Tag Archives: fire

A new study on biomass fuel says smoke is more damaging to lungs than we assumed

Biomass cooking fires can incur “considerable damage” to the lungs of people who use them, a new study reveals. This effect is caused by “dangerous concentrations” of pollutants and bacterial toxins released during the burning of plant matter.

A biomass-fueled kitchen of one of the participants.

Roughly 3 billion people the world over still use biomass fuel for cooking, such as dry brush. This is making a significant contribution to the number of deaths related to household air pollution — an estimated 4 million annually. Governments around the world have launched projects to support the transition towards cleaner cooking fuels, such as liquefied petroleum gas, but economic and social factors, alongside faulty education on the benefits of this transition, means that many fires still burn on wood or brush.

Smokey issues

“It is important to detect, understand and reverse the early alterations that develop in response to chronic exposures to biomass fuel emissions,” said study co-author Abhilash Kizhakke Puliyakote, Ph.D., a postdoctoral researcher from the University of California San Diego School of Medicine.

The team used computer tomography scanners to analyze the lungs of 23 people who cook with wood biomass fuels or liquefied gas from Thanjavur, India. They also took air samples from their homes (which they used to measure pollutant concentrations there) and studied the lung function of the participants through traditional testing methods (such as spirometry). The scans were used to make quantitative measurements, so the team would, for example, take a scan when a person inhaled and another one when they exhaled, so they could measure the difference.

All in all, those who cooked with wood biomass were routinely exposed to higher levels of pollution and bacterial endotoxins. They also showed a much higher quantity of air trapping in their lungs, which is associated with lung diseases. Among the group, some participants had very high levels of air trapping and also showed abnormal tissue mechanics in their lungs, even when compared to their peers. This subgroup (around 30% of all biomass-burners) had more than 50% of the air they inhaled ending up trapped in their lungs.

“Air trapping happens when a part of the lung is unable to efficiently exchange air with the environment, so the next time you breathe in, you’re not getting enough oxygen into that region and eliminating carbon dioxide,” Dr. Kizhakke Puliyakote said. “That part of the lung has impaired gas exchange.”

“This increased sensitivity in a subgroup is also seen in other studies on tobacco smokers, and there may be a genetic basis that predisposes some individuals to be more susceptible to their environment”.

Smoke tended to affect the small airways of the lungs of participants, the authors explain, although the exact process is not yet clear. The study focused on cooking and biomass-fueled fires, but the findings are applicable to smoke from any source. Furthermore, the authors say that conventional testing has underestimated just how damaging smoke is to the lungs.

“The extent of damage from biomass fuels is not really well captured by traditional tests,” Dr. Kizhakke Puliyakote said. “You need more advanced, sensitive techniques like CT imaging. The key advantage to using imaging is that it’s so sensitive that you can detect subtle, regional changes before they progress to full blown disease, and you can follow disease progression over short periods of time.”

It is “crucial” for anyone who is exposed to biomass smoke for any extended duration to have a complete assessment of lung function by healthcare professionals to ensure that any potential injury can be resolved with appropriate interventions,” he adds. With the blaze of wildfires we’ve seen this year, this probably means that many, many people need to get their lungs checked.

The findings have been presented at RSNA 2020 – Radiological Society of North America Annual Meeting in Chicago.

California fires break new record as residents are evacuated across the state

Wildfires in California have already broken a state record with still two months to go of the wildfire season, burning more than two million acres (809.000 hectares). Residents are being forced to leave their homes as firefighters try to contain blazes across the state.

Credit US Department of Agriculture Flickr (CC BY 2.0)

The previous record was set in 2018, with 1.96 million acres (793.184 hectares) burned, according to the California Department of Forestry and Fire Protection (Cal Fire) which began taking records in 1987. Lynne Tolmachoff, the spokeswoman for Cal Fire, said there were surprised over how early in the season the record was set.

“In the past 33 years we have not seen a single year go over two million acres. This is definitely record-breaking and we have not even come close to the end of fire season yet,” said Tolmachoff in a press release. “It’s a little unnerving because September and October are historically our worst months for fires.”

At least seven people have died as a result of this year’s fires and some 3,800 structures have been damaged or destroyed, according to figures provided by Cal Fire. More than 14,100 firefighters were battling 24 different wildfires as of yesterday, the fire department said on its social media.

Firefighters are struggling to enclose several dangerous blazes, with dry and hot winds expected in the next few days that could increase the fire danger to critical levels. Authorities have ordered the evacuation of more mountain communities as the largest blaze, the Creek Fire, expands in the Sierra National Forest.

The Creek Fire started on Friday in steep and rugged terrain and since then has spread to 78,790 acres (31.8 hectares), with 0% being contained, according to Cal Fire. At least a dozen dwellings were burned in the town of Big Creek, with over 200 hikers having to be airlifted after being trapped by the flames at the Mammoth Pool reservoir.

Cal Fire said a “smoke-generating pyrotechnic device, used during a gender reveal party” started The El Dorado fire in San Bernadino County. These are celebrations announcing whether expecting parents are going to have a girl or a boy. In recent years, several of them have gone wrong, even causing the death of a woman in 2019.

“Cal Fire reminds the public that with the dry conditions and critical fire weather, it doesn’t take much to start a wildfire”, a tweet by Cal Fire reads. People who cause fires “can be held financially and criminally responsible,” it added. California has seen nearly 1,000 wildfires since 15 August, often started by lightning strikes.

The fire conditions were aggravated by record temperatures registered over the three-day Labor Day weekend, stressing the already exhausted firefighters. A record 49 degrees Celsius (121 Fahrenheit) was registered on Sunday in Woodland Hills, an all-time high for Los Angeles County, the National Weather Service said.

High temperatures have led to the highest demand for power so far this year, according to California Independent System Operator, which manages the state’s power grid. The state could see power outages soon if residents don’t reduce their electricity usage, the company warned, although none has yet taken place.

The Arctic sees record heatwave amid forest fires. What does it mean for the world?

The Arctic is currently going through a severe heatwave, with temperatures recently reaching a record of 38 degrees Celsius (100.4 degrees Fahrenheit), on the backdrop of expanding forest fires. In response, scientists have raised the alarm, warning over the acceleration of global warming.

Credit Wikipedia Commons

The record-high temperature was registered in the city of Verkhoyansk, Russia. But the Siberian town isn’t alone. Much of Russia has recently been dealing with a heatwave, with multiple locations reporting temperatures as high as 45 degrees Celsius (113 degrees Fahrenheit).

“Apparently, this particularly region of eastern Siberia has very, very cold extremes in winter, but is also known for its extremes in summer, so temperatures above 30 degrees Celsius in July are not unusual,” World Meteorological Organization spokeswoman Clare Nullis said in a statement. “but obviously 38 degrees Celsius is exceptional.”

