Contrail, Wikipedia Contrail, Wikipedia
Contrail, Wikipedia 
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http://en.wikipedia.org/wiki/Contrail
Contrails (short for "condensation trails") or vapour trails are visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets. If the air is cold enough, this trail will comprise tiny ice crystals.
The wingtip vortices which trail from the wingtips and wing flaps of aircraft are sometimes partly visible due to condensation in the cores of the vortices. Each vortex is a mass of spinning air and the air pressure at the centre of the vortex is very low. These wingtip vortices are unrelated to the exhaust from the engines. They are sometimes known as vapour trails. Depending on atmospheric conditions, contrails may be visible for only a few minutes.[1]
Condensation from engine exhaust
The main products of hydrocarbon fuel combustion are carbon dioxide and water vapor. At high altitudes this water vapour emerges into a cold environment, and the local increase in water vapour can push the water content of the air past saturation point. The vapour then condenses into tiny water droplets and/or deposits into ice. These millions of tiny water droplets and/or ice crystals form the vapour trail or contrails. The energy drop (and therefore, time and distance) the vapour needs to condense accounts for the contrail forming some way behind the aircraft's engines. The majority of the cloud content comes from water trapped in the surrounding air.[citation needed] At high altitudes, supercooled water vapour requires a trigger to encourage deposition or condensation. The exhaust particles in the aircraft's exhaust act as this trigger, causing the trapped vapour to rapidly turn to ice crystals. Exhaust vapour trails or contrails usually occur above 8000 metres (26,000 feet). where the temperature is below -40°C (-40°F).[2]
When a wing is generating lift it causes a vortex to form at each wingtip, and sometimes also at the tip of each wing flap. These wingtip vortices persist in the atmosphere long after the aircraft has past. The reduction in pressure and temperature across each vortex can cause water to condense and make the cores of the wingtip vortices visible. This effect is more common on humid days. Wingtip vortices can sometimes be seen behind the wing flaps of airliners during takeoff and landing, and during landing of the Space shuttle.
The visible cores of wingtip vortices contrast with the other major type of contrails which are caused by the combustion of fuel. Contrails produced from jet engine exhaust are seen at high altitude, directly behind each engine. In contrast, the visible cores of wingtip vortices are usually seen only at low altitude where the aircraft is travelling slowly after takeoff or before landing, and where the ambient humidity is higher. They trail behind the wingtips and wing flaps rather than behind the engines.
The air inside the intake of a turbo-fan engine is at a lower pressure than the surrounding air, particularly during high-thrust settings, and may result in a condensation fog forming inside the intake.
Vapour trails or contrails, by affecting the Earth's radiation balance, act as a radiative forcing. Studies have found that vapour trails or contrails trap outgoing longwave radiation emitted by the Earth and atmosphere (positive radiative forcing) at a greater rate than they reflect incoming solar radiation (negative radiative forcing). Therefore, the overall net effect of contrails is positive, i.e. a warming.[3] However, the effect varies daily and annually, and overall the magnitude of the forcing is not well known: globally (for 1992 air traffic conditions), values range from 3.5 mW/m² to 17 mW/m². Other studies have determined that night flights are mostly responsible for the warming effect: while accounting for only 25% of daily air traffic, they contribute 60 to 80% of contrail radiative forcing. Similarly, winter flights account for only 22% of annual air traffic, but contribute half of the annual mean radiative forcing.[4]
Chemtrail conspiracy theory, Wikiped... LCD
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http://en.wikipedia.org/wiki/Chemtrails
The chemtrail conspiracy theory holds that some contrails are actually chemicals or biological agents deliberately sprayed at high altitudes for a purpose undisclosed to the general public. Versions of the chemtrail conspiracy theory circulating on the internet and radio talk shows theorize that the activity is directed by government officials.[citation needed] As a result, federal agencies have received thousands of complaints from people who have demanded an explanation.[1] The existence of chemtrails has been repeatedly denied by government agencies and scientists around the world.[2]
The United States Air Force has stated that the theory is a hoax which "has been investigated and refuted by many established and accredited universities, scientific organizations, and major media publications".[3] The British Department for Environment, Food and Rural Affairs has stated that chemtrails "are not scientifically recognised phenomena".[4] The Canadian Government House Leader has stated that "The term 'chemtrails' is a popularized expression, and there is no scientific evidence to support their existence."[5]
The term chemtrail is derived from "chemical trail" in the similar fashion that contrail is an abbreviation for condensation trail. It does not refer to common forms of aerial spraying such as crop dusting, cloud seeding or aerial firefighting. The term specifically refers to aerial trails allegedly caused by the systematic high-altitude release of chemical substances not found in ordinary contrails, resulting in the appearance of supposedly uncharacteristic sky tracks. Believers of this theory speculate that the purpose of the chemical release may be for global dimming, population control, weather control, or biowarfare and claim that these trails are causing respiratory illnesses and other health problems.[6]
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The chemtrail conspiracy theory began to circulate in 1996 when the United States Air Force (USAF) was accused of "spraying the US population with mysterious substances" from aircraft "generating unusual contrail patterns" .[3] The Air Force says the hoax was fueled in part by authors citing an Air University strategy paper entitled Weather as a Force Multiplier: Owning the Weather in 2025 to allege the Air Force was currently conducting a secret government program to modify the weather.[7] The paper was presented in response to a military directive to anticipate future developments and strategies for maintaining the United States' military dominance in the year 2025 and identified as "fictional representations of future situations/scenarios".[7] The Air Force has stated that the "purpose of that paper was part of a thesis to outline a strategy for the use of a future weather modification system to achieve military objectives" and that the paper "does not reflect current military policy, practice, or capability."[3][8]The Air Force has stated that its policy is to "observe and forecast the weather" so that the "information can be used to support military operations" and that it is "not conducting any weather modification experiments or programs and has no plans to do so in the future".[3] Additionally, the Air Force states that the "'Chemtrail' hoax has been investigated and refuted by many established and accredited universities, scientific organizations, and major media publications."[3]
In Britain, when the Secretary of State for Environment, Food and Rural Affairs was asked "what research her Department has undertaken into the polluting effects of chemtrails for aircraft", the response was that "the Department is not researching into chemtrails from aircraft as they are not scientifically recognised phenomena."[9][10][4] An IPCC special report AVIATION AND THE GLOBAL ATMOSPHERE published in 1999, states that "aircraft line-shaped contrails are estimated to cover about 0.1% of the Earth’s surface" and that the "contrail cover is projected to grow to 0.5% by 2050."[4][11] The report also states that contrails tend to warm the Earth’s surface, similar to thin high clouds.[11]
