Weather modification in North America has been taking place since at least the 1950s. Programs related to this field have been authorized by the governments of both the United States and Canada.
The Alberta Hail Project was a research project sponsored by the Alberta Research Council and Environment Canada to study hailstorm physics and dynamics in order to design and test means for suppressing hail. It ran from 1956 until 1985. The main instrument in this research was an S-band circularly polarized weather radar located at the Red Deer Industrial Airport in central Alberta, Canada.
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.
Weather modification via cloud seeding has a long history in perennially dry Southern California. [1] Santa Barbara County has been cloud seeding with both ground-based machines and dedicated cloud-seeding airplanes since the 1980s. [1] In 2016, Los Angeles County rebooted its cloud seeding program (with ground-based machines) for the first time after 2002. [1]
Alberta is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Territories (NWT) to the north, and the U.S. state of Montana to the south. It is one of the only two landlocked provinces in Canada. The eastern part of the province is occupied by the Great Plains, while the western part borders the Rocky Mountains. The province has a predominantly continental climate but experiences quick temperature changes due to air aridity. Seasonal temperature swings are less pronounced in western Alberta due to occasional Chinook winds.
Hail is a form of solid precipitation. It is distinct from ice pellets, though the two are often confused. It consists of balls or irregular lumps of ice, each of which is called a hailstone. Ice pellets generally fall in cold weather, while hail growth is greatly inhibited during low surface temperatures.
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern. Tornadoes come in many shapes and sizes, and they are often visible in the form of a condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than 180 kilometers per hour, are about 80 meters across, and travel several kilometers before dissipating. The most extreme tornadoes can attain wind speeds of more than 480 kilometers per hour (300 mph), are more than 3 kilometers (2 mi) in diameter, and stay on the ground for more than 100 km.
Weather forecasting is the application of science and technology to predict the conditions of the atmosphere for a given location and time. People have attempted to predict the weather informally for millennia and formally since the 19th century.
Weather modification is the act of intentionally manipulating or altering the weather. The most common form of weather modification is cloud seeding, which increases rain or snow, usually for the purpose of increasing the local water supply. Weather modification can also have the goal of preventing damaging weather, such as hail or hurricanes, from occurring; or of provoking damaging weather against the enemy, as a tactic of military or economic warfare like Operation Popeye, where clouds were seeded to prolong the monsoon in Vietnam. Weather modification in warfare has been banned by the United Nations under the Environmental Modification Convention.
Environment and Climate Change Canada, is the department of the Government of Canada responsible for coordinating environmental policies and programs, as well as preserving and enhancing the natural environment and renewable resources. It is also colloquially known by its former name, Environment Canada.
A tornado warning is a severe weather warning product of the National Weather Service that is issued by regional offices of weather forecasting agencies throughout the world to alert the public when a tornado has been reported or indicated by weather radar within the parent severe thunderstorm. It can be issued after a tornado, funnel cloud and rotation in the clouds has been witnessed by the public, storm chasers, emergency management or law enforcement, and indicates that residents in the affected areas should take immediate safety precautions.
Cloud seeding is a type of weather modification that aims 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. Its effectiveness is debated; some studies have suggested that it is "difficult to show clearly that cloud seeding has a very large effect." The usual objective is to increase precipitation, either for its own sake or to prevent precipitation from occurring in days afterward.
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. The hypothesis was that the silver iodide would cause supercooled water in the storm to freeze, disrupting the inner structure of the hurricane, and this led to seeding several Atlantic hurricanes. However, it was later shown that this hypothesis was incorrect. It was determined that 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 chemtrail conspiracy theory is the erroneous belief that long-lasting condensation trails are "chemtrails" consisting of chemical or biological agents left in the sky by high-flying aircraft, sprayed for nefarious purposes undisclosed to the general public. Believers in this conspiracy theory say that while normal contrails dissipate relatively quickly, contrails that linger must contain additional substances. Those who subscribe to the theory speculate that the purpose of the chemical release may be solar radiation management, weather modification, psychological manipulation, human population control, biological or chemical warfare, or testing of biological or chemical agents on a population, and that the trails are causing respiratory illnesses and other health problems.
Rainmaking, also known as artificial precipitation, artificial rainfall and pluviculture, is the act of attempting to artificially induce or increase precipitation, usually to stave off drought or the wider global warming. According to the clouds' different physical properties, this can be done using airplanes or rockets to sow to the clouds with catalysts such as dry ice, silver iodide and salt powder, to make clouds rain or increase precipitation, to remove or mitigate farmland drought, to increase reservoir irrigation water or water supply capacity, to increase water levels for hydropower generation, or even to solve the global warming problem.
The Edmonton tornado of 1987, an event also known as Black Friday to Edmontonians, was a powerful and devastating tornado that ripped through the eastern parts of Edmonton, Alberta, Canada and parts of neighbouring Strathcona County on the afternoon of Friday, July 31, 1987. It was one of seven other tornadoes in central Alberta the same day.
Operation Sober Popeye was a military cloud-seeding project carried out by the U.S. Air Force during the Vietnam War in 1967–1972. The highly classified program attempted to extend the monsoon season over specific areas of the Ho Chi Minh Trail, in order to disrupt North Vietnamese military supplies by softening road surfaces and causing landslides.
The 1925 Miami tornado was an intense tornado that struck Dade County, Florida, on April 5, 1925. It remains the deadliest tornado to affect the South Florida county, and it is estimated to have been the most intense tornado to strike the Miami area. The tornado caused five deaths and produced damage totals that were estimated near $200–300,000 (1925 USD). 35 people were also hospitalized because of injuries. The tornado remains the only tornado to cause multiple fatalities in Dade County. While officially unrated, it is estimated that the tornado likely produced F3-level damage based on photographs taken after the passage of the supercell.
Irving P. Krick was an American meteorologist and inventor, the founding professor of Department of Meteorology at California Institute of Technology (1933–1948), one of the U.S. Air Force meteorologists who provided forecasts for the Normandy Landings in 1944, a controversial pioneer of long-term forecasting and cloud seeding, and "a brilliant American salesman" who in 1938 started the first private weather business in the United States.
Glacier Media is a Canadian business information and media products company. It provides news, market information and sector-specific data within North America and internationally.
Hailstorm Alley is a colloquial term referring to an area of south and central Alberta, Canada where hail storms are frequently produced. These storms frequently produce hail that is damaging to property. This area stretches from High River in southern Alberta, northward through Calgary, through Red Deer to Lacombe and then westward to Rocky Mountain House. It is known to be one of the worst areas in the world for damaging hail produced by thunderstorms. These are regarded as loose boundaries. While this area is common for damaging hailstorms, the reality is damaging hailstorms occur over much of central and southern Alberta every summer. The City of Calgary is regarded as the hailstorm capital of Canada.
The California drought manipulation conspiracy theory is a conspiracy theory that proposes that the 2011–2017 drought was a deliberate, man-made phenomenon, created by weather modification. It is largely promoted by a number of self-proclaimed "independent researchers" and "scientists", and by alternative news outlets. The theory has been dismissed by the scientific community and mainstream media as fringe science or pseudoscience.
The United Arab Emirates Research Program for Rain Enhancement Science (UAEREP) is a global research initiative offering a grant of US$5 million over a three-year period to be shared by up to five winning research projects in the field of rain enhancement.
Cloud seeding in the United Arab Emirates is a strategy used by the government to address water challenges in the country. Cloud seeding is also referred to as man made precipitation and artificial rain making. The United Arab Emirates is one of the first countries in the Persian Gulf region to use cloud seeding technology. UAE scientists use cloud seeding technology to supplement the country's water insecurity, which stems from the extremely hot climate. They use weather radar to continuously monitor the atmosphere of the country. Forecasters and scientists have estimated that cloud seeding operations can enhance rainfall by as much as 30-35% percent in a clear atmosphere, and up to 10-15% in a more humid atmosphere. This practice has caused concerns regarding the impact on the environment because it is difficult to predict the long-term global implications.
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