The surprising hot weather was also registered in other parts of the Arctic such as northern Canada and Scandinavia. Meteorologists agree it is part of a pattern seen this year of higher temperatures in usually cool areas of the world. This type of weather stands to have global consequences and foreshadows the future of the Arctic.

Russia is emerging from its hottest winter on record, and since the beginning of the year, temperatures have averaged 12.4 degrees Fahrenheit above what’s typical in Siberia. And this polar heat has led to a string of woes for the region, from a major oil spill stemming from thawing permafrost to early wildfires north of the Arctic circle.

More than four million hectares of forests in Siberia were on fire last August, according to Greenpeace. This year the fires have already started raging much earlier than the usual start in July, said Vladimir Chuprov, director of the project department at Greenpeace Russia.

Persistent warm weather in the Arctic coupled with wildfires can cause the permafrost to melt faster. This would exacerbate global warming by releasing growing amounts of methane, a strong greenhouse gas, Katey Walter Anthony, an expert on methane release from frozen Arctic soil, told AP.

“Methane escaping from permafrost thaw sites enters the atmosphere and circulates around the globe,” Anthony said. “Methane that originates in the Arctic does not stay in the Arctic. It has global ramifications.”

And what happens in the Arctic can even alter the weather in the United States and Europe. The unusual warming can reduce the temperature and pressure difference between the Arctic and lower latitudes where more people live, Judah Cohen, a winter weather expert, told AP.

Meteorologists at the Russian weather agency Rosgidrome said a combination of factors can explain the temperature spike in the Arctic. “The ground surface heats up intensively, the nights are very warm, the air doesn’t have time to cool and continues to heat up for several days,” said Marina Makarova, chief meteorologist.

Researchers said the spike is indicative of a much bigger global warming trend. “The key point is that the climate is changing and global temperatures are warming,” Freja Vamborg, senior scientist at the Copernicus Climate Change Service in the U.K, told AP. “We will be breaking more and more records as we go.”

The key to avoiding massive wildfires? Small, strategic controlled fires

As climate change continues to take its toll, more intense wildfires are expected. A team of researchers believes they have a way to tackle this phenomenon — but the solution is wildly unpopular.

“We need a colossal expansion of fuel treatments,” said study lead author Rebecca Miller, one of the study authors said.

US Forest Service prescribed burn in California’s Sierra National Forest. Image credits: US Forest Service.

Fuel and fire

Wildfires have always been devastating. They’re a natural phenomenon in many parts of the world, but deforestation and climate change are making things much worse, exacerbating fires way beyond their normal levels.

Not only is climate change driving drought, but it’s making things drier. This means that many plants, which are usually moist and would not readily burn have become fuel, spreading the fire and making it more powerful than it would naturally be.

The effect of this extra fuel has become apparent in the catastrophic Australia bushfires, which have already burned an estimated 18.6 million hectares (46 million acres), destroying some 5,900 buildings and killing 30 people and over 1 billion animals.

Now, the authors of a new study published in Nature Sustainability believe they have found a way to limit the effect of such fires. The study was focused on the California area but could apply to other drought-plagued areas, including Australia.

Essentially, they say that proactive vegetation treatment (which includes small, controlled fires) can substantially reduce the total burned area. Although this seems dangerous, it can reduce the amount of fuel available for uncontrolled fires.

“Prescribed burns are effective and safe,” said study co-author Chris Field, the Perry L. McCarty Director of the Stanford Woods Institute for the Environment and Melvin and Joan Lane Professor for Interdisciplinary Environmental Studies. “California needs to remove obstacles to their use so we can avoid more devastating wildfires.”

Fire suppression efforts in California have been somewhat successful, but they’ve also led to a massive accumulation of wood and plant fuel in forests. This means that when a fire does go out of control, it can grow to terrifying strengths.

The controlled burns, especially in conjunction with vegetation thinning, have multiple effects. They provide the same environmental benefits as natural fires (such as reducing the spread of insects and increasing species diversity) and rarely escape beyond the confined area.

To make a significant difference, California needs to deploy treatments on nearly 20% of the state’s land area, the study finds — be it controlled fires or vegetation thinning. California is already deploying ambitious fire control measures, but the recommended measures are even more ambitious.

A rewarding but unpopular solution

Controlled fires are unpopular, but they can make a positive difference. Image credits: USDA.

The problem, however, is that no one really wants to do controlled fires anymore. Researchers carried out interviews with policymakers and government employees, finding that everyone is extremely risk-averse, taking decisions in the shadow of liability laws — burners would be held responsible for every fire that escapes the controlled area, even if the net effect is positive. The system works in a counterproductive way, researchers found.

Essentially, federal employees don’t get any reward if the prescribed burns are successful and reduce burn area, but are heavily punished for any accident regarding escaped fires. So you can have a situation where the net area of the fires is reduced, but where one controlled fire caused minor, unanticipated damage — and the employees would still be sanctioned

To make matters even more touchy, negative public opinion also places more pressure on federal agencies, making the approach even more undesirable.

Controlled fires are almost a traditional solution, but they’ve become less and less popular. Deploying this approach would require quite a bit of innovation — if not on the technical side, then definitely on the legislative and organizational side. Essentially, agencies need to reorganize and be capable of handling the risks, especially when they are heavily outweighed by positive outcomes. This also needs to be communicated effectively so that public opinion understands the general picture and what is at stake.

We can only hope that policymakers can make the right decision and implement these changes. It’s not an easy task, but it can be done. With climate change coming into force, this is more important than ever.

“As catastrophic climate impacts intensify, societies increasingly need to innovate to keep people safe,” said study co-author Katharine Mach, an associate professor at the University of Miami who was director of the Stanford Environment Assessment Facility and senior research scientist in the Stanford School of Earth, Energy & Environmental Sciences at the time of the research. “Much of this innovation is conceptually simple: making sure the full portfolio of responses, prescribed burns and beyond, can be deployed.”

The study has been published in Nature Sustainability.

Humans figured out how to start fires way sooner than expected

Let’s be honest for a second here — we say humans ‘mastered’ fire, but most of us wouldn’t be able to light something up without some matches to save our lives.

Image credits Gerd Altmann.

It’s understandable, then, for researchers to assume that early humans likely harvested (instead of starting) fires. However, the ability to harness fire was a key developmental step for our species, enabling us to cook, protect ourselves from wildlife, or just by making the cave a more enjoyable place to hang around in. As such, archeologists are very keen (and eager to debate on) when exactly we learned to start fires.

New research from an international team now reports that Neanderthals, one of our ancient (and now extinct) relative species knew how to produce fire, overturning our previous assumptions.

Baby light my fire

“Fire was presumed to be the domain of Homo sapiens but now we know that other ancient humans like Neanderthals could create it,” says co-author Daniel Adler, associate professor in anthropology at the University of Connecticut (UConn). “So perhaps we are not so special after all.”

The team drew on hydrocarbon and chemical isotope analysis, archeological evidence of fire use, and models of the Earth’s climate tens of thousands of years ago to show that our ancient cousins did indeed know how to light a fire. The study focused on the Lusakert Cave 1 in the Armenian Highlands.