In a response to a petition by concerned Canadian citizens regarding "chemicals used in aerial sprayings are adversely affecting the health of Canadians," the Government House Leader responded by stating that "There is no substantiated evidence, scientific or otherwise, to support the allegation that there is high altitude spraying conducted in Canadian airspace. The term 'chemtrails' is a popularized expression, and there is no scientific evidence to support their existence." [12] [5][13][14] The house leader goes on to say that "it is our belief that the petitioners are seeing regular airplane condensation trails, or contrails."[5]
Various versions of the chemtrail conspiracy theory have circulated through internet websites and radio programs.[15] In some of the accounts, the chemicals are described as barium and aluminum salts, polymer fibers, thorium, or silicon carbide.[16] In other accounts it is alleged the skies are being seeded with electrical conductive materials as part of a massive electromagnetic superweapons program based around the High Frequency Active Auroral Research Program (HAARP).[17] Those who believe in the conspiracy say the chemtrails are toxic,[18] but the reasons given by those who believe in the conspiracy vary widely, spanning from military weapons testing, chemical population control, to global warming mitigation measures.[19] Federal agencies and scientists have consistently denied that chemtrails exist, insisting the sky tracks are simply persistent contrails.[16] As the chemtrail conspiracy theory spread, federal officials were flooded with angry calls and letters.[16] A multi-agency response to dispel the rumors was published in a 2000 fact sheet by the Environmental Protection Agency (EPA), the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA) and the National Oceanic and Atmospheric Administration (NOAA), a step many chemtrail believers have interpeted as further evidence of the existence of a government cover-up.[16]
Proponents of the chemtrail theory say that chemtrails can be distinguished from contrails by their long duration, asserting that the chemtrails are those skytracks that persist for as much as a half day or transform into cirrus-like clouds.[19] However, some contrails are visible for several hours according to Contrails facts, a USAF publication.[3] Air Force officials say that long lasting contrails result from certain atmospheric conditions, and their duration and rate of dissipation can be accurately predicted when humidity level and temperature are known.[3]
Contrails can be visible for several hours [3] but chemtrail conspiricists try to differentiate chemtrails from contrails by describing them as streams that sometimes persist in the sky for hours, and which sometimes trace criss-crossing, grid-like patterns, or parallel stripes which eventually blend to form large clouds. Another feature that proponents say distinguishes a chemtrail from a contrail is the presence of visible color prisms in the streams, unusual concentrations of sky tracks in a single area, or lingering tracks left by unmarked or military airplanes flying in atypical altitudes or locations.[15][16][20][21] [22]
Government agencies and other experts on contrail or atmospheric phenomena deny the existence of chemtrails, insisting that the characteristics attributed to them are simply features of contrails responding differently in diverse conditions in terms of the sunlight, temperature, horizontal and vertical wind shear, and humidity levels present at the aircraft's altitude.[3][15][16][20][21] These experts respond that what appears as patterns such as grids formed by contrails result from increased air traffic traveling through the gridlike United States National Airspace System's north-south and east-west oriented flight lanes, and that it is difficult for observers to judge the differences in altitudes between these contrails from the ground.[3] The jointly published fact sheet produced by NASA, the EPA, the FAA, and NOAA in 2000 in response to alarms over chemtrails details the science of contrail formation, and outlines both the known and potential impacts contrails have on temperature and climate.[23] The USAF produced a fact sheet as well that described these contrail phenomena as observed and analyzed since at least 1953. It also rebutted chemtrails' theories more directly by characterizing the theories as a hoax and denying the existence of any chemtrails.[3][16]
Patrick Minnis, an atmospheric scientist with NASA's Langley Research Center in Hampton, Virginia, is quoted in USA Today as saying that logic is not exactly a real selling point for most chemtrail proponents: "If you try to pin these people down and refute things, it's, 'Well, you're just part of the conspiracy', he said."[15]
In 2001, United States Congressman Dennis Kucinich introduced legislation that would have permanently prohibited the basing of weapons in space, and he listed chemtrails as one of a number of exotic weapons that would be banned.[24] Proponents have asserted that because explicit reference to chemtrails was entered by Congressman Kucinich into the congressional record, this constitutes official government acknowledgement of their existence.[21][25] But that bill received an unfavorable evaluation from the United States Department of Defense and died in committee,[26] with no mention of chemtrails appearing in the text of any of the three subsequent failed attempts by Kucinich to enact a Space Preservation Act.
http://en.wikipedia.org/wiki/Chemtrails
Cloud seeding, Weather modification,... LCD
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http://en.wikipedia.org/wiki/Cloud_Seeding
Cloud seeding, a form of weather modification, is the attempt to change the amount or type of precipitation that falls from clouds, by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud. The usual intent is to increase precipitation (rain or snow), but hail and fog suppression are also widely practiced in airports.
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The most common chemicals used for cloud seeding include silver iodide and dry ice (frozen carbon dioxide). The expansion of liquid propane into a gas has also been used and can produce ice crystals at warmer temperatures than silver iodide. The use of hygroscopic materials, such as salt, is increasing in popularity because of some promising research results.
Seeding of clouds requires that they contain supercooled liquid water—that is, liquid water colder than zero degrees Celsius. Introduction of a substance such as silver iodide, which has a crystalline structure similar to that of ice, will induce freezing nucleation. Dry ice or propane expansion cools the air to such an extent that ice crystals can nucleate spontaneously from the vapor phase. Unlike seeding with silver iodide, this spontaneous nucleation does not require any existing droplets or particles because it produces extremely high vapor supersaturations near the seeding substance. However, the existing droplets are needed for the ice crystals to grow into large enough particles to precipitate out.
In mid-latitude clouds, the usual seeding strategy has been predicated upon the fact that the equilibrium vapor pressure is lower over ice than over water. When ice particles form in supercooled clouds, this fact allows the ice particles to grow at the expense of liquid droplets. If there is sufficient growth, the particles become heavy enough to fall as snow (or, if melting occurs, rain) from clouds that otherwise would produce no precipitation. This process is known as "static" seeding.
Seeding of warm-season or tropical cumuliform (convective) clouds seeks to exploit the latent heat released by freezing. This strategy of "dynamic" seeding assumes that the additional latent heat adds buoyancy, strengthens updrafts, ensures more low-level convergence, and ultimately causes rapid growth of properly selected clouds.
