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92-759: The name of the Brandenkopf ("Fire Peak") is derived from a great forest fire in 1730. Before this event it was called the Varnlehenskopf . The Brandenkopf is well developed with roads and footpaths (including the Hansjakobweg II and a link to the West Way , 3.5 km away) from several directions. There is a transmitter, the Sender Brandenkopf , on the mountain. The 32-metre-high Brandenkopf Tower ( Brandenkopfturm ) has stood on

184-570: A defensible space be maintained by clearing flammable materials within a prescribed distance from the structure. Communities in the Philippines also maintain fire lines 5 to 10 meters (16 to 33 ft) wide between the forest and their village, and patrol these lines during summer months or seasons of dry weather. Continued residential development in fire-prone areas and rebuilding structures destroyed by fires has been met with criticism. The ecological benefits of fire are often overridden by

276-469: A 15 mile radius. Additionally, Sensaio Tech , based in Brazil and Toronto, has released a sensor device that continuously monitors 14 different variables common in forests, ranging from soil temperature to salinity. This information is connected live back to clients through dashboard visualizations, while mobile notifications are provided regarding dangerous levels. Satellite and aerial monitoring through

368-470: A 24-hour fire day that begins at 10:00 a.m. due to the predictable increase in intensity resulting from the daytime warmth. Climate change promotes the type of weather that makes wildfires more likely. In some areas, an increase of wildfires has been attributed directly to climate change. Evidence from Earth's past also shows more fire in warmer periods. Climate change increases evapotranspiration . This can cause vegetation and soils to dry out. When

460-663: A benefit for people. Modern forest management often engages in prescribed burns to mitigate fire risk and promote natural forest cycles. However, controlled burns can turn into wildfires by mistake. Wildfires can be classified by cause of ignition, physical properties, combustible material present, and the effect of weather on the fire. Wildfire severity results from a combination of factors such as available fuels, physical setting, and weather. Climatic cycles with wet periods that create substantial fuels, followed by drought and heat, often precede severe wildfires. These cycles have been intensified by climate change . Wildfires are

552-485: A common type of disaster in some regions, including Siberia (Russia), California (United States), British Columbia (Canada), and Australia . Areas with Mediterranean climates or in the taiga biome are particularly susceptible. Wildfires can severely impact humans and their settlements. Effects include for example the direct health impacts of smoke and fire, as well as destruction of property (especially in wildland–urban interfaces ), and economic losses. There

644-610: A fire starts in an area with very dry vegetation, it can spread rapidly. Higher temperatures can also lengthen the fire season. This is the time of year in which severe wildfires are most likely, particularly in regions where snow is disappearing. Weather conditions are raising the risks of wildfires. But the total area burnt by wildfires has decreased. This is mostly because savanna has been converted to cropland , so there are fewer trees to burn. Climate variability including heat waves , droughts , and El Niño , and regional weather patterns, such as high-pressure ridges, can increase

736-478: A height of 10 metres is exploited by a wind turbine . In summer 2002 a second wind turbine, the Bürgerwindrad Brandenkopf , was opened about 350 metres west of the hiking home. This turbine, an Enercon E-58, which has a hub height of 70 metres (100 metres total height) generating a nominal 1000 kW, produces an average of 2,000,000 kWh of electrical power per year. and is thus one of

828-546: A new fire detection tool is in operation at the U.S. Department of Agriculture (USDA) Forest Service (USFS) which uses data from the Suomi National Polar-orbiting Partnership (NPP) satellite to detect smaller fires in more detail than previous space-based products. The high-resolution data is used with a computer model to predict how a fire will change direction based on weather and land conditions. In 2014, an international campaign

920-415: A number expected to rise to 30,000 by 2050. The economic impact is also significant, with projected costs reaching $ 240 billion annually by 2050, surpassing other climate-related damages. Over the past century, wildfires have accounted for 20–25% of global carbon emissions, the remainder from human activities. Global carbon emissions from wildfires through August 2020 equaled the average annual emissions of

1012-593: A planet's atmosphere insulate the planet from losing heat to space, raising its surface temperature. Surface heating can happen from an internal heat source as in the case of Jupiter , or from its host star as in the case of the Earth . In the case of Earth, the Sun emits shortwave radiation ( sunlight ) that passes through greenhouse gases to heat the Earth's surface. In response, the Earth's surface emits longwave radiation that

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1104-545: A policy of allowing some wildfires to burn is the cheapest method and an ecologically appropriate policy for many forests, they tend not to take into account the economic value of resources that are consumed by the fire, especially merchantable timber. Some studies conclude that while fuels may also be removed by logging, such thinning treatments may not be effective at reducing fire severity under extreme weather conditions. Building codes in fire-prone areas typically require that structures be built of flame-resistant materials and

