Arizona’s not on fire.
But that doesn’t mean we’re not having our own little disaster.
On the heels of “exceptional” drought and the hottest, driest Arizona summer on record, the U.S. Department of Agriculture has declared farmers and ranchers in 13 Arizona counties are eligible for up to $500,000 in emergency disaster loans due to the drought.
That includes Gila, Apache and Navajo counties — with conditions most severe in Gila County.
And it could easily get worse.
We’re probably in for a warm, dry winter, according to The National Oceanic and Atmospheric Administration. The surface waters of the tropical Pacific have warmed up, creating La Nina conditions that normally produces a dry, warm winter in the Southwest. The forecast’s more gloomy than an earlier Farmer’s Almanac forecast of a near-normal winter.
Arizona hasn’t seen such a scorching, bone-dry summer since record keeping began in 1895, according to the National Weather Service.
“Earlier, we gave you the bad news about the hottest all-time summer (June-Jul-Aug) in Arizona,” tweeted the National Weather Service. “Well, even worse news: it was also the driest summer on record in Arizona. Much of southern Arizona receives close to 50% of their annual average during the summer – not good.”
Inciweb is still tracking 17 wildfires in Arizona, long after the monsoon normally douses active fires. None are currently threatening structures or spreading rapidly. That’s nothing compared to the worse fire season on record only about half way finished in California, Oregon and Washington. Those fires have raced through more than four million acres and inflicted hundreds of billions in damage. The fires have killed at least 36 people, with dozens still missing.
In California alone, 17,000 firefighters continue to battle 25 major fires that have burned more than 3.3 million acres — an all-time California record. The 10 largest wildfires in California history have all occurred since 2000. Experts blame a record-breaking drought, a shift of population into fire-prone areas, years of fire suppression that enabled fuels to build up and the impact of ongoing climate change.
The National Interagency Fire Center reports that while the total number of fires has actually declined in the past 30 years in the American West, the total number of acres burned has exploded – as a result of more mega-fires.
Arizona’s facing a similar danger, along with most western U.S. states. The consulting firm Four Twenty Seven has compiled a climate change risk assessment for every county in the United States. The analysis includes projections for drought, wildfires, extreme heat, extreme rainfall, hurricanes or sea level rise.
Navajo, Apache and Gila Counties all faced greatly increased wildfire risk, while all of low-elevation southern Arizona faces greatly increased water and heat stress risk.
The heat shattered records in the Valley this year, which had at least 53 days above 100 degrees. On 14 of those days, the temperature topped 114. The Valley had 28 days where the temperature never dipped below 90. That helped drive people to the high country despite the pandemic, resulting in a relatively good summer for high country tourism — despite the forest closures due to the threat of wildfires.
Unfortunately, forecasters fear the La Nina sea surface warming will compound the effects of the hot, dry summer — likely minimizing the snow pack the Valley relies on to refill the reservoirs on the Salt and Verde River that supply the Valley. This could also mean a tough winter for the state’s two ski resorts, bad news for the hard-pressed White Mountain Apache Tribe.
La Nina sea surface warming recurs every 3-4 years on the average — and tilts the odds towards a dry winter. The opposite condition — El Nino — cools Pacific surface waters and increases the odds of a wet Arizona winter. Both conditions have their effect by affecting the path of the jet stream — which steers winter storms either into Arizona or shifts them further north.
Forecasters at the Climate Prediction Center said there’s a 75% chance La Nina will persist through the winter, but may not extend into the spring. The shift in the jet stream will likely dry out Southern California, Arizona and New Mexico — but could mean a wetter-than-normal winter for the Pacific Northwest, Alaska, Canada and the Northern Great Plains. The shift into La Nina conditions has also already kicked the North Atlantic hurricane season into high gear.
Fortunately, Salt River Project’s network of reservoirs continues to cushion the tremendous variability in rain from one season to the next. The Verde system reservoirs have dwindled to 56% of capacity, but the much more important Salt River reservoirs remain at 86% of capacity — with 1.7 million acre-feet in storage.
Earlier studies have demonstrated that the Salt and Verde river systems are much more resilient to the effects of climate change that most other systems — including the crucial reservoirs on the Colorado River. The Arizona State University study demonstrated that runoff from the Salt and Verde comes earlier in the season than other, more vulnerable watersheds when it comes to the impact of global warming.
Arizona has already agreed to cut its water allotment from the Colorado River by about 200,000 acre feet — or about 7%. Current projections suggest further cuts in 2022, especially if this turns into a dry winter.
Currently, the near failure of the monsoon has left Gila County and the White Mountains in “extreme drought” according to the National Weather Service’s Drought monitor. Northern Apache and Navajo counties are mostly in severe to moderate drought.
The “extreme drought” conditions now cover about two-thirds of Arizona, half of Nevada and Colorado, almost all of Utah and maybe a third of New Mexico. The entire southwest remains in moderate to extreme drought, with the exception of coastal California.