are found along Baker Creek. They were established in 1942 (when the land was managed by the U.S. Forest Service), and almost every year a snow survey is conducted at the end of February and the end of March.
Mark and I started near the Baker Creek campground on a snowy morning on April 1, the last day we could do it to be in time for the April 1 forecast.
By the time we walked/skiied up to the trailhead at 8,000 feet, the precipitation had stopped. But there was barely enough snow to ski on, and soon we were walking again.
Fortunately after the first site at 8250 ft, we found some nice snow. The sun came out, making a beautiful day. When I first started doing the snow survey about three years ago, it seemed so long. Now it just seems like a pleasant outing. (I still am sore at the end of the day, though!)
A smile from Mark, despite the skis picking up too much snow. It was right around freezing, and the snow was sticky.
The second site is usually cold because it's shady and down near the creek. This year it didn't seem too bad. At each snow course we took five measurements.
Here's Mark getting the tube ready to push into the snow. How far down will it go?
We measured the snow depth, how much snow was in the tube, and then weighed the tube to get the snow water equivalent, or how much water is in the snow. That's the most important measurement for forecasting.
I couldn't help but snap a few photos on the way up to the third site. The snow was deep enough to make some interesting patterns right near the creek.
It's a really cool feeling making fresh tracks in fresh snow. It had snowed the night before, and the trees still had lots of snow on them.
This slope had a huge avalanche in 2005 that went all the way down the side of the mountain, across the creek, and part way up the other side. I'm always fascinated to see who the vegetation is growing.
Finally we made it to the third site. This is the prettiest site, a large meadow. I could hang out here for a couple hours.
This site has an extra orange marker, which is an aerial marker. In the old days, a plane would fly by and an observer would get an estimate of snow depth by how much snow covered the marker. Today the NRCS has installed a network of Snotel sites that give them much more accurate information than the fly-by method.
Once we completed all the measurements, we headed back down the trail. The snow was melting faster, and we had some extra rocks to traverse. It was not the easy downhill we were hoping for.
And then the snow ran out. We had to take off our skis and hike. Boo.
We were really hoping that someone would have opened the gate and driven our vehicle for us up to the trailhead, but no such luck. We still had more hiking to do.
The silver lining is that we got to see a couple marmots! They were actually seen in late February this year.
It's cool to have such a long dataset to see how the snow depths and snow water equivalents have fluctuated over the years. Over the whole period, there is a slight downward trend, even though the overall precipitation record shows a slight increase. This indicates that we are getting more snow as rain than snow, which changes the timing for peak stream flow and how much water is stored as snow into later into the summer. Looks like times are a'changing!
Here's what the snow survey looked like in 2013 and 2012.
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