1196-503: A possible resolution to human operator error. These systems may be semi- or fully automated and employ systems based on the risk area and degree of human presence, as suggested by GIS data analyses. An integrated approach of multiple systems can be used to merge satellite data, aerial imagery, and personnel position via Global Positioning System (GPS) into a collective whole for near-realtime use by wireless Incident Command Centers . A small, high risk area that features thick vegetation,

1288-531: A rapid forward rate of spread (FROS) when burning through dense uninterrupted fuels. They can move as fast as 10.8 kilometres per hour (6.7 mph) in forests and 22 kilometres per hour (14 mph) in grasslands. Wildfires can advance tangential to the main front to form a flanking front, or burn in the opposite direction of the main front by backing . They may also spread by jumping or spotting as winds and vertical convection columns carry firebrands (hot wood embers) and other burning materials through

1380-410: A rate that is directly proportional to the fourth power of its temperature . Some of the radiation emitted by the Earth's surface is absorbed by greenhouse gases and clouds. Without this absorption, Earth's surface would have an average temperature of −18 °C (−0.4 °F). However, because some of the radiation is absorbed, Earth's average surface temperature is around 15 °C (59 °F). Thus,

1472-695: A remote site and sent via overnight mail to the fire manager . During the Yellowstone fires of 1988 , a data station was established in West Yellowstone , permitting the delivery of satellite-based fire information in approximately four hours. Public hotlines, fire lookouts in towers, and ground and aerial patrols can be used as a means of early detection of forest fires. However, accurate human observation may be limited by operator fatigue , time of day, time of year, and geographic location. Electronic systems have gained popularity in recent years as

1564-434: A state of radiative equilibrium , in which the power of outgoing radiation equals the power of absorbed incoming radiation. Earth's energy imbalance is the amount by which the power of incoming sunlight absorbed by Earth's surface or atmosphere exceeds the power of outgoing longwave radiation emitted to space. Energy imbalance is the fundamental measurement that drives surface temperature. A UN presentation says "The EEI

1656-569: A strong human presence, or is close to a critical urban area can be monitored using a local sensor network . Detection systems may include wireless sensor networks that act as automated weather systems: detecting temperature, humidity, and smoke. These may be battery-powered, solar-powered, or tree-rechargeable : able to recharge their battery systems using the small electrical currents in plant material. Larger, medium-risk areas can be monitored by scanning towers that incorporate fixed cameras and sensors to detect smoke or additional factors such as

1748-448: A surface temperature of 5,500 °C (9,900 °F), so it emits most of its energy as shortwave radiation in near-infrared and visible wavelengths (as sunlight). In contrast, Earth's surface has a much lower temperature, so it emits longwave radiation at mid- and far- infrared wavelengths. A gas is a greenhouse gas if it absorbs longwave radiation . Earth's atmosphere absorbs only 23% of incoming shortwave radiation, but absorbs 90% of

1840-779: A susceptible area: an ignition source is brought into contact with a combustible material such as vegetation that is subjected to enough heat and has an adequate supply of oxygen from the ambient air. A high moisture content usually prevents ignition and slows propagation, because higher temperatures are needed to evaporate any water in the material and heat the material to its fire point . Dense forests usually provide more shade, resulting in lower ambient temperatures and greater humidity , and are therefore less susceptible to wildfires. Less dense material such as grasses and leaves are easier to ignite because they contain less water than denser material such as branches and trunks. Plants continuously lose water by evapotranspiration , but water loss

1932-448: Is also the potential for contamination of water and soil. At a global level, human practices have made the impacts of wildfire worse, with a doubling in land area burned by wildfires compared to natural levels. Humans have impacted wildfire through climate change (e.g. more intense heat waves and droughts ), land-use change , and wildfire suppression . The carbon released from wildfires can add to carbon dioxide concentrations in

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2024-478: Is an associated effective emission temperature (or brightness temperature ). A given wavelength of radiation may also be said to have an effective emission altitude , which is a weighted average of the altitudes within the radiating layer. The effective emission temperature and altitude vary by wavelength (or frequency). This phenomenon may be seen by examining plots of radiation emitted to space. Earth's surface radiates longwave radiation with wavelengths in

2116-440: Is because their molecules are symmetrical and so do not have a dipole moment.) Such gases make up more than 99% of the dry atmosphere. Greenhouse gases absorb and emit longwave radiation within specific ranges of wavelengths (organized as spectral lines or bands ). When greenhouse gases absorb radiation, they distribute the acquired energy to the surrounding air as thermal energy (i.e., kinetic energy of gas molecules). Energy

