scholarly journals Effect of Glaciers on Annual Run-Off, Johan Dahl Land, South Greenland

1988 ◽  
Vol 34 (117) ◽  
pp. 200-207 ◽  
Author(s):  
R. J. Braithwaite ◽  
Ole B. Olesen
Keyword(s):  
Statistical Model ◽  
Negative Correlation ◽  
Seasonal Variations ◽  
Data Sets ◽  
Weather Station ◽  
Moderate Amount ◽  
Run Off ◽  
Few Data

AbstractRun-off data for two basins in south Greenland, one of which contains glaciers, are compared with precipitation at a nearby weather station and with ablation measured in the glacier basin. Seasonal variations of run-off for the two basins are broadly similar while run-off from the glacier basin has smaller year-to-year variations. A simple statistical model shows that this is the result of a negative correlation between ablation and precipitation, which has the effect of reducing run-off variations in basins with a moderate amount of glacier cover although run-off variations may become large again for highly glacierized basins. The model also predicts an increasing run-off with ablation correlation and a decreasing run-off with precipitation correlation as the amount of glacier cover increases. Although there are still too few data sets from other parts of Greenland for final conclusions, there are indications that the present findings may be applicable to other Greenland basins.

scholarly journals Effect of Glaciers on Annual Run-Off, Johan Dahl Land, South Greenland

1988 ◽  
Vol 34 (117) ◽  
pp. 200-207 ◽  
Author(s):  
R. J. Braithwaite ◽  
Ole B. Olesen
Keyword(s):  
Statistical Model ◽  
Negative Correlation ◽  
Seasonal Variations ◽  
Data Sets ◽  
Weather Station ◽  
Moderate Amount ◽  
Run Off ◽  
Few Data

Abstract Run-off data for two basins in south Greenland, one of which contains glaciers, are compared with precipitation at a nearby weather station and with ablation measured in the glacier basin. Seasonal variations of run-off for the two basins are broadly similar while run-off from the glacier basin has smaller year-to-year variations. A simple statistical model shows that this is the result of a negative correlation between ablation and precipitation, which has the effect of reducing run-off variations in basins with a moderate amount of glacier cover although run-off variations may become large again for highly glacierized basins. The model also predicts an increasing run-off with ablation correlation and a decreasing run-off with precipitation correlation as the amount of glacier cover increases. Although there are still too few data sets from other parts of Greenland for final conclusions, there are indications that the present findings may be applicable to other Greenland basins.

scholarly journals Mapping Urban Environmental Performance with Emerging Data Sources: A Case of Urban Greenery and Traffic Noise in Sydney, Australia

2021 ◽  
Vol 13 (2) ◽  
pp. 605
Author(s):  
Zahra Nourmohammadi ◽  
Tanapon Lilasathapornkit ◽  
Mudabber Ashfaq ◽  
Ziyuan Gu ◽  
Meead Saberi
Keyword(s):  
Negative Correlation ◽  
Seasonal Variations ◽  
Environmental Performance ◽  
Traffic Noise ◽  
Time Dependent ◽  
Data Sources ◽  
Street Level ◽  
Urban Greenery ◽  
Key Aspects ◽  
Sydney Australia

Measuring urban environmental performance supports understanding and improving the livability and sustainability of a city. Creating a more livable and attractive environment facilitates a greater shift to active and greener transport modes. Two key aspects, among many others, that determine the environmental performance of an urban area are greenery and noise. This study aims to map street-level greenery and traffic noise using emerging data sources including crowd-sourced mobile phone-based data and street-level imagery data in Sydney, Australia. Results demonstrate the applicability of emerging data sources and the presented advanced techniques in capturing the seasonal variations in urban greenery and time-dependent nature of traffic noise. Results also confirm the presence of a negative correlation between urban greenery and traffic noise.

scholarly journals Sunset–sunrise difference in solar occultation ozone measurements (SAGE II, HALOE, and ACE–FTS) and its relationship to tidal vertical winds