Cloud seeding chemicals may be dispersed by aircraft (as in the second figure) or by dispersion devices located on the ground (generators, as in first figure, or canisters fired from anti-aircraft guns or rockets). For release by aircraft, silver iodide flares are ignited and dispersed as an aircraft flies through the inflow of a cloud. When released by devices on the ground, the fine particles are carried downwind and upwards by air currents after release.
Referring to the 1903, 1915, 1919 and 1944 and 1947 weather modification experiments, the Federation of Meterology discounted "rain making". By the 1950s the CSIRO Division of Radiophysics switched to investigating the physics of clouds and had hoped by 1957 to be masters of the weather. By the 1960s the dreams of weather making had truly faded only to be re-ignited post-corporatisation of the Snowy Mountains Scheme in order to achieve "above target" water for energy generation and profits.
While cloud seeding has shown to be effective in altering cloud structure and size, and converting cloud water to ice particles, it is more controversial whether cloud seeding increases the amount of precipitation at the ground. Cloud seeding may also suppress precipitation.[citation needed]
Part of the problem is that it is difficult to discern how much precipitation would have occurred had the cloud not been seeded. There are no discernible "traces" of the effectiveness of recent cloud seeding in the Snowy Mountains Australia. Nevertheless, there is hope that winter cloud seeding over mountains will produce snow. This statement arises from partial interpretation of professional societies Weather Modification Association, World Meteorological Organization, and American Meteorological Society (AMS). The AMS states that there is statistical evidence for seasonal precipitation increases of about 10% with winter seeding [1], however, this clearly does not apply to all cloud seeding activities. The World Meteorological Organization has indicated that cloud seeding does not produce positive results in all cases and is dependent on specificity of clouds, wind speed and direction, terrain and other factors.
The National Center for Atmospheric Research (NCAR), an institution in Boulder, Colorado, has made some statistical analysis of seeded and unseeded clouds in an attempt to understand the differences between them. They have conducted seeding research in several countries that include Mali, Saudi Arabia, Mexico, South Africa, Thailand, Italy, and Argentina.
It has also been said that in the 2008 summer Olympics in Beijing clouds were seeded so that there will be no rain during the opening ceremony.[1] The Chinese weather modification office rarely publishes in the open scientific literature and therefore their claims of success are widely disputed.
With an NFPA 704 rating of Blue 2, silver iodide can cause temporary incapacitation or possible residual injury (e.g., chloroform) with intense or continued but not chronic exposure. However, there have been several detailed ecological studies that showed negligible environmental and health impacts. [2][3][4]. The toxicity of silver and silver compounds (from silver iodide) was shown to be of low order in some studies. These findings likely result from the minute amounts of silver generated by cloud seeding, which are 100 times less than industry emissions into the atmosphere in many parts of the world, or individual exposure from tooth fillings[5].
Accumulations in the soil, vegetation, and surface runoff have not been large enough to measure above natural background[6]. A 1995 environmental assessment in the Sierra Nevada of California[7] and a 2004 independent panel of experts in Australia confirmed these earlier findings. The paper does include the names of the experts, their scientific qualifications or published research papers to support the assertion that cloud seeding will have no ecotoxic impacts or affect alpine waterways.
Cloud seeding over Kosciuszko National Park - a Biosphere Reserve - is problematic in that several rapid changes of environmental legislation were made to enable the "trial". Environmentalists are concerned about the uptake of silver in a highly sensitive environment affecting the pygmy possum amongst other species as well as recent high level algal blooms in once pristine glacial lakes. The ABC program Earthbeat on 17 July 2004 heard that not every cloud has a silver lining where concerns for the health of the pygmy possums was raised. Earlier research and analysis by the former Snowy Mountains Authority led to the cessation of the cloud seeding program in the 1950s with non-definitive results (http://cires.colorado.edu/~aslater/snowy.html). Formerly, cloud seeding was rejected in Australia on environmental grounds because of concerns about the protected species, the pygmy possum. (http://www.colongwilderness.org.au/RedIndex/NSW/Jagu99.htm)
Vincent Schaefer (1906–1993) discovered the principle of cloud seeding in July 1946 through a series of serendipitous events. Following ideas generated between himself and Nobel laureate Irving Langmuir while climbing Mt. Washington in New Hampshire, Schaefer, Langmuir's research associate, created a way of experimenting with supercooled clouds using a deep freeze unit lined with black velveteen. He tried hundreds of potential agents to stimulate ice crystal growth, i.e., salt, talcum powder, soils, dust and various chemical agents with minor effect. Then one hot and humid July day he wanted to try a few experiments at General Electric's Schenectady Research Lab. He was dismayed to find that the deep freezer was not cold enough to produce a cloud using breath air. He decided to move the process along by adding a chunk of dry ice just to lower the temperature. To his astonishment, as soon as he breathed into the chamber, a bluish haze was noted, followed by an eye-popping display of millions of tiny ice crystals, reflecting the strong light rays illuminating a cross-section of the chamber. He instantly realized that he had discovered a way to change supercooled water into ice crystals. The experiment was easily replicated and he explored the temperature gradient to establish the −40˚C[8] limit for liquid water. Within the month, Schaefer's colleague, the noted atmospheric scientist Dr. Bernard Vonnegut (brother of novelist Kurt Vonnegut) is credited with discovering another method for "seeding" supercooled cloud water. Vonnegut accomplished his discovery at the desk, looking up information in a basic chemistry text and then tinkering with silver and iodide chemicals to produce silver iodide. Both methods were adopted for use in cloud seeding during 1946 while working for the General Electric Corporation in the state of New York. Schaefer's altered a cloud's heat budget, Vonnegut's altered formative crystal structure – an ingenious property related to a good match in lattice constant between the two types of crystal. (The crystallography of ice later played a role in Kurt Vonnegut's novel Cat's Cradle.) The first attempt to modify natural clouds in the field through "cloud seeding" began during a flight that began in upstate New York on 13 November 1946. Schaefer was able to cause snow to fall near Mount Greylock in western Massachusetts, after he dumped six pounds of dry ice into the target cloud from a plane after a 60 mile easterly chase from the Schenectady County Airport.[9]
Dry ice and silver iodide agents are effective in changing the physical chemistry of supercooled clouds, thus useful in augmentation of winter snowfall over mountains and under certain conditions, lightning and hail suppression. While not a new technique hygroscopic seeding for enhancement of rainfall in warm clouds is enjoying a revival, based on some positive indications from research in South Africa, Mexico, and elsewhere. The hygroscopic material most commonly used is salt. It is postulated that hygroscopic seeding causes the droplet size spectrum in clouds to become more maritime (bigger drops) and less continental, stimulating rainfall through coalescence.
