News and opinion about wildland fire
Author Bill GabbertPosted on Categories Uncategorized3 Comments on Therapy dogs visit firefighters at the Soberanes Fire Two therapy dogs visited firefighters at the Soberanes Fire south of Monterey, California over the weekend. The dogs are more commonly seen at hospitals, but they lifted the spirits of the firefighters who had not been home for one or two weeks
“When you see your guys smiling and they’re tired – they worked really hard yesterday – but they got time to come over and play with the dogs. It’s kind of neat,” said Santa Barbara firefighter Jim McCoy.
The images are screenshots from an ABC7 video.
The National Weather Service has posted Red Flag Warnings or Fire Weather Watches for areas in Idaho, Montana, Wyoming, and Utah.
The Red Flag map was current as of 9:10 a.m. MDT on Tuesday. Red Flag Warnings can change throughout the day as the National Weather Service offices around the country update and revise their forecasts and maps. For the most current data visit this NWS site.
Author Bill GabbertPosted on Categories Uncategorized1 Comment on Scientists discover a new kind of fire whirl The “blue whirl” can greatly reduce pollution
Above: A “blue whirl”.
Scientists attempting to develop a new method for mitigating oil spills by burning the oil were hoping to find a way to reduce the air pollution as the petroleum product burns. We’ve all see the thick, black smoke at an oil fire. They may be a step closer to their goal with the discovery of a new type of fire behavior — a previously unseen type of flame. They call it a “blue whirl”.
A paper published online August 4, 2016, in the peer-reviewed journal Proceedings of the National Academy of Sciences describes this previously unobserved flame phenomenon.
A yellow flame is a sign of very incomplete combustion and produces more particulates and air pollution than a blue flame like you see on a gas fueled stove.
So far they have only created the blue whirl in a chamber which has slits in the side that cause the air to rotate as it enters. Over a layer of water they injected a liquid fuel, n-heptane, and then ignited it. The flame at first is yellow but eventually transitions to a small, swirling blue flame.
“Blue whirls evolve from traditional yellow fire whirls. The yellow color is due to radiating soot particles, which form when there is not enough oxygen to burn the fuel completely,” said Elaine Oran, Glenn L. Martin Institute Professor of Engineering and co-author of the paper. “Blue in the whirl indicates there is enough oxygen for complete combustion, which means less or no soot, and is therefore a cleaner burn.”
“This is the first time fire whirls have been studied for their practical applications,” said Michael Gollner, co-author of the paper and assistant professor of fire protection engineering at the A. James Clark School of Engineering at the University of Maryland.
One of the principles that reduces the pollution in the blue whirl is that plenty of oxygen is available for the fuel, helping it to burn more completely. Another is that the partially burned fuel remains in the flame longer, burning more completely.
Land managers sometimes use an “air curtain” to burn woody debris from fuel reduction operations. We wrote about this in 2013 after visiting one near Custer, South Dakota. The one we saw was trailer-mounted. The key to the system is pumping large amounts of compressed air into the fire box or open trench. Some of the devices create a vortex which traps the particulates keeping them in the burn zone longer, causing them to more completely burn while reducing their size and the visible smoke.
Some oil spill remediation techniques include corralling the crude oil to create a thick layer on the water surface that can be burned in place, but the resulting combustion is smoky, inefficient, and incomplete. However, the Clark School researchers say blue whirls could improve remediation-by-combustion approaches by burning the oil layer with increased efficiency, reducing harmful emissions into the atmosphere around it and the ocean beneath it.
“Fire whirls are more efficient than other forms of combustion because they produce drastically increased heating to the surface of fuels, allowing them to burn faster and more completely. In our experiments over water, we’ve seen how the circulation fire whirls generate also helps to pull in fuels. If we can achieve a state akin to the blue whirl at larger scale, we can further reduce airborne emissions for a much cleaner means of spill cleanup,” explained Gollner.
Beyond improvements to fuel efficiency and oil spill remediation, there are currently few easy methods to generate a stable vortex in the lab, so the team hopes their discovery of the ‘blue swirl’ can serve as a natural research platform for the future study of vortices and vortex breakdown in fluid mechanics.
“A fire whirl is usually turbulent, but this blue whirl is very quiet and stable without visible or audible signs of turbulence,” said Huahua Xiao, assistant research scientist in the Clark School’s Department of Aerospace Engineering and corresponding author of the paper. “It’s really a very exciting discovery that offers important possibilities both within and outside of the research lab.”
These photos have been moved, and the article now includes a description of two days in the life of Jeff Zimmerman, the wildfire photographer, as he took the photos.
Author Bill GabbertPosted on Categories Uncategorized2 Comments on The spread of the Pilot Fire slows The fire is burning near Crestline between Silverwood Lake and Lake Arrowhead in southern California.
Above: A retardant-coated truck near the Pilot Fire, August 7, 2016. Photo by Jeff Zimmerman. More Pilot Fire photos.
(UPDATED at 8:16 a.m. PDT August 10, 2016)
The Pilot Fire near Crestline, California did not grow as much Tuesday as it had in previous days. A mapping flight at 1:30 a.m. Tuesday determined it had burned 7,522 acres. Wednesday morning the incident management team reports it is now at 7,861 acres.
Many incident management teams pull out of the air a grossly understated “containment” figure (which is the reason we rarely include that statistic), but Dave Bently, a spokesperson for the fire, said the fire is 64 percent contained, meaning in this case, he said, that they have a fireline around 64 percent of the perimeter. Which, by the way, is the definition of fire containment. Kudos to the team for making the containment number meaningful.
The map of the fire shows the fire perimeter from the Tuesday morning mapping flight, plus heat detected since then by a satellite. From 200 miles above the Earth the sensor only detects large heat sources, so there are likely many more small hot spots. But it is significant that all of the heat sources found are within or very close to the earlier perimeter. The accuracy of the satellite-detected data is supposed to be within 375 meters (1,230 feet). Scroll down to see other maps.
The numbers:
The incident management team has posted information on InciWeb about evacuations, road closures, trail closures, smoke, and drones, all of which are important, but there is not a lot of information about the fire itself such as the fire activity over the last 24 hours, where it was still spreading, what firefighters are doing, the use of aircraft, and where the open fireline is. Mr. Bently said that information was not available but should be later in the day.
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(UPDATED at 6:55 a.m. PDT August 9, 2016)
The Pilot Fire north of Crestline, California continued to be active Monday on the west and south sides. The incident management team is calling it 6,963 acres.
At least 5,200 homes are under voluntary or mandatory evacuation orders.
Author Bill GabbertPosted on Categories Uncategorized10 Comments on Soberanes Fire continues to march through the mountains above Big Sur 
For 16 days the Soberanes Fire has spread through the Santa Lucia Mountains that rise abruptly from the Pacific Ocean above Big Sur. Since we last wrote about the fire on August 2 the fire has grown from 43,000 to 57,845 acres. There have been no reports of additional homes burned since it was announced five days ago that 57 residences and 11 outbuildings had been destroyed. Another three homes have been damaged.
Since starting from an illegal campfire, the blaze has been moving through very steep, rugged, inaccessible terrain. Several areas are under evacuation orders.
It has burned to within 1.2 miles of Big Sur on Highway 1, and is 15 miles west of US 101. It has not crossed US 101 and at its closest point is about 1,000 feet from the highway.