The team analyzed sediment samples to determine the level of polycyclic aromatic hydrocarbons (PAHs) — compounds that are released by burning organic materials. Light PAHs disperse widely, the team explains, and are indicative of wildfires. Heavy PAHs, on the other hand, spread narrowly around a source of fire.

“Looking at the markers for fires that are locally made, we start to see other human activity correlating with more evidence of locally-made fire,” says lead author Alex Brittingham, a UConn doctoral student in anthropology.

Higher levels of heavy PAHs at the site (which indicate regular fire use) correlate with evidence of increased human occupation (such as dumps of animal bones from meals) and of tool making, the team explains.

In order to rule out the possibility that these fires started naturally (for example, following lightning strikes), the team analyzed hydrogen and carbon isotope ratios in plant waxes preserved in sediment from those ancient days. This step is useful for recreating the kind of climate the plants grew in, the team reports. All in all, they didn’t find any link between the paleoclimatic conditions at the time and the chemical evidence left over by the fires. The inhabitants were not living in drier, wildfire-prone conditions while they were utilizing fires within the cave.

“In order to routinely access naturally caused fires, there would need to have been conditions that would produce lighting strikes at a relative frequency that could have ignited wildfires,” says Michael Hren, study author and associate professor of geosciences.

In fact, the team reports that there were fewer wildfires going on in the area while humans inhabited the cave (light PAH frequency was low while heavy PAH frequency in the cave was high). This finding suggests that the Neanderthals acted as a kind of fire control in the area they inhabited, intentionally or not. It also shows they were able to control (i.e. start) fire without having to rely on natural wildfires.

The team now plans to expand their research to other caves occupied by early humans, to determine whether different groups learned to control fire independently of people in other geographic areas. In other words, was it something that only certain groups figured out, or more wide-spread knowledge?

The paper “Geochemical Evidence for the Control of Fire by Middle Palaeolithic Hominins” has been published in the journal Scientific Reports.

New gel-like material can stop wildfires for months at a time

New research at Stanford aims to gel out wildfires.

Image credits Marc Mooney.

A novel preventive technique developed at Stanford could help slash the incidence and severity of wildfires. The technique involves an environmentally-benign gel that helps common fire-retardants applied against wildfires to last longer.

Up in smoke

“This has the potential to make wildland firefighting much more proactive, rather than reactive,” said Eric Appel, the study’s senior author and an assistant professor of materials science and engineering at Stanford.

“What we do now is monitor wildfire-prone areas and wait with bated breath for fires to start, then rush to put them out.”

The idea behind the gel is to apply it to areas that are prone to wildfires. The gel helps fix fire-retarding compounds where they’re needed long after weathering would remove them by themselves. The team notes that the gel treatment is more effective and much less expensive than monitoring and sending firefighters in to contain the wildfires.

We’ve done a pretty decent job at suppressing wildfires over the last century or so since the industrial revolution really picked up. The downside to this, however, is that it makes wildfires today more likely to happen due to fuel (dry plant matter) buildup. Fire is a natural part of many ecosystems, and helps recycle nutrients and clear the way for new generations of plants and animals to move in after the scorch. Today, the issue of wildfires is further intensified by shifts in precipitation levels and climate.

The last two years recorded four of the 20 largest and eight of the 20 most destructive wildfires in California’s history, even though the 2019 season has been relatively calm in the West, the team explains. They add that federal spending on firefighting in 2018 drained over $3 billion.

Image credits Anthony C. Yu et al., 2019, PNAS.

Despite their ecological role, most wildfires in the U.S. are caused by people, and many originate in the same hotspots. These include roadsides, camping grounds, and remote electrical lines. The team’s idea was to treat these at-risk areas ahead of time to prevent wildfires — but we didn’t have any long-lasting, environmentally-benign materials to use for the task.

Wildfire preventive measures today revolve mostly around the clearing of potential fuel, and short-term suppressants and fire retardants. If a wildfire starts, firefighters use suppressants, such as gels that carry water and wet superabsorbent polymers (the stuff that’s in diapers). They’re currently short-lived, however, and lose effectiveness in about an hour as they dry out. Crews thus use such gels to protect buildings in the path of the fire for example, rather than blanketing the whole forest with them.

The Stanford team wanted to improve this useful time, so they swapped the traditional formulation (which uses ammonium phosphate or its derivatives) for a cellulose-based substance. This swap made the gel stay on vegetation longer even when exposed to wind, rain, and other environmental factors. The substance is non-toxic, made from materials used in food, drug, cosmetic, and agricultural products. Application is as simple as loading it into standard agricultural spraying equipment or an airplane and spraying it on or around a point of interest.

“You can put 20,000 gallons of this on an area for prevention, or 1 million gallons of the traditional formulation after a fire starts,” said study lead author Anthony Yu, a Ph.D. student in materials science and engineering at Stanford.

The team collaborated with the California Department of Forestry and Fire Protection (CalFire) to test the new fire-retarding gel on two types of vegetation that frequently kindles fires — grass and chamise. The gel still provided complete fire protection even after half an inch (1.3 cm) of rainfall. The team notes that a typical commercial retardant formulation would provide little or no fire protection in the same scenario.

The material does degrade, but slowly, providing protection for months at a time. The researchers are now working with the California Department of Transportation and CalFire to test the material on high-risk roadside areas that are the origin of dozens of wildfires every year.

“We don’t have a tool that’s comparable to this,” said Alan Peters, a CalFire division chief in San Luis Obispo who monitored some of the test burns. “It has the potential to definitely reduce the number of fires.”

The paper “Wildfire prevention through prophylactic treatment of high-risk landscapes using viscoelastic retardant fluids” has been published in the journal PNAS.

Amazon is burning at a record rate in Brazil

The Amazon rainforest is burning at a record rate, with Brazil having declared a state of emergency over the rising number of fires in the region. So far this year, almost 73,000 fires have been detected, which marks an 83% increase from 2018 and the highest number on record since 2013.

Credit: NASA

Brazil saw a sharp spike in deforestation during July, which has been followed by extensive burning in August. Local newspapers have argued farmers in some regions are organizing “fire days” to take advantage of weaker enforcement by the Brazilian authorities.

While the Amazon rainforest is typically wet and humid, July and August — the onset of the dry season — are the area’s driest months, with “activity” peaking by early September and stopping by mid-November, according to NASA. The fires are largely linked to people clearing out the land for farming or ranching.

Satellite images show fires in the Brazilian states of Amazonas, Rondonia, Para, and Mato Grosso. The state of Amazonas is the most affected. The effects of damage to the Amazon go far beyond Brazil and its neighbors. The area’s rainforest generates more than 20% of the world’s oxygen and harbors 10% of the world’s known biodiversity.