2208-465: Is because when these molecules vibrate , those vibrations modify the molecular dipole moment , or asymmetry in the distribution of electrical charge. See Infrared spectroscopy .) Gases with only one atom (such as argon, Ar) or with two identical atoms (such as nitrogen, N 2 , and oxygen, O 2 ) are not infrared active. They are transparent to longwave radiation, and, for practical purposes, do not absorb or emit longwave radiation. (This

2300-454: Is being measured. Strengthening of the greenhouse effect through additional greenhouse gases from human activities is known as the enhanced greenhouse effect . As well as being inferred from measurements by ARGO , CERES and other instruments throughout the 21st century, this increase in radiative forcing from human activity has been observed directly, and is attributable mainly to increased atmospheric carbon dioxide levels. CO 2

2392-435: Is essential to the greenhouse effect. If the lapse rate was zero (so that the atmospheric temperature did not vary with altitude and was the same as the surface temperature) then there would be no greenhouse effect (i.e., its value would be zero). Greenhouse gases make the atmosphere near Earth's surface mostly opaque to longwave radiation. The atmosphere only becomes transparent to longwave radiation at higher altitudes, where

2484-422: Is expressed in units of W/m , which is the number of joules of energy that pass through a square meter each second. Most fluxes quoted in high-level discussions of climate are global values, which means they are the total flow of energy over the entire globe, divided by the surface area of the Earth, 5.1 × 10  m (5.1 × 10  km ; 2.0 × 10  sq mi). The fluxes of radiation arriving at and leaving

2576-517: Is mostly absorbed by greenhouse gases. The absorption of longwave radiation prevents it from reaching space, reducing the rate at which the Earth can cool off. Without the greenhouse effect, the Earth's average surface temperature would be as cold as −18 °C (−0.4 °F). This is of course much less than the 20th century average of about 14 °C (57 °F). In addition to naturally present greenhouse gases, burning of fossil fuels has increased amounts of carbon dioxide and methane in

2668-728: Is no longer an expectation, but the majority of wildfires are often extinguished before they grow out of control. While more than 99% of the 10,000 new wildfires each year are contained, escaped wildfires under extreme weather conditions are difficult to suppress without a change in the weather. Wildfires in Canada and the US burn an average of 54,500 square kilometers (13,000,000 acres) per year. Above all, fighting wildfires can become deadly. A wildfire's burning front may also change direction unexpectedly and jump across fire breaks. Intense heat and smoke can lead to disorientation and loss of appreciation of

2760-491: Is produced by fossil fuel burning and other activities such as cement production and tropical deforestation . Measurements of CO 2 from the Mauna Loa Observatory show that concentrations have increased from about 313 parts per million (ppm) in 1960, passing the 400 ppm milestone in 2013. The current observed amount of CO 2 exceeds the geological record maxima (≈300 ppm) from ice core data. Over

2852-473: Is prone to offset errors, anywhere from 2 to 3 kilometers (1 to 2 mi) for MODIS and AVHRR data and up to 12 kilometers (7.5 mi) for GOES data. Satellites in geostationary orbits may become disabled, and satellites in polar orbits are often limited by their short window of observation time. Cloud cover and image resolution may also limit the effectiveness of satellite imagery. Global Forest Watch provides detailed daily updates on fire alerts. In 2015

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2944-445: Is sometimes called thermal radiation . Outgoing longwave radiation (OLR) is the radiation from Earth and its atmosphere that passes through the atmosphere and into space. The greenhouse effect can be directly seen in graphs of Earth's outgoing longwave radiation as a function of frequency (or wavelength). The area between the curve for longwave radiation emitted by Earth's surface and the curve for outgoing longwave radiation indicates

3036-424: Is the most critical number defining the prospects for continued global warming and climate change." One study argues, "The absolute value of EEI represents the most fundamental metric defining the status of global climate change." Earth's energy imbalance (EEI) was about 0.7 W/m as of around 2015, indicating that Earth as a whole is accumulating thermal energy and is in a process of becoming warmer. Over 90% of

3128-404: Is transferred from greenhouse gas molecules to other molecules via molecular collisions . Contrary to what is sometimes said, greenhouse gases do not "re-emit" photons after they are absorbed. Because each molecule experiences billions of collisions per second, any energy a greenhouse gas molecule receives by absorbing a photon will be redistributed to other molecules before there is a chance for

