On Thanksgiving day, among the many things I felt grateful for was a selfish one: the temperature outside nearly hit sixty degrees.
I love a warm day, the product of a childhood spent in the desert environs of Phoenix, where warm winter days were the norm. I have fond memories of hikes and horseback rides on sunny December holidays, meandering among cacti and creosote bushes. I’d also head out the back door of our house, determined to play outside under the desert sun. Warm days became part of my world view. In my twenties, I focused on something I called the ‘Perfect Temperature’ – the sweet spot during a day when life felt ripe and anything seemed possible. Roughly 72 degrees, the sweet spot was a combination of measurement and anticipation. During the summer, it often happened before dawn, and if I was driving to work I rolled down the window letting the sweetness fill the car. During the winter, the days often climbed to the Perfect Temperature and stayed there, it seemed. Happily, I basked in Phoenix’s balmy winters.
I just never expected to do so in Santa Fe. At 7000 feet, a sixty degree day this late in the season is not particularly normal. Neither is the long stretch of dry weather we’ve enjoyed all fall, a stretch that weather forecasters say may extend all the way to summer. This isn’t good news, of course, but it’s hard to complain about it. We will eventually, of course, if it keeps up as predicted.
So far in 2012, we’ve received less than half of our annual precipitation – which is a paltry 12 inches to begin with – and the land looks it. When I go for a walk with our dog through a patch of pinon country near our home, I try not to look at the desiccated grass plants along the trail. We did get a decent amount of rain in August, which caused a bright green flush of life in September. Weeds shot out of the ground like Roman rockets, and wildflowers bloomed almost as far as the eye could see. And thanks to the warm weather, the show went on and on. But now the plants seem confused. “Where’s the snow?” they seem to ask. “Should we think about budding?” ask the trees. “Don’t!” I say in response. “Don’t be fooled!”
It’ll snow some day this winter, as I remind my hopeful son, who loves the season. The trees know this too, of course, and won’t bud until spring – but then what? If the dry weather persists, what will they do for water? I saw a report recently that said in prolonged periods of hot and dry conditions, trees die quickly. Many species can’t handle heat stress very well, partly due to shallow root systems, and mortality can happen fast across wide landscapes if precipitation remains scant. And obviously, tress can’t simply pick up move to a new home. In Texas, an estimated 300 million trees have died since dry times set up in 2011. That’s approximately 10% of the total amount of trees in the state, according to researchers. That’s a lot of good carbon going to waste.
I like a warm day, but a ponderosa pine may feel differently.
Here’s a picture of trees in Texas:
You may notice that I haven’t used the “d” word yet – drought. That’s because it’s important to choose our words carefully. Words have power. No one says that the Sahara suffers from “drought” conditions, for example. It’s a desert, and deserts don’t have droughts. Normal in a desert is a tiny amount of precipitation, usually something like 3-4 inches or so. ‘Not normal’ in a desert means more precipitation – whatever the opposite of a drought is – which generally is good news for plants, animals, and humans.
When we use the word “drought” to describe Texas or New Mexico, however, we imply that current conditions are not normal and that they’ll return to average once again, be it in a year or two or three (which is still bad news for trees). Consider the catastrophic Dust Bowl – the subject of a documentary on PBS this week – which devastated the southern Great Plains with the nation’s worst drought ever. Sure, the great Plow Up of the Plains by reckless humans in the 1920s set the stage for the tragedy, but it was the cessation of precipitation that set the tragedy in motion. Eventually, the rains returned, doing far more to heal the land and its people than any government program. And the rains stuck around, more or less, up to the current period. The Dust Bowl was a drought. What’s happening today is something else.
Long-term climate models for the Southwest indicate increased temperatures and decreasing moisture. Of this, there is now little doubt among scientists. So, when do we begin to revaluate the word “drought” in our everyday language?
A recent letter to John Fleck, the Science editor of the Albuquerque Journal, illuminates this issue well. The letter-writer asked: “When does a drought become the new norm; that is, it’s no longer a ‘deficiency’ and so no longer a drought?”
“It’s a good question,” Fleck responded, “with no easy answer, because it gets to the heart of what we mean by “drought”…a slippery, ill-defined term that sometimes conceals as much as it reveals. If long-term aridity becomes the norm in New Mexico as a result of a changing climate, will we stop calling it “drought” and just cope?”
Fleck notes that the current “drought” is comparable to the big drought of the 1950s, which was eventually followed by a period of abundant rain and snow, lasting all the way through the 1980s. Although many New Mexicans can’t recall the dry times of the 1950s, the implication is that sooner or later droughts break and wet times return – as they have done repeatedly in the past.
But this time things are different.
“Rainy spells and dry spells come and go,” writes Fleck. “But that natural variability is now superimposed on a long-term warming trend, the result of a planet warmed by rising greenhouse gases. So while New Mexico has been slightly wetter the past two years, compared with 1955-56, according to the National Climatic Data Center, it also has been substantially warmer — 1.7 degrees Fahrenheit on average.”
And according to University of Arizona researcher Dave Breshears, who tracks drought’s effect on forests, “it’s going to keep getting warmer.”
So, are we in a drought or not?
It depends, says Fleck. Scientists have different ways to measure and categorize dry periods of time, including the widely-used Palmer Drought Severity Index, which looks at both temperature and precipitation. According to the Index, New Mexico is in a serious drought situation. So, according to this metric, the answer would be ‘Yes, we are in a bad drought.’ But other metrics draw different conclusions, Fleck says. For example, the global increase in temperature underway means that the ‘bar’ for drought is being raised. If ‘normal’ is changing, then definitions of ‘not normal’ need to change as well, including a definition of drought.
One new line of analysis by researchers, says Fleck, focuses on impacts instead of levels of precipitation. What’s happening to the Colorado River, for instance, on which so many people and industries depend? Well, the impact has been severe. How about the impact of the dry weather on ranchers, farmers, and dairies? Ditto.
Clearly, we’re in some sort of transition, reflected by the shifting definitions of drought and the consequences of a drying climate. Unfortunately, this transition isn’t getting much air time in front of the public. So far, the media is sticking to the standard definitions, which sends the message that the ‘old’ normal is still in operation. Hang on, they tell readers and viewers, things will get better. They always have!
This is unfortunate because if there’s a ‘new’ normal emerging, as it appears to be doing, then we should get busy making plans to adjust and adapt. Still, I love a warm day and while we sort out definitions and plans for the future, I’m going to enjoy our dog walks through pinon country, pondering the dryness of it all.
Here’s a photo near our home from a few years ago. Normal or not?: