How the history of weather forecasting went from reading clouds to supercomputers

A Royal Air Force mobile meteorological unit during World War II.(Imperial War Museums via Getty Images)

Humans have tried to predict the weather since ancient times.

Over tens of thousands of years, Indigenous Australians developed an intricate knowledge of seasonal changes in the weather. For example, the Jawoyn in northern Australia recognizes five distinct seasons: Jeyowk, Bangkarrang, Malapparr, Jungalk and Guran.

Around 650 BCE, there are records of the Babylonians attempting to predict short-term weather movements by observing the clouds and astrological signs.

Then around 340 BCE, Greek philosopher Aristotle wrote Meteorologica, a treatise where he discussed weather and climate. Some of his ideas were correct (observations about the Earth’s hydrologic cycle), but many others were not (earthquakes being caused by winds trapped in the earth).

From these times onwards, there’s evidence of many other civilizations trying to divine the weather, especially via “reading” the sky to work out the next day’s weather.

Richard Whitaker, a meteorologist who worked at Australia’s Bureau of Meteorology for 30 years, says this was often informally codified through weather sayings.

Technological developments

As the centuries ticked over, different instruments were invented that became vital in weather forecasting.

In the 16th and 17th centuries, several European scientists (including Italian Galileo Galilei) developed increasingly reliable thermometers. Also around this time, Italian Evangelista Torricelli invented the barometer, which could measure atmospheric pressure.

But Professor Kristine Harper, an earth sciences historian at the University of Copenhagen, says scientific weather forecasting only really started to develop in the 19th century.

“We see the first scientific weather forecasting in the 19th century … [People] were recording temperature and pressure, because that was basically all they had equipment for. [Then] there were attempts to systematize it … To see if they could figure out what the weather was going to be for the next day,” Professor Harper says.

In the early 19th century, British Royal Navy officer Sir Francis Beaufort developed the wind force scale to classify wind speeds. Then following a major shipwreck off the coast of Wales in 1859, Beaufort’s protégé Robert FitzRoy was the first to make daily, public weather predictions, which he called “forecasts.”

But meteorologist Mr. Whitaker says around this time, “one of the big moments [in the history of weather forecasting] was not really connected with the weather at all.”

He says the invention and development of the electric telegraph in the 1800s meant weather data and information could be gathered and shared quickly.

For the first time, humans could observe weather systems moving from one location to another in real-time.

Equations solved by supercomputers 

Weather forecasting today is a culmination of all of those scientific, mathematical and technological developments.

As Professor Nicholls explains, there are now “thousands of points across the atmosphere, across the globe” that humans are monitoring for weather purposes, “from the [Earth’s] surface to kilometres above the surface.”

At these points, information is recorded, including temperature, pressure, air density and the wind movement.

“We put all of that together and solve, basically, seven equations. We solve them all simultaneously across the world, at all these levels. And the only way we can do that is by massive supercomputers, which do it all at once,” Professor Nicholls says.

So do humans still have a role in the process? Professor Harper is clear: “Of course.”

“Because we’re still the ones that have to interpret the charts … The meteorologists get these charts, they look at them, they discuss what’s going on. And then they’re the ones that tap up the forecasts.”

And from assisting global transport networks and agricultural practices, to life and death situations like cyclones, to whether or not we take an umbrella to work, these forecasts impact our lives every day.

Source: ABC News