3220-416: Is usually balanced by water absorbed from the soil, humidity, or rain. When this balance is not maintained, often as a consequence of droughts , plants dry out and are therefore more flammable. A wildfire front is the portion sustaining continuous flaming combustion, where unburned material meets active flames, or the smoldering transition between unburned and burned material. As the front approaches,

3312-692: The 2023 Canadian wildfires false claims of arson gained traction on social media; however, arson is generally not a main cause of wildfires in Canada. In California, generally 6–10% of wildfires annually are arson. Coal seam fires burn in the thousands around the world, such as those in Burning Mountain , New South Wales; Centralia , Pennsylvania; and several coal-sustained fires in China . They can also flare up unexpectedly and ignite nearby flammable material. (Fire) Good luck deleting this, Frost! (Fire) The spread of wildfires varies based on

3404-965: The Amazon rainforest . The fires in the latter were caused mainly by illegal logging . The smoke from the fires expanded on huge territory including major cities, dramatically reducing air quality. As of August 2020, the wildfires in that year were 13% worse than in 2019 due primarily to climate change , deforestation and agricultural burning. The Amazon rainforest 's existence is threatened by fires. Record-breaking wildfires in 2021 occurred in Turkey , Greece and Russia , thought to be linked to climate change. The carbon released from wildfires can add to greenhouse gas concentrations. Climate models do not yet fully reflect this feedback . Wildfires release large amounts of carbon dioxide, black and brown carbon particles, and ozone precursors such as volatile organic compounds and nitrogen oxides (NOx) into

3496-569: The European Union . In 2020, the carbon released by California's wildfires was significantly larger than the state's other carbon emissions. Forest fires in Indonesia in 1997 were estimated to have released between 0.81 and 2.57 giga tonnes (0.89 and 2.83 billion short tons ) of CO 2 into the atmosphere, which is between 13–40% of the annual global carbon dioxide emissions from burning fossil fuels. In June and July 2019, fires in

3588-480: The Fire Information for Resource Management System (FIRMS). Between 2022–2023, wildfires throughout North America prompted an uptake in the delivery and design of various technologies using artificial intelligence for early detection, prevention, and prediction of wildfires. Wildfire suppression depends on the technologies available in the area in which the wildfire occurs. In less developed nations

3680-504: The Paris climate agreement . Due to the complex oxidative chemistry occurring during the transport of wildfire smoke in the atmosphere, the toxicity of emissions was indicated to increase over time. Atmospheric models suggest that these concentrations of sooty particles could increase absorption of incoming solar radiation during winter months by as much as 15%. The Amazon is estimated to hold around 90 billion tons of carbon. As of 2019,

3772-410: The dry season . In middle latitudes , the most common human causes of wildfires are equipment generating sparks (chainsaws, grinders, mowers, etc.), overhead power lines , and arson . Arson may account for over 20% of human caused fires. However, in the 2019–20 Australian bushfire season "an independent study found online bots and trolls exaggerating the role of arson in the fires." In

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3864-407: The thermal inertia of the climate system resists changes both day and night, as well as for longer periods. Diurnal temperature changes decrease with height in the atmosphere. In the lower portion of the atmosphere, the troposphere , the air temperature decreases (or "lapses") with increasing altitude. The rate at which temperature changes with altitude is called the lapse rate . On Earth,

3956-463: The Arctic emitted more than 140 megatons of carbon dioxide, according to an analysis by CAMS. To put that into perspective this amounts to the same amount of carbon emitted by 36 million cars in a year. The recent wildfires and their massive CO 2 emissions mean that it will be important to take them into consideration when implementing measures for reaching greenhouse gas reduction targets accorded with

4048-559: The Earth and its atmosphere emit longwave radiation . Sunlight includes ultraviolet , visible light , and near-infrared radiation. Sunlight is reflected and absorbed by the Earth and its atmosphere. The atmosphere and clouds reflect about 23% and absorb 23%. The surface reflects 7% and absorbs 48%. Overall, Earth reflects about 30% of the incoming sunlight, and absorbs the rest (240 W/m ). The Earth and its atmosphere emit longwave radiation , also known as thermal infrared or terrestrial radiation . Informally, longwave radiation

4140-420: The Earth are important because radiative transfer is the only process capable of exchanging energy between Earth and the rest of the universe. The temperature of a planet depends on the balance between incoming radiation and outgoing radiation. If incoming radiation exceeds outgoing radiation, a planet will warm. If outgoing radiation exceeds incoming radiation, a planet will cool. A planet will tend towards