The Amazon is usually referred to as “the lungs of the planet” and plays a major role in regulating the climate. The world would drastically change if the rainforest were to disappear, impacting everything from farming to the water we drink.

The smoke coming out from the forest fires can actually be seen from space. The European Union Earth Observation Program’s Sentinel satellites captured images of “significant amounts of smoke” over Amazonas, Rondonia and other areas. Skies also darkened over San Paulo after winds carried smoke.

Brazil’s president, Jair Bolsonaro, has also faced criticism. People are charging him with a lack of action and with encouraging logging and farming in the Amazon. Bolsonaro accused environmental groups of starting the fires, as a way to embarrass his administration.

“On the question of burning in the Amazon, which in my opinion may have been initiated by NGOs because they lost money, what is the intention? To bring problems to Brazil,” the president told a steel industry congress in Brasilia.

Social media started the hashtags #PrayforAmazonas and #AmazonRainforest. Twitter users criticized media for giving more attention to the fire at Notre Dame and other news than to the rainforest fires. Social media users also called out billionaires for lack of donations.

Forest Fire.

Wildfires lock away a ‘considerable amount of carbon’ for centuries, or even millennia

Wildfires could, surprisingly, act as net carbon traps.

Forest Fire.

Image via Pixabay.

The charcoal produced by wildfires can keep carbon out of the atmosphere for hundreds of years, new research from the Swansea University suggests.. The findings will help us better model changes in climate, especially as warmer mean temperatures in the arctic are leading to an unprecedented outbreak of wildfires and CO2 release in the area.

Burned and buried

Wildfires generate a large quantity of CO2. Generally, however, the gas is re-captured as vegetation grows back, so wildfires are considered to be more or less carbon-neutral once this regrowth process is complete.

“However, in a fire some of the vegetation is not consumed by burning, but instead transformed to charcoal,” explains Dr. Matthew Jones, lead author of the paper who recently joined the University of East Anglia’s (UEA) School of Environmental Sciences from Swansea University.

“This carbon-rich material can be stored in soils and oceans over very long time periods. We have combined field studies, satellite data, and modelling to better quantify the amount of carbon that is placed into storage by fires at the global scale.”

On average, wildfires burn an area roughly equivalent to the size of India every year and emit more carbon dioxide than global road, rail, shipping, and air transport combined, the team explains. Given the increased occurrence of wildfires in the past few years, a trend which will likely pick up in our warmer, drier future, the team set out to quantify how much carbon this charcoal can sequester from the air. All in all, the team says that this charcoal could lock away a considerable amount of carbon for years to come.

Vegetation growing back in burned areas draws on atmospheric CO2 to grow (through photosynthesis). This stage of the fire-recovery cycle takes just a bit under a year for grasslands, up to several decades in fire-adapted forests. In extreme cases, such as we’re seeing today in the arctic or tropical peatlands, full recovery may not occur for centuries. The timing of this recovery is important because the carbon that is emitted during the fire stays in the atmosphere and contributes to climate heating. Plants recapture it as they mature.

Overall, grassland fires don’t have that great of an impact; deforestation fires, however, are a particularly important contributor to climate change. Forests produce a lot of emissions as they burn, and take a long time to regrow, resulting in a long-term injection of carbon to the atmosphere.

The team explains that the charcoal resulting from forest fires — known as pyrogenic carbon — plays a larger part in mitigating these emissions than we’ve assumed. While they do emit CO2 to the atmosphere, landscape fires also transfer a significant fraction of the carbon locked in the affected vegetation to charcoal and other charred materials. The researchers say the quantity of this pyrogenic carbon is significant enough that it needs to be considered in global fire emission models.

As this material gets covered in soil, it locks carbon in place. Given time for flora to recover, the process actually leads to a net loss of carbon in the atmosphere — which is what we want.

“Our results show that, globally, the production of pyrogenic carbon is equivalent to 12 % of CO2 emissions from fires and can be considered a significant buffer for landscape fire emissions,” Dr. Jones said.

“Climate warming is expected to increase the prevalence of wildfires in many regions, particularly in forests. This may lead to an overall increase in atmospheric CO2 emissions from wildfires, but also an increase in pyrogenic carbon storage. If vegetation is allowed to recover naturally then the emitted CO2 will be recaptured by regrowth in future decades, leaving behind an additional stock of pyrogenic carbon in soils, lakes and oceans.”

The pyrogenic carbon will eventually find its way back into the atmosphere as the charcoal degrades, but it takes centuries or even millennia to do so. In the meantime, all the carbon it contains doesn’t influence the climate. It isn’t enough to offset man-made emissions, but every bit helps.

“This brings some good news, although rising CO2 emissions caused by human activity, including deforestation and some peatland fires, continue to pose a serious threat to global climate,” Dr. Jones adds.

The findings showcase the importance of factoring in pyrogenic carbon production in future climate models and in the global carbon cycle. The team plans to continue researching how the warmer more drought-prone climate of the future is going to impact the global extent of wildfires and to more accurately estimate the proportion of CO2 emissions recaptured by future vegetation regrowth.

The paper “Global fire emissions buffered by the production of pyrogenic carbon” has been published in the journal Nature Geoscience.

Credit: NASA.

Watch the ‘World on Fire’ in this amazing NASA satellite image

Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

Credit: NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

Some fires are so huge, they can be spotted from space. NASA’s satellites always keep an eye on important fires across the world, and the space agency recently released a stunning image to showcase this.

In this image that shows a “world on fire,” each red dot corresponds to a location on Earth where NASA’s thermal bands have detected actively burning fires. As you can see, most of them are concentrated in Africa — most likely these are agricultural fires, deliberately set up to clear the ground and replenish the soil with nutrients. But while these fires improve crops and grasses for livestock, they also produce fumes that choke the air.

North America is also pretty lit, but in this location, most fires are wildfires. The same applies to South America as well, where Chile, in particular, has experienced a large number of wildfires this year partly fueled by the mega-drought ravaging the country, but also due to the fact that native forests have been turned into flammable tree plantations. In Brazil, the fires are both agricultural and wildfires.

The red dots n Australia are bushfires, which are nothing out of the ordinary during dry seasons. The problem is that Australia is currently in the middle of winter (and a drought) — a sign that climate change is making area hotter and drier, extending bushfire season by as much as two months. In time, bushfires could engulf the whole continent.

The fire map of the world is available in an interactive format on NASA’s Earth Observing System Data and Information System (EOSDIS) Worldview application. This amazing interface enables users to add up to 700 global, full-res layers, resulting in virtually infinite possibilities of representing data. Many of the satellite imagery data is updated within three hours of observation. So, essentially, what you’re seeing is happening ‘right now’.

This particular image was released on August 22, 2018.

Bonus: aerosol maps

Credit: NASA.

Credit: NASA.

On a related note, the following two maps show aerosol movement outputted by the Goddard Earth Observing System Forward Processing (GEOS FP) on August 23, 2018. An aerosol is a suspension of fine solid particles or liquid droplets, in the air or in another gas. Examples of aerosols include fog, dust, forest exudates and geyser steam, as well as smoke and man-made air pollutants.

