Seasonal Variability in Middepth Gyral Circulation Patterns in the Central East/Japan Sea as Revealed by Long-Term Argo Data

2016 ◽  
Vol 46 (3) ◽  
pp. 937-946 ◽  
Author(s):  
Sok Kuh Kang ◽  
Young Ho Seung ◽  
Jong Jin Park ◽  
Jae-Hun Park ◽  
Jae Hak Lee ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Seasonal Variability ◽  
Japan Sea ◽  
Circulation Pattern ◽  
Japan Basin ◽  
Wind Stress Curl ◽  
Argo Data ◽  
Circulating Water ◽  
Significant Seasonal Variation ◽  
Water Columns

AbstractTrajectories of Argo floats deployed in the East/Japan Sea from 2001 to 2014 reveal that the middepth gyral circulation pattern of the Japan basin, the central part of the East/Japan Sea, undergoes a seasonal variation. The middepth circulation of the Japan basin is found to be characterized usually by the gyres trapped to the east of the Bogorov Rise (E-gyres) and those extending farther westward into the whole basin (BW-gyres). The E-gyre trajectories are generally associated with the turning of the floats toward deeper regions off the isobaths. This occurs in winter either on the northern or eastern side of the eastern Japan basin. It seems that the upstream part of the otherwise BW-gyre is subject to a strong negative wind stress curl in winter, and there the circulating water columns are driven toward the deeper region, thus triggering the formation of the E-gyre. The topographic effect associated with the Bogorov Rise seems to interfere thereafter in the process of determining the passage of the E-gyre. Otherwise, the water columns continue to flow along the isobaths, hence maintaining the BW-gyre. To the knowledge of the authors, this is the first observational evidence of seasonal variability in the middepth gyral circulation pattern in the East/Japan Sea. It suggests that oceanic middepth circulation, usually known to be quasi steady or slowly varying on climatological time scales, might also undergo a significant seasonal variation as it does in the East/Japan Sea.

scholarly journals Hydrogeochemistry and surface water quality assessment of IB valley coalfield area, India

2021 ◽  
Vol 11 (9) ◽  
Author(s):  
Bishnu Prasad Sahoo ◽  
Himanshu Bhushan Sahu ◽  
Dhruti Sundar Pradhan
Keyword(s):  
Water Quality ◽  
Heavy Metal ◽  
Seasonal Variation ◽  
Surface Water ◽  
Water Samples ◽  
Nickel Aluminum ◽  
Acid Mine ◽  
Significant Seasonal Variation ◽  
Cadmium Selenium ◽  
High Degree

AbstractCoal mining and ancillary activities have the potential to cause water pollution characterized by acid mine drainage, acid mine leachates, extreme pH conditions and heavy metal contaminations. In the present work, 33 water samples in premonsoon and 34 water samples in monsoon were collected from the surface water bodies of Ib Valley coalfield, India for hydrogeochemical analysis. In premonsoon, pH, TSS, Turbidity, DO, BOD, COD, Magnesium, Cadmium, Selenium, Nickel, Aluminum and in monsoon, pH, TSS, Turbidity, DO, BOD, COD, Iron, Cadmium, Selenium, Nickel and Aluminum were nonconforming to the permissible limit set by the Bureau of Indian Standards, World Health Organisation and Ministry of Environment, Forest and Climate Change, Government of India. The average BOD/COD ratio of less than 0.6 in both seasons indicated Ib valley coalfield water was not fairly biodegradable. The analysis of variance (ANOVA) revealed that significant seasonal variation (p < 0.05) was observed in the hydro-chemical parameters viz. TSS, turbidity, redox potential, acidity, total hardness, bicarbonate alkalinity, chloride, sulfate, nitrate, sodium, calcium, magnesium, iron, cadmium, chromium and magnesium during the entire sampling period. Whereas, no significant seasonal variation (p > 0.05) was observed in pH, EC, TDS, DO, BOD, residual chlorine, COD, oil and grease, fluoride, potassium, zinc, copper, selenium, nickel, aluminum, boron, silica, temperature, salinity, cyanide and phenol. Water Quality Index revealed that 39.39% and 35.29% samples belong to poor water quality category in premonsoon and monsoon, respectively. As per Heavy Metal Pollution Index, Degree of Contamination (Cd) and Heavy metal evaluation index, medium degree of pollution were exhibited by 51.52%, 30.30% and 45.45% samples in premonsoon and 20.59%, 35.29% and 26.47% samples in monsoon. Whereas, 5.88%, 2.94% and 5.88% samples were having high degree of pollution in monsoon and 15.15% samples caused high degree of pollution with respect to Cd in premonsoon. However, EC, Na%, PI, SAR and RSC values suggested that the water can be used for irrigation. Water type of the region had been found to be Ca–Mg–Cl–SO4 by Piper diagram.

