Pyrocumulus cloud near Timbarra, Victoria

Pyrocumulus Australia wildfire bushfire
Pyrocumulus north of Timbarra, Victoria, Australia. Murray King took the photo 30km west of the fire in Bindi, East Gippsland on January 25, 2019 at 5:30 p.m.

Murry King sent us this photo of the pyrocumulus cloud over a bushfire north of Timbarra, Victoria, Australia. He got the shot from a point 30km west of the fire in Bindi, East Gippsland on January 25, 2019 at 5:30 p.m.

Thanks Murry.

Here is the latest information about the fire from Vic Emergency:

This Advice message is being issued for Timbarra, Gillingall, Gelantipy, Butchers Ridge, W-Tree, Murrindal, Buchan and Buchan South.

There is an active bushfire north of Timbarra and Gillingall and west of the Gelantipy Road between Butchers Ridge and W-Tree that is not yet under control.

We have now started igniting a back burn on the south eastern corner of the fire near W-Tree, along Hodges Track and Dawson Track. If conditions are favourable, we will continue to extend the back burn later today.

There will be increased smoke in this area. Crews and machinery continue to strengthen containment lines around the fire perimeter.

Here is another photo of the pyrocumulus taken around the same time.

Massive pyrocumulus cloud over Australian bushfire produces hundreds of lightning strikes

Timbarra bushfire
Massive pyrocumulus cloud over a bushfire north of Timbarra, Victoria, Australia. TRFM photo.

Extreme heat on Friday in Victoria, Australia combined with strong winds and low humidity caused a bushfire 10 km (6 miles) north of Timbarra to grow from 300 hectares (740 acres) to approximately 10,522 hectares (26,000 acres). Lighting ignited the fire on January 16 and in an odd twist, extreme fire behavior Friday created hundreds of lightning strikes around a massive pyrocumulus cloud that rose to 38,000 feet while igniting additional fires.

The temperature at the top of the cloud was -55°C (-67°F) according to the Victoria Bureau of Meteorology.

Friday evening the weather changed substantially, bringing in cool, moist air that slowed the spread of the fire. Officials say due to the size and difficult topography, it will be weeks before it can be completely contained.

Smoke produced by large wildfires can be equal to a volcano

Above: Satellite photo taken August 2, 2017 showing smoke from some of the wildfires in British Columbia. The red dots represent heat detected by a sensor on the satellite.

It is not easy to measure and quantify the composition of the smoke and the amount of particulate matter that a huge wildfire produces when intense, large-scale burning forms towering pyrocumulus clouds that climb tens of thousands of feet into the sky. This launches the byproducts of combustion into the  stratosphere — the second layer of Earth’s atmosphere, above the troposphere. Once introduced at that level they have been tracked while circling the planet multiple times.

Below is an excerpt from an article by Megan Gannon at Live Science, which points out similarities between large wildfire events and volcanos.

For comparison, the explosive 2008 eruption of Mount Kasatochi, an island volcano in Alaska, sent about 0.7 to 0.9 teragrams (nearly 1 million tons) of aerosols — tiny, suspended particles — into the stratosphere, Peterson said. For months afterward, people around the Northern Hemisphere documented unusually colored sunsets, thanks to the sulfate aerosols and ash the volcano injected into the atmosphere.

Peterson’s team estimated that the British Columbia pyroCb event sent about 0.1 to 0.3 teragrams (about 200,000 tons) of aerosols into the stratosphere — which is comparable to the amount seen with a moderate volcanic event, and more than the total stratospheric impact of the entire 2013 fire season in North America, he said.

It’s well known that catastrophic volcanoes can influence the global climate. The huge 1991 eruption of Mount Pinatubo in the Philippines, one of the largest in living memory, lowered temperatures around the world by an average of 0.9 degrees Fahrenheit (0.5 degrees Celsius).

As an example of the wildfire activity in British Columbia last year, here is an excerpt from an article posted August 9 at Wildfire Today:

The wildfire situation in British Columbia has not gotten any better in the last several days. Currently there are 128 active wildfires in the province, with four of them being larger than 50,000 hectares (123,000 acres). The largest, the Hanceville Riske Creek Fire, is getting closer to half a million acres each day.

Since April 1, approximately 591,280 hectares (1,461,082 acres) have burned in 900 fires in BC.