The maps show huge plumes of smoke drifting over North America and Africa, three different tropical cyclones churning in the Pacific Ocean, and large clouds of dust blowing over deserts in Africa and Asia. NASA’s Earth Observatory explains how to read them:

“The storms are visible within giant swirls of sea salt aerosol (blue), which winds loft into the air as part of sea sprayBlack carbon particles (red) are among the particles emitted by fires; vehicle and factory emissions are another common source. Particles the model classified as dust are shown in purple. The visualization includes a layer of night light data collected by the day-night band of the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP that shows the locations of towns and cities.”

“Some of the events that appear in the visualization were causing pretty serious problems on the ground. On August 23, Hawaiians braced for torrential rains and potentially serious floods and mudslides as Hurricane Lane approached. Meanwhile, twin tropical cyclones—Soulik and Cimaron—were on the verge of lashing South Korea and Japan. The smoke plume over central Africa is a seasonal occurrence and mainly the product of farmers lighting numerous small fires to maintain crop and grazing lands. Most of the smoke over North America came from large wildfires burning in Canada and the United States.”

Three Old Scientific Concepts Getting a Modern Look

If you have a good look at some of the underlying concepts of modern science, you might notice that some of our current notions are rooted in old scientific thinking, some of which originated in ancient times. Some of today’s scientists have even reconsidered or revamped old scientific concepts. We’ve explored some of them below.

4 Elements of the Ancient Greeks vs 4 Phases of Matter

The ancient Greek philosopher and scholar Empedocles (495-430 BC) came up with the cosmogenic belief that all matter was made up of four principal elements: earth, water, air, and fire. He further speculated that these various elements or substances were able to be separated or reconstituted. According to Empedocles, these actions were a result of two forces. These forces were love, which worked to combine, and hate, which brought about a breaking down of the elements.

What scientists refer to as elements today have few similarities with the elements examined by the Greeks thousands of years ago. However, Empedocles’ proposed quadruplet of substances bares resemblance to what we call the four phases of matter: solid, liquid, gas, and plasma. The phases are the different forms or properties material substances can take.

Water in two states: liquid (including the clouds), and solid (ice). Image via Wikipedia.

Compare Empedocles’ substances to the modern phases of matter. “Earth” would be solid. The dirt on the ground is in a solid phase of matter. Next comes water which is a liquid; water is the most common liquid on Earth. Air, something which surrounds us constantly in our atmosphere, is a gaseous form of matter.

And lastly, we come to fire. Fire has fascinated human beings for time beyond history. Fire is similar to plasma in that both generate electromagnetic radiation such as light. Most flames you see in your everyday life are not hot enough to be considered plasma. They are typically considered gaseous. A prime example of an area where plasma is formed is the sun. The ancient four elements have an intriguing correspondent in modern science.

Ancient Concept of Dome Sky vs. Simulation Hypothesis

Millennia ago, people held the notion that his world was flat. Picture a horizontal cooking sheet with a transparent glass bowl set on top of it. Primitive people thought of the Earth in much the same way. They considered the land itself as flat and the sky as a dome. However, early Greek philosophers such as Pythagoras (c. 570-495 BC) — who is also known for formulating the Pythagorean theorem — understood that Earth was actually spherical.

Fast forward to the 21st century. Now scientists are considering the scientific concept of the dome once again but in a much more complex manner.

Regardless of what conspiracy lovers would have you believe, the human race has ventured into outer space, leaving the face of the Earth to travel to the stars. In the face of all our achievements, some scientists actually question if reality is real, a mindboggling and apparently laughable idea.

But some scientists have wondered if we could be existing in a computer simulation. The gap between science and science fiction starts to become very fine when considering this.

This idea calls to mind classic sci-fi plots such as those frequently played out in The Twilight Zone in which everything the characters take as real turns out to be something entirely unexpected. You might also remember the sequence in Men in Black in which the audience sees that the entire universe is inside an alien marble. Bill Nye even uses the dome as an example in discussing hypothetical virtual reality. This gives one the feeling that he is living in a snowglobe.

Medieval Alchemy vs. Modern Chemistry

The alchemists of the Middle Ages attempted to prove that matter could be transformed from one object into an entirely new object. One of their fondest goals they wished to achieve was the creation of gold from a less valuable substance. They were dreaming big, but such dreams have not yet come to fruition. Could it actually be possible to alter one type of matter into another?

Well, modern chemists may be well on their way to achieving this feat some day. They are pursuing the idea of converting light into matter, as is expressed in Albert Einstein’s famous equation. Since 2014, scientists have been claiming that such an operation would be quite feasible, especially with extant technology.

Einstein’s famous equation.

Light is made up of photons, and a contraption capable of performing the conversion has been dubbed “photon-photon collider.” Though we might not be able to transform matter into other matter in the near future, it looks like the light-to-matter transformation has a bright outlook.

Firehawks: In Australia, birds of prey are intentionally setting the forests on fire

Fire is supposed to be uniquely human, but that’s no longer the case. Researchers have confirmed ancient aboriginal legends: certain birds of prey in Australia spread wildfire in order to scare off, and ultimately hunt their prey in a feeding frenzy.

Image credits: Dick Eussen.

Dick Eussen thought he’d finally managed to put down the fire. He had it cornered, behind the side of a highway deep in the Australian outback. Eussen, a veteran firefighter in Australia’s Northern Territory, was convinced the fire couldn’t jump to the other side. He’d seen similar things in the past, and they never jumped. But this time, it did.

Eussen rushed to the other side to quench the flames, still surprised by how unexpectedly the fire jumped. Looking for answers, he looked up. Like a dark spirit, a whistling kite flew in the sky, a burning twig in its talons. After about 20 meters, it dropped the twig and the flames started again.

In total, there were seven flare-ups that day. By the end of it all, Eussen was exhausted and puzzled.

At least three species have been observed to carry out this behavior — one of them, the brown falcon (Falco berigora), is pictured here. Image credits: Benjamint444 / Wikipedia.

Australia is no stranger to extreme heat, and it’s no stranger to fire. Year after year, bushfires devastate vast swaths of land, destroying ecosystems and posing a huge threat to any nearby creatures, be they animal or human. But for some, bushfires can be a godsend. A new study reports that at least three bird species — the Black Kite (Milvus migrans), Whistling Kite (Haliastur sphenurus), and Brown Falcon (Falco berigora) — not only use, but also intentionally spread wildfires for their own purposes. The birds were spotted carrying burning twigs, as well as placing new ones into the flames, only to pick them up again and spread the fire.

“Observers report both solo and cooperative attempts, often successful, to spread wildfires intentionally via single-occasion or repeated transport of burning sticks in talons or beaks. This behavior, often represented in sacred ceremonies, is widely known to local people in the Northern Territory, where we carried out ethno-ornithological research from 2011 to 2017.”

