Landslides , also known as landslips , or rockslides , are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls , mudflows , shallow or deep-seated slope failures and debris flows . Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides .
97-691: The El Dorado Fire was a wildfire that burned 22,744 acres (9,204 ha; 35.538 sq mi; 92.04 km) in San Bernardino and Riverside counties of California from September to November 2020. It was ignited on September 5 by a pyrotechnic device at a gender reveal party in El Dorado Ranch Park; it quickly spread to the San Gorgonio Wilderness Area of the San Bernardino National Forest . Burning over
194-534: 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
291-403: A debris flow or mud flow . However, also dry debris can exhibit flow-like movement. Flowing debris or mud may pick up trees, houses and cars, and block bridges and rivers causing flooding along its path. This phenomenon is particularly hazardous in alpine areas, where narrow gorges and steep valleys are conducive of faster flows. Debris and mud flows may initiate on the slopes or result from
388-564: 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
485-465: 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
582-470: 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
679-456: A 71-day period, the fire destroyed 20 structures and resulted in one firefighter fatality, for which the couple hosting the party were charged with involuntary manslaughter . The fire began at 10:23 a.m. ( PDT ) on September 5, 2020, when Angela Renee Jimenez and Refugio Manuel Jimenez Jr. set off a smoke bomb at a gender reveal photoshoot at the El Dorado Ranch Park near Yucaipa , in southern San Bernardino County . The detonation of
776-663: 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
873-485: 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
970-466: A depth from few decimeters to some meters) is called a shallow landslide. Debris slides and debris flows are usually shallow. Shallow landslides can often happen in areas that have slopes with high permeable soils on top of low permeable soils. The low permeable soil traps the water in the shallower soil generating high water pressures. As the top soil is filled with water, it can become unstable and slide downslope. Deep-seated landslides are those in which
1067-610: 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
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#17330852141691164-458: A large amount of a country's gross domestic product which directly affects the country's economy. While costs vary wildly from year to year, depending on the severity of each fire season, in the United States, local, state, federal and tribal agencies collectively spend tens of billions of dollars annually to suppress wildfires. In the United States, it was reported that approximately $ 6 billion
1261-544: A low shearing resistance. On the slopes, some earthflow may be recognized by their elongated shape, with one or more lobes at their toes. As these lobes spread out, drainage of the mass increases and the margins dry out, lowering the overall velocity of the flow. This process also causes the flow to thicken. Earthflows occur more often during periods of high precipitation, which saturates the ground and builds up water pressures. However, earthflows that keep advancing also during dry seasons are not uncommon. Fissures may develop during
1358-530: 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
1455-415: 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
1552-545: 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
1649-503: 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,
1746-531: 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
1843-530: A reconstruction of the evolution of a particular landslide. Therefore, landslide hazard mitigation measures are not generally classified according to the phenomenon that might cause a landslide. Instead, they are classified by the sort of slope stabilization method used: Climate-change impact on temperature, both average rainfall and rainfall extremes, and evapotranspiration may affect landslide distribution, frequency and intensity (62). However, this impact shows strong variability in different areas (63). Therefore,
1940-681: 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
2037-542: A slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall , an earthquake , a slope cut to build a road, and many others), although this is not always identifiable. Landslides are frequently made worse by human development (such as urban sprawl ) and resource exploitation (such as mining and deforestation ). Land degradation frequently leads to less stabilization of soil by vegetation . Additionally, global warming caused by climate change and other human impact on
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#17330852141692134-569: 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
2231-779: 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
2328-430: A very wide range, from as low as 1 mm/yr to many km/h. Though these are a lot like mudflows , overall they are more slow-moving and are covered with solid material carried along by the flow from within. Clay, fine sand and silt, and fine-grained, pyroclastic material are all susceptible to earthflows. These flows are usually controlled by the pore water pressures within the mass, which should be high enough to produce
2425-448: 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
2522-719: Is an appropriate tool because it has functions of collection, storage, manipulation, display, and analysis of large amounts of spatially referenced data which can be handled fast and effectively. Cardenas reported evidence on the exhaustive use of GIS in conjunction of uncertainty modelling tools for landslide mapping. Remote sensing techniques are also highly employed for landslide hazard assessment and analysis. Before and after aerial photographs and satellite imagery are used to gather landslide characteristics, like distribution and classification, and factors like slope, lithology , and land use/land cover to be used to help predict future events. Before and after imagery also helps to reveal how