From March 1967 until July 1972, the U.S. military's Operation Popeye cloud seeded silver iodide to extend the monsoon season over North Vietnam, specifically the Ho Chi Minh Trail. The operation resulted in the targeted areas seeing an extension of the monsoon period an average of 30 to 45 days.[2] The 54th Weather Reconnaissance Squadron carried out the operation to "make mud, not war". [3]
In 1969 at the Woodstock Festival, various people claimed to have witnessed clouds being seeded by the U.S. military. This was said to be the cause of the rain which lasted throughout most of the festival.
One private organization which offered, during the 1970s, to conduct weather modification (cloud seeding from the ground using silver iodide flares) was Irving P. Krick and Associates of Palm Springs, California. They were contracted by the Oklahoma State University in 1972 to conduct such a seeding project to increase warm cloud rainfall in the Lake Carl Blackwell watershed. That lake was, at that time (1972-73), the primary water supply for Stillwater, Oklahoma and was dangerously low. The project did not operate for a long enough time to show statistically any change from natural variations. However, at the same time, seeding operations have been ongoing in California since 1948.
An attempt by the United States military to modify hurricanes in the Atlantic basin using cloud seeding in the 1960s was called Project Stormfury. Only a few hurricanes were tested with cloud seeding because of the strict rules that were set by the scientists of the project. It was unclear whether the project was successful; hurricanes appeared to change in structure slightly, but only temporarily. The fear that cloud seeding could potentially change the course or power of hurricanes and negatively affect people in the storm's path stopped the project.
Two Federal agencies have supported various weather modification research projects, which began in the early 1960s: The United States Bureau of Reclamation (Reclamation; Department of the Interior) and the National Oceanic and Atmospheric Administration (NOAA; Department of Commerce). Reclamation sponsored several cloud seeding research projects under the umbrella of Project Skywater from 1964 to 1988, and NOAA conducted the Atmospheric Modification Program from 1979 to 1993. The sponsored projects were carried out in several states and two countries (Thailand and Morocco), studying both winter and summer cloud seeding. More recently, Reclamation sponsored a small cooperative research program with six Western states called the Weather Damage Modification Program [4], from 2002–2006.
Funding for research in the United States has declined in the last two decades. The Bureau of Reclamation sponsored a six-state research program from 2002–2006, however, called the Weather Damage Modification Program. A 2003 study by the United States National Academy of Sciences urges a national research program to clear up remaining questions about weather modification's efficacy and practice.
In Australia, CSIRO conducted major trials between 1947 and the early 1960s:
Only the trial conducted in the Snowy Mountains produced statistically significant rainfall increases over the entire experiment.
An Austrian study[10] to use silver iodine seeding for hail prevention ran during 1981–2000, and the technique is still actively deployed there.[11]
The largest cloud seeding system in the world is that of the People's Republic of China, which believes that it increases the amount of rain over several increasingly arid regions, including its capital city, Beijing, by firing silver iodide rockets into the sky where rain is desired. There is even political strife caused by neighboring regions which accuse each other of "stealing rain" using cloud seeding. About 24 countries currently practice weather modification operationally. China used cloud seeding in Beijing just before the 2008 Olympic Games in order to clear the air of pollution, but there are disputes regarding the Chinese claims. In February 2009, China also blasted iodide sticks over Beijing to artificially induce snowfall after four months of drought, and blasted iodide sticks over other areas of northern China to increase snowfall. The snowfall in Beijing, which rarely experiences snow, lasted for approximately three days and led to the closure of 12 main roads around Beijing.[12]
In the United States, cloud seeding is used to increase precipitation in areas experiencing drought, to reduce the size of hailstones that form in thunderstorms, and to reduce the amount of fog in and around airports. Cloud seeding is also occasionally used by major ski resorts to induce snowfall. Eleven western states and one Canadian province (Alberta) have ongoing weather modification operational programs [5]. In January 2006, an $8.8 million cloud seeding project began in Wyoming to examine the effects of cloud seeding on snowfall over Wyoming's Medicine Bow, Sierra Madre, and Wind River mountain ranges. [6]
A number of commercial companies, such as Aero Systems Incorporated [7], Atmospherics Incorporated [8], North American Weather Consultants [9], Weather Modification Incorporated [10], Weather Enhancement Technologies International [11], Seeding Operations and Atmospheric Research (SOAR) [12], offer weather modification services centered on cloud seeding. The USAF proposed its use on the battlefield in 1996, although the U.S. signed an international treaty in 1978 banning the use of weather modification for hostile purposes.
In Australia, CSIRO’s activities in Tasmania in the 1960s were successful[citation needed]. Seeding over the Hydro-Electricity Commission catchment area on the Central Plateau achieved rainfall increases as high as 30% in autumn. The Tasmanian experiments were so successful that the Commission has regularly undertaken seeding ever since in mountainous parts of the State.
Russian military pilots seeded clouds over Belarus after the Chernobyl disaster to remove radioactive particles from clouds heading toward Moscow.[13]
Beginning in Winter 2004, Snowy Hydro Limited is conducting a six-year research project of winter cloud seeding to assess the feasibility of increasing snow precipitation in the Snowy Mountains in Australia. The NSW Natural Resources Commission, responsible for supervising the cloud seeding operations, believes that the trial may have difficulty establishing statistically whether cloud seeding operations are increasing snowfall. This project was discussed at a summit in Narrabri, NSW on 1 December 2006. The summit met with the intention of outlining a proposal for a 5 year trial, focussing on Northern NSW.
The various implications of such a widespread trial were discussed, drawing on the combined knowledge of several worldwide experts, including representatives from the Tasmanian Hydro Cloud Seeding Project however does not make reference to former cloud seeding experiments by the then Snowy Mountains Authority which rejected weather modification. The trial required changes to NSW environmental legislation in order to facilitate placement of the cloud seeding apparatus. The modern experiment is not supported for the Australian Alps.
At the July 2006 G8 Summit, President Putin commented that air force jets had been deployed to seed incoming clouds so they rained over Finland. Rain drenched the summit anyway.[14]
In Southeast Asia, open burning produces haze that pollutes the regional environment. Cloud-seeding has been used to improve the air quality by encouraging rainfall.
In December 2006, the Queensland government of Australia announced AUD$7.6 million in funding for "warm cloud" seeding research to be conducted jointly by the Australian Bureau of Meteorology and the United States National Center for Atmospheric Research.[15] Outcomes of the study are hoped to ease continuing drought conditions in the states South East region.