For the raptors, this creates a feeding frenzy, an all-you-can-eat buffet. Groups of desperate creatures flee the burning areas, leaving the safety of the tree cover and running into the open, where they’re easy prey.

Co-author Bob Gosford, an Australian indigenous-rights lawyer turned biologist, says the birds have a lot to win from this behavior.

“Black kites and brown falcons come to these fronts because it is just literally a killing frenzy,” he said in a 2016 interview with the Australian Broadcasting Corporation. “It’s a feeding frenzy, because out of these grasslands come small birds, lizards, insects, everything fleeing the front of the fire.”

But while this finding is thrilling for biologists, it isn’t actually representing newly observed behavior. This behavior has been described before.

“I have seen a hawk pick up a smouldering stick in its claws and drop it in a fresh patch of dry grass half a mile away, then wait with its mates for the mad exodus of scorched and frightened rodents and reptiles,” wrote Waipuldanya Phillip Roberts in I, the Aboriginal, a 1964 autobiography of Roberts compiled by Australian journalist Douglas Lockwood.

“When that area was burnt out, the process was repeated elsewhere.”

Aboriginal peoples have observed this behavior for millennia, and even feature it in ritualistic ceremonies. The indigenous people of the Northern Territory have long claimed that a group of birds they call “firehawks” can control fire by spreading burning sticks.

“We’re not discovering anything,” cautions co-author Mark Bonta, a National Geographic grantee and geographer at Penn State University. “Most of the data that we’ve worked with is collaborative with Aboriginal peoples… They’ve known this for probably 40,000 years or more.” 

However, such tales are often unreliable and having a proper scientific description paves the way for a proper understanding of the behavior. Also, there was a theory that in the frenzy, the birds of prey mistakenly grab twigs, and when they realize their mistake, they drop them. This study demonstrates a clear intention to spread the wildfire.

Gosford and his colleagues encourage people to send them photos or videos of this behavior to better understand the process, but they haven’t had much success so far.

Understanding these arsonist birds is important not only from a biological perspective, but also considering fire safety. Aside from humans and lightning, there’s a new culprit which spreads wildfires — one with wings instead of hands. Hopefully, new research will establish how much of an impact these birds have.

Journal Reference: Mark Bonta, Robert Gosford, Dick Eussen, Nathan Ferguson, Erana Loveless, and Maxwell Witwer. Intentional Fire-Spreading by “Firehawk” Raptors in Northern Australia. https://doi.org/10.2993/0278-0771-37.4.700

Building fire.

Salem Fire Department veteran explains basic fire behavior with a burning dollhouse

Tragedy befell London last night, as the 24-story Grenfell Tower near Ladbroke Grove caught fire and burned well into the morning hours. Five local hospitals took in over 50 people suffering from burns, several of which are still in critical conditions, and 6 fatalities have been confirmed so far.

In the blaze’s wake, concerns were raised about the adequacy of fire safety measures such as insulated doors and warning systems throughout London and the UK. But the UK has some of the best fire planning and safety products anywhere in the world, going as far as stipulating what types of construction materials can be used to reduce fire risk. That’s why experts, such as Christopher Miers, an architect and the founder of construction dispute resolution group Probyn Miers, were completely shocked with how fast the fire had spread.

“Nowadays, in the UK, we don’t use materials with this degree of combustibility,” he said for The Guardian.

“They are sandwich panels which are two sheets of aluminium with a core, and the core can be made of different materials. In other parts of the world, in the Middle East and in China, the core material was still being made of combustible plastic product, but that is no longer permitted and has not been permitted in the UK for a long time. The panels are not likely to have a combustible element to them. It’s much more likely that the firespread is not the panels themselves, but it’s more likely to have spread by other means.”

**UPDATE: It seems that residents of the Grenfell Tower in London, which burned down, filed several complaints regarding fire hazards — the complaints were ignored by the owners, and no action was taken. Furthermore, the landlord covered the fire alarms with plastic masks, which caused them to catch fire instantly. Not a single fire alarm rang during the enormous fire, which killed at least 6 people yesterday.**

But what are those “other means,” and how does fire usually behave when confined to a building? Well, Alan Fitzpatrick, an 11-year veteran of the Salem Fire Department in Oregon has a good grasp of both those issues. To help teach fire behavior basics to recruits, Fitzpatrick uses giant burning dollhouses he builds in his spare time — and he luckily uploaded one of his demonstrations to help us better understand the hidden dangers of home fires as well.

I’m going to let him do the brunt of the explaining since he’s obviously more qualified but it’s remarkable just how much difference strong ventilation makes for a blaze.

While Fitzpatrick approaches the issue mostly from a firefighter’s angle, knowing the basics of how a fire starts and grows might just make the difference between life and death in a blaze.

Video credits Salem Fire Department.

 

Study found human habitation promoted forest growth in British Columbia over the past 13,000 years

We’ve often covered the effect human life is having on the environment pretty extensively on ZME Science (see here, here, and here for a few highlights) and for the most part, it’s been pretty grim.

These trees may not be here if the First Nations hadn’t lived in British Columbia for as long as they did.
Image credits Will McInnes / Hakai Institute.

So what gives? Are we doomed to destroy the world (or worlds) around us over and over again in our thirst for resources, or is there any reverse to the coin? University of Waterloo Faculty of Environment Professor Andrew Trant says there is. He led a study in partnership with the University of Victoria and the Hakai Institute which found that the almost 13,000 thousand years of repeated human habitation in British Columbia by the First Nations has actually enhanced temperate rain forest productivity.

The research put together remote-sensed, ecological and archaeological data from coastal sites that have been settled by the First Nations for thousands of years. The trees growing at these sites were found to be taller, wider, and overall in better health than those in the surrounding forest.

And it can all be traced to shell middens and fire.

“It’s incredible that in a time when so much research is showing us the negative legacies people leave behind, here is the opposite story,” said Trant, a professor in Waterloo’s School of Environment, Resources and Sustainability.

“These forests are thriving from the relationship with coastal First Nations. For more than 13,000 years —500 generations—people have been transforming this landscape. So this area that at first glance seems pristine and wild is actually highly modified and enhanced as a result of human behaviour.

Intertidal shellfish gathering has really picked up in the area over the last 6,000 years, leading to an accumulation of deep shell middens in the area. The discarded middens covered thousands of square meters of forest ground, in some cases being deposited in piles more than five meters deep. In what’s probably the most fortunate turnout of littering that I know of, depositing the remains inland brought significant quantities of marine-derived nutrients to the soil. As the shells slowly deteriorated, they leached calcium into the soil, promoting tree growth.

Image credits Will McInnes / Hakai Institute.

The team also found evidence that the use of fire also helped make the forests we see today. Along with the disposal of shells, ash introduced important nutrients to the forest’s soil, increased its pH levels, and improved soil drainage.

