SOME days or years have had historical reverberations. The fall of the Bastille in 1789, for example, was an event after which the world would never be the same. And the launch of Sputnik I in 1957 also ushered in another era. Shakespeare had a good sense of the fatefulness of certain times, as he illustrates in King Henry's speech on Crispian's Day, before the English army took the field at Agincourt:
He that outlives this day, and comes safe home,
Will stand a tip-toe when this day is named.
And rouse him at the name of Crispian.
Then shall our names,
Familiar in the mouth as household words
Be in the flowing cups, fleshly remembered.
Meteorology has also had its days of destiny, and its crucial years in which the science made a quantum leap. The first such, perhaps, may have been 334 BC, when Aristotle wrote a book called Meteorologica, which became the standard textbook on the weather for 2,000 years.
The next milestone did not occur until Renaissance times, when philosophers began to experiment with novel ways of looking at the natural phenomena. The 16th and 17th centuries saw the invention of many of the meteorological instruments we know today: Leonardo da Vinci invented, the hygrometer and a primitive version of the anemometer around 1500; Galileo Galilei produced a thermometer in 1600; and Evangelista Torricelli unveiled the world's first barometer in 1643.
The accurate measurements made possible by these instruments allowed the evolution of new theories about the ways in which our atmosphere behaves, but any attempt to forecast the weather had to await the invention of the electric telegraph around 1840.
Fifteen years later it was being used to relay weather observations in what computer people nowadays call "real time", allowing useful weather forecasts and storm warnings to be produced.
Thereafter the science developed rather quickly. The beginning of this century saw the invention of radio, which augmented the exchange of weather information and also led, in the early 1930s, to the development of radiosonde for measuring temperatures in the upper atmosphere.
Weather radar, to pin-point fronts and thunderstorms had arrived by 1950, and the 1960s saw the launching of the first weather satellites, which not only helped the forecaster on the bench, but also added to the information available for use in the sophisticated mathematical models of the atmosphere then being developed.
And the highlight of the 1970s and 1980s was the arrival of the supercomputer, which has brought numerical weather prediction to a stage undreamed of only a decade or two ago.