The Influence of the MJO on the Intraseasonal Variability of Northern Hemisphere Spring Snow Depth

2015 ◽  
Vol 28 (18) ◽  
pp. 7250-7262 ◽  
Author(s):  
Bradford S. Barrett ◽  
Gina R. Henderson ◽  
Joshua S. Werling
Keyword(s):  
North America ◽  
Northern Hemisphere ◽  
Air Temperature ◽  
Snow Depth ◽  
Intraseasonal Variability ◽  
Rank Correlation ◽  
Surface Air Temperature ◽  
Correlation Coefficients ◽  
Strong Relationship ◽  
The Relationship

Abstract Intraseasonal variability in springtime Northern Hemisphere daily snow depth change (ΔSD) by phase of the MJO was explored in this study. Principal findings of the relationship between ΔSD and the MJO included the following: 1) Statistically significant regions of lagged ΔSD anomalies for multiple phases of the MJO were found in March, April, and May in both North America and Eurasia. 2) In each month, lagged ΔSD anomalies were physically supported by corresponding lagged anomalies of 500-hPa height (Z500) and surface air temperature (SAT). Spearman rank correlation coefficients indicated a moderate to strong relationship between both Z500 and ΔSD and SAT and ΔSD in both Eurasia and North America for phases 5 and 7 in March. In April, a moderately strong relationship between Z500 and ΔSD was found over Eurasia for phase 5, but the relationship between SAT and ΔSD was weak. In May, correlations between ΔSD and both Z500 and SAT over a hemisphere-wide latitude band from 60° to 75°N were close to −0.5 and −0.4, respectively. Given the strength of these statistical relationships, the following physical pathway is proposed for intraseasonal variability of spring snow depth changes: poleward-propagating Rossby waves in response to tropical MJO convection interact with Northern Hemisphere background flow, leading to anomalous troughing and ridging. These anomalous circulation centers then impact daily snow depth change via precipitation processes and anomalies in surface air temperature.

scholarly journals Unraveling the Teleconnection Mechanisms that Induce Wintertime Temperature Anomalies over the Northern Hemisphere Continents in Response to the MJO

2016 ◽  
Vol 73 (9) ◽  
pp. 3557-3571 ◽  
Author(s):  
Kyong-Hwan Seo ◽  
Hyun-Ju Lee ◽  
Dargan M. W. Frierson
Keyword(s):  
North America ◽  
Eastern Europe ◽  
Northern Hemisphere ◽  
Air Temperature ◽  
Surface Air Temperature ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Temperature Variations ◽  
Temperature Anomalies ◽  
Air Temperature Variations

Abstract Significant extratropical surface air temperature variations arise as a result of teleconnections induced by the Madden–Julian oscillation (MJO). The authors elucidate the detailed physical processes responsible for the development of temperature anomalies over Northern Hemisphere continents in response to MJO-induced heating using an intraseasonal perturbation thermodynamic equation and a wave activity tracing technique. A quantitative assessment demonstrates that surface air temperature variations are due to dynamical processes associated with a meridionally propagating Rossby wave train. Over East Asia, a local Hadley circulation causes adiabatic subsidence following MJO phase 3 to be a main driver for the warming. Meanwhile, for North America and eastern Europe, horizontal temperature advection by northerlies or southerlies is the key process for warming or cooling. A ray-tracing analysis illustrates that Rossby waves with zonal wavenumbers 2 and 3 influence the surface warming over North America and a faster wavenumber 4 affects surface temperature over eastern Europe. Although recent studies demonstrate the impacts of the Arctic Oscillation, Arctic sea ice melting, and Eurasian snow cover variations on extremely cold wintertime episodes over the NH extratropics, the weather and climate there are still considerably modulated through teleconnections induced by the tropical heat forcing. In addition, the authors show that the MJO is a real source of predictability for strong warm/cold events over these continents, suggesting a higher possibility of making a skillful forecast of temperature extremes with over 1 month of lead time.

scholarly journals A Preliminary Study on Dependence of Mercury Distribution on the Degree of Coalification in Ningwu Coalfield, Shanxi, China

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3119
Author(s):  
Yinjiao Su ◽  
Xuan Liu ◽  
Yang Teng ◽  
Kai Zhang
Keyword(s):  
Linear Correlation ◽  
Bituminous Coal ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Chemical Extraction ◽  
Mercury Distribution ◽  
Sequential Chemical Extraction ◽  
Average Proportion ◽  
Total Proportion ◽  
The Relationship

