Weather forecasting

Weather forecasting is the scientific application of technology to predict atmospheric conditions.

It involves studying the atmosphere, land, and ocean to project changes at a specific time and place. This process is vital for protecting lives and property through timely warnings. It also supports the global economy by helping farmers and utility companies prepare for changes. For example, in 2009, the United States spent about $5.8 billion on weather forecasting. This investment produced benefits estimated to be six times that amount.

Modern forecasting relies on a complex mechanism called numerical weather prediction. This process starts by sampling the current state of the atmosphere at a specific moment. Scientists collect quantitative data from automated weather stations on land and at sea. They then use mathematical equations based on fluid dynamics and thermodynamics. These equations describe how air and water move and change temperature. Computer-based models solve these equations to estimate future atmospheric states. However, the atmosphere is chaotic, which makes perfect prediction difficult. Errors can arise from measuring initial conditions or from an incomplete understanding of certain processes.

To manage these complex calculations, meteorologists use different tools and methods. One important method is the use of ensembles. An ensemble involves running many different models to see where they agree. This helps scientists find a consensus and increase their confidence in a forecast. Another method is pattern recognition, where humans identify specific atmospheric setups. Humans are still required to select the best model for a specific situation. They must understand model performance and recognize specific model biases. This combination of computer power and human skill helps narrow the margin of error.

Humanity has attempted to predict the weather for thousands of years using different methods. In 650 BC, the Babylonians used astrology and cloud patterns to make guesses. Around 350 BC, Aristotle described weather patterns in his work, *Meteorologica*. At the same time, Chinese and Indian astronomers were also developing prediction methods. For centuries, people relied on weather lore and pattern recognition. They observed that a red sunset often meant fair weather the next day. While many of these observations were useful, many did not survive rigorous statistical testing.

The modern era of forecasting began with the invention of the electric telegraph in 1835. Before this, weather reports traveled slowly by land or sea at only 60 to 120 kilometers per day. The telegraph allowed reports to arrive almost instantaneously from upwind locations. Two key figures, Francis Beaufort and Robert FitzRoy, helped turn forecasting into a science. Beaufort developed the Wind Force Scale and weather notation coding. FitzRoy was appointed in 1854 to collect weather data at sea for mariners.

He also coined the term "weather forecast" and published the first daily forecasts in *The Times* in 1861.

In the 20th century, the field underwent a massive shift toward mathematical modeling. In 1922, Lewis Fry Richardson published a plan for numerical weather prediction. He proposed using fluid dynamics equations to predict atmospheric flow. He imagined thousands of people performing these calculations by hand in a large auditorium. While his vision was too large for humans, it laid the groundwork for computers. In 1955, practical numerical prediction began using programmable electronic computers. A team including Jule Charney, Philip Duncan Thompson, Larry Gates, Ragnar Fjørtoft, John von Neumann, and Klara Dan von Neumann achieved this.

Weather information has also changed how we receive news through various media. In 1911, the Met Office began sending marine forecasts via radio. The first public radio forecasts in the United States appeared in 1925. Television brought a new visual dimension to the field in 1936. The BBC experimentally broadcast the first televised weather forecasts that year.

Later, in the 1970s and 1980s, meteorologists like John Coleman began using satellite data and computer graphics. This evolution continues today with weather reports available on live streaming platforms like YouTube.