2619-434: Is determined by certain geologic factors, and that future landslides will occur under the same conditions as past events. Therefore, it is necessary to establish a relationship between the geomorphologic conditions in which the past events took place and the expected future conditions. Natural disasters are a dramatic example of people living in conflict with the environment. Early predictions and warnings are essential for
2716-514: Is essentially due to a decrease in the shear strength of the slope material, an increase in the shear stress borne by the material, or a combination of the two. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Natural causes of landslides include: Landslides are aggravated by human activities, such as: In traditional usage, the term landslide has at one time or another been used to cover almost all forms of mass movement of rocks and regolith at
2813-457: Is fluid-like and generally much more rapid. This is usually a result of lower shear resistances and steeper slopes. Typically, debris slides start with the detachment of large rock fragments high on the slopes, which break apart as they descend. Clay and silt slides are usually slow but can experience episodic acceleration in response to heavy rainfall or rapid snowmelt. They are often seen on gentle slopes and move over planar surfaces, such as over
2910-721: 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
3007-473: 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
El Dorado Fire - Misplaced Pages Continue
3104-544: Is provided below. Under this classification, six types of movement are recognized. Each type can be seen both in rock and in soil. A fall is a movement of isolated blocks or chunks of soil in free-fall. The term topple refers to blocks coming away by rotation from a vertical face. A slide is the movement of a body of material that generally remains intact while moving over one or several inclined surfaces or thin layers of material (also called shear zones) in which large deformations are concentrated. Slides are also sub-classified by
3201-416: 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,
3298-632: 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. The spread of wildfires varies based on
3395-957: 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
3492-557: 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
3589-472: 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
3686-500: 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,
3783-410: 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
3880-459: 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
3977-462: The Earth's surface. In 1978, geologist David Varnes noted this imprecise usage and proposed a new, much tighter scheme for the classification of mass movements and subsidence processes. This scheme was later modified by Cruden and Varnes in 1996, and refined by Hutchinson (1988), Hungr et al. (2001), and finally by Hungr, Leroueil and Picarelli (2014). The classification resulting from the latest update
El Dorado Fire - Misplaced Pages Continue
4074-442: 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
4171-767: 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,
4268-435: 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
4365-720: 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
4462-626: The area of the Val Pola disaster (Italy). Evidence of past landslides has been detected on many bodies in the solar system, but since most observations are made by probes that only observe for a limited time and most bodies in the solar system appear to be geologically inactive not many landslides are known to have happened in recent times. Both Venus and Mars have been subject to long-term mapping by orbiting satellites, and examples of landslides have been observed on both planets. Landslide mitigation refers to several human-made activities on slopes with
4559-470: 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
4656-444: 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
4753-584: The death of a single firefighter and 13 other injuries; 20 buildings were destroyed. State Route 38 was reopened on September 29, 2020. Some areas of the SBNF remained closed until April 2022. The El Dorado Fire burned steep mountain terrain already prone to landslide , rockfall, and debris flow hazards. Landslides and rockfalls began in September 2020 as the fire eroded the soil of its burn scar, and plagued San Bernardino County during and after its duration. Storms and
4850-579: The development of guidelines for sustainable land-use planning . The analysis is used to identify the factors that are related to landslides, estimate the relative contribution of factors causing slope failures, establish a relation between the factors and landslides, and to predict the landslide hazard in the future based on such a relationship. The factors that have been used for landslide hazard analysis can usually be grouped into geomorphology , geology , land use/land cover, and hydrogeology . Since many factors are considered for landslide hazard mapping, GIS
4947-595: 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. The suppression of wild fires takes up
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#17330852141695044-678: The dismissal of all charges against them in December 2021 and again in October 2022. The judge denied the dismissal of most of the charges both times. On January 23, 2023, a Superior Court judge in San Bernardino dismissed one charge out of 30 against the Jimenezes. On February 9, 2024, after pleading guilty to one felony count of involuntary manslaughter and two felony counts of recklessly causing fire to an inhabited structure, Refugio Manuel Jimenez Jr.