scholarly journals Seasonal variability of SST fronts and winds on the southeastern continental shelf of Brazil

2019 ◽  
Vol 69 (11-12) ◽  
pp. 1387-1399 ◽  
Author(s):  
Huan-Huan Chen ◽  
Yiquan Qi ◽  
Yuntao Wang ◽  
Fei Chai
Keyword(s):  
Continental Shelf ◽  
Wind Stress ◽  
Seasonal Variability ◽  
Detection Algorithm ◽  
Coupling Coefficients ◽  
Seafloor Topography ◽  
Wind Stress Curl ◽  
Large Coupling ◽  
The Impact ◽  
Sst Fronts

Abstract Fourteen years (September 2002 to August 2016) of high-resolution satellite observations of sea surface temperature (SST) data are used to describe the frontal pattern and frontogenesis on the southeastern continental shelf of Brazil. The daily SST fronts are obtained using an edge-detection algorithm, and the monthly frontal probability (FP) is subsequently calculated. High SST FPs are mainly distributed along the coast and decrease with distance from the coastline. The results from empirical orthogonal function (EOF) decompositions reveal strong seasonal variability of the coastal SST FP with maximum (minimum) in the astral summer (winter). Wind plays an important role in driving the frontal activities, and high FPs are accompanied by strong alongshore wind stress and wind stress curl. This is particularly true during the summer, when the total transport induced by the alongshore component of upwelling-favorable winds and the wind stress curl reaches the annual maximum. The fronts are influenced by multiple factors other than wind forcing, such as the orientation of the coastline, the seafloor topography, and the meandering of the Brazil Current. As a result, there is a slight difference between the seasonality of the SST fronts and the wind, and their relationship was varying with spatial locations. The impact of the air-sea interaction is further investigated in the frontal zone, and large coupling coefficients are found between the crosswind (downwind) SST gradients and the wind stress curl (divergence). The analysis of the SST fronts and wind leads to a better understanding of the dynamics and frontogenesis off the southeastern continental shelf of Brazil, and the results can be used to further understand the air-sea coupling process at regional level.

scholarly journals Physico-chemical attributes of water of Hakaluki Haor, Sylhet, Bangladesh

2016 ◽  
Vol 3 (2) ◽  
pp. 67-72
Author(s):  
Md Tajul Islam ◽  
M Mahfuzur Rahman ◽  
Hassan Mahmud
Keyword(s):  
Water Quality ◽  
Seasonal Variation ◽  
Water Samples ◽  
Water Quality Assessment ◽  
Inorganic Pollutants ◽  
Chemical Parameters ◽  
Ph Values ◽  
Physico Chemical ◽  
Significant Seasonal Variation ◽  
Chemical Attributes

