How did Weather Monitoring Develop

We have increasingly become accustomed to seeing the impact of major hurricanes and weather phenomena on communities. Fortunately, over the 20th and 21st centuries, weather monitoring technologies, such as radar, have allowed us to obtain much more warning before events occur. However, weather monitoring has had a long historical road, as past and modern societies have always had a desire to know what would happen to their crops, homes and livelihoods.

Early Development

By the 3rd millennium BCE, seasonality and its regularity was recorded. Early weather recording often related to astronomical observations, as seasonal changes and time keeping were seen as being related. Some of the earliest detailed records of meteorological data derive from ancient Mesopotamia from the 8th century BCE. During that time, a detailed record spanning some six hundred years seems to have been collected that described weather phenomena, often focusing on difficult or bad weather. While the texts often focus on omens, particularly what might happen after a weather phenomenon such as storms, the compiling of the data suggests a type of forecasting was intended by the compilation. In effect, the records may have been an attempt to correlate weather events with other events, including political, economic and other important matters. Early records from Mesopotamia also indicate how celestial objects often foreshadowed weather events. For instance, a halo around the moon portends rain and flooding.

In China, records often seemed neutral as to the types of weather data kept. By the 13th century BCE, the Chinese were attempting to record amount of rainfall, types of precipitation (sleet vs. rain) and an indication of temperature. The Chinese, similar to Mesopotamia, also saw their weather as being related with the whim of the gods or their moral or immoral behavior. Records also indicates understanding of the hydrologic cycle and how distant events such as rainfall in the mountains could influence flooding. The concept of Yin and Yang was related to weather, where a balance between hot and cold and other opposites in weather were necessary for society to be balance. In effect, this is early evidence of how weather began to also shape philosophy and concepts of spiritual as well as physical balance in life.

Aristotle has often been considered a pioneer in meteorology with his book Meteorlogica, with the title suggesting that our present English term deriving from the ancient Greek. Aristotle saw that weather was affected by the four bodies, namely fire, air, earth, water. Many of his views involved the supernatural, similar to Mesopotamia and China; however, he made some important observations. For instance, the rising of hot air and the descent of cold air. He also understood that the atmosphere was complex, consisting of multiple layers.

Later Development

In the Roman Period, at around 25-50 CE, Pomponius Mela, who was a geographer, formulates a more comprehensive understanding of climatic zones. This includes zones that are comparable to our division of regions into temperate, arctic, desert, and tropical zones. His writings also suggest that these zones were related to the latitude in which someone was in, as more northerly zones generally were colder and more southerly zones had tropical zones. However, within the northern and southern zones, comparable climatic zones could be found and these affect the weather noticeable in those regions.

Other Late Antiquity and early Medieval developments also occurred in India, a region that had developed a strong meteorological tradition already by around 3000 BCE. Varahamihira wrote at around 500 CE about the importance of early rains and it is clear, similar to Chinese knowledge, that rain did not just come from the sky but related to the sun and evaporation. There were also attempts to correlate revenue, or the wider economy, with rainfall, as the timing of the rains was seen as being critical to affecting the wider economy. The types of clouds were seen as being a strong indication of the types of rains one could expect.