4232-400: The Earth's greenhouse effect can also be measured as an energy flow change of 159 W/m . The greenhouse effect can be expressed as a fraction (0.40) or percentage (40%) of the longwave thermal radiation that leaves Earth's surface but does not reach space. Whether the greenhouse effect is expressed as a change in temperature or as a change in longwave thermal radiation, the same effect

4324-481: The Earth's greenhouse effect may be measured as a temperature change of 33 °C (59 °F). Thermal radiation is characterized by how much energy it carries, typically in watts per square meter (W/m ). Scientists also measure the greenhouse effect based on how much more longwave thermal radiation leaves the Earth's surface than reaches space. Currently, longwave radiation leaves the surface at an average rate of 398 W/m , but only 239 W/m reaches space. Thus,

4416-505: The United States in the early 20th century and fires were reported using telephones, carrier pigeons , and heliographs . Aerial and land photography using instant cameras were used in the 1950s until infrared scanning was developed for fire detection in the 1960s. However, information analysis and delivery was often delayed by limitations in communication technology. Early satellite-derived fire analyses were hand-drawn on maps at

4508-779: The Western US, earlier snowmelt and associated warming has also been associated with an increase in length and severity of the wildfire season, or the most fire-prone time of the year. A 2019 study indicates that the increase in fire risk in California may be partially attributable to human-induced climate change . In the summer of 1974–1975 (southern hemisphere), Australia suffered its worst recorded wildfire, when 15% of Australia's land mass suffered "extensive fire damage". Fires that summer burned up an estimated 117 million hectares (290 million acres ; 1,170,000 square kilometres ; 450,000 square miles ). In Australia,

4600-471: The air is less dense, there is less water vapor, and reduced pressure broadening of absorption lines limits the wavelengths that gas molecules can absorb. For any given wavelength, the longwave radiation that reaches space is emitted by a particular radiating layer of the atmosphere. The intensity of the emitted radiation is determined by the weighted average air temperature within that layer. So, for any given wavelength of radiation emitted to space, there

4692-435: The air over roads, rivers, and other barriers that may otherwise act as firebreaks . Torching and fires in tree canopies encourage spotting, and dry ground fuels around a wildfire are especially vulnerable to ignition from firebrands. Spotting can create spot fires as hot embers and firebrands ignite fuels downwind from the fire. In Australian bushfires , spot fires are known to occur as far as 20 kilometres (12 mi) from

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4784-416: The air temperature decreases by about 6.5 °C/km (3.6 °F per 1000 ft), on average, although this varies. The temperature lapse is caused by convection . Air warmed by the surface rises. As it rises, air expands and cools . Simultaneously, other air descends, compresses, and warms. This process creates a vertical temperature gradient within the atmosphere. This vertical temperature gradient

4876-410: The amount of longwave radiation emitted by the surface: Earth's surface temperature is often reported in terms of the average near-surface air temperature. This is about 15 °C (59 °F), a bit lower than the effective surface temperature. This value is 33 °C (59 °F) warmer than Earth's overall effective temperature. Energy flux is the rate of energy flow per unit area. Energy flux

4968-732: The annual number of hot days (above 35 °C) and very hot days (above 40 °C) has increased significantly in many areas of the country since 1950. The country has always had bushfires but in 2019, the extent and ferocity of these fires increased dramatically. For the first time catastrophic bushfire conditions were declared for Greater Sydney. New South Wales and Queensland declared a state of emergency but fires were also burning in South Australia and Western Australia. In 2019, extreme heat and dryness caused massive wildfires in Siberia , Alaska , Canary Islands , Australia , and in

5060-470: The atmosphere and thus contribute to the greenhouse effect . This creates a climate change feedback . Naturally occurring wildfires can have beneficial effects on those ecosystems that have evolved with fire. In fact, many plant species depend on the effects of fire for growth and reproduction. The ignition of a fire takes place through either natural causes or human activity (deliberate or not). Natural occurrences that can ignite wildfires without

5152-448: The atmosphere with greenhouse gases absorbs some of the longwave radiation being radiated upwards from lower layers. It also emits longwave radiation in all directions, both upwards and downwards, in equilibrium with the amount it has absorbed. This results in less radiative heat loss and more warmth below. Increasing the concentration of the gases increases the amount of absorption and emission, and thereby causing more heat to be retained at

5244-500: The atmosphere, with the main gases having no effect, and was largely due to water vapor, though small percentages of hydrocarbons and carbon dioxide had a significant effect. The effect was more fully quantified by Svante Arrhenius in 1896, who made the first quantitative prediction of global warming due to a hypothetical doubling of atmospheric carbon dioxide. The term greenhouse was first applied to this phenomenon by Nils Gustaf Ekholm in 1901. Matter emits thermal radiation at

