Scientists find that stratospheric intrusions can increase the effects of Santa Ana winds on wildfires

This important research about a little known weather phenomenon that affects wildfires was conducted by government employees working for the National Oceanic and Atmospheric Administration (NOAA) and the University of Colorado at Boulder. However, to get a copy of this taxpayer-funded research, you will have to pay $38 to a private organization, John Wiley & Sons, Inc., a corporation that for the year that ended April 30, 2015 had $1.8 billion in revenue and a net income of $176 million. In that year, 64 percent of their revenue came from journal subscriptions.

While some government and university employees may be able to access this and other research papers, they can only do it because their employer pays tens or hundreds of thousands of dollars in subscription fees to these private companies. The employees can seamlessly read the papers, and don’t always realize that non-employees can’t.

Gowers Weblog has an exhaustive article about this issue in which he lists the exorbitant subscription fees paid by some universities in the United States.

He noted, for example, that the state universities in Arizona pay a total of $2.7 million to just one of these private outfits, Elsevier.

The authors of the paper are Andrew O. Langford (U. of Colo.), R. B. Pierce (NOAA), and P. J. Schultz (NOAA).

The University of Colorado and NOAA have graciously allowed this brief summary of the publicly-funded research to be released — to the public:

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Southern Californians and writers love to blame the hot, dry Santa Ana winds for tense, ugly moods, and the winds have long been associated with destructive wildfires. Now, NOAA researchers have found that on occasion, the winds have an accomplice with respect to fires, at least: Natural atmospheric events known as stratospheric intrusions, which bring extremely dry air from the upper atmosphere down to the surface, adding to the fire danger effects of the Santa Anas, and exacerbating some air pollution episodes.

Springs Fire
Satellite image of the smoke on 2 May 2013, the first day of the Springs Fire northwest of Los Angeles. The photo was taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA’s Terra satellite.

The findings suggest that forecast models with the capacity to predict stratospheric intrusions may provide valuable lead time for agencies to issue air quality alerts and fire weather warnings, or to reallocate fire fighting resources before these extreme events occur.

“The atmosphere could give us an early warning for some wildfires,” said Andrew Langford, a research chemist at NOAA’s Earth System Research Laboratory in Boulder, Colorado, and lead author of the study. Researchers at NOAA’s National Environmental Satellite, Data, and Information Service (NESDIS) and the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder coauthored the work, which was accepted for publication this week in the American Geophysical Union journal Geophysical Research Letters.

The authors took a detailed look at the May 2013 “Springs Fire” that burned 25,000 acres about 50 miles northwest of Los Angeles. The researchers used a NOAA forecast model that incorporates satellite observations of ozone, wind data, and other atmospheric information to detect the occurrence of the intrusions.

The analysis showed that in the early hours before the Springs Fire, a tongue of air characteristic of the stratosphere—extremely dry and very high in ozone from the stratosphere’s ozone layer—reached to the surface in southern California and extended as far south as Baja California.

The researchers found that ground-based monitoring stations near the fire’s origin also confirmed the telltale signs of the intrusion right before the fire broke out: A large drop in relative humidity and a rise in ozone. As the day went on, a combination of factors accelerated the fire: Low humidity, persistent high winds, dry condition of the grasses and other vegetation, clear skies and bright sunlight, and very warm surface temperatures. A few days later, cloudy skies, a drop in temperature, a shift in winds, and widespread rainfall helped extinguish the fire.

The stratospheric intrusion also had another downside during the Springs Fire: it added ozone from the upper atmosphere to the urban and fire-related pollution produced in the lower atmosphere. On the second and third days of the fire, this helped to push levels of ozone—which can harm people’s lungs and damage crops—over the federal ozone limit at 24 monitoring sites across southern California. Monitors as far away as Las Vegas also saw a spike in ozone on the third day of the fire. The observed exceedances of the ozone standard were unusual for the region for that time period, suggesting that the stratospheric intrusions were a contributing factor.

“Stratospheric intrusions are double trouble for Southern California,” said Langford. “We knew that the intrusions can add to surface ozone pollution. Now we know that they also can contribute to the fire danger, particularly during La Niña years when deep intrusions are more frequent, as recently shown by our NOAA colleagues at the Geophysical Fluid Dynamics Laboratory. The good news is that with models and observations, we can get an early warning from the atmosphere in some cases.”

The authors note that stratospheric intrusions have previously been implicated in the explosive development of wildland fires in New Jersey and Michigan, but have not previously been connected to fires in southern California or to the Santa Ana winds. The frequent occurrence of stratospheric intrusions above the west coast during the fall, winter, and spring suggests that similar circumstances may have played a role in other major southern California fires, including the series of destructive fires that burned more than 800,000 acres in October of 2003, and burned nearly a million acres in October of 2007, say the authors.

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(UPDATE July 12, 2015: We contacted one of the authors, Andrew Langford, and he sent us a copy of the paper, which has not been copyedited and typeset yet.)

Information about unrestricted online access (Open Access) to research funded by taxpayers.

Thanks and a tip of the hat go out to Barbara.

It was very dry in the far west and northwest during the first six months of 2015

Precipitation, January-June, 2015If the brown areas above have a hot and dry summer, wildland firefighters will be spending a lot of time over the next couple of months in California, Oregon, Idaho, and Montana.

And, those same areas were warmer than normal during the first half of 2015. Some were the warmest ever recorded for the period.

