The numerical forecasts made in 1950 using the Electronic Numerical Integrator and Computer (ENIAC) paved the way for the remarkable advances that have been made over the past half-century in weather prediction and climate modeling. We review the circumstances in which the forecasts were made, the nature of the ENIAC machine, and the roles of the people involved. The basis for the forecasts was...

Abstract In recent years, renewable energies have been covering an increasing part of the worldwide electrical power demand. The additional volatility introduced to power grids by weather dependent renewable energy sources, i.e., wind and solar, makes it necessary to improve the accuracy of energy forecasts, so that the underlying electrical grid can be operated in a cost efficient way. Governm...

Numerical weather predictionmodels have a number of parameters whose values are either estimated from empirical data or theoretical calculations. These values are usually then optimized according to some criterion (e.g., minimizing a cost function) in order to obtain superior prediction. To that end, it is useful to knowwhich parameters have an effect on a given forecast quantity, and which do ...

The purpose of this paper is to develop a general framework for the prediction of complex multiscale phenomena and to illustrate this framework through comparison to two examples of current interest to the authors. Prediction involves a two step process of inverse prediction to describe the system, given observations of its behavior, and forward prediction, to specify system behavior, given its...

In China, 260 million people migrate to cities to realize their urban dreams. Despite that these migrants play an important role in the rapid urbanization process, many of them fail to settle down and eventually leave the city. The integration process of migrants thus raises an important issue for scholars and policymakers. In this paper, we use Shanghai as an example to investigate migrants’ b...

Sub-synoptic scale troughs and cyclones which form on the cold-air side of the main polar front are often responsible for adverse weather. Some of the more vigorous systems contain convective rainbands that can produce locally severe weather, including thunderstorms, with strong wind gusts and small tornadoes. There has, however, been relatively little research into the mesoscale organisation o...

We present the linear analysis of recent time filters used in numerical weather prediction. We focus on the accuracy and the stability of the leapfrog scheme combined with the Robert–Asselin–Williams filter, the higher-order Robert–Asselin type time filter, the compositetendency Robert–Asselin–Williams filter and a more discriminating filter.

Acknowledgments