Water quality assessment has been carried out in the Hakaluki Haor of greater Sylhet district during May, 2013 to February, 2014. Water samples were collected from 5 spots during 4 seasons and a total of 15 physico-chemical parameters were studied. Significant seasonal variation was observed in all seasons among physico-chemical parameters. pH values varied from 5.9 - 7.1, water temperature varied from 23.7 – 26.7OC, transference varied from 23-53 cm, TSS varied from 18.1-192 mg/l, TDS varied 25-193.5 mg/l, EC varied from 30-680 ?s/cm , DO content of water varied from 4.6 - 5.6mg/l, BOD varied from 0.2-2.614 mg/l, COD varied from 38-312 mg/l, NO3-N varied from 0.1-30.4 mg/l, NH3 varied from 0.9-2.18 mg/l, alkalinity varied from 12-42 mg/l and PO4 varied from 0.9 -13.4 (mg/l). Agricultural and inorganic pollutants have been observed as the main causes of the Haor water pollution.Jahangirnagar University J. Biol. Sci. 3(2): 67-72, 2014 (December)

scholarly journals High-salinity intermediate water of the Japan Sea in the eastern Japan Basin

2001 ◽  
Vol 106 (C6) ◽  
pp. 11437-11450 ◽  
Author(s):  
Tatsuro Watanabe ◽  
Mitsuyuki Hirai ◽  
Haruya Yamada
Keyword(s):  
High Salinity ◽  
Japan Sea ◽  
Intermediate Water ◽  
Japan Basin ◽  
The Japan Sea ◽  
Eastern Japan

scholarly journals Mucormycosis in the Eastern Mediterranean: a seasonal disease

2005 ◽  
Vol 134 (2) ◽  
pp. 341-346 ◽  
Author(s):  
M. R. AL-AJAM ◽  
A. R. BIZRI ◽  
J. MOKHBAT ◽  
J. WEEDON ◽  
L. LUTWICK
Keyword(s):  
Seasonal Variation ◽  
Fungal Infection ◽  
Pulmonary Infection ◽  
Pattern Analysis ◽  
Eastern Mediterranean ◽  
Seasonal Pattern ◽  
Atmospheric Concentration ◽  
Tel Aviv ◽  
Significant Seasonal Variation ◽  
Immunocompromised Hosts

Mucormycosis is a fairly rare fungal infection caused by ubiquitous fungi of the order Mucorales and primarily affects immunocompromised hosts. A series of 16 cases of invasive mucormycosis admitted to three referral centres in Beirut, Lebanon between 1981 and 1999 is described. It includes 12 patients with rhinocerebral, three with cutaneous, and one with pulmonary infection. Onset of symptoms occurred in the summer and autumn in 15 out of 16 patients, showing a statistically significant seasonal variation (P=0·007) A recent report of 19 patients from Tel Aviv describes a strikingly similar seasonal pattern. Studies on atmospheric concentration of Mucorales spores in the Eastern Mediterranean are lacking. Weather pattern analysis in Beirut revealed clustering of onset of invasive mucormycosis at the end of a dry, warm period, which begins around May and ends in October. Mucormycosis incidence appears to be seasonal in the Eastern Mediterranean.

89. Seasonal Variation of the Percentage Butterfat Content of Milk. An Examination of the Results of Certain Individual Cow Tests

1935 ◽  
Vol 6 (1) ◽  
pp. 1-5 ◽  
Author(s):  
C. D. Oxley
Keyword(s):  
Seasonal Variation ◽  
Standard Deviation ◽  
Seasonal Variability ◽  
Milk Samples ◽  
Sources Of Error ◽  
The Mean ◽  
Morning Milk

Figures showing the means and the standard deviation of butterfat percentage of milk samples, at the afternoon and morning milkings res-pectively, during the four quarters of the year are presented.The probable sources of error due to the nature of the sample are discussed and the seasonal variability of mean and of standard deviation is considered.The likelihood of the mean of afternoon or of morning milk failing to reach certain specified minima during the respective seasons is calculated.

scholarly journals Seasonal variation and change trends for quit smoking: evidence from Internet search engine query data

