scholarly journals Distribution Trend of the Bottom Water at the Bay Mouth of Jiaozhou Bay

2019 ◽  
Vol 136 ◽  
pp. 06013
Author(s):  
Dongfang Yang ◽  
Haoyuan Ren ◽  
Dong Yang ◽  
Haixia Li ◽  
Jing Fang

Based on the survey data of Jiaozhou Bay in May, June, July, August, September and October of 1980, the bottom water temperature and its horizontal distribution in Jiaozhou Bay were studied. The results showedthat the bottom water temperaturein Jiaozhou Bay rangedat a high level between 12.35℃to 25.72℃and a low level between 10.18℃to 24.58 ℃in May, June, July, August, September and October. From May to October, the bottom water temperature in Jiaozhou Bay was moderately high. In May, June, July and August, a high temperature zone formed around the waterinside the bay mouth, and the bottom water temperaturereached 12.35℃to 25.72℃.From May to August, the bottom water temperaturefirst increased in the watersinside the bay mouth, followed by the water at the bay mouth, withthe water outside the bay mouthas the end. In September and October, the temperature of the eastern coastal water outside Jiaozhou Bay ranged from 20.00℃to 24.43℃, and a high temperature zone formed around there. From September to October,the bottom water temperaturefirst decreased in the water inside the bay mouth, followed by the water at the bay mouth, with the water outside the bay mouthas the end. According to Yang Dongfang's definition of “Cryogenic Low Water Mass”, a cryogenic water mass formed in the bottom water at the bay mouthin September and extended widely among the water inside the bay mouth-at the bay mouth-in the southern part outside the bay mouthwith a temperature of 23.79℃to 23.91℃.

1978 ◽  
Vol 15 (6) ◽  
pp. 889-901 ◽  
Author(s):  
C. T. Schafer ◽  
F. J. E. Wagner

Common associations of mollusc and Foraminifera species were investigated in eastern Chaleur Bay, Gulf of St. Lawrence. Three depth-related biotopes are recognized. The distribution of species in this open bay environment appears to be controlled by substrate and (or) water mass characteristics. North–south differences in shallow water assemblages are related to summer bottom water temperature; calcareous Foraminifera and molluscs dominate in relatively high temperature environments. The influx of cold water (<1 °C) at intermediate depths (40–80 m) is reflected by an increase in the abundance of arenaceous Foraminifera species such as Reophax scottii, and by the absence of numerous mollusc species that are found at these depths elsewhere. A deep bay biotope (>80 m) can be recognized primarily on the basis of the mollusc species Yoldia limatula and Periploma fragile in association with the Foraminifera species Islandiella islandica. The observed mollusc–Foraminifera associations can be applied to paleoenvironmental and biostratigraphic studies of north temperate Holocene marine sediments.


2014 ◽  
Vol 11 (5) ◽  
pp. 2391-2422
Author(s):  
F. Miesner ◽  
A. Lechleiter ◽  
C. Müller

Abstract. Temperature fields in marine sediments are studied for various purposes. Often, the target of research is the steady state heat flow as a (possible) source of energy but there are also studies attempting to reconstruct bottom water temperature variations to understand more about climate history. The bottom water temperature propagates into the sediment to different depths, depending on the amplitude and period of the deviation. The steady state heat flow can only be determined when the bottom water temperature is constant while the bottom water temperature history can only be reconstructed when the deviation has an amplitude large enough or the measurements are taken in great depths. In this work, the aim is to reconstruct recent bottom water temperature history such as the last two years. To this end, measurements to depths of up to 6 m shall be adequate and amplitudes smaller than 1 K should be reconstructable. First, a commonly used forward model is introduced and analyzed: knowing the bottom water temperature deviation in the last years and the thermal properties of the sediments, the forward model gives the sediment temperature field. Next, an inversion operator and two common inversion schemes are introduced. The analysis of the inversion operator and both algorithms is kept short, but sources for further reading are given. The algorithms are then tested for artificial data with different noise levels and for two example data sets, one from the German North Sea and one from the Davis Strait. Both algorithms show good and stable results for artificial data. The achieved results for measured data have low variances and match to the observed oceanographic settings. Lastly, the desired and obtained accuracy are discussed. For artificial data, the presented method yields satisfying results. However, for measured data the interpretation of the results is more difficult as the exact form of the bottom water deviation is not known. Nevertheless, the presented inversion method seems rather promising due to its accuracy and stability for artificial data. Continuing to work on the development of more sophisticated models for the bottom water temperature, we hope to cover more different oceanographic settings in the future.


