Saturday, February 10, 2018

Paper Drought or Real Drought?

I recently read an article entitled, "Time to Get Rid of Two Outdated Water Words: 'Drought' and 'Normal'" by Tom Philp. Once upon a time, Mr. Philp wrote about water policy for the Sacramento Bee (way back when I worked for the California Farm Water Coalition). He's since gone on to work for the Metropolitan Water District of Southern California (MWD); I've become a small-time shepherd and a farm advisor who works with ranchers. Our respective professional evolution, perhaps, explains a difference of option, at least about the meaning of the word "drought."

Mr. Philp writes, "In California, a drought only happens when a governor declares it to be so." From a public policy perspective, this may be true. An official drought declaration requires water agencies to take specific conservation actions. In the artificial environments we've created in our modern cities, I suppose the average person isn't impacted by drought until their water supplier requires them to use less water. Drought doesn't hit home until your waiter doesn't automatically bring you water at your favorite restaurant.

I appreciate the point that Mr. Philp goes on to make - that California has been drier than "normal" two years out of three since 2000. I'll come back to the word normal in a moment. Because we seem to have entered a prolonged "semi-drought," (Mr. Philp's term), he argues that we should always focus on water conservation. I concur; the conservation habits that we adopted individually and collectively during the 2012-2015 should be permanent behaviors.

The word "normal," as it is applied to weather and climate, is interesting to me. Normal, in this sense, has several meanings. From a statistical perspective, normal is synonymous with average. Many of us, myself included, also use normal to describe our future climatological expectations based on past experience. As I think about normal in terms of averages, I see Mr. Philp's point. In the 15 years I've kept precipitation records in Auburn, our average annual rainfall has been about 32 inches. If I take the average between the driest year and the wettest year in that period, our average is over 40 inches. Only once in the last 15 years has our actual rainfall equaled the average.

In terms of my own weather expectations, "normal" has become a less useful term as well. In 11 out of the last 15 years, our total precipitation has been below the mean - less than 32 inches. From month-to-month and from year-to-year, we seem to be experiencing more extremes (both of dry periods and rainfall). For example, in December 2015 we measured just 0.01 inches of rain in Auburn; in December 2017, we had 14.53 inches. I'm not sure what normal is anymore!

But while I can happily give up using the word normal to describe our weather and our hydrological conditions, I can't give up the word drought. As a rangeland livestock producer, drought has a direct impact on me regardless of any governor's official action. As I wrote in a paper I co-authored with a number of colleagues, "In fact, rangeland livestock ranchers were among the first affected by the abnormally warm, dry winters at the beginning of the current multiyear drought." To read the entire paper, see Coping with Drought on California Rangelands. As a sheep rancher, I rely on fall rain to germinate the grass that my sheep will graze in the winter. I rely on winter rain to keep the grass growing as my ewes begin to lamb. And I rely on spring rain to grow the grass that we'll come back to in the fall. I also rely on the fact that rain in the Sierra foothills means snow in the high country; our summer irrigation supplies depend on winter snow (see Grass, Water and Warmth for more details).

Because of the lack of "normal" weather over the last 15 years, drought figures into our annual and long term plans. We have far fewer sheep than our grazing land could support in the best years to be sure we're ready for the worst years. We maintain a list of sheep we would sell if the grass didn't grow. We've invested in equipment that allows us to haul drinking water to our sheep, and we've upgraded our irrigation system to make sure we're using water as efficiently as possible. In the wettest year on record (last year, we measured over 62 inches of rain in Auburn), drought entered into our annual planning process - even though Governor Brown declared the "drought" to be over.

As we move into an era of increasing climate uncertainty, I agree with Mr. Philp that water conservation should be the rule rather than the exception. We shouldn't wait for an official drought declaration to begin saving water (whether we're in an urban area or on a ranch). For me, however, drought is not an abstract concept. Regardless of a politician's signature on a drought declaration, drought for me is when the rain and snow don't come. As a rancher, it will remain a part of my normal vocabulary.

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