5336-541: The atmosphere. As a result, global warming of about 1.2 °C (2.2 °F) has occurred since the Industrial Revolution , with the global average surface temperature increasing at a rate of 0.18 °C (0.32 °F) per decade since 1981. All objects with a temperature above absolute zero emit thermal radiation . The wavelengths of thermal radiation emitted by the Sun and Earth differ because their surface temperatures are different. The Sun has

5428-444: The atmosphere. These emissions affect radiation, clouds, and climate on regional and even global scales. Wildfires also emit substantial amounts of semi-volatile organic species that can partition from the gas phase to form secondary organic aerosol (SOA) over hours to days after emission. In addition, the formation of the other pollutants as the air is transported can lead to harmful exposures for populations in regions far away from

5520-492: The atmosphere." The enhanced greenhouse effect describes the fact that by increasing the concentration of GHGs in the atmosphere (due to human action), the natural greenhouse effect is increased. The term greenhouse effect comes from an analogy to greenhouses . Both greenhouses and the greenhouse effect work by retaining heat from sunlight, but the way they retain heat differs. Greenhouses retain heat mainly by blocking convection (the movement of air). In contrast,

5612-758: The best sites in Germany in its performance class. In 2006 over 2,300 hours at full load were achieved. Forest fire A wildfire , forest fire , or a bushfire is an unplanned, uncontrolled and unpredictable fire in an area of combustible vegetation . Depending on the type of vegetation present, a wildfire may be more specifically identified as a bushfire ( in Australia ), desert fire, grass fire, hill fire, peat fire, prairie fire, vegetation fire, or veld fire. Some natural forest ecosystems depend on wildfire. Wildfires are different from controlled or prescribed burning , which are carried out to provide

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5704-410: The decreasing concentration of water vapor, an important greenhouse gas. Rather than thinking of longwave radiation headed to space as coming from the surface itself, it is more realistic to think of this outgoing radiation as being emitted by a layer in the mid- troposphere , which is effectively coupled to the surface by a lapse rate . The difference in temperature between these two locations explains

5796-689: The difference between surface emissions and emissions to space, i.e., it explains the greenhouse effect. A greenhouse gas (GHG) is a gas which contributes to the trapping of heat by impeding the flow of longwave radiation out of a planet's atmosphere. Greenhouse gases contribute most of the greenhouse effect in Earth's energy budget . Gases which can absorb and emit longwave radiation are said to be infrared active and act as greenhouse gases. Most gases whose molecules have two different atoms (such as carbon monoxide, CO ), and all gases with three or more atoms (including H 2 O and CO 2 ), are infrared active and act as greenhouse gases. (Technically, this

5888-658: The direction of the fire, which can make fires particularly dangerous. For example, during the 1949 Mann Gulch fire in Montana , United States, thirteen smokejumpers died when they lost their communication links, became disoriented, and were overtaken by the fire. In the Australian February 2009 Victorian bushfires , at least 173 people died and over 2,029 homes and 3,500 structures were lost when they became engulfed by wildfire. Greenhouse effect The greenhouse effect occurs when greenhouse gases in

5980-697: The earth's atmosphere has 415 parts per million of carbon, and the destruction of the Amazon would add about 38 parts per million. Some research has shown wildfire smoke can have a cooling effect. Research in 2007 stated that black carbon in snow changed temperature three times more than atmospheric carbon dioxide. As much as 94 percent of Arctic warming may be caused by dark carbon on snow that initiates melting. The dark carbon comes from fossil fuels burning, wood and other biofuels, and forest fires. Melting can occur even at low concentrations of dark carbon (below five parts per billion)". Wildfire prevention refers to

6072-411: The economic and safety benefits of protecting structures and human life. The demand for timely, high-quality fire information has increased in recent years. Fast and effective detection is a key factor in wildfire fighting. Early detection efforts were focused on early response, accurate results in both daytime and nighttime, and the ability to prioritize fire danger. Fire lookout towers were used in

6164-466: The effect is even greater with carbon dioxide. The term greenhouse was first applied to this phenomenon by Nils Gustaf Ekholm in 1901. The greenhouse effect on Earth is defined as: "The infrared radiative effect of all infrared absorbing constituents in the atmosphere. Greenhouse gases (GHGs), clouds , and some aerosols absorb terrestrial radiation emitted by the Earth’s surface and elsewhere in

6256-402: The fire front. Especially large wildfires may affect air currents in their immediate vicinities by the stack effect : air rises as it is heated, and large wildfires create powerful updrafts that will draw in new, cooler air from surrounding areas in thermal columns . Great vertical differences in temperature and humidity encourage pyrocumulus clouds , strong winds, and fire whirls with