Temperature Jan-June 2015

I stopped trying to predict the nature of fire seasons a long time ago. Pre-season weather is a significant factor, but more important is the weather during the fire season. So ask me again in September how busy firefighters in the west will be this summer.

Precipitation, last 30 days — dry in the Northwest

Precipitation percent of normal, last 30 days
Precipitation percent of normal, last 30 days. July 6, 2015. NWS.

The National Weather Service Weather Prediction Center (@NWSWPC) distributed this image, and wrote:

The % of normal precip for the last 30 days. Much of the US has been wetter than seasonal average for June/early July.

And, some areas have been much drier than normal, including northern California, Oregon, Washington, Idaho, and northwestern Montana.

Lightning map, July 2, 2015

Lightning map July 2, 2015

The map, produced by Predictive Services at the National Interagency Fire Center, shows the location of lighting that was detected during the 24 hours ending at 6 a.m. MT, July 2, 2015.

Outlook for wildfire potential through October, 2015

The Predictive Services section at the National Interagency Fire Center has issued their Wildland Fire Potential Outlook for July through October. The data represents the cumulative forecasts of the ten Geographic Area Predictive Services Units and the National Predictive Services Unit.

If their forecasts are accurate, the three west coast states and the western portions of Idaho, Nevada, and Montana will have above normal wildfire activity into October.

Here are the highlights from their outlook.

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July

Wildfire Outlook, July, 2015

– Higher than usual temperatures; minimal summer precipitation; and already dry fuels will combine to continue above normal potential across most of the pacific coast states, as well as the northern Rocky Mountains and northern and western Great Basin.

– Fuels that were exposed to drying earlier than usual as well as hot and dry conditions throughout May and June have led to above normal potential throughout Alaska.

– Abundant spring and early summer precipitation and moist fuels will alleviate much of the fire concern for the Rocky Mountains, Southwest, and areas east of the Mississippi.

August

Wildfire Outlook, August, 2015

– Much of the above normal area from July will linger into August, with the exception of some of northern California. Above normal conditions will spread slightly westward to encompass more of the Great Basin.

– Most of the areas experiencing below normal potential will return to a more normal condition, with only some of the Central Rockies and Ohio Valley below normal.

September through October

Wildfire Outlook, September October, 2015

– Almost all of the above normal potential will return to normal through this period, leaving only far southern California as above normal.

– Below normal fall conditions will develop across inland portions of the southeast.

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UPDATE: And, as a bonus, here is the Drought Monitor that was released July 2, 2015. Portions of California, Nevada, and Oregon are in Extreme or Exceptional Drought. Nine of the eleven western states have areas in Severe Drought or worse.

Drought Monitor June 30, 2015

Record heat in the west may be followed by dry lightning

lightning near hot springs, sd
Lightning near Hot Springs, South Dakota, July 23, 2012. Photo by Bill Gabbert.

(UPDATED at 3:46 p.m. MT, June 24, 2015)

Isolated Thunderstorms

Isolated dry thunderstorms (with little or no rain) are predicted for some areas in northeastern California, western Nevada, and central Oregon Friday and into early Saturday morning. Land managers are worried about the possibility of new lightning-caused wildfires.

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(Originally published at 9:59 a.m. MT, June 24, 2015)

Forecasters with the National Weather Service have published Special Weather Statements with warnings about extreme heat and lightning predicted for northern California, Oregon, and Washington beginning Thursday and through the weekend.

This interesting period will start with near-record, and record-setting heat on Thursday and Friday with high temperatures of 100 to 112 degrees in the valleys. Thunderstorms will be thrown into the equation starting on Friday, initially with little rainfall, raising the possibility for dry lightning. Later in the weekend there will be more moisture with the storms.

 

Spring was the 11th wettest and warmest for the United States

Spring precipitation

The United States continues to experience unusual weather. The three months of March, April, and May (spring) were the 11th wettest spring for the contiguous USA according to @NOAANCEIclimate, while it was the 11th warmest spring for the contiguous U.S.

Spring temperatures

Climate anomalies, May and Spring, 2015
(click to enlarge)

Wildfire potential, June through September

The Predictive Services section at the National Interagency Fire Center has issued their Wildland Fire Potential Outlook for June through September. The data represents the cumulative forecasts of the eleven Geographic Area Predictive Services Units and the National Predictive Services Unit.

If their predictions are accurate, portions of California, Washington, Oregon, and Arizona will have expanding areas of above normal wildfire potential in June and July

Here are the highlights from their outlook.

June

wildfire June outlook

  • Moisture across the West has reduced the Above Normal areas to central California and southwestern Arizona.
  • Drier areas in the Northern Rockies, Northwest and the Southeast will begin to transition to Above Normal.
  • Above Normal conditions with continue in Alaska’s eastern Interior and most of Hawaii.
  • Below Normal fire potential covers much of the central U.S. after prolonged heavy rains.

July

wildfire July outlook

  • Above Normal fire potential will spread into the Northwest, the Northern Rockies and the Great Basin.
  • Above Normal fire potential will continue across central and southern California, southwestern Arizona, and spread into the Nevada Sierra Front. Hawaii will also remain in Above Normal potential.
  • Above Normal fire potential will expand through Georgia and the Carolinas while most of the central U.S. and Alaska will return to normal seasonal conditions.

August and September

wildfire August September outlook

  • Above Normal fire potential will continue across the Northwest, the Northern Rockies, the Great Basin and parts of central and southern California, and Hawaii.

And from NOAA and the USDA:

Drought Monitor US, May 26, 2015

 

Drought outlook, June, 2015