Mercury (Hg) is a toxic trace element emitted from coal conversion and utilization. Samples with different coal ranks and gangue from Ningwu Coalfield are selected and investigated in this study. For understanding dependence of mercury distribution characteristics on coalification degree, Pearson regression analysis coupled with Spearman rank correlation is employed to explore the relationship between mercury and sulfur, mercury and ash in coal, and sequential chemical extraction method is adopted to recognize the Hg speciation in the samples of coal and gangue. The measured results show that Hg is positively related to total sulfur content in coal and the affinity of Hg to different sulfur forms varies with the coalification degree. Organic sulfur has the biggest impact on Hg in peat, which becomes weak with increasing the coalification degree from lignite to bituminous coal. Sulfate sulfur is only related to Hg in peat or lignite as little content in coal. However, the Pearson linear correlation coefficients of Hg and pyritic sulfur are relatively high with 0.479 for lignite, 0.709 for sub-bituminous coal and 0.887 for bituminous coal. Hg is also related to ash content in coal, whose Pearson linear correlation coefficients are 0.504, 0.774 and 0.827 respectively, in lignite, sub-bituminous coal and bituminous coal. Furthermore, Hg distribution is directly depended on own speciation in coal. The total proportion of F2 + F3 + F4 is increased from 41.5% in peat to 87.4% in bituminous coal, but the average proportion of F5 is decreased from 56.8% in peat to 12.4% in bituminous coal. The above findings imply that both Hg and sulfur enrich in coal largely due to the migration from organic state to inorganic state with the increase of coalification degree in Ningwu Coalfield.

COMPARATIVE ANALYSIS OF SPECTRA OF THE 2000-YEAR NORTHERN HEMISPHERE AVERAGE SURFACE AIR TEMPERATURE RECONSTRUCTIONS

2021 ◽  
pp. 5-13
Author(s):  
N. M. DATSENKO ◽  
◽  
D. M. SONECHKIN ◽  
B. YANG ◽  
J.-J. LIU ◽  
...  
Keyword(s):  
High Resolution ◽  
Northern Hemisphere ◽  
Air Temperature ◽  
Wavelet Transforms ◽  
Spectral Composition ◽  
Low Frequency ◽  
Surface Air Temperature ◽  
Temporal Variations ◽  
Continuous Wavelet Transforms ◽  
Stable Estimation

The spectral composition of temporal variations in the Northern Hemisphere mean surface air temperature is estimated and compared in 2000-year paleoclimatic reconstructions. Continuous wavelet transforms of these reconstructions are used for the stable estimation of energy spectra. It is found that low-frequency parts of the spectra (the periods of temperature variations of more than 100 years) based on such high-resolution paleoclimatic indicators as tree rings, corals, etc., are similar to the spectrum of white noise, that is never observed in nature. This seems unrealistic. The famous reconstruction called “Hockey Stick” is among such unrealistic reconstructions. Reconstructions based not only on high-resolution but also on low-resolution indicators seem to be more realistic, since the low-frequency parts of their spectra have the pattern of red noise. They include the “Boomerang” reconstruction showing that some warm periods close to the present-day one were observed in the past.

scholarly journals AN EVALUATION OF THE INFLUENCE OF PUPILS’ EATING HABITS ON THEIR ACADEMIC PERFORMANCE IN THE CONTEMPORARY SCHOOL SYSTEM

2021 ◽  
pp. 44-57
Author(s):  
Bernadette Egede ◽  
Keyword(s):  
Academic Performance ◽  
Rural Areas ◽  
Eating Habits ◽  
Survey Design ◽  
Correlation Coefficients ◽  
Strong Relationship ◽  
School Feeding ◽  
Primary School Pupils ◽  
The Relationship

The nexus between academic performance, nutrition and eating habit is globally recognized to the extent that it has inspired various strategies such as ‘school feeding programmes’ in many nations including Nigeria. This correlational study was aimed to evaluate the relationship between the eating habits of primary school pupils and their academic performance, using a survey design. Fifty pupils in two intact classes from two schools in rural areas, formed the sample. Data was collected using interviewer-questionnaire, coupled with naturalistic observation, for the eating habits and their results from the term’s examination done within the same periodin the schools. The data was analyzed using SPSS – 23 to determine the correlation coefficients. The results suggest that there is strong relationship between pupils’ eating habits, in terms of frequency of feeding, quality of feeding pattern, and quality of breakfast and their academic performance. In addition, the pupils perceived that eating light breakfast enhances their attention span to learn unlike, skipping of breakfast and eating heavy breakfast. The results of this study provide empirical evidence which can be used to encourage parents in rural areas to provide adequate nutrition for their wards/children to enhance their performance in school as recommended in this paper.

scholarly journals Influence of ENSO on North American subseasonal surface air temperature variability

2021 ◽  
Vol 2 (2) ◽  
pp. 395-412
Author(s):  
Patrick Martineau ◽  
Hisashi Nakamura ◽  
Yu Kosaka
Keyword(s):  
North America ◽  
Air Temperature ◽  
North American ◽  
Surface Air Temperature ◽  
Tropical Pacific ◽  
La Niña ◽  
Western North America ◽  
The North ◽  
Subseasonal Variability ◽  
La Nina

Abstract. The wintertime influence of tropical Pacific sea surface temperature (SST) variability on subseasonal variability is revisited by identifying the dominant mode of covariability between 10–60 d band-pass-filtered surface air temperature (SAT) variability over the North American continent and winter-mean SST over the tropical Pacific. We find that the El Niño–Southern Oscillation (ENSO) explains a dominant fraction of the year-to-year changes in subseasonal SAT variability that are covarying with SST and thus likely more predictable. In agreement with previous studies, we find a tendency for La Niña conditions to enhance the subseasonal SAT variability over western North America. This modulation of subseasonal variability is achieved through interactions between subseasonal eddies and La Niña-related changes in the winter-mean circulation. Specifically, eastward-propagating quasi-stationary eddies over the North Pacific are more efficient in extracting energy from the mean flow through the baroclinic conversion during La Niña. Structural changes of these eddies are crucial to enhance the efficiency of the energy conversion via amplified downgradient heat fluxes that energize subseasonal eddy thermal anomalies. The enhanced likelihood of cold extremes over western North America is associated with both an increased subseasonal SAT variability and the cold winter-mean response to La Niña.