5141-693: 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
5238-411: 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
5335-468: The effects of climate change on landslides need to be studied on a regional scale. Climate change can have both positive and negative impacts on landslides Temperature rise may increase evapotranspiration, leading to a reduction in soil moisture and stimulate vegetation growth, also due to a CO2 increase in the atmosphere. Both effects may reduce landslides in some conditions. On the other side, temperature rise causes an increase of landslides due to Since
5432-406: The environment , can increase the frequency of natural events (such as extreme weather ) which trigger landslides. Landslide mitigation describes the policy and practices for reducing the risk of human impacts of landslides, reducing the risk of natural disaster . Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This
5529-402: 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
5626-427: The fire had grown to 22,604 acres (9,148 ha), but was estimated to be 81 percent contained and the evacuation order for Angelus Oaks was lifted. Containment reached 93 percent on September 28, and it continued to burn until November 16. The El Dorado Fire burned 22,744 acres (9,204 ha) over 71 days, reaching its maximum extent by September 29. It cost $ 42,269,660 to suppress. The fire resulted in
5723-417: 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
5820-731: The fire's spread, California Governor Gavin Newsom declared a state of emergency in San Bernardino County, and evacuations were ordered in Mountain Home Village , Oak Glen , Forest Falls , and Yucaipa. A 12-mile (19 km) stretch of California State Route 38 and the San Gorgonio Wilderness Area of the San Bernardino National Forest (SBNF) were closed. On September 7, the fire grew to 9,671 acres (3,914 ha). Firefighters halted its advance south, though evacuation notices were issued to residents of Riverside County , to
5917-452: 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
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#17330852141696014-421: 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
6111-452: The fluidization of landslide material as it gains speed or incorporates further debris and water along its path. River blockages as the flow reaches a main stream can generate temporary dams. As the impoundments fail, a domino effect may be created, with a remarkable growth in the volume of the flowing mass, and in its destructive power. An earthflow is the downslope movement of mostly fine-grained material. Earthflows can move at speeds within
6208-441: 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
6305-713: The form of the surface(s) or shear zone(s) on which movement happens. The planes may be broadly parallel to the surface ("planar slides") or spoon-shaped ("rotational slides"). Slides can occur catastrophically, but movement on the surface can also be gradual and progressive. Spreads are a form of subsidence, in which a layer of material cracks, opens up, and expands laterally. Flows are the movement of fluidised material, which can be both dry or rich in water (such as in mud flows). Flows can move imperceptibly for years, or accelerate rapidly and cause disasters. Slope deformations are slow, distributed movements that can affect entire mountain slopes or portions of it. Some landslides are complex in
6402-462: The goal of lessening the effect of landslides. Landslides can be triggered by many, sometimes concomitant causes. In addition to shallow erosion or reduction of shear strength caused by seasonal rainfall , landslides may be triggered by anthropic activities, such as adding excessive weight above the slope, digging at mid-slope or at the foot of the slope. Often, individual phenomena join to generate instability over time, which often does not allow
6499-450: 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
6596-490: 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
6693-470: 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
6790-480: The landscape changed after an event, what may have triggered the landslide, and shows the process of regeneration and recovery. Using satellite imagery in combination with GIS and on-the-ground studies, it is possible to generate maps of likely occurrences of future landslides. Such maps should show the locations of previous events as well as clearly indicate the probable locations of future events. In general, to predict landslides, one must assume that their occurrence
6887-440: The long runout can be different, but they typically result in the weakening of the sliding mass as the speed increases. The causes of this weakening are not completely understood. Especially for the largest landslides, it may involve the very quick heating of the shear zone due to friction, which may even cause the water that is present to vaporize and build up a large pressure, producing a sort of hovercraft effect. In some cases,
6984-413: The most important factors that trigger landslides in any given location. Using GIS, extremely detailed maps can be generated to show past events and likely future events which have the potential to save lives, property, and money. Since the ‘90s, GIS have been also successfully used in conjunction to decision support systems , to show on a map real-time risk evaluations based on monitoring data gathered in
7081-431: The movement of a mass over a planar or curvilinear surface or shear zone. A debris slide is a type of slide characterized by the chaotic movement of material mixed with water and/or ice. It is usually triggered by the saturation of thickly vegetated slopes which results in an incoherent mixture of broken timber, smaller vegetation and other debris. Debris flows and avalanches differ from debris slides because their movement
7178-471: The movement of clayey materials, which facilitate the intrusion of water into the moving mass and produce faster responses to precipitation. A rock avalanche, sometimes referred to as sturzstrom , is a large and fast-moving landslide of the flow type. It is rarer than other types of landslides but it is often very destructive. It exhibits typically a long runout, flowing very far over a low-angle, flat, or even slightly uphill terrain. The mechanisms favoring
7275-451: The negative impacts felt by landslides. GIS offers a superior method for landslide analysis because it allows one to capture, store, manipulate, analyze, and display large amounts of data quickly and effectively. Because so many variables are involved, it is important to be able to overlay the many layers of data to develop a full and accurate portrayal of what is taking place on the Earth's surface. Researchers need to know which variables are
7372-480: 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