In Moscow, the Russian Airforce tried seeding clouds with bags of cement on Jun 17, 2008. One of the bags did not pulverize and went through the roof of a house.[16]
In India, Cloud seeding operations were conducted during the years 2003 and 2004 through U.S. based Weather Modification Inc. in state of Maharashtra [17]. In 2008, there are plans for 12 districts of state of Andhra Pradesh [18].
http://en.wikipedia.org/wiki/Cloud_Seeding
Weather warfare, Wikipedia LCD
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http://en.wikipedia.org/wiki/Weather_warfare
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This article is an orphan, as few or no other articles link to it. Please introduce links to this page from other articles related to it. (December 2008) |
Weather warfare is the use of weather modification techniques for military purposes.
The Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques (Geneva: 18 May 1977, Entered into force: 5 October 1978) prohibits "widespread, long-lasting or severe effects as the means of destruction, damage or injury" [1]. However it has been argued that this permits "local, non-permanent changes" [2].
Prior to the Geneva Convention, the United States used weather warfare in the Vietnam War. Under the auspices of the Air Weather Service, the United States used cloud seeding over the Ho Chi Minh Trail, increasing rainfall by an estimated thirty percent during 1967 and 1968. It was hoped that the increased rainfall would reduce the rate of infiltration down the trail.[citation needed]
With much less success, the United States also dropped salt on the airbase during the siege of Khe Sanh in an attempt to reduce the fog that hindered air operations.[citation needed]
According to a report produced for the United States Air Force written in 1996, weather modification technologies "do not currently exist. But as they are developed, the importance of their potential applications rises rapidly." Such emerging technologies are described as "a force multiplier with tremendous power that could be exploited across the full spectrum of war-fighting environments." [1]
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This climatology/meteorology-related article is a stub. You can help Wikipedia by expanding it. |
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This article related to a weapon is a stub. You can help Wikipedia by expanding it. |
http://en.wikipedia.org/wiki/Weather_warfare
Weather control, Wikipedia LCD
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http://en.wikipedia.org/wiki/Weather_modification
Weather control is the act of manipulating or altering certain aspects of the environment to produce desirable changes in weather.
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Some American Indians had rituals which they believed could induce rain. The Finnish people, on the other hand, were believed by others to be able to control weather. As a result, Vikings refused to take Finns on their oceangoing raids. Remnants of this superstition lasted into the twentieth century, with some ship crews being reluctant to accept Finnish sailors. The early modern era saw people observe that during battles the firing of cannons and other firearms often initiated precipitation. Magical and religious practices to control the weather are attested in a variety of cultures. In Greek mythology, Iphigenia was sacrificed as a human sacrifice to appease the wrath of the goddess Artemis, who had caused the Achaean fleet to be becalmed at Aulis at the beginning of the Trojan War. In Homer's Odyssey, Aeolus, keeper of the winds, bestowed Odysseus and his crew with a gift of the four winds in a bag. However, the sailors open the bag while Odysseus slept, looking for booty, and as a result are blown off course by the resulting gale.[1] In ancient Rome, the lapis manalis was a sacred stone kept outside the walls of Rome in a temple of Mars. When Rome suffered from drought, the stone was dragged into the city.[2] The Berwick witches of Scotland were found guilty of using black magic to summon storms to murder King James VI of Scotland by seeking to sink the ship upon which he travelled.[3] Scandinavian witches allegedly claimed to sell the wind in bags or magically confined into wooden staves; they sold the bags to seamen who could release them when becalmed.[4] In various towns of Navarre, prayers petitioned Saint Peter to grant rain in time of drought. If the rain was not forthcoming, the statue of St Peter was removed from the church and tossed into a river.[5] In the Middle Ages, Abbas Ibn Firnas invented an artificial weather simulation room in which spectators saw and were astonished by stars, clouds, artificial thunder, and lightning which were produced by mechanisms hidden in his basement laboratory.[6]
Perhaps the first example of practical weather control is the lightning rod. In the 1950s, computer scientist John von Neumann, an early theorizer on weather control, surmised that if Earth were to enter another Ice Age, a preventative solution would be to dump dirt (or spray soot from cropdusting planes) on the surface of the planet's glaciers. He noted that this would significantly change their reflectivity (albedo), and thus increase the solar energy retained by the planet. Such a strategy would require repeated applications, as storms would cover some portion of the soot with new snow until their frequency and range abated. The theoretical efficacy of von Neumann's proposal remains to be examined. Wilhelm Reich performed cloudbusting experiments in the 1950s to 1960s, the results of which are controversial and not widely accepted by mainstream science. Dr Walter Russell wrote of weather control in Atomic Suicide 1956. Jack Toyer in the 1970s built a rainmaker on Palmers Island near Grafton using a solar mirror, electromagnetic static charge, and infra red frequencies of light to induce weather in regional areas within Australia. His work was continued by his successor, Peter Stevens.
Cloud seeding is a common technique intended to trigger rain, but evidence on its effectiveness is mixed. Critics generally contend that claimed successes occur in conditions which were going to rain anyway. It is used in several different countries, including the United States, the People's Republic of China, and Russia. In the People's Republic of China there is a perceived dependency upon it in dry regions, which believe they are increasing annual rainfall by firing silver iodide rockets into the sky where rain is desired. In the United States, dry ice or silver iodide may be injected into a cloud by aircraft, or from the ground, in an attempt to increase rainfall; some companies are dedicated to this form of weather modification.
Project Stormfury was an attempt to weaken tropical cyclones by flying aircraft into storms and seeding the eyewall with silver iodide. The project was run by the United States Government from 1962 to 1983. A similar project using soot was run in 1958, with inconclusive results.[7] Various methods have been proposed to reduce the harmful effects of hurricanes. Moshe Alamaro of the Massachusetts Institute of Technology[8] proposed using barges with upward-pointing jet engines to trigger smaller storms to disrupt the progress of an incoming hurricane; critics doubt the jets would be powerful enough to make any noticeable difference.[7]
Alexandre Chorin of the University of California at Berkeley proposed dropping large amounts of environmentally friendly oils on the sea surface to prevent droplet formation.[9] Experiments by Kerry Emanuel[10] of MIT in 2002 suggested that hurricane-force winds would disrupt the oil slick, making it ineffective.[11] Other scientists disputed the factual basis of the theoretical mechanism assumed by this approach.[12] The Florida company Dyn-O-Mat proposes the use of a product it has developed, called Dyn-O-Gel, to reduce the strength of hurricanes. The substance is a polymer in powder form which reportedly has the ability to absorb 1,500 times its own weight in water. The theory is that the polymer is dropped into clouds to remove their moisture and force the storm to use more energy to move the heavier water drops, thus helping to dissipate the storm. When the gel reaches the ocean surface, it is reportedly dissolved. The company has tested the substance on a thunderstorm, but there has not been any scientific consensus established as to its effectiveness.[13] Hail cannons are used by some farmers in an attempt to ward off hail, but there is no reliable scientific evidence to confirm or deny their effectiveness. Another new anti-hurricane technology [1] is a method for the reduction of tropical cyclones’ destructive force - pumping sea water into and diffusing it in the wind at the bottom of such tropical cyclone in its eyewall.