The relationship between body mass and rate of rewarming from hibernation and daily torpor in mammals

1990 ◽  
Vol 151 (1) ◽  
pp. 349-359 ◽  
Author(s):  
F. Geiser ◽  
R. V. Baudinette
Keyword(s):  
Metabolic Rate ◽  
Body Mass ◽  
Air Temperature ◽  
Basal Metabolic Rate ◽  
Strong Relationship ◽  
The Other ◽  
Daily Torpor ◽  
Pronounced Increase ◽  
The Relationship

1. Rewarming rate from torpor and body mass were inversely related in 86 mammals ranging in body mass between 2 and 8500 g. 2. Most of the mammalian taxa investigated showed a similar change of rewarming rate with body mass. Only the insectivores showed a more pronounced increase in rewarming with a decrease in body mass than did the other taxa. The rates of rewarming of marsupials were similar to those of placentals. 3. At low air temperature (Ta), the rate of rewarming of marsupials was not related to body mass, although a strong relationship between the two variables was observed in the same species at high Ta. 4. The slopes relating rewarming rates and body mass of the mammalian groups and taxa analysed here were similar to those obtained earlier for mass-specific basal metabolic rate (BMR) and body mass in mammals, suggesting that the rate of rewarming and BMR are physiologically linked.

Winter surface air temperature prediction over Japan using artificial neural networks

2021 ◽  
Author(s):  
J. V. Ratnam ◽  
Masami Nonaka ◽  
Swadhin K. Behera
Keyword(s):  
Neural Networks ◽  
Artificial Neural Networks ◽  
Air Temperature ◽  
Surface Air Temperature ◽  
Correlation Coefficients ◽  
Ann Model ◽  
Anomaly Correlation ◽  
The North ◽  
Skill Scores ◽  
Artificial Neural

AbstractThe machine learning technique, namely Artificial Neural Networks (ANN), is used to predict the surface air temperature (SAT) anomalies over Japan in the winter months of December, January and February for the period 1949/50 to 2019/20. The predictions are made for the four regions Hokkaido, North, Central and West of Japan. The inputs to the ANN model are derived from the anomaly correlation coefficients among the SAT anomalies over the regions of Japan and the global SAT and sea surface temperature anomalies. The results are validated using anomaly correlation coefficient (ACC) skill scores with the observation. It is found that the ANN predictions over Hokkaido have higher ACC skill scores compared to the ACC scores over the other three regions. The ANN predicted SAT anomalies are compared with that of ensemble mean of 8 of the North American Multi-Model Ensemble (NMME) models besides comparing them with the persistent anomalies. The ANN predictions over all the four regions have higher ACC skill scores compared to the NMME model skill scores in the common period of 1982/83 to 2018/19. The ANN predicted SAT anomalies also have higher Hit rate and lower False alarm rate compared to the NMME predicted SAT anomalies. All these indicate that the ANN model is a promising tool for predicting the winter SAT anomalies over Japan.

scholarly journals The relationship between education, income, economic freedom and happiness

2020 ◽  
Vol 75 ◽  
pp. 03004
Author(s):  
Olena Stryzhak
Keyword(s):  
Economic Freedom ◽  
Rank Correlation ◽  
Modern Society ◽  
Strong Relationship ◽  
Quality Of Education ◽  
Economic Prosperity ◽  
Index Index ◽  
To Receive ◽  
The Relationship

Education is a factor for economic prosperity and social development in modern society. As well education allows its owner to receive a higher income and gives the opportunity for self-expression, creative fulfilment, as well as moral satisfaction from current activities. The life of educated people is not only longer, but also more interesting and informative. Moreover people with a higher level of education are happier also. In this aspect the purpose of the article is to determine the relationship between the quality of education, the degree of economic freedom, the level of income and the feeling of happiness. This paper presents results of the correlation analysis between indicators of education, income, happiness and economic freedom for 145 countries for 2018. The author of the work calculated Pearson (product-moment) correlation, the Spearman rank correlation, and Kendall’s Tau correlation in the Statistica. The analysis showed that Education Index has a strong relationship with Happiness Index, Economic Freedom of the World Index, Index of Economic Freedom and GDP. The analysis showed that education is closely related to the level of income and selfawareness of happiness. Education is also closely related to economic freedom. Also, the results of the study suggest that education not only contributes to an increase in income, but also makes persons happier.

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