Engineering topics

Schubert, S.

Publications and source records attributed to Schubert, S..

23 records · Page 2

NASA NTRS1992

Monthly means of selected climate variables for 1985 - 1989

Meteorologists are accustomed to viewing instantaneous weather maps, since these contain the most relevant information for the task of producing short-range weather forecasts. Climatologists, on the other hand, tend to deal with long-term means, which portray the average climate. The recent emphasis on dynamical extended-range forecasting and, in particular measuring and predicting short term climate change makes it important that we become accustomed to looking at variations on monthly and longer time scales. A convenient toll for researchers to familiarize themselves with the variability which occurs in selected parameters on these time scales is provided. The format of the document was chosen to help facilitate the intercomparison of various parameters and highlight the year-to-year variability in monthly means.

Schubert, S.↗

NASA NTRS1990

An atlas of ECMWF analyses (1980-1987). Part 2: Second moment quantities

This document is an atlas based on European Center for Medium Range Weather Forecasts (ECMWF) initialized analyses for 1980-1987. Transports and variance are presented globally at 200 and 850 mb as well as zonally averaged for seasonal and annual averages. Selected fields are filtered to isolate the synoptic (2.5 days is less than periods is less than 6 days) and low frequency (10 days is less than periods is less than 90 days) regions of the spectrum. In addition, time series of the zonally and monthly averaged transports and variances are presented over the entire 8 year period.

Schubert, S.↗

NASA NTRS1990

An atlas of ECMWF analyses (1980-1987). Part 1: First moment quantities

This document is an atlas of the European Center for Medium Range Weather Forecasts (ECMWF) initialized analyses for 1980 to 1987. Various first moment quantities are presented for monthly, seasonal, and annual averages on a global cylindrical projection, as well as, cross section maps of zonal averages. Global maps of winds, temperature, stream function, and velocity potential are presented at 850 and 200 mb. In addition, global maps of the 300 mb height field (total and eddy), the 500 mb vertical velocity, the 850 mb moisture field, and sea level pressure are presented. The average seasonal cycle and anomalies during the 8 year period are presented for selected quantities.

Schubert, S.↗

NASA NTRS1985

Energy Sources of the Dominant Frequency Dependent 3-dimensional Atmospheric Modes

The energy sources and sinks associated with the zonally asymmetric winter mean flow are investigated as part of an on-going study of atmospheric variability. Distinctly different horizontal structures for the long, intermediate and short time scale atmospheric variations were noted. In previous observations, the 3-dimensional structure of the fluctuations is investigated and the relative roles of barotropic and baroclinic terms are assessed.

Schubert, S.↗

NASA NTRS1984

Predictability experiments using a low order empirically corrected dynamical model

It is generally accepted that day to day weather variations possess a finite range of predictability estimated to be approximately two weeks (e.g., Lorenz, 1965). However, considerable observational evidence points to the existence of a number of low frequency flow regimes which are potentially predictable beyond this limit. These include blocking events and teleconnection patterns such as those described in Wallace and Gutzler (1981). The problem of the predictability of such modes is addressed by employing a highly simplified dynamical model projected onto the modes of interest. These modes are computed from an empirical orthogonal function (EOF) analysis of 10-day averaged anomalies (deviations from the mean seasonal cycle) of the 500 mb stream function for the winters of 1967-76. The first three EOF's are associated with an index cycle and some of the teleconnection patterns. The fourth and ninth are related to North Pacific and North Atlantic blocking, respectively.

Schubert, S.↗