In the largest rain dispersal operation on record in China, and the first time that such technology was used in conjunction with the Olympics, the Beijing Municipal Meteorological Bureau fired a total of 1,104 rain dispersal rockets within an eight-hour period prior to and during the opening ceremonies of the Games of the XXIX Olympiad on August 8, 2008. The rockets were launched from twenty-one sites and may have prevented the ceremonies from receiving rainfall in the range of 25 to 100 millimeters of rain.
With a rainy weather forecast for the Olympic night, and 90% humidity, the attempt "successfully intercepted a stretch of rain belt from moving towards the stadium..." said Guo Hu, head of the Beijing Municipal Meteorological Bureau. "..."Under such a weather condition, a small bubble in the rain cloud would have triggered rainfall, let alone a lightning..." said Guo, according to Xinhua News' 2008 Olympics website. In the subsequent days that followed torrential rain nearly washed the games out.
The High-frequency Active Auroral Research Program (HAARP) is a congressionally initiated program jointly managed by the U.S. Air Force and U.S. Navy. The HAARP complex is situated within a 23-acre lot in a relatively isolated region near the town of Gakona. When the final phase of the project is completed in 1997, the military will have erected 180 towers, 72 feet in height, forming a "high-power, high frequency phased array radio transmitter" capable of beaming in the 2.5-10 megahertz frequency range, at more than 3 gigawatts of power (3 billion watts). http://www.haarp.alaska.edu/haarp/prpeis.html
HIPAS has several diverse experimental facilities: a 1-megawatt rf transmitter to produce ELF/VLF (Extremely Low Frequency and Very Low Frequency) electromagnetic (EM) generation by the absorption of radio frequency (rf) power in the arctic ionosphere including ion cyclotron excitation; a 100 kW rf plasma torch used in research on the destruction of hazardous waste; a 2.7 m liquid mirror telescope used with one of several lasers for ionospheric stimulation and measurement; an Incoherent Scatter Radar (a new project using 88 ft. diameter antenna at NOAA Gilmore Creek site 34 km SW of HIPAS as the receiving antenna with the transmitter at HIPAS). HIPAS is in the process of adding a very high power (terawatt) laser (recently obtained from LLNL) to perform laser breakdown experiments in the ionosphere. Two Diesel electric generators (1500 HP 4160 V, 3-phase, 1.2 MVA each) are used to power the experiments. There are a number of computers (PC's ) on site, and a high-speed data line to UAF is available. While these experiments are useful in measuring the properties of the ionosphere, they produce insufficient amounts of energy to modify it in any significant way. however hotspots can be created within the ionospehere where this radiation is focused, temperatures can be elevated by up to 1600`k causing expansion of the ionosphere and subsequent changes in pressure and temperature, which in turn lead to changes in the global meteorology.
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The examples and perspective in this article deal primarily with the United States and do not represent a worldwide view of the subject. Please improve this article or discuss the issue on the talk page. |
Weather control, as well as "weather tampering", for hostile or military purposes is expressly forbidden dating from at least December 10, 1976, when the "United Nations General Assembly Resolution 31/72, TIAS 9614 Convention[14] on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques" was adopted. The Convention was: Signed in Geneva May 18, 1977; Entered into force October 5, 1978; Ratification by U.S. President December 13, 1979; U.S. ratification deposited at New York January 17, 1980.[15]
Space Preservation Act Title: To preserve the cooperative, peaceful uses of space for the benefit of all humankind by permanently prohibiting the basing of weapons in space by the United States, and to require the President to take action to adopt and implement a world treaty banning space-based weapons. Sponsor: Rep Kucinich, Dennis J. http://thomas.loc.gov/cgi-bin/query/z?c107:H.R.2977.IH: The bill originally mentioned chemtrails and H.A.A.R.P.,but was modified and resubmitted as H.R.3616 and H.R.2440. H.R. 2977 Space Preservation Act of 2001 introduced October 2, 2001, 107th Congress, 1st Session. The bill was referred to committee and no futher action ensued. H.R. 3616 Space Preservation Act of 2002 introduced January 23, 2002, 107th Congress, 2d Session. The bill was referred to committee and no further action ensued. H.R. 2420 Space Preservation Act of 2005 introduced May 18, 2005, 109th Congress, 1st Session, with 34 co-sponsors (see accompanying list). The bill was referred to committee and no further action ensued. http://www.sourcewatch.org/index.php?title=Space_Preservation_Act
U.S. Senate Bill 517[16] and U.S. House Bill 2995[17] were two laws proposed in 2005 that would have allowed experimental weather modification by artificial methods, attempted to establish a Weather Modification Operations and Research Board, and implemented a national weather modification policy. Neither ever became law.
U.S. Senate Bill 1807 & U.S. House Bill 3445 Senate Bill 1807 and House Bill 3445, identical bills introduced July 17, 2007, propose to establish a Weather Mitigation Advisory and Research Board to federally fund weather modification research http://tlp.law.pitt.edu/SP_DiLorenzo_Weather%20Modification.htm sponsored by Kay Bailey Hutcheson and Mark Udall. http://www.govtrack.us/congress/bill.xpd?bill=s110-1807
Climatologist Ross Hoffman has simulated hurricane control based on selective heating and cooling (or prevention of evaporation).[18] Futurist John Smart has discussed the potential for weather control via space-based solar power networks. One proposal involves the gentle heating via microwave of portions of large hurricanes. Such chaotic systems may be susceptible to "side steering" with a few degrees of increased temperature/pressure at critical points. A sufficient network might keep the largest and most potentially damaging hurricanes from landfall, at the request of host nations. Blizzards, monsoons, and other extreme weather are also potential candidates for space-based amelioration.[citations needed] If large-scale weather control were to become feasible, potential implications may include:
For the 2008 Olympics, China had 30 airplanes, 4,000 rocket launchers, and 7,000 anti-aircraft guns to stop rain. Each system would shoot various chemicals into any threatening clouds to shrink rain drops before they reach the stadium.[19]
In popular culture, weather control technology can be encountered in the realms of public speculation, science fiction, and fantasy. The concept of weather control is often portrayed as a part of terraforming.