2015 ◽  
Vol 15 (2) ◽  
pp. 829-843 ◽  
Author(s):  
T. Sakazaki ◽  
M. Shiotani ◽  
M. Suzuki ◽  
D. Kinnison ◽  
J. M. Zawodny ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Seasonal Variations ◽  
Climate Model ◽  
Transport Model ◽  
Stratospheric Aerosol ◽  
Data Sets ◽  
Chemical Transport Model ◽  
Latitude Range ◽  
Solar Occultation ◽  
Vertical Winds

Abstract. This paper contains a comprehensive investigation of the sunset–sunrise difference (SSD, i.e., the sunset-minus-sunrise value) of the ozone mixing ratio in the latitude range of 10° S–10° N. SSD values were determined from solar occultation measurements based on data obtained from the Stratospheric Aerosol and Gas Experiment (SAGE) II, the Halogen Occultation Experiment (HALOE), and the Atmospheric Chemistry Experiment–Fourier transform spectrometer (ACE–FTS). The SSD was negative at altitudes of 20–30 km (−0.1 ppmv at 25 km) and positive at 30–50 km (+0.2 ppmv at 40–45 km) for HALOE and ACE–FTS data. SAGE II data also showed a qualitatively similar result, although the SSD in the upper stratosphere was 2 times larger than those derived from the other data sets. On the basis of an analysis of data from the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) and a nudged chemical transport model (the specified dynamics version of the Whole Atmosphere Community Climate Model: SD–WACCM), we conclude that the SSD can be explained by diurnal variations in the ozone concentration, particularly those caused by vertical transport by the atmospheric tidal winds. All data sets showed significant seasonal variations in the SSD; the SSD in the upper stratosphere is greatest from December through February, while that in the lower stratosphere reaches a maximum twice: during the periods March–April and September–October. Based on an analysis of SD–WACCM results, we found that these seasonal variations follow those associated with the tidal vertical winds.

Seasonal variations in the composition and thermal properties of New Zealand milk fat: I. Fatty-acid composition

1973 ◽  
Vol 40 (2) ◽  
pp. 207-214 ◽  
Author(s):  
I. K. Gray
Keyword(s):  
Fatty Acid Composition ◽  
Thermal Properties ◽  
Fatty Acid ◽  
New Zealand ◽  
Acid Composition ◽  
Negative Correlation ◽  
Seasonal Variations ◽  
Milk Fat ◽  
Significant Negative Correlation ◽  
Weight Percentage

SummaryThe fatty-acid composition of 17 samples of New Zealand milk fat obtained throughout one dairy season is reported.The weight percentage of butyric (C4:0) acid was significantly correlated with that of caproic (C6:0) acid and that of caprylic (C8:0) acid. Percentages of C6:0and C8:0showed a highly significant correlation with each other and with weight percentages of capric (C10:0) and lauric (C12:0) acids.There was a highly significant negative correlation between palmitic (C16:0) and stearic (C18:0) acids and between C4:0and C16:0acids. Oleic (C18:1) acid showed significant negative correlations with C8:0, C10:0, C12:0, myristic (C14:0) and C16:0acids.

Experimenting on the past: a case study on changing analysability in English ly-adverbs

2017 ◽  
Vol 21 (2) ◽  
pp. 317-340 ◽  
Author(s):  
HENDRIK DE SMET ◽  
FREEK VAN DE VELDE
Keyword(s):  
Negative Correlation ◽  
Historical Data ◽  
Frequency Change ◽  
Data Sets ◽  
The Past ◽  
Analogous Composition ◽  
Using Data ◽  
Complex Words ◽  
Experimental Findings

