Search Results

You are looking at 1 - 10 of 16 items for

  • Author or Editor: Robert G. Quayle x
  • All content x
Clear All Modify Search
Robert G. Quayle

Abstract

Wind speed records from twelve Ocean Weather Stations (OWS's) are compared to estimates from transient ships in the general vicinity of the on-station OWS position. Measured and estimated winds from transient ships within specified areas are also intercompared. The analysis is climatic rather than synoptic. The entire frequency distribution of wind speeds is computed from all available observations without regard to temporal simultaneity. The comparison is of long-term climatologies. The results show good agreement between OWS records and the estimated winds as reported in whole knots. The intercomparison between measurements and estimates from transient ships shows less satisfactory agreement for lower wind speeds, but fair agreement for higher values. An evaluation of a proposed new conversion scale for estimates shows some possible improvement at lower wind speeds, but unsatisfactory results in the higher ranges.

Full access
Robert G. Quayle and Robert G. Steadman

Abstract

Because of shortcomings in the current wind chill formulation, which did not consider the metabolic heat generation of the human body, a new formula is proposed for operational implementation. This formula, referred to as the Steadman wind chill, is based on peer-reviewed research including a heat generation and exchange model of an appropriately dressed person for a range of low temperatures and wind speeds. The Steadman wind chill produces more realistic wind chill equivalents than the current NWS formulation. It is easy to determine from tables (calculated by application of a quadratic fit in both U.S. and metric units) with values accurate to within 1°C.

Full access
Nathaniel B. Guttman and Robert G. Quayle

Abstract

The network of about 5600 cooperative stations in the United States provides the baseline temperature data upon which most climatologies are based. Since the data serve between 40 000 and 50 000 primary users each year, and untold secondary users, data review, a part of data quality control, is an important consideration. This paper reveals the magnitudes of data changes made during different levels of data review efforts. With a full-scale effort, only about one-half of one percent of all values are altered in some way. However, the magnitude of daily changes can be large, thereby affecting the computation of monthly statistics and affecting users' needs for daily data.

Full access
Hendry F. Diaz and Robert G. Quayle

Abstract

Time series of temperature and precipitation weighted by area and grouped by season for each of the 48 contiguous United States were analyzed. Within an 83-year period of record (1895–1977) three subperiods or climatic regimes are identified and the differences in their means and standard deviations plotted and analyzed. The statistical significance of the changes in the mean was calculated by using a two-tailed t test; for changes in the standard deviation, the F-ratio test was used.

The variation patterns suggest that an east-west mode for changes in both temperature and precipitation is dominant over the continental United States. Over the past 25 years the average temperature of the United States has decreased∼1°F (0.6°C) from the relatively warm interval of the 1920's to the middle 1950's. However, most of this cooling has occurred in the eastern United States. In winter, for example, the southeastern United States cooled ∼3°F (1.7°C), whereas the Far West actually recorded warmer mean temperatures amounting to ∼0.5°F (0.3°C). Increases in precipitation in the past 25 years have favored the eastern United States, as many areas of the western United States experienced diminished precipitation. No systematic relationship could be found between changes in mean temperature and precipitation and corresponding changes in their variance.

Among the potential effects of similar climatic fluctuations in the future are increased energy costs for heating and possible water shortages in the western states.

Full access
Nathaniel B. Guttman and Robert G. Quayle

The history of climatic divisions in the contiguous United States has been pieced together from fragmentary documentation. Each of the 48 contiguous states has been subdivided into climatic divisions. Divisional boundaries are now standardized, and a set of climatic variables for time-invariant divisional boundaries has been compiled for the period of record beginning in 1895. This paper documents the origins of climatic divisions, the computational methodology of an area-invariant divisional dataset maintained by the National Climatic Data Center, and the strengths and weaknesses of divisional data.

Full access
Henry F. Diaz and Robert G. Quayle

Abstract

Analysis of monthly-mean temperature and precipitation data for each of the 48 contiguous United States for the 1976–77 through 1978–79 winter seasons shows that the temperature and precipitation departures from the long-term means were extreme. The consecutive occurrence of such severely cold winters is unprecedented in the available 85-year record.

Variability of temperature and precipitation has increased in the past 5-year period, compared to previous pentads, mainly as a result of much greater frequency of extreme anomalies. An “extreme anomaly”is defined as a mean monthly or seasonal value exceeding two standard deviations from the long-term mean.

Statistical estimates of average return periods of winter mean temperatures equal to or lower than the actual values recorded for the past three seasons are close to the empirical values. However, the implausibly low probabilities for the occurrence of consecutive severe winters suggest that the development of large-scale anomalies in atmospheric circulation, which these low temperatures represent, may have a common dynamical forcing and that these forcing mechanisms possess time scales on the order of several years.

Full access
Henry F. Diaz and Robert G. Quayle

Abstract

The 1976–77 winter season is compared with earlier winters with respect to temperature and beating degree days. Comparisons are based on 1) station data; 2) composite indices derived from a combination of a few very long-term station records; 3) areally weighted state and regional temperature averages; and 4) population weighted beating degree days. Major conclusions are as follows:

1) January 1977 was possibly the coldest month experienced in the eastern half of the country in the past 200 years.

2) The 1976–77 winter was not a record-breaker for temperature for the contiguous 48 states as a whole, but set a new record for fuel demand because of the extreme cold in highly populated areas.

3) Relatively coarse networks of stations can be used for monitoring large-scale anomalous weather features; they allow use of continuous records covering more than 100 years for which dense networks do not exist. They also allow near-real-time assessment of anomalous weather events at a small fraction of the time and money needed to process data from a large number of stations.

Full access
Henry F. Diaz and Robert G. Quayle

Abstract

No abstract available.

Full access
Robert G. Quayle and Joe D. Elms

Abstract

Analysis of merchant ship observations reveals a sharp ridge of high wave frequency along the axis of the Benguela Current, nearly coincident with the major shipping lane in that area. The authors could find no other reference to this wave regime in the literature. The majority of these waves are found to be southerly or southeasterly seas reinforced by swells of similar origin and direction. The steady winds within the stable subsiding air on the eastern edge of the semi-permanent subtropical South Atlantic Oceanic high pressure area are channeled to the northwest by the South African land mass, forming the driving mechanism that generates the waves. The thermal low over the continent further reinforces this regime, as does coastal upwelling. Resultant sharp local anomalies in air temperature, cloud cover and other elements are also present.

Full access
Robert G. Quayle and Henry F. Diaz

Abstract

Site-specific total electric energy and heating oil consumption for individual residences show a very high correlation with National Weather Service airport temperature data when transformed to heating degree days. Correlations of regional total residential electrical consumption with airport heating degree days for about 40 000 dwelling units in an area of ∼6500 km2 over an 11-year period indicate that temperature is a dominant cause of short-term usage fluctuations. Cost increases since 1973 appear to have only temporarily slowed the growth rate in consumption. A time series of national population-weighted heating degree day totals for the period 1898–1978 provides a scenario of possible variations of weather-related residential energy consumption.

Full access