The study examined 15 former habitation sites in the Hakai Lúxvbálís Conservancy on Calvert and Hecate Islands using remote-sensed, ecological and archaeological methods to compare forest productivity with a focus on western red cedar. It is the first work to find evidence of long-term use of intertidal resources increasing a forest system’s productivity.

Trant believes that similar findings will occur at archaeological sites along many global coastlines.

“These results alter the way we think about time and environmental impact,” he said. “Future research will involve studying more of these human-modified landscapes to understand the extent of these unexpected changes.”

The full paper, titled “Intertidal resource use over millennia enhances forest productivity” has been published in the journal Nature Communications.

 

Become a fire-bender – all you need is some electricity

Take a candle, light it, turn it on its side — we all know what will happen. The convection cell that forms around the flame keeps licking up towards the sky (or ceiling) regardless of the orientation of the fuel.

But can the movement of air be overcome, can we make a fire burn horizontally? Well, the short answer is yes, yes we can — we just have to use science.

The long answer

The chemical reaction that fire relies on is oxidation. While burning, part of the chemical building blocks of the piece of fuel are tied to atoms of O, releasing the energy they store in the initial chemical bonds as heat and light. The main by-products are carbon dioxide and water, most often in a gaseous form, mixed with other elements depending on the fuel used — this is what creates smoke.

Now, the more physics-savvy of you already spotted two words in that previous paragraph, “gas” and “heat.” When you heat a gas, or subject it to a strong enough electromagnetic field, you get plasma, one of the four fundamental states of matter we know of today.

The main difference between plasma and a gas is that in the former, a large fraction of the atoms are ionized — because they environment is so hot, they slam into each other hard enough to allow some electrons to temporarily escape their host atom. Plasma is loosely described as an electrically neutral medium of unbound positive and negative particles (meaning that overall, it has zero electrical charge, but zoom in and it’s more of a soup of +’s and -‘s.)

Plasma thus gains some electrical properties that a non-ionized gas doesn’t have; it becomes conductive and it responds to electrical and magnetic fields. And that property is exactly what they guys from the Rino Foundation used to make their flame bend as it does in this video:

https://www.youtube.com/watch?v=yuCGZyS3njE

Fire is a genuine plasma, not the most ionized or homogeneous, but it is the kind we’re most used to. Even small and relatively cool fires, like candle flames, respond to electric fields and are pretty conductive.

So, the next time you go to a party and really need to impress your crush with awesome fire-bending skills (and for some reason happen to carry a few sheets of copper and electrical wiring around, we don’t judge), you’ll know exactly how to go about doing that. You’re welcome.

Two students created a device that extinguishes fires with soundwaves

What do fires and deep sounds have in common? Not much right now, but they might have a lot in the future.Two George Mason University students have designed a device that uses sound waves to put out fires, thus potentially eliminating the need for carrying around huge quantities of water and costly cleaning operations. Here’s how it works:

Seth Robertson and Viet Tran’s wave extinguisher is not something you see everyday (or any day, for that matter) – they managed to hit the right note to blow fires away using only amps, a speaker and a device they invented and call “collimater”. The key here is to find a frequency which blows the oxygen away, and sound in the 30 to 60 hertz range seems to do the trick. Why does this work?

Well, sound waves are pressure waves, and they can displace some of the oxygen as they travel through the air. At some frequencies, the oxygen is pushed out more effectively, basically separated from the fire. The pressure waves then goes back and forth, agitating the oxygen away from the fire, preventing it from reigniting.

Robertson and Tran are electrical and computer engineering majors, and they came up with this idea for their project because they disliked all the ideas that came from their professors. Naturally, there were many naysayers. Most professors refused to serve as their advisors. Both colleagues and professors seemed extremely skeptical and advised them to pick something else, but they persevered, and ultimately Brian Mark agreed to oversee it. But even he was not convinced at first…

“My initial impression was that it wouldn’t work,” Mark, their adviser, said. “Some students take the safe path, but Viet and Seth took the higher-risk option.”

George Mason University.

 

Their first design didn’t work at all – they used very high frequencies of 30,000 hertz, but even though the flames danced, they never went out. But as they moved to lower frequencies, everything smoothened out.

“I honestly didn’t think it would work as well as it did,” Tran said.

Of course, they started out small and for now, their device can only put out small fires, but there is no reason why they shouldn’t scale it. For now, they want to test it more and see if the required frequency differs for some materials – but for starters, the advantages are obvious. Sure, you need some source of energy to use it, but that’s much easier to carry than huge quantities of water or powder – and then you don’t have any cleaning to do. To make things even better, this could actually work in space – where putting out a fire is actually really hard.

“In space, extinguisher contents spread all over. But you can direct sound waves without gravity,” explains Robertson.

fire-zerogravity

How fire burns in zero gravity

In space, of course, you can’t have any fires because there isn’t any oxidizer (i.e. oxygen) to sustain the combustion process. Inside a spacecraft or in the International Space Station, however, things are a bit different: you have the same air mixture as on Earth, but because gravity is millions of times weaker, an open flame behaves significantly different.

Lighting a candle in space

fire-zerogravity

Left: a candle flame in normal gravity; right: a candle flame in microgravity. Image: Science.

 

First, let’s see how combustion works here on Earth. Imagine a big bonfire, beautifully blazing away in the mountainside, with you and your best friends roasting some marshmallows. For a moment, you ponder the fire itself. How does it all work? As carbon and oxygen molecules revolve around your head, you begin to understand. As the fuel (wood) burns, it heats the air around it making it less dense. Because gravity pulls down anything with a higher density, the hot air travels upwards and leaves the vicinity of the fire, which is very convenient. With the hot air gone, fresh air is drawn into the gap providing a new source of oxygen-rich air.

This is called buoyancy and is what makes the flame shoot up and flicker. Thus, the cycle continues until all the fuel is used up. In microgravity, however, things are a lot different.

fire in microgravity

fire in microgravity

In microgravity, there’s no updraft and oxygen is drawn into the flame through a completely different mechanism. The first such experiment was performed in 1997 aboard the Columbia shuttle. Called Structure of Flame Balls at Low Lewis-number (SOFBALL), the experiment consisted of a sealed chamber where flames flying onboard the space shuttle can burn for a long time.

 

 A schematic diagram of a flame ball. Credit: Paul Ronney.

A schematic diagram of a flame ball. Credit: Paul Ronney.

The first thing scientists noticed was the shape of the flame. While on Earth a fire’s flame is elongated, in microgravity it is spherical – like a fireball. That’s because the spherical flame is fed by the slower process of diffusion, so the flame occurs at a border between fuel and air; effectively the entire surface of the flame is the “bottom”, reacting with fresh air close enough to the fuel source to combust, in a rough sphere. Because exhaust gases like CO2 can’t leave the combustion area, by the same dictum, the outward diffusion of combustion gases can limit the inward diffusion of oxygen to an extent that the zero gravity flame will die a short time after ignition.

