History of Doppler Weather Radar

The Doppler weather radar is a special kind of radar, that is used to locate precipitation and predict its future movements and intensity. The data obtained from such a radar is analyzed carefully, to ascertain the nature of storms and their potential to cause calamity. The Doppler Weather Radar was discovered by the National Severe Storms Laboratory (NSSL) in the United States.

The Doppler weather radar uses the principles of Doppler Effect for the purpose of studying the frequency of waves in the air, to ascertain the movement and direction of wind and to forecast weather. According to its theory, when the source of the waves approaches the observer (or radar), the frequency of the waves increases, while during recession, the frequency of the waves decreases. Thus, by studying the frequencies, the target location as well as the radial velocity of thunderstorms can be identified.

The history of weather radars dates back to the time of World War II. During this period, scientists who were working as operators of military radars, detected some sounds of returned echoes at the time of rainfall or snowfall. After the war, these scientists continued their research work in their respective countries, to formulate a method to utilize the echo patterns.

David Atlas from the United States, was one of the first among them who made a weather radar that could be usable. In Canada, J.S. Marshall, R.H. Douglas and their team made a major breakthrough by establishing a relation between the radiant energy of the radar with the rate of falling of rainwater on the ground. Scientists from the United Kingdom closely studied the characteristics of different types of clouds.

In the 50s and 60s, several weather services across the globe, developed reflectivity radars, that helped in measuring the location and magnitude of precipitation. In 1964, NSSL came into being, and started experimenting on the possible uses of the Doppler Effect on its radar.

In the 70s, weather radars became more standardized, with organized networks. Simultaneously, devices that could capture radar images were also created. There was an increase in the number of scanned angles, to obtain a distinct three-dimensional image of the precipitation. Thunderstorms during this time, could be examined only at Alberta Hail Project in Canada and NSSL in US.

In May 1973, Union City, Oklahoma, saw a massive devastation due to a tornado. The total life cycle of this mayhem was recorded by a Dopplerised radar developed by NSSL. Studies of it's life cycle revealed specific movements of clouds, before the tornado reached the ground. This revelation persuaded the National Weather Service, to accept Dopplerised radar as an important tool for weather forecasting.

The period between 1980 to 2000, saw the developed countries depending on radar networks. In this period, US, Canada, and France switched over from conventional radars to Doppler weather radars. The biggest advantage of the Doppler radar is that besides tracking the position and intensity, it also has the ability to track the relative velocity of the particles in air. The early 2000s saw many advances in the field of computer technology, that can detect the bad signs of weather much more easily.

Further for better evaluation of the data provided by radars are on. They can make the predictions even more precise, by targeting locations of thunderstorms as well as their radial velocity. As a result, it will be possible to save many lives from the mayhem following a thunderstorm.