Weather Defined

Weather represents the atmospheric conditions experienced in the short term, encompassing factors such as temperature, precipitation, wind, air pressure, and humidity. It results from intricate atmospheric processes influenced by both land and ocean interactions. Variations in air pressure, moisture levels, and temperature arise from solar radiation, the Earth's rotation, and orientation, leading to extensive weather patterns.

The atmosphere operates as a chaotic system, where minor changes can yield significant consequences, making accurate weather prediction a challenge.

Section 1.1: Understanding Synoptic Weather Charts

Synoptic weather charts provide an overview of the atmospheric state based on observational data and models. Below, a historical synoptic chart from 1883 is juxtaposed with a modern chart from 2020.

The symbols depicted in these charts represent various atmospheric patterns. The black lines indicate isobars, which denote areas of constant air pressure, akin to elevation lines on a topographic map. The proximity of these lines indicates the steepness of the gradient, which correlates with wind speed.

In the Northern Hemisphere, winds flow clockwise around high-pressure areas and counterclockwise around low-pressure zones. Modern charts utilize red and blue lines to denote warm and cold fronts, respectively, while purple lines illustrate occluded fronts, where cold fronts overtake warm ones. Areas of significant instability are marked by thick black lines.

Section 1.2: The Advent of Weather Forecasting

In the 19th century, synoptic charts were meticulously drawn by hand. Meteorologists combined weather data from various locations, applying their knowledge to develop maps illustrating high and low-pressure systems. This led to the creation of the first weather forecasts, initially aimed at improving storm warnings. By 1861, the Met Office began issuing daily forecasts. An example from August 1, 1861, stated:

"The temperature in London [is] to be 62°F (16.7°C), clear with a south-westerly wind."

The advancement of weather forecasting relied on various scientific and technological innovations:

• Precise measurements of atmospheric variables
• The rise of meteorology as a scientific field
• Rapid communication over long distances
• Accurate and calibrated instruments

Historical weather knowledge, such as "Red sky at night, sailor's delight; red sky in the morning, sailor's warning," was passed down through generations. However, standardized observations necessitated well-calibrated instruments, including:

• The barometer, invented by Evangelista Torricelli in 1643, for air pressure measurement
• The thermometer, widely available in the 18th century for temperature readings
• The hygrometer for moisture assessment

The 19th century marked significant progress in standardizing meteorological measurements. Weather stations emerged in various countries, and naval officers documented conditions in their logbooks, aiding national meteorological offices in data collection.

An example of standardization is the Beaufort wind scale, developed by Francis Beaufort. This qualitative scale describes wind conditions, improving the accuracy of reports previously reliant on individual sailors' interpretations.

The Electric Telegraph and Global Meteorology

The introduction of the electric telegraph in the 1830s allowed for the rapid exchange of information, a significant improvement over previous, slower communication methods. The Meteorological Office in London collected weather reports from various stations across the British Isles and Europe, transmitted via telegraph.

This swift information relay reduced the time needed to issue forecasts, allowing for timely warnings that could prevent disasters.

The second video, "A Quick History of Weather Forecasting on Television," examines the evolution of weather reporting and forecasting in the media.

Meteorology became a global pursuit, with similar services emerging worldwide in the 19th century, including in the United States, Japan, Brazil, and India. Early forecasts, however, were often met with skepticism due to their inaccuracy. The first daily forecasts, published in newspapers during the 1860s, faced ridicule for their unreliability.

Despite the challenges, the ability to observe and document weather patterns, including storms, propelled the field of meteorology forward. In a time when maritime trade and travel were vital, storms posed significant risks. After the Royal Charter disaster, FitzRoy equipped numerous coastal fishing villages with barometers, empowering locals to monitor weather conditions.

FitzRoy's storm warnings were sometimes controversial; false alarms could financially burden fishing communities. Nonetheless, the broader understanding of storms and quicker warning times ultimately enhanced the safety of seafarers.

Summary

The mid-19th century heralded the onset of the industrial age, where advancements in technology, such as precise measuring instruments and the telegraph, facilitated nearly instantaneous weather observations over vast areas. Scientists began to elucidate the fundamental atmospheric processes, leading to the creation of the first synoptic weather charts and early forecasts that focused on extreme weather events.

Although these early forecasts lacked today's accuracy, the progress made by early meteorologists is noteworthy considering their limited resources.

Further Reading