6348-417: The fire heats both the surrounding air and woody material through convection and thermal radiation . First, wood is dried as water is vaporized at a temperature of 100 °C (212 °F). Next, the pyrolysis of wood at 230 °C (450 °F) releases flammable gases. Finally, wood can smolder at 380 °C (720 °F) or, when heated sufficiently, ignite at 590 °C (1,000 °F). Even before

6440-452: The flames of a wildfire arrive at a particular location, heat transfer from the wildfire front warms the air to 800 °C (1,470 °F), which pre-heats and dries flammable materials, causing materials to ignite faster and allowing the fire to spread faster. High-temperature and long-duration surface wildfires may encourage flashover or torching : the drying of tree canopies and their subsequent ignition from below. Wildfires have

6532-421: The flammable material present, its vertical arrangement and moisture content, and weather conditions. Fuel arrangement and density is governed in part by topography , as land shape determines factors such as available sunlight and water for plant growth. Overall, fire types can be generally characterized by their fuels as follows: Wildfires occur when all the necessary elements of a fire triangle come together in

6624-441: The force of tornadoes at speeds of more than 80 kilometres per hour (50 mph). Rapid rates of spread, prolific crowning or spotting, the presence of fire whirls, and strong convection columns signify extreme conditions. Intensity also increases during daytime hours. Burn rates of smoldering logs are up to five times greater during the day due to lower humidity, increased temperatures, and increased wind speeds. Sunlight warms

6716-421: The greenhouse effect retains heat by restricting radiative transfer through the air and reducing the rate at which thermal radiation is emitted into space. The existence of the greenhouse effect, while not named as such, was proposed as early as 1824 by Joseph Fourier . The argument and the evidence were further strengthened by Claude Pouillet in 1827 and 1838. In 1856 Eunice Newton Foote demonstrated that

6808-454: The ground during the day which creates air currents that travel uphill. At night the land cools, creating air currents that travel downhill. Wildfires are fanned by these winds and often follow the air currents over hills and through valleys. Fires in Europe occur frequently during the hours of 12:00 p.m. and 2:00 p.m. Wildfire suppression operations in the United States revolve around

6900-495: The infrared signature of carbon dioxide produced by fires. Additional capabilities such as night vision , brightness detection, and color change detection may also be incorporated into sensor arrays . The Department of Natural Resources signed a contract with PanoAI for the installation of 360 degree 'rapid detection' cameras around the Pacific northwest, which are mounted on cell towers and are capable of 24/7 monitoring of

6992-477: The involvement of humans include lightning , volcanic eruptions , sparks from rock falls, and spontaneous combustions . Sources of human-caused fire may include arson, accidental ignition, or the uncontrolled use of fire in land-clearing and agriculture such as the slash-and-burn farming in Southeast Asia. In the tropics , farmers often practice the slash-and-burn method of clearing fields during

7084-456: The longwave radiation emitted by the surface, thus accumulating energy and warming the Earth's surface. The existence of the greenhouse effect, while not named as such, was proposed as early as 1824 by Joseph Fourier . The argument and the evidence were further strengthened by Claude Pouillet in 1827 and 1838. In 1856 Eunice Newton Foote demonstrated that the warming effect of the sun is greater for air with water vapour than for dry air, and

7176-427: The past 800,000 years, ice core data shows that carbon dioxide has varied from values as low as 180 ppm to the pre-industrial level of 270 ppm. Paleoclimatologists consider variations in carbon dioxide concentration to be a fundamental factor influencing climate variations over this time scale. Hotter matter emits shorter wavelengths of radiation. As a result, the Sun emits shortwave radiation as sunlight while

7268-484: The preemptive methods aimed at reducing the risk of fires as well as lessening its severity and spread. Prevention techniques aim to manage air quality, maintain ecological balances, protect resources, and to affect future fires. Prevention policies must consider the role that humans play in wildfires, since, for example, 95% of forest fires in Europe are related to human involvement. Wildfire prevention programs around

7360-422: The range of 4–100 microns. Greenhouse gases that were largely transparent to incoming solar radiation are more absorbent for some wavelengths in this range. The atmosphere near the Earth's surface is largely opaque to longwave radiation and most heat loss from the surface is by evaporation and convection . However radiative energy losses become increasingly important higher in the atmosphere, largely because of