Conspiracy theorists have suggested that certain governments use or seek to use weather control as a weapon (eg via HAARP and/or chemtrails), but such allegations have not been proven. At a counterterrorism conference in 1997, United States Secretary of Defense William Cohen referred to the writings of futurist Alvin Toffler, specifically regarding concerns about "eco-terrorism" and intentionally caused natural disasters.[21]
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http://en.wikipedia.org/wiki/Weather_modification
Project Stormfury, Weather control, ... LCD
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Project Stormfury was an attempt to weaken tropical cyclones by flying aircraft into them and seeding with silver iodide. The project was run by the United States Government from 1962 to 1983.
http://en.wikipedia.org/wiki/Project_Stormfury
The hypothesis was that the silver iodide would cause supercooled water in the storm to freeze, disrupting the inner structure of the hurricane. This led to the seeding of several Atlantic hurricanes. However, it was later shown that this hypothesis was incorrect. In reality, it was determined most hurricanes do not contain enough supercooled water for cloud seeding to be effective. Additionally, researchers found that unseeded hurricanes often undergo the same structural changes that were expected from seeded hurricanes. This finding called Stormfury's successes into question, as the changes reported now had a natural explanation.
The last experimental flight was flown in 1971, due to a lack of candidate storms and a changeover in NOAA's fleet. More than a decade after the last modification experiment, Project Stormfury was officially canceled. Although a failure in its goal of reducing the destructiveness of hurricanes, Project Stormfury was not without merit. The observational data and storm lifecycle research generated by Stormfury helped improve meteorologists' ability to forecast the movement and intensity of future hurricanes.
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Cloud seeding was first attempted by Vincent Schaefer and Irving Langmuir. After witnessing the artificial creation of ice crystals, Langmuir became an enthusiastic proponent of weather modification.[1] Schaefer found that when he dumped crushed dry ice into a cloud, precipitation in the form of snow resulted.[2]
With regard to hurricanes, it was hypothesized that by seeding the area around the eyewall with silver iodide, latent heat would be released. This would promote the formation of a new eyewall. As this new eyewall was larger than the old eyewall, the winds of the tropical cyclone would be weaker due to a reduced pressure gradient.[3] Even a small reduction in the speed of a hurricane's winds would be beneficial; as the damage potential of a hurricane increased as the square of the wind speed,[4] a slight lowering of wind speed would have a large reduction in destructiveness.[4]
Due to Langmuir's efforts, and the research of Schaefer at General Electric, the concept of using cloud seeding to weaken hurricanes gathered momentum. Indeed, Schaefer had caused a major snowstorm on December 20, 1946 by seeding a cloud.[2] This caused GE to drop out for legal reasons. Schaefer and Langmuir assisted the U.S. military as advisors for Project Cirrus, the first large study of cloud physics and weather modification. Its most important goal was to try to weaken hurricanes.[5]
Project Cirrus was the first attempt to modify a hurricane. It was a collaboration of the General Electric Corporation, the US Army Signal Corps, the Office of Naval Research, and the US Air Force.[1] After several preparations, and initial skepticism by government scientists,[6] the first attempt to modify a hurricane began on October 13, 1947 on a hurricane that was heading west to east and out to sea.[5]
An airplane flew along the rainbands of the hurricane, and dropped nearly 80 pounds (36 kilograms) of crushed dry ice into the clouds.[1] The crew reported "Pronounced modification of the cloud deck seeded".[5] It is not known if that was due to the seeding. Next, the hurricane changed direction and made landfall near Savannah, Georgia. The public blamed the seeding, and Irving Langmuir claimed that the reversal had been caused by human intervention.[6] Cirrus was canceled,[5] and lawsuits were threatened. Only the fact that a system in the 1906 season had taken a similar path, as well as evidence showing that the storm had already begun to turn when seeding began, ended the litigation.[5] This disaster set back the cause of seeding hurricanes for eleven years.
The United States Weather Bureau's National Hurricane Research Project, founded in 1955, had as one of its objectives to investigate the scientific validity of hurricane modification methods. To this end, silver iodide dispensers were tested in Hurricane Daisy in August 1958. The flares were deployed outside of the hurricane eyewall,so this was an equipment test rather than a modification experiment. The equipment malfunctioned in all but one of the flights, and no conclusive data was acquired.[5]
The first seeding experiment since the Cirrus disaster was attempted on September 16, 1961, into Hurricane Esther by NHRP and the United States Navy aircraft. Eight cylinders of silver iodide were dropped into Esther's eyewall, and winds were recorded as weakening by 10 percent.[7] The next day, more seeding flights were made. This time, the silver iodide did not fall into the eyewall, and no reduction in windspeed was observed. These two results were interpreted as making the experiment a "success".[8]
The seedings into Hurricane Esther led to the establishment of Project Stormfury in 1962. Project Stormfury was a joint venture of the United States Department of Commerce and the United States Navy.[8]
There were several guidelines used in selecting which storms to seed. The hurricane had to have a less than 10 percent chance of approaching inhabited land within a day;[9] it had to be within range of the seeding aircraft; and it had to be a fairly intense storm with a well-formed eye.[7] The primary effect of these criteria was to make possible seeding targets extremely rare.[10]
No suitable storms formed in the 1962 season. Next year, Stormfury began by conducting experiments on cumulus clouds. From August 17 to 20 of that year, experiments were conducted in 11 clouds, of which six were seeded and five were controls. In five of the six seeded clouds, changes were observed that were consistent with the working hypothesis.[11]
On August 23, 1963, Hurricane Beulah was the site of the next seeding attempt. It had an indistinct eyewall. In addition, mistakes were made, as the seedings of silver iodide were dropped in the wrong places. As a consequence, nothing happened.[8] The next day, another attempt was made, and the seeders hit their targets. The eyewall was observed to fall apart and be replaced by another eyewall with a larger radius.[11] The sustained winds also fell by twenty percent.[11] All in all, the results of the experiments on Beulah were "encouraging but inconclusive."[12]
In the six years after Beulah, no seedings were conducted for several different reasons. In 1964, measurement and observation equipment was not ready to be used.[11] The year after that, all flights were used for additional experimentation in non-hurricane clouds.[11]