Author(s):  
Vaidotas Vaišis ◽  
Tomas Januševičius

The problem of noise is topical not only in Lithuania but the world over as well. The northern part of Klaipeda city is distinct for its industry and heavy traffic in the streets. Noise research was carried out in 17 selected measurement locations in the northern part of Klaipeda city. Noise measurements were taken in May, June, July, August, September, October and November. The measurements were made three times during the day: in the day time from 6 a.m. till 6 p.m., in the evening from 6 p.m. till 10 p.m. and at night from 10 p.m. till 6 a.m. The locations of the measurements are marked on the map. In order to distinguish the source of bigger noise between industry and transport, the northern part was divided into two belts. Industry is prevalent in the first belt, whereas the main troublemakers in the second belt are motor vehicles. The measured noise level is compared with permissible standards in measurement locations, where noise level is usually exceeded, and the analysis of noise levels is presented. In order to show the spread of noise in Klaipeda at all three times of the day more vividly, maps of isolines were compiled. Santrauka Triukšmas - ne tik Lietuvoje, bet ir visame pasaulyje aktuali problema. Klaipedos miesto šiaurine dalis yra išskirtine savo pramone ir intensyviu eismu gatvese. Triukšmo tyrimai atlikti šiaurineje Klaipedos miesto dalyje, 17‐oje pasirinktu matavimo vietu. Triukšmas matuotas gegužes, birželio, liepos, rugpjūčio, rugsejo, spalio ir lapkričio menesiais. Matavimai atlikti trimis paros laikais: diena nuo 6–18 valandos, vakare nuo 18–22 valandos ir nakti nuo 22–6 valandos. Matavimo vietos pateiktos žemelapyje. Siekiant nustatyti, kas kelia didesni triukšma ‐ pramone ar transportas, šiaurine miesto dalis suskirstyta i dvi zonas. Pirmojoje zonoje vyrauja pramone, o antrojoje zonoje pagrindinis triukšmo šaltinis automobiliai. Išmatuotas triukšmo lygis palygintas su leistinosiomis normomis. Pateikta matavimo vietu, kuriose dažniausiai viršijamas triukšmo lygis, triukšmo lygiu analize. Siekiant aiškiau parodyti, kaip triukšmas pasiskirsto Klaipedos mieste visais trimis paros laikais, sudaryti izoliniju žemelapiai. Резюме Шум является актуальной проблемой не только в Литве, но и во всем мире. Северная часть города Клайпеды является промышленным районом с интенсивным транспортным движением. Для исследования шума в этой части города было выбрано 17 мест замера. Шум измерялся с мая по ноябрь. Измерения проводились 3 раза в разное время суток: днем в 6–18 ч, вечером в 18–22 ч и ночью в 22–6 ч. Места замеров показаны на карте. С целью установить, что является бóльшим источником шума – промышленные предприятия или транспортные средства, северная часть города была поделена на две зоны. В первой зоне преобладали промышленные предприятия, а во второй – транспорт. Измеренный уровень шума сравнивался с разрешенным нормами. Для мест замеров, в которых чаще всего уровень шума превышал норму, предлагался анализ уровня шума. Для лучшего представления о распределении шума в городе Клайпеде в разное время суток были созданы карты изолиний.


2015 ◽  
Vol 86 ◽  
pp. 19-31 ◽  
Author(s):  
Lei Xing ◽  
Julian P. Sachs ◽  
Wenxian Gao ◽  
Shuqing Tao ◽  
Xiaochen Zhao ◽  
...  

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