While it is undoubtedly true that historical data do not lend themselves well to the reproduction of experimental findings, the availability of increasingly extensive data sets has brought some experimenting within practical reach. This means that certain predictions based on a combination of synchronic observations and uniformitarian thinking are now testable. Synchronic evidence shows a negative correlation between analysability in morphologically complex words and various measures of frequency. It is therefore expected that when the frequency of morphologically complex items changes, their analysability will change along with this. If analysability decreases, this should in turn be reflected in decreasing sensitivity to priming by items with analogous composition. The latter prediction is in principle testable on diachronic data, offering a way of verifying the diachronic effect of frequency change on analysability. In this spirit, the present article examines the relation between changing frequency and priming sensitivity, as a proxy to analysability. This is done for a sample of 250 English ly-adverbs, such as roughly, blindly, publicly, etc. over the period 1950–2005, using data from the Hansard Corpus. Some of the expected relations between frequency and analysability can be shown to hold, albeit with great variation across lexical items. At the same time, much of the variation in our measure of analysability cannot be accounted for by frequency or frequency change alone.

Wheat Prices and Trade in the Early Roman Empire

2012 ◽  
Author(s):  
Peter Temin
Keyword(s):  
Roman Empire ◽  
Roman Republic ◽  
Small Data ◽  
Data Sets ◽  
Data Points ◽  
Small Data Sets ◽  
Few Data ◽  
Late Roman

This chapter discusses how there is little of what economists call data on markets in Roman times, despite lots of information about prices and transactions. Data, as economists consider it, consist of a set of uniform prices that can be compared with each other. According to scholars, extensive markets existed in the late Roman Republic and early Roman Empire. Even though there is a lack of data, there are enough observations for the price of wheat, the most extensively traded commodity, to perform a test. The problem is that there is only a little bit of data by modern standards. Consequently, the chapter explains why statistics are useful in interpreting small data sets and how one deals with various problems that arise when there are only a few data points.

Mutation

1996 ◽  
Author(s):  
Thomas Bäck
Keyword(s):  
Genetic Algorithms ◽  
Base Pair ◽  
Full Range ◽  
Data Sets ◽  
Phenotypic Effect ◽  
Local Optima ◽  
Single Base ◽  
Biological Reality ◽  
Single Base Pair ◽  
Few Data

In section 1.1.3 it was clarified that a variety of different, more or less drastic changes of the genome are summarized under the term mutation by geneticists and evolutionary biologists. Several mutation events are within the bounds of possibility, ranging from single base pair changes to genomic mutations. The phenotypic effect of genotypic mutations, however, can hardly be predicted from knowledge about the genotypic change. In general, advantageous mutations have a relatively small effect on the phenotype, i.e., their expression does not deviate very much (in phenotype space) from the expression of the unmutated genotype ([Fut90], p. 85). More drastic phenotypic changes are usually lethal or become extinct due to a reduced capability of reproduction. The discussion, to which extent evolution based on phenotypic macro-mutations in the sense of “hopeful monsters” is important to facilitate the process of speciation, is still ongoing (such macromutations have been observed and classified for the fruitfly Drosophila melangonaster, see [Got89], p. 286). Actually, only a few data sets are available to assess the phylogenetic significance of macro-mutations completely, but small phenotypical effects of mutation are clearly observed to be predominant. This is the main argument justifying the use of normally distributed mutations with expectation zero in Evolutionary Programming and Evolution Strategies. It reflects the emphasis of both algorithms on modeling phenotypic rather than genotypic change. The model of mutation is quite different in Genetic Algorithms, where bit reversal events (see section 2.3.2) corresponding with single base pair mutations in biological reality implement a model of evolution on the basis of genotypic changes. As observed in nature, the mutation rate used in Genetic Algorithms is very small (cf. section 2.3.2). In contrast to the biological model, it is neither variable by external influences nor controlled (at least partially) by the genotype itself (cf. section 1.1.3). Holland defined the role of mutation in Genetic Algorithms to be a secondary one, of little importance in comparison to crossover (see [Hol75], p. 111): . . . Summing up: Mutation is a “background” operator, assuring that the crossover operator has a full range of alleles so that the adaptive plan is not trapped on local optima. . . .