While out to sea in August of the 1965 Atlantic hurricane season, Stormfury meteorologists decided that Hurricane Betsy was a good candidate for seeding.[9] However, the storm immediately swung towards land, and on September 1, the planned flights were canceled. For some reason, the press was not notified that there were no seedings, and several newspapers reported that it had begun.[9] As Betsy passed close to the Bahamas and smashed into southern Florida, the public and Congress thought that seeding was underway and blamed Stormfury.[9] It took two months for Stormfury officials to convince Congress that Betsy was not seeded, and the project was allowed to continue.[9] A second candidate, Hurricane Elena stayed too far out to sea.[11]
After Betsy, two other hurricanes came close to being seeded. Hurricane Faith was considered a likely candidate, but it stayed out of range of the seeding planes.[11] That same year, recon flights were conducted into Hurricane Inez, but there were no seedings.[11] Both the 1967 and 1968 seasons were inactive. Because of that, there were no suitable seeding targets in either of those two seasons.[11]
There were no more near-seedings until 1969. In the interim, equipment was improved. What once was the primitive method of hand-dumping dry ice was replaced with rocket canisters loaded with silver iodide, and then gun-like devices mounted on the wings of the airplanes that fired silver iodide into the clouds. Observation equipment was improved.[9] Additional reconnaissance data was utilized to modify the working hypothesis. The new theory took cumulus towers outside the eyewall into account. According to the revised theory, by seeding the towers, latent heat would be released. This would trigger the start of new convection, which would then cause a new eyewall. Since the new eyewall was outside the original one, the first eyewall would be choked off of energy and fall apart. In addition, since the new eyewall was broader than the old one, the winds would be lower due to a less sharp pressure difference.[9]
Hurricane Debbie provided the best opportunity to test the underpinnings of Project Stormfury. In many ways it was the perfect storm for seeding: it did not threaten any land; it passed within range of seeding aircraft; and was intense with a distinct eye.[13] On August 18 and again on August 20, thirteen planes flew out to the storm to monitor and seed it. On the first day, windspeeds fell by 31%.[11] On the second day, windspeeds fell by 18%.[11] Both changes were consistent with Stormfury's working hypothesis. Indeed, the results were so encouraging that "a greatly expanded research program was planned."[14] Among other conclusions was the need for frequent seeding at close to hourly intervals.[15]
The 1970 and 1971 seasons provided no suitable seeding candidates.[11] Despite this, flights were conducted into Hurricane Ginger. Ginger was not a suitable storm for seeding, due to its diffuse, indistinct nature. The seeding had no effect. Ginger was the last seeding done by Project Stormfury.[11]
Atlantic hurricanes meeting all of the criteria were extremely rare, which made duplication of the "success" reached with Hurricane Debbie extremely difficult. Meanwhile, developments outside of meteorology hindered the cause of hurricane modification.
In the early 1970s, the Navy withdrew from the project.[16] Stormfury began to refocus its efforts on understanding, rather than modifying, tropical cyclones.[17] At the same time, the Project's aircraft were nearing the end of their operational lifetimes. At the cost of $30 million (year unknown)[16] two Lockheed P-3's were acquired. Due to the rarity of Atlantic hurricanes meeting the safety requirements, plans were made to move Stormfury to the Pacific and experiment on the large number of typhoons there.[10] This action required many of the same safety requirements as in the Atlantic, but had the advantage of a much higher number of potential subjects.[16]
The plan was to begin again in 1976, and seed typhoons by flying out of Guam. However, political issues blocked the plan. The People's Republic of China announced that it would not be happy if a seeded typhoon changed course and made landfall on its shores,[10] while Japan declared itself willing to put up with difficulties caused by typhoons because that country got more than half of its rainfall from tropical cyclones.[10]
Similar plans to operate Stormfury in the eastern north Pacific or in the Australian region also collapsed.[18]
Multiple eyewalls had been detected in very strong hurricanes before, including Typhoon Sarah[19] and Hurricane Donna,[20] although the double eyes were usually seen in very intense systems. Double eyewalls were also seen post-seeding in some of the seeded storms. At the time however, the only known times that rapid changes in eyewall diameter, other than during presumably successful seedings, was during rapid changes in intensity.[21] It remained controversial whether the seedings caused the secondary eyewalls or whether it was just a natural cycle.[22] Basically, if eyewall changes similar to those observed in seeded hurricanes were rare in unseeded tropical cyclones, it would provide powerful evidence that Project Stormfury was successful. Inversely, if such changes were common in unseeded systems, it would throw doubt on the very hypothesis and assumptions driving Project Stormfury.[23]
Data and observations began to accumulate that debunked Stormfury's working hypothesis. Beginning with Hurricanes Anita and David, flights by Hurricane Hunter aircraft encountered events similar to what happened in "successfully" seeded storms.[23] Anita itself had a weak example of a concentric eyewall cycle, and David a more dramatic one.[22] In August 1980, Hurricane Allen passed through the Atlantic, Caribbean, and Gulf of Mexico. It also underwent changes in the diameter of its eye and developed multiple eyewalls. All this was consistent with the behavior that would have been expected of Allen had it been seeded. Thus, what Stormfury was accomplishing by seeding was also happening on its own.[24]
Other observations in Hurricanes Anita, David, Frederic, and Allen[25] also discovered that tropical cyclones have very little supercooled water and a great deal of ice crystals.[26] The reason that tropical cyclones have little supercooled water is that the updrafts within such a system are too weak to prevent water from either falling as rain or freezing.[27] As cloud seeding needed supercooled water to function, the lack of supercooled water meant that seeding would have no effect.
Those observations called the basis for Project Stormfury into question. In the middle of 1983, Stormfury was finally canceled after the hypothesis guiding its efforts was debunked.[28]
In the sense of weakening hurricanes to reduce their destructiveness, Project Stormfury was a complete failure because it did not distinguish between natural phenomena in tropical cyclones and the impact of human intervention.[26] Millions of dollars had been spent trying to do the impossible. In the end, "[Project] STORMFURY had two fatal flaws: it was neither microphysically nor statistically feasible."[28]
In addition, Stormfury had been a primary generator of funding for the Hurricane Research Division. While the project was operational, the HRD's budget had been around $4 million (1975 USD; $16 million 2008 USD), with a staff of approximately 100 people.[29] Today, the HRD employs 30 people and has a budget of roughly $2.6 million each year.[30]
However, Project Stormfury had positive results as well. Knowledge gained during flights proved invaluable in debunking its hypotheses.[30] Other science resulted in a greater understanding of tropical cyclones. In addition, the Lockheed P-3's were perfectly suitable for gathering data on tropical cyclones, allowing improved forecasting of these monstrous storms.[30] Those planes are still used by the NOAA today.[31]
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