The American West is currently suffering from a record-setting heat wave and deadly wildfires. Tragically, 19 fire fighters died Sunday in Prescott, Arizona fighting the Yarnell Hill Fire, one of the many fires that are currently burning through the west. As we've come to see following events such as this, people are asking if or how this is related to global warming. Below are some good explanations of how fires and heatwaves are or are not related to climate change.
Seth Borenstein at Wunderground explains that nighttime heat is the most dangerous part of the current heatwave in the Southwest:
"Nighttime heat is especially bad," said Eli Jacks, chief of fire and public weather services at the National Weather Service. "Not to get below 90 is crazy."
If you aren't in an air-conditioned place, "your body never has a chance to recover" at night, Jacks said. Normally the "feels-like" index - which factors in temperature and humidity - has to get to 80 degrees or below for your body to recover from the daytime heat, Jacks said.
The lack of nighttime cooling is more dangerous than the 117 degree all-time record in Las Vegas, experts said.
Andrew Freedman at Climate Central puts these wildfires into the context of climate change:
In Arizona, the current drought, combined with the regional heat wave, has created extremely dangerous wildfire conditions. Three quarters of the state of Arizona is experiencing “severe” to “exceptional” drought conditions, according to the latest U.S. Drought Monitor. In neighboring New Mexico, conditions are even more dire, with about 45 percent of the state experiencing “exceptional” drought, the worst-possible category.
Long-running precipitation deficits, including a below-average winter snowpack, have led to extremely dry soil moisture conditions in Arizona and New Mexico, in particular, and in other states across the West.
In recent years, the Southwest has trended toward drier and warmer conditions, which is consistent with climate-model projections that show that the region may become more arid in the coming decades, due in large part to manmade global warming. In fact, Arizona was the fastest warming state in the contiguous U.S. since the mid-1970s, with average surface temperatures increasing by 0.72°F per decade since 1970.
Felicity Barringer and Kenneth Chang at The New York Times report that scientists are calling this a "new normal" for the American west:
Warmer winters mean less snowfall. More of the winter precipitation falls as rain, which quickly flows away in streams instead of seeping deep underground.
The soils then dry out earlier and more quickly in May and June. “It’s the most arid time of year,” Dr. Garfin said. “It’s windy as well.”
The growing season also starts earlier, so there is more to burn.
“The fire season has lengthened substantially, by two months, over the last 30 years,” said Craig D. Allen, a research ecologist at the United States Geological Survey station at Bandelier National Monument in New Mexico.
Borenstein also answered whether this heat wave and wildfire was related to global warming:
No single event can be blamed solely on man-made global warming, scientists and meteorologists say. But this is the type of heat wave than scientists have long said will be more common as the world warms.
Some, but not all, scientists also theorize that the jet stream is having more of these crazy kinks lately because of a warming Arctic and melting sea ice.
Pennsylvania State University climate scientist Michael Mann said there's an element of randomness in the current weather. Yet with all-time heat records in the past few years being broken at three times the expected rate, he said, "there can be little doubt that climate change and global warming are playing a role."
It is worth-noting that as climate deniers or apologists or whatever you care to call them are always quick to say, we've always had wild fires and storms and heat waves and floods. That's why scientists and journalists and even politicians like President Obama are usually careful to say that no particular event was caused by climate change, but that global warming makes these events more likely to occur.
So if you don't like this heat wave and would prefer there to be fewer wild fires, you should want to stop global warming. For an excellent explanation on how the American West will suffer even more later this century, watch David Roberts' excellent talk "Climate Change is Simple." Here's the bottom line: if we burn all the fossil fuels that the oil companies are already planning to burn, we will eventually have parts of the US that will be uninhabitable (read: too hot to live).
In another post worth another look, last year, Roberts went deep into different ways we use language to discuss whether the Colorado wildfires were connected to climate change:
With this in mind, it’s clear that the question as it’s frequently asked — “did climate change cause the fires?” — is not going to get us the answer we want. If it’s yes or no, the answer is “yes.” But that doesn’t tell us much. What people really want to know when they ask that question is, “how proximate a cause is climate change?”
When we ask the question like that, we start to see why climate is such a wicked problem. Human beings, by virtue of their evolution, physiology, and socialization, are designed to heed causes within a particular range between proximate and distal. If I find my kid next to an overturned glass and a puddle of milk and ask him why the milk is spilled, I don’t care about the neurons firing and the muscles contracting. That’s too proximate. I don’t care about humans evolving with poor peripheral vision. That’s too distal. I care about my kid reaching for it and knocking it over. That’s not the only level of causal explanation that is correct, but it’s the level of causal explanation that is most meaningful to me.
For a given effect — a fire, a flood, a dead forest — climate change is almost always too distal a cause to make a visceral impression on us. We’re just not built to pay heed to those 1 percent margins. It’s too abstract. The problem is, wildfires being 1 percent more likely averaged over the whole globe actually means a lot more fires, a lot more damage, loss, and human suffering. Part of managing the Anthropocene is finding ways of making distal causes visceral, giving them a bigger role in our thinking and institutions.
That’s what the “did climate change cause XYZ?” questions are always really about: how proximate a cause climate change is, how immediate its effects are in our lives, how close it is.
If all of this feels a bit like deja vu, it's because we have this conversation every summer in recent years. And in the Fall when more Hurricanes or Superstorms flood the East Coast, we'll do it again. At some point we're going to have to stop having this same conversation about whether some deadly, destructive, and expensive event was related to climate change and start talking about what we're doing to address it.