By Justin Mankin / Special To The Washington Post
The drought in the American West is not a passing crisis. It is the shape of things to come.
The past 20 months of rain, snow, heat and wildfire have been exceptional in our records of weather and climate. And they have conspired to make the most severe and widespread drought the region has experienced in the modern era, punctuating a 20-year period as dry as any time in at least the past 1,200 years.
The consequences have been swift, severe and extensive. Drought favors wildfire, and this year is just the latest in a series of catastrophic wildfire seasons: Flames have engulfed an area larger than the size of New Jersey. In June, Lake Mead, the largest reservoir in the country, which supplies water for the Hoover Powerplant, reached its lowest level since first filling in the 1930s. The Colorado River has declared its first water allocation shortage since its governing compact was signed in the early 1920s, entering uncharted political, legal and geophysical territory. While we do not yet know the full scope of loss, the economic consequences of the drought for 2020 is in the tens of billions of dollars.
Recently, the National Oceanic and Atmospheric Administration (NOAA) asked the scientists leading its Drought Task Force to consider the context, causes and future of this unyielding drought. With the lowest rain and snow and the third-highest temperatures on record since at least 1895, this drought covers an astounding 94 percent of the Western United States.
Our work suggests, though, that this drought is only extraordinary when we consider the climate we used to have, not the one we’ve committed ourselves to. The danger is that state and federal governments, businesses, advocates and other groups will continue to manage this drought as a disaster — a short-term event that requires emergency responses — rather than what it is: a transition to permanent water loss.
Why have conditions become so dire? An unlucky string of seasons of low rain and snow across Western states was the initial culprit. But the drought has been made much worse by searing temperatures in the West, part of a regional warming trend from global warming. Warm air evaporates rain and snow more quickly and dries soils and rivers and forests, priming the landscape for wildfires. While our greenhouse-gas emissions may not have caused the low precipitation that started this drought, human want has made it worse: The atmosphere is much warmer and thirstier than it would otherwise have been.
This means that crisis management will not suffice. Siphoning groundwater via regulatory loopholes in Arizona, building more dams like the one proposed just east of the Grand Canyon, or briefly injecting money to subsidize farmers, ranchers and water districts, will merely maintain an illusory socioeconomic and political status quo.
That may be appealing or even necessary, but it does not solve the problem. Western states face the risk of soils as dry as the past year, every four years in the coming decades. Because of this, solutions borne of crisis management won’t work for long. They consider the drought an anomaly from which we need to recover, rather than an emerging feature we need to abide. With recurrent droughts, relying on groundwater to compensate surface losses becomes unsustainable. Another reservoir in the already-dry and over-diverted Colorado River basin becomes an environmental stressor and a waste of resources. Emergency coffers meant to get working lands through hard times quickly become empty.
The only way to respond at the scale required is to reorient resources, institutions, regulations, supply chains and household practices to this drier reality. That is what it means to adapt. This requires updating our nation’s drought classification system that informs the allocation of emergency funds. It means overhauling century-old water and land management practices to accommodate more violent swings in dry and wet periods, as a water consortium in Northern California and some Colorado ranchers are working to do.
It means restructuring our power supply away from drought-vulnerable hydropower and shifting to other renewables. It means changing what we grow and where we grow it. It means hardening structures and changing building codes, while accommodating a more wildfire-prone landscape. It means upending water rights that were asserted in a wetter climate. This is the stuff of sound, long-term planning, not crisis management.
We tend to think of one-off disasters as having a beginning, a middle, and an end. So political leaders are understandably concerned with state and federal disaster declarations and emergency funds for farmers, ranchers, wildfire victims and water districts as the drought impacts life, wealth and livelihood, depressing state economies to the tune of billions of dollars. But the bigger question is what happens if this drought doesn’t go away. An emergency can only be an emergency for so long. Eventually it becomes something else. What we are witnessing in the West is an acute crisis unfolding into a near-permanent one.
Present drought conditions will only “end” when reservoirs and rivers refill, which will take a number of very wet (and cold) years across the whole of the West. That may not be in the cards. The Southwest monsoon rains this summer illustrate this point: Despite Arizona welcoming an extremely wet season, 86 percent of the state still remains in drought. Barring a reversal of global warming, the evaporative demands of a warmer atmosphere will draw more water from the land and melt the mountain snowpacks that keep Western rivers running. The region will slip into drought more easily in the coming years, even in the face of once “normal” rain and snow. And each time it will be harder to emerge.
Drought, by definition, is an aberration, but to treat this one as such only deepens our vulnerability. Accepting aridity, and rejecting shortsighted and maladaptive responses, is central to managing drought risks for the more than 60 million people reliant on the West’s dwindling water; and for the generations to come. An era of drought in the Western United States has begun. Our focus should be on adapting to this dry run, rather than hoping for it to end.
Justin Mankin is a climate scientist and assistant professor of geography at Dartmouth College. He serves as a co-lead of the NOAA Drought Task Force.