7452-408: The retained energy goes into warming the oceans, with much smaller amounts going into heating the land, atmosphere, and ice. A simple picture assumes a steady state, but in the real world, the day/night ( diurnal ) cycle, as well as the seasonal cycle and weather disturbances, complicate matters. Solar heating applies only during daytime. At night the atmosphere cools somewhat, but not greatly because

7544-404: The risk and alter the behavior of wildfires dramatically. Years of high precipitation can produce rapid vegetation growth, which when followed by warmer periods can encourage more widespread fires and longer fire seasons. High temperatures dry out the fuel loads and make them more flammable, increasing tree mortality and posing significant risks to global forest health. Since the mid-1980s, in

7636-417: The size of the greenhouse effect. Different substances are responsible for reducing the radiation energy reaching space at different frequencies; for some frequencies, multiple substances play a role. Carbon dioxide is understood to be responsible for the dip in outgoing radiation (and associated rise in the greenhouse effect) at around 667 cm (equivalent to a wavelength of 15 microns). Each layer of

7728-558: The summit since 1929. This is a stone observation tower , which has extensive views over the Black Forest countryside and, on clear days, as far as the Alps , Vosges and Swabian Jura . Before the stone tower was built there had been wooden predecessor structures. The Black Forest Club maintains a hiking home and attached café on the Brandenkopf. The favourable location of the mountain, with its average wind speed oft 5.8 m/s at

7820-430: The surface and in the layers below. The power of outgoing longwave radiation emitted by a planet corresponds to the effective temperature of the planet. The effective temperature is the temperature that a planet radiating with a uniform temperature (a blackbody ) would need to have in order to radiate the same amount of energy. This concept may be used to compare the amount of longwave radiation emitted to space and

7912-399: The techniques used can be as simple as throwing sand or beating the fire with sticks or palm fronds. In more advanced nations, the suppression methods vary due to increased technological capacity. Silver iodide can be used to encourage snow fall, while fire retardants and water can be dropped onto fires by unmanned aerial vehicles , planes , and helicopters . Complete fire suppression

8004-936: The use of planes, helicopter, or UAVs can provide a wider view and may be sufficient to monitor very large, low risk areas. These more sophisticated systems employ GPS and aircraft-mounted infrared or high-resolution visible cameras to identify and target wildfires. Satellite-mounted sensors such as Envisat 's Advanced Along Track Scanning Radiometer and European Remote-Sensing Satellite 's Along-Track Scanning Radiometer can measure infrared radiation emitted by fires, identifying hot spots greater than 39 °C (102 °F). The National Oceanic and Atmospheric Administration 's Hazard Mapping System combines remote-sensing data from satellite sources such as Geostationary Operational Environmental Satellite (GOES), Moderate-Resolution Imaging Spectroradiometer (MODIS), and Advanced Very High Resolution Radiometer (AVHRR) for detection of fire and smoke plume locations. However, satellite detection

8096-422: The warming effect of the sun is greater for air with water vapour than for dry air, and the effect is even greater with carbon dioxide. She concluded that "An atmosphere of that gas would give to our earth a high temperature..." John Tyndall was the first to measure the infrared absorption and emission of various gases and vapors. From 1859 onwards, he showed that the effect was due to a very small proportion of

8188-411: The wildfires. While direct emissions of harmful pollutants can affect first responders and residents, wildfire smoke can also be transported over long distances and impact air quality across local, regional, and global scales. The health effects of wildfire smoke, such as worsening cardiovascular and respiratory conditions, extend beyond immediate exposure, contributing to nearly 16,000 annual deaths,

8280-519: The world may employ techniques such as wildland fire use (WFU) and prescribed or controlled burns . Wildland fire use refers to any fire of natural causes that is monitored but allowed to burn. Controlled burns are fires ignited by government agencies under less dangerous weather conditions. Other objectives can include maintenance of healthy forests, rangelands, and wetlands, and support of ecosystem diversity. Strategies for wildfire prevention, detection, control and suppression have varied over

8372-466: The years. One common and inexpensive technique to reduce the risk of uncontrolled wildfires is controlled burning : intentionally igniting smaller less-intense fires to minimize the amount of flammable material available for a potential wildfire. Vegetation may be burned periodically to limit the accumulation of plants and other debris that may serve as fuel, while also maintaining high species diversity. While other people claim that controlled burns and

8464-794: Was organized in South Africa's Kruger National Park to validate fire detection products including the new VIIRS active fire data. In advance of that campaign, the Meraka Institute of the Council for Scientific and Industrial Research in Pretoria, South Africa, an early adopter of the VIIRS 375 m fire product, put it to use during several large wildfires in Kruger. Since 2021 NASA has provided active fire locations in near real-time via

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