2019 ◽  
Author(s):  
Fang Wang ◽  
Dingtao Hu ◽  
Xiaoqi Lou ◽  
Nana Meng ◽  
Qiaomei Xie ◽  
...  
Keyword(s):  
Time Series ◽  
Smoking Cessation ◽  
Seasonal Variation ◽  
New Zealand ◽  
Google Trends ◽  
Internet Search ◽  
Quit Smoking ◽  
Significant Seasonal Variation ◽  
The Usa ◽  
The Uk

Abstract Background: The outcomes of smoking have generated considerable clinical interest in recent years. Although people from different countries are more interested to the topic of quit smoking during the winter, few studies have tested this hypothesis. The current study aimed to quantify public interest in quit smoking via Google.Methods: We use Google Trends to obtain the Internet search query volume for terms relating to quit smoking for major northern and southern hemisphere countries in this research. Normally search volumes for the term “quit smoking + stop smoking + smoking cessation” were retrieved within the USA, the UK, Canada, Ireland, New Zealand and Australia from January 2004 to December 2018. Seasonal effects were investigated using cosinor analysis and seasonal decomposition of time series models.Results: Significant seasonal variation patterns in those search terms were revealed by cosinor analysis and demonstrated by the evidence from Google Trends analysis in the representative countries including the USA (pcos = 2.36×10-7), the UK (pcos < 2.00×10-16), Canada (pcos < 2.00×10-16), Ireland (pcos <2.00×10-16) ,Australia (pcos = 5.13×10-6) and New Zealand (pcos = 4.87×10-7). Time series plots emphasized the consistency of seasonal trends with peaks in winter / late autumn by repeating in nearly all years. The overall trend of search volumes, observed by dynamic series analysis, declined from 2004 to 2018.Conclusions: The preliminary evidence from Google Trends search tool showed a significant seasonal variation and decreasing trend for the RSV of quit smoking. Our novel findings in smoking cessation epidemiology need to be verified with further studies, and the mechanisms underlying these findings must be clarified.

scholarly journals Estimation of the Particulate Organic Carbon to Chlorophyll-a Ratio Using MODIS-Aqua in the East/Japan Sea, South Korea

2020 ◽  
Vol 12 (5) ◽  
pp. 840 ◽  
Author(s):  
Dabin Lee ◽  
SeungHyun Son ◽  
HuiTae Joo ◽  
Kwanwoo Kim ◽  
Myung Joon Kim ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Particulate Organic Carbon ◽  
Chlorophyll A ◽  
Primary Productivity ◽  
Seasonal Variability ◽  
Japan Sea ◽  
Global Ocean ◽  
Phytoplankton Communities

In recent years, the change of marine environment due to climate change and declining primary productivity have been big concerns in the East/Japan Sea, Korea. However, the main causes for the recent changes are still not revealed clearly. The particulate organic carbon (POC) to chlorophyll-a (chl-a) ratio (POC:chl-a) could be a useful indicator for ecological and physiological conditions of phytoplankton communities and thus help us to understand the recent reduction of primary productivity in the East/Japan Sea. To derive the POC in the East/Japan Sea from a satellite dataset, the new regional POC algorithm was empirically derived with in-situ measured POC concentrations. A strong positive linear relationship (R2 = 0.6579) was observed between the estimated and in-situ measured POC concentrations. Our new POC algorithm proved a better performance in the East/Japan Sea compared to the previous one for the global ocean. Based on the new algorithm, long-term POC:chl-a ratios were obtained in the entire East/Japan Sea from 2003 to 2018. The POC:chl-a showed a strong seasonal variability in the East/Japan Sea. The spring and fall blooms of phytoplankton mainly driven by the growth of large diatoms seem to be a major factor for the seasonal variability in the POC:chl-a. Our new regional POC algorithm modified for the East/Japan Sea could potentially contribute to long-term monitoring for the climate-associated ecosystem changes in the East/Japan Sea. Although the new regional POC algorithm shows a good correspondence with in-situ observed POC concentrations, the algorithm should be further improved with continuous field surveys.

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