You might have also noticed from the pictures in this article that fire has a different color in microgravity. When a candle burns, it’s being consumed molecule by molecule. Sometimes, the fuel — long strings of carbon — gets pushed upwards where it burns like charcoal, glowing yellow. Without gravity, the carbon strings don’t get burned, and the flame is blue, cooler, and much much dimmer.

Studying fire in microgravity can render some important practical insight. For decades engineers have been trying to build internal combustion engines that run on a lean mixture of fuel and oxygen, which should produce something like a flame ball in space.  If you could burn a leaner fuel mixture in engines, you could get higher fuel efficiency and lower pollutant formation, says Paul Ronney, a combustion researcher at the University of Southern California who conceived and helped design the shuttle flame experiments. Because the chemical reaction rates involved in combustion are very sensitive to temperature, if you increase the temperature by 10 percent, the rate more than doubles — and the rate at which some pollutants form increases thirteenfold, particularly the oxides of nitrogen that make our skies brown.

Then, of course, there’s the issue of safety. Because fire behaves considerably different in microgravity than in Earth’s gravity, studying fireballs is very important to designing safety measures and systems. For instance, if a candle is burning on Earth you might think about stomping it to put down the flame. If you were to do that in a spacecraft, you might accelerate combustion, at least temporarily, because you are creating an airflow that did not exist before. Flames in low-gravity tend to spread slowly, so stomping might cause a flame to jump to something else when it wouldn’t have otherwise. Furthermore, flame balls are stealthy: they give off no smoke and little or no visible light. It’s very hard to extinguish something you can’t find.

Two images of a live human subject as seen through flames. When viewed in infrared or white light, the man is almost completely occluded (left). The new system reproduces the image behind the flames using holography, revealing a man wearing a t-shirt and glasses (right). Credit: Optics Express.

Infrared holographic imaging allows firefighters to see through flames

Two images of a live human subject as seen through flames. When viewed in infrared or white light, the man is almost completely occluded (left). The new system reproduces the image behind the flames using holography, revealing a man wearing a t-shirt and glasses (right). Credit: Optics Express.

Two images of a live human subject as seen through flames. When viewed in infrared or white light, the man is almost completely occluded (left). The new system reproduces the image behind the flames using holography, revealing a man wearing a t-shirt and glasses (right). Credit: Optics Express.

I have nothing but the deepest admiration and respect for fighters – always faithful in the face of peril and always ready to put their necks on the line in order to save people from the hellish depths. As one can imagine, firefighting tech has evolved a great deal from simple fireproof clothing and a bare axe, still there is still much that can be done. One of the great challenges firefighters face is seeing through thick smoke and flames in order to reach people in need, and a recent breakthrough by a group of Italian scientists that devised an infrared digital holographic imaging system might change all that forever.

Currently, some firefighting departments employ infrared cameras and imaging systems in order to see through smoke. However, the system becomes useless if flames are in the vicinity, as the intense radiation obstructs  the sensitive detectors and limit their use in the field.

“IR cameras cannot ‘see’ objects or humans behind flames because of the need for a zoom lens that concentrates the rays on the sensor to form the image,” says Pietro Ferraro of the Consiglio Nazionale delle Ricerche (CNR) Istituto Nazionale di Ottica in Italy. By eliminating the need for the zoom lens, the new technique avoids this drawback.

To tackle this issue, the Italian researchers devised an infrared camera and detector that builds a holographic image – a 3-D image of an object. To create a hologram, like the one you have on your credit card, a laser beam is split into two  – an object beam and a reference beam. The object beam is shone onto the object being imaged, and it is combined with the reference beam, the interference pattern produces a 3-D image.

The difference between life and death

The holographic imaging system developed in Italy employs a beam of infrared light which is widely dispersed throughout a room. Unlike visible light, infrared isn’t blocked by smoke, but it does bounce off objects or people. The bounced off IR is then collected by a holographic imager. The information is then decoded by a computer to reveal the objects or people behind smoke or flames – all in a live 3-d scene.

In the video below you can see just how well the system works in this comparative study – on the left, imaging with simple infrared, on the right holographic imaging.

The next step researchers plan on making is to scale the system so that it may fit in firefighting gear. Also, the system could be installed as a fixed installation in buildings, tunnels and such, so that firefighters, even without the gear on hand, can be directed to the right spot. Other applications, like medical, are also viable options.

“Besides life-saving applications in fire and rescue, the potential to record dynamic scenes of a human body could have a variety of other biomedical uses including studying or monitoring breathing, cardiac beat detection and analysis, or measurement of body deformation due to various stresses during exercise,” Ferraro says. “We are excited to further develop this technology and realize its application for saving and improving human life.”

Findings were reported in a paper published in the journal Optics Express.

Color image of a fuel droplet burning in space during NASA's Flame Extinguishment Experiment aboard the International Space Station. (c) NASA

Firefighting in space might lead to important combustion advancements

Space offers incredibly fascinating experimental conditions for various scientific studies, otherwise very hard or practically impossible to replicate on Earth. Microgravity is something of great interest to scientists, and even simple experiments with fire are extremely insightful.

Color image of a fuel droplet burning in space during NASA's Flame Extinguishment Experiment aboard the International Space Station. (c) NASA

Color image of a fuel droplet burning in space during NASA's Flame Extinguishment Experiment aboard the International Space Station. (c) NASA

Combustion in space occurs at much lower temperatures and with a lower amount of required oxygen, and to better understand the process, scientists established the Flame Extinguishment Experiment, known as FLEX. The experiment was set-up on the International Space Station‘s Destiny module, however it was all remotely controlled from 200 miles away at NASA’s John Glenn Research Center in Cleveland, Ohio.

What scientists observed was that curiously enough the flame of an ignited droplet of fuel is completely spherical, something incredibly difficult to achieve on Earth. This spherical symmetry makes observing the droplet’s behavior and describing it mathematically much easier.

The Destiny module is filled with cameras and sensors which fed the John Glenn Research Center with every discrete piece of information they needed. In the chamber, small drops of chemicals such as heptane or methanol were ignited and allowed to burn for 20 seconds. This was repeated many hundreds of times under various atmospheric conditions by a device called Multiuser Droplet Combustion Apparatus .

“Research leads to a better understanding of fire behavior,” said study’s leader, University of California, San Diego, aerospace engineering professor Forman Williams,. “And better understanding ultimately leads to better safety designs.”

Besides developing better fire hazard safety designs for both on Earth and in space, scientists hope to somehow recreate the conditions found in the experiment inside a combustion engine. If they can manage to compensate microgravity somehow, this could be the greatest breakthrough in the field since the introduction of stratified injection.

“Findings could lead to new designs for cleaner fuels that have a smaller carbon footprint and emit fewer pollutants, among other applications,” according to a University of California, San Diego, statement.

Williams and colleagues will present their FLEX findings in an upcoming conference in Poland.

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