  • Hanceville Riske Creek, 172,000 hectares (425,000 acres) approximately 60 km southwest of Williams Lake.
  • Elephant Hill, 117,000 hectares (289,000 acres), near Ashcroft.
  • Tautri Lake, 76,000 hectares (188,000 acres), 80 km northwest of Williams Lake.
  • Baezaeko River-Quesnel West, 53,000 hectares (131,000 acres).

More than 400 additional firefighters from Australia, New Zealand, Mexico and the US are expected to arrive in BC this week. Other firefighters from Australia have been in the province for a couple of weeks. More than 100 firefighters arrived from Mexico since Saturday of last week…

 

Pyrocumulonimbus clouds

Above: Bureau of Meteorology, Australia

(Originally published at 11:38 a.m. MST January 11, 2017)

The Australian Government’s Bureau of Meteorology has an excellent article about clouds that can form over rapidly burning vegetation fires. Pyrocumulus clouds can develop into pyrocumulonimbus that can generate lightning miles away from the fire.  Below are excerpts from the article.


What are pyrocumulonimbus clouds?

They’re a thunderstorm that forms in the smoke plume of a fire (or nuclear bomb blast, or volcanic ash cloud). In Australia they most commonly form in large and intense bushfire smoke plumes. (The official name for clouds that form this way is ‘flammagenitus‘, but they’re commonly known as pyrocumulonimbus.)

How do they form?

The intense heat from the fire causes air to rise rapidly in the smoke plume. The rising hot air is turbulent and draws in cooler air from outside the plume, which helps cool the plume as it rises. As the plume rises to higher and higher elevations the atmospheric pressure reduces, causing the plume air to expand and cool even further. If it cools enough, the moisture in the plume air will condense and forms cumulus cloud, which, because it comes from the fire plume, we call ‘pyrocumulus’. The condensation process causes latent heat to be released, which makes the cloud warmer and more buoyant and causes the cloud air to accelerate upwards. Further expansion and cooling causes more moisture to condense and the cloud air to accelerate upwards even more. In the right conditions the cloud can accelerate into the lower stratosphere before losing buoyancy. Collisions of ice particles in the very cold upper parts of these clouds cause a build-up of electrical charge, which is released by giant sparks—lightning. Having produced a thunderstorm, the cloud is now known as ‘pyrocumulonimbus’.

Thunderstorm initiated by a wildfire

This time-lapse video of the pyrocumulus cloud over the Sedgerly Fire in Queensland, Australia is fascinating. According to the description by the Bushfire Convective Plume Experiment it shows a thunderstorm initiated by the fire. If you look closely you will see rain and lightning.

Impressive convection column on Pioneer Fire is being studied by researchers

Above: The photo above was taken from the research aircraft August 30 by Nick Guy of the University of Wyoming’s Atmospheric Science department.

The Fire Weather Research Laboratory from San Jose State University is conducting research from an aircraft flying over the Pioneer Fire in central Idaho. Today using N2UW, a twin engine 1977 Beech 200T King Air, they flew for over three hours at 27,000 feet studying the fire for the RaDFire project.

The aircraft is outfitted with a ton of instruments including Doppler radar. Craig Clements, Associate Professor in the Meteorology Dept. at SJSU, described it for us:

The radar is called the Wyoming Cloud Radar (WCR). It’s on the aircraft, points up, down, and down-forward to get horizontal winds and vertical winds. The goal of the RadFIRE (Rapid Deployments to Wildfires Campaign) is to get data on plume dynamics from ground based mobile Doppler Lidar. But we were awarded 10 flight hours to test the WCR to see if it works in smoke plumes. And it does so well, more than we can imagine!

The group has been known to fly through the convection column. I’ve done that a few times and it’s an interesting experience — it can get a little turbulent, as you might expect.

On Monday they said the top of the pyrocumulus cloud over the fire topped out above 30,000 feet. In Tuesday’s photos it was at about 25,000 feet but toward the end of the day the top got up to at least 32,000 feet, Mr. Clements said.

The project is sponsored by the National Science Foundation and it’s being led by San Jose State University. Other collaborators on the project are David Kingsmill at the University of Colorado Boulder, and the University of Wyoming King Air team.

Since it started on July 18 the Pioneer Fire has burned over 140,000 acres.

This last photo of the convection column was not taken by the researchers. It was shot by Steve Botti in Stanley on August 29, more than 20 miles away from the fire.

Pioneer Fire
Pioneer Fire, as seen from Stanley August 29, 2016. Via Mike Warren.