scholarly journals Short-Period Oscillations of Earth Rotation

2000 ◽  
Vol 178 ◽  
pp. 533-544 ◽  
Author(s):  
B. Kołaczek ◽  
W. Kosek ◽  
H. Schuh
Keyword(s):  
Seasonal Variations ◽  
Earth Rotation ◽  
Polar Motion ◽  
Correlation Coefficients ◽  
Data Sets ◽  
Annual Variations ◽  
Geodetic Vlbi ◽  
Atmospheric Excitation ◽  
Short Period ◽  
Seasonal Oscillations

AbstractSub-seasonal variations and especially sub-seasonal oscillations with periods of about 120, 60, 50, 40 days in polar motion and of about 120, 60–90, and 50 days in LOD are presented. Variations of amplitudes of these sub-seasonal oscillations of polar motion are shown. Maxima of these amplitudes are of the order of 2–4 mas. These oscillations are elliptical ones. The correlation coefficients between geodetic and atmospheric excitation functions in this range of the spectrum are variable and have annual variations. Maxima of correlation coefficients are of the order of 0.6–0.8.Modern geodetic VLBI experiments provide very accurate results in polar motion and UT1–UTC with a temporal resolution of 3–7 minutes. Several irregular, quasi-periodic variations were found. In many UT1–UTC data sets, oscillations with periods around 8 hours and between 5 and 7 hours can be seen.

scholarly journals Impact Assessment for Building Energy Models Using Observed vs. Third-Party Weather Data Sets

2020 ◽  
Vol 12 (17) ◽  
pp. 6788 ◽  
Author(s):  
Eva Lucas Segarra ◽  
Germán Ramos Ruiz ◽  
Vicente Gutiérrez González ◽  
Antonis Peppas ◽  
Carlos Fernández Bandera
Keyword(s):  
Energy Demand ◽  
Meteorological Data ◽  
Building Energy ◽  
Third Party ◽  
Weather Data ◽  
Data Sets ◽  
Weather Station ◽  
Energy Models ◽  
The Impact ◽  
Energy Strategies

The use of building energy models (BEMs) is becoming increasingly widespread for assessing the suitability of energy strategies in building environments. The accuracy of the results depends not only on the fit of the energy model used, but also on the required external files, and the weather file is one of the most important. One of the sources for obtaining meteorological data for a certain period of time is through an on-site weather station; however, this is not always available due to the high costs and maintenance. This paper shows a methodology to analyze the impact on the simulation results when using an on-site weather station and the weather data calculated by a third-party provider with the purpose of studying if the data provided by the third-party can be used instead of the measured weather data. The methodology consists of three comparison analyses: weather data, energy demand, and indoor temperature. It is applied to four actual test sites located in three different locations. The energy study is analyzed at six different temporal resolutions in order to quantify how the variation in the energy demand increases as the time resolution decreases. The results showed differences up to 38% between annual and hourly time resolutions. Thanks to a sensitivity analysis, the influence of each weather parameter on the energy demand is studied, and which sensors are worth installing in an on-site weather station are determined. In these test sites, the wind speed and outdoor temperature were the most influential weather parameters.

Seasonal variations in heterotrophic bacterial populations in waters off Sydney

1964 ◽  
Vol 15 (1) ◽  
pp. 73
Author(s):  
AD Brown
Keyword(s):  
Negative Correlation ◽  
Seasonal Variations ◽  
Bacterial Population ◽  
Heterotrophic Bacteria ◽  
Bacterial Count ◽  
Early Summer ◽  
Total Bacterial Count ◽  
Bacterial Populations ◽  
Seawater Samples

Viable counts were made of heterotrophic bacteria in seawater samples taken from 0, 25, 50, 75, and 100 m at one station off Sydney over a period of 2 years. Populations, which fell largely within the range of 10-1000/ml, tended to be higher in spring and early summer than at other times. Some evidence was obtained of a negative correlation between bacterial population and chlorinity. There was no evidence of a correlation between bacterial populations and several other variables which were examined. A (presumed) species of Chromobacterium occurred intermittently at the lower depths with some suggestion of a correlation with season and total bacterial count.

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