Search Results
You are looking at 21 - 30 of 44 items for :
- Author or Editor: A. JAMES WAGNER x
- Article x
- Refine by Access: All Content x
The frequency of occurrence of frozen precipitation forms relative to the frequency of occurrence of non-frozen forms is determined as a function of geographical location and of the mean temperature (or thickness) of the layer from 1000 mb to 500 mb. The results are derived from the data for a large number of stations in the United States during two winter seasons. A map of the thickness values for equal probability of occurrence of frozen and non-frozen forms illustrates the effects of altitude and continentality.
It is found that the form of the precipitation can be specified with a confidence of 75 percent or more when the thickness value at a station is 100 feet or more from its “equal probability” value. Some refinements of the technique are discussed.
The frequency of occurrence of frozen precipitation forms relative to the frequency of occurrence of non-frozen forms is determined as a function of geographical location and of the mean temperature (or thickness) of the layer from 1000 mb to 500 mb. The results are derived from the data for a large number of stations in the United States during two winter seasons. A map of the thickness values for equal probability of occurrence of frozen and non-frozen forms illustrates the effects of altitude and continentality.
It is found that the form of the precipitation can be specified with a confidence of 75 percent or more when the thickness value at a station is 100 feet or more from its “equal probability” value. Some refinements of the technique are discussed.
THE WEATHER AND CIRCULATION OF JANUARY 1969
Continued Strong High-Latitude Blocking and Flood-Producing Rains in California
Abstract
No Abstract Available.
Abstract
No Abstract Available.
THE WEATHER AND CIRCULATION OF JANUARY 1970
Record Cold in the Eastern Third of the Nation and Record Rainfall in the Pacific Northwest
Abstract
No Abstract Available.
Abstract
No Abstract Available.
THE WEATHER AND CIRCULATION OF JUNE 1970
A Month With Sharp Temperature Variations, Warm in the Northwest and Cool in the Southeast
Abstract
No Abstract Available.
Abstract
No Abstract Available.
Abstract
The standardized departures of sea-level pressure from the normal over the Northern Hemisphere for each of the four seasons were examined by means of spectrum analysis. Emphasis was placed on interpreting the geographical distribution of relative spectral power at different periods, rather than the power distribution within the individual spectra.
The predominant characteristic of the data was trend, found to represent real meteorological effects and not spurious results of changes in station locations or times of observation. Particularly in subtropical latitudes where the trend was greatest, the data were characterized by large 1- and 2-year-lag autocorrelations and pronounced “red noise” spectra. Exceptionally large 2-year-lag autocorrelation coefficients over several extensive regions of the hemisphere were related to marked departures of the data series from a linear first-order Markov process in those areas.
Although not so strong in an absolute sense as the trend, several moderately strong quasi-periodicities were found that appeared to be related to specific geographical or climatological features. The seasonal sea-level pressure data from arid and semiarid regions in widely separated parts of the hemisphere displayed a rather strong peak of spectral power in the band centered near 21 yr.
Data from an extensive area of the northern Pacific Ocean showed a broad spectral peak in the range of 5 to 6 yr, particularly in winter and summer. A pronounced spectral peak in the vicinity of 2½ yr was observed in the data series for winter over the Gulf of Alaska, the Mediterranean, and to a lesser extent off the east coast of the United States. All these areas are characterized by frequent and often intense cyclogenesis during the colder months.
Although the large amount of trend in the data made if difficult to determine the significance of individual spectral peaks, the quasi-beinnial oscillation also appeared to be a real characteristic of the data. A moderate peak was observed in the spectrum of the data series for some subtropical and continental high-pressure areas, particularly in winter. A preponderance of the spectra at the individual Northern Hemisphere grid points displayed relative peaks in the range of 26 to 28 mo, most markedly for the winter data.
Abstract
The standardized departures of sea-level pressure from the normal over the Northern Hemisphere for each of the four seasons were examined by means of spectrum analysis. Emphasis was placed on interpreting the geographical distribution of relative spectral power at different periods, rather than the power distribution within the individual spectra.
The predominant characteristic of the data was trend, found to represent real meteorological effects and not spurious results of changes in station locations or times of observation. Particularly in subtropical latitudes where the trend was greatest, the data were characterized by large 1- and 2-year-lag autocorrelations and pronounced “red noise” spectra. Exceptionally large 2-year-lag autocorrelation coefficients over several extensive regions of the hemisphere were related to marked departures of the data series from a linear first-order Markov process in those areas.
Although not so strong in an absolute sense as the trend, several moderately strong quasi-periodicities were found that appeared to be related to specific geographical or climatological features. The seasonal sea-level pressure data from arid and semiarid regions in widely separated parts of the hemisphere displayed a rather strong peak of spectral power in the band centered near 21 yr.
Data from an extensive area of the northern Pacific Ocean showed a broad spectral peak in the range of 5 to 6 yr, particularly in winter and summer. A pronounced spectral peak in the vicinity of 2½ yr was observed in the data series for winter over the Gulf of Alaska, the Mediterranean, and to a lesser extent off the east coast of the United States. All these areas are characterized by frequent and often intense cyclogenesis during the colder months.
Although the large amount of trend in the data made if difficult to determine the significance of individual spectral peaks, the quasi-beinnial oscillation also appeared to be a real characteristic of the data. A moderate peak was observed in the spectrum of the data series for some subtropical and continental high-pressure areas, particularly in winter. A preponderance of the spectra at the individual Northern Hemisphere grid points displayed relative peaks in the range of 26 to 28 mo, most markedly for the winter data.
THE WEATHER AND CIRCULATION OF OCTOBER 1970
Marked Persistence From September
Abstract
No Abstract Available.
Abstract
No Abstract Available.
WEATHER AND CIRCULATION OF JULY 1971
A Midmonth Circulation Reversal Accompanied by Drought-Relieving Rains in Texas
Abstract
No Abstract Available.
Abstract
No Abstract Available.
WEATHER AND CIRCULATION OF FEBRUARY 1971
A Stormy Month With a Marked Mid-Month Reversal in the Temperature Regime
Abstract
No Abstract Available.
Abstract
No Abstract Available.
THE WEATHER AND CIRCULATION OF JUNE 1969
A Predominantly Cool and Wet Month
Abstract
No Abstract Available.
Abstract
No Abstract Available.
THE WEATHER AND CIRCULATION OF JUNE 1967
A Cool Month With Excessive Rainfall in the Plains
Abstract
No Abstract Available.
Abstract
No Abstract Available.