7469-402: The reduction of property damage and loss of life. Because landslides occur frequently and can represent some of the most destructive forces on earth, it is imperative to have a good understanding as to what causes them and how people can either help prevent them from occurring or simply avoid them when they do occur. Sustainable land management and development is also an essential key to reducing
7566-404: 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
7663-489: The sense that they feature different movement types in different portions of the moving body, or they evolve from one movement type to another over time. For example, a landslide can initiate as a rock fall or topple and then, as the blocks disintegrate upon the impact, transform into a debris slide or flow. An avalanching effect can also be present, in which the moving mass entrains additional material along its path. Slope material that becomes saturated with water may produce
7760-412: The sliding surface is mostly deeply located, for instance well below the maximum rooting depth of trees. They usually involve deep regolith , weathered rock, and/or bedrock and include large slope failures associated with translational, rotational, or complex movements. They tend to form along a plane of weakness such as a fault or bedding plane . They can be visually identified by concave scarps at
7857-466: The smoke bomb lit nearby dry grass on fire, which spread rapidly. According to the California Department of Forestry and Fire Protection (CAL FIRE), the Jimenezes attempted to extinguish the fire with bottled water, then reported the fire to the authorities and cooperated with their investigation. The cause of the fire inspired widespread mockery and condemnation against gender reveal parties, and
7954-595: The south of San Bernardino County, and the SBNF was closed. Lower temperatures and higher humidity on September 8 briefly slowed the spread of the El Dorado Fire, which grew to 11,259 acres (4,556 ha) and prompted more evacuations in San Bernardino County. On September 9, the annual Santa Ana winds fanned the El Dorado Fire, which grew to 14,043 acres (5,683 ha) by the morning of September 12. In spite of winds, continued high temperatures, and low humidity, firefighters made enough progress containing
8051-452: The spread of the El Dorado Fire to allow for the lifting of evacuation orders in Yucaipa and Oak Glen on September 10, September 11, September 12, and September 13, and Riverside County on September 10. Angelus Oaks and Forest Falls were evacuated at the same time, however, and residents of Big Bear were advised to evacuate. On September 15, CAL FIRE estimated that
8148-587: The spread of the fire, then at 17,892 acres (7,241 ha), was 61 percent contained. On September 17 the El Dorado Fire crossed State Route 38 and grew to 21,678 acres (8,773 ha) by the next day. While U.S. Forest Service Hotshot crews conducted controlled burns near Angelus Oaks on September 17, wind gusts created local fires that resulted in the death of a firefighter. On September 18 residents of Forest Falls and Mountain Home Village were allowed to return to their homes. By September 24,
8245-399: 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
8342-560: The threat of mudflows triggered evacuation orders and advisories for communities in San Bernardino and Riverside Counties in January 2021, July 2021, December 2021, and September 2022. The San Bernardino County District Attorney's Office began assembling a case for the prosecution of the Jimenezes in January 2021. The couple were formally charged with involuntary manslaughter , a felony , among other felony and misdemeanor charges on July 20, 2021; they pleaded not guilty. The Jimenezes requested
8439-716: The top and steep areas at the toe. Deep-seated landslides also shape landscapes over geological timescales and produce sediment that strongly alters the course of fluvial streams . Landslides that occur undersea, or have impact into water e.g. significant rockfall or volcanic collapse into the sea, can generate tsunamis . Massive landslides can also generate megatsunamis , which are usually hundreds of meters high. In 1958, one such tsunami occurred in Lituya Bay in Alaska. Landslide hazard analysis and mapping can provide useful information for catastrophic loss reduction, and assist in
8536-413: The underlying bedrock. Failure surfaces can also form within the clay or silt layer itself, and they usually have concave shapes, resulting in rotational slides Slope failure mechanisms often contain large uncertainties and could be significantly affected by heterogeneity of soil properties. A landslide in which the sliding surface is located within the soil mantle or weathered bedrock (typically to
8633-936: 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
8730-474: The very high temperature may even cause some of the minerals to melt. During the movement, the rock in the shear zone may also be finely ground, producing a nanometer-size mineral powder that may act as a lubricant, reducing the resistance to motion and promoting larger speeds and longer runouts. The weakening mechanisms in large rock avalanches are similar to those occurring in seismic faults. Slides can occur in any rock or soil material and are characterized by
8827-411: 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,
8924-519: 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
9021-466: 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
9118-540: Was frequently compared to the 2017 Sawmill Fire , ignited by an exploding target at a gender reveal party in Arizona. First responders arrived and began to attempt suppression of the El Dorado Fire at 10:40 a.m., when it had an area of five acres (2.0 ha). Because of the steep terrain, temperatures exceeding 100 °F (38 °C), and low humidity, the fire spread rapidly northward and grew to an area of 7,050 acres (2,850 ha) on September 6. In response to
9215-762: 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
9312-431: Was sentenced to one year in county jail and two years of felony probation and community service. Angelina Jimenez, who pleaded guilty to three misdemeanor counts of recklessly causing a fire to another's property, was sentenced to one year of summary probation and community service. Additionally, the couple was ordered to pay $ 1,789,972 in restitution to victims of the fire. Wildfire A wildfire , forest fire , or
9409-457: Was spent between 2004–2008 to suppress wildfires in the country. In California, the U.S. Forest Service spends about $ 200 million per year to suppress 98% of wildfires and up to $ 1 billion to suppress the other 2% of fires that escape initial attack and become large. Landslide Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make
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