The History of Numerical Weather Prediction Part ll

This is part 2 of last weeks post.

John von Neumann, the developer of that first computer (called the ENIAC), recognized that the problem of weather forecasting was a natural for his computing machinery. In 1948, he assembled a group of theoretical meteorologists at the Institute of Advanced Study in Princeton, New Jersey. The group was headed by Jule Charney, who had done extensive work on developing a simplified, filtered system of equations for weather forecasting. His group constructed a successful mathematical model of the atmosphere and demonstrated the feasibility of numerical weather prediction.

The first one-day, nonlinear weather prediction was made in April, 1950. Its completion required the round-the-clock services of the modelers, and, because of several ENIAC breakdowns, more than 24 hours to execute. However, this first forecast was successful in proving to the meteorological community that numerical weather prediction was feasible.

By 1954, both modeling capability and computer power had advanced to a point where the possibility of real-time operational numerical weather prediction was under active consideration in Europe and the United States. On July 1, 1954, the Joint Numerical Weather Prediction Unit (JNWPU) was organized, staffed, and funded by the U.S. Weather Bureau, the U.S. Air Force, and the U.S. Navy. This new unit was given the mission to apply emerging computer technology to the operational production of weather forecasts.

Using a newly purchased IBM 701, by mid-1955, the JNWPU was issuing numerical weather predictions twice a day. These early forecasts offered no competition for the ones being produced manually. However, the operational environment in which the forecasts were produced provided the necessary impetus to rapidly identify modeling problems and implement practical solutions. By 1958, the forecasts being produced began to show steadily increasing and useful skill.
The evolution of numerical weather prediction throughout the latter part of the 20th century proceeded at a similar pace at many operational numerical weather prediction centers around the globe. The first numerical weather prediction models used in the United States ran on grids that covered the Northern Hemisphere. This restriction was based primarily on the amount of computer power as well as the amount of data available to initialize the model. However, a progression of more and more powerful computers procured by the National Weather Service throughout the 1960s and 1970s as well as increasing sources of data—particularly from weather satellites—allowed the expansion of both the domains and the number of models run.
Increases were also made in the number of vertical levels and the horizontal resolution of the models. A three-layer hemispheric model was introduced in 1962 and a six-layer primitive equation model appeared in 1966. Additional atmospheric layers allowed more accurate forecasts of winds and temperature, resulting in better prediction of storm motion.
The first regional system concentrating on North America, called the Limited Fine Mesh model, was implemented in 1971. The first global model became operational in 1974.

Next week I will post part lll if I have a internet connection.  That post will come from Cocoa Beach, FL on Saturday we are leaving on the Carnival Magic and will not have a internet connection but will have a post in the bin for Micheal to post if he will.

While there has been a lot of talk that this winter would be a “lot different” than the past two. While February and March  may still be much different than the last two years. But the next few weeks look very mild for much of the US

 

 

 

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