scholarly journals Climatic changes of temperature, salinity and nutrients in the Amur Bay of the Japan Sea

2015 ◽  
Vol 183 (4) ◽  
pp. 186-199
Author(s):  
Yury I. Zuenko ◽  
Vladimir I. Rachkov
Keyword(s):  
Summer Monsoon ◽  
Large Scale ◽  
Japan Sea ◽  
Weather Conditions ◽  
Inorganic Phosphorus ◽  
Large River ◽  
Amur Bay ◽  
Sea Bottom ◽  
Recent Climate ◽  
Climate Scale

Recent climate-scale (> 3 decades) changes of water temperature, salinity, and concentration of inorganic phosphorus, silicon and nitrogen (nitrites and nitrates) are considered for the Amur Bay where Vladivostok is located ashore. Mean seasonal values of these parameters are determined for the 1980s and 2000s. In summer, the tendencies of climatic scale are noted of SST heightening, temperature at the sea bottom lowering, and nutrients depletion in the upper layer, except of nitrate. In general, the bay becomes more stratified and less productive, on the primary trophic level, but the nitrate income, presumably from atmosphere, prevents the productivity decreasing. Links of the changes with external conditions are analyzed, and the summer monsoon weakening is defined as their main reason that determines weather conditions over Primorye and cross-shelf exchange on its shelf. These processes related with the summer monsoon present the mechanism of large-scale climate changes downscaling to meso-scale level. Besides, there is concluded that the Amur Bay is more vulnerable to marine processes than to terrestrial ones, though it is subjected to the large river discharge.

scholarly journals State of aggregations and biological characteristics for mysid Neomysis awatschensis in the northern Amur Bay (Peter the Great Bay, Japan Sea)

2020 ◽  
Vol 200 (4) ◽  
pp. 922-934
Author(s):  
L. G. Sedova ◽  
L. L. Budnikova
Keyword(s):  
Average Length ◽  
Peter The Great Bay ◽  
Extended Period ◽  
Japan Sea ◽  
Weather Conditions ◽  
Amur Bay ◽  
Sex Structure ◽  
Peter The Great ◽  
Binocular Microscope ◽  
Maximum Body

Size and sex structure of estuarine-freshwater mysid Neomysis awatschensis in the northern Amur Bay is considered, time of their aggregations formation is determined, and their biomass is estimated on the data of surveys conducted in 2014–2019. The samples were collected at the depth of 0.5–2.0 m in the daytime in May-July. The catches were recalculated per 1 m3 of water. All collected mysids (2212 ind.) were measured under binocular microscope with accuracy of 0.1 mm, weighted by torsion scales with accuracy of 1 mg, and separated to males, females and juveniles. The females were differentiated by 5 stages of their development: 1) immature females with oostegetic rudiments; 2) oviparous females; 3) females with embryos in the marsupia bags without stalk-eyes with black pigment; 4) females with embryos in marsupia bags with black eyes; 5) spawned females with empty marsupii. Time and duration of N. awatschensis aggregating changed by years in dependence on hydrological and weather conditions; the aggregations were either monospecific or mixed with another mysid species — N. mirabilis. The maximum mysid biomass could exceed 500 g/m3 that was appropriate for commercial fishery. The maximum body length of mysid females was 13.7 mm, of males — 12.0 mm. The average length varied from 6.7 to 10.3 mm, being shorter in summer months than in May. Portion of males in the aggregations was always significant (16.3–50.7 %), portion of females varied from 8.7 to 52.5 %, portion of juveniles was the largest in June (29.9–75.0 %). The females to males ratio was 1 : 1 in May and July of 2014–2017, but males prevailed in June 2015 (1.0 : 1.9), whereas females prevailed in June 2016 (1.8 : 1.0). Spawning of the mysids was the most intensive in May-June, though females had embryos at different stages of development in all samples that indicated an extended period of reproduction.

scholarly journals Mechanisms of subtropical plankton transport into the coastal waters of southern Primorye, a case of Paracalanus parvus

2016 ◽  
Vol 184 (1) ◽  
pp. 241-252
Author(s):  
Victoria V. Nadtochy ◽  
Yury I. Zuenko
Keyword(s):  
Summer Monsoon ◽  
Coastal Waters ◽  
Species Abundance ◽  
Japan Sea ◽  
Early Summer ◽  
High Abundance ◽  
Southern Primorye ◽  
Climatic Trend ◽  
Amur Bay ◽  
Paracalanus Parvus

Results of long-term studies of zooplankton species in the Amur Bay (Japan Sea) are analyzed. Two seasonal «waves» of the allochtonous species are defined: the first in the early summer that is formed mainly by inter-zonal copepods spawning in the deep layers ( Metridia pacifica , Neocalanus plumchrus, Calanus glacialis ) and the second in the late summer that is represented by warm-water copepods of subtropical origin ( Calanus pacificus and Paracalanus parvus ) obviously transported from the southern Japan Sea by currents. The latter species is able to dominate in the zooplankton community of coastal waters in the early-autumn season. Variations of this mass species abundance in the Amur Bay under changes of wind-driven upwelling/downwelling circulation are investigated using an empirical advective model of its cross-shelf transport. There is found that strong summer southern on-shore winds (summer monsoon) are favourable for its high abundance but in these conditions it is transported toward the coast by the deep compensatory flow developed only after the summer monsoon change to the winter monsoon with opposite direction; that’s why the high abundance is observed in autumn, in September-October. In the years with weak summer monsoon the species is transported to the bay in mass by the surface on-shore wind-driven flow earlier, in August, but its number decreases after the monsoon change, so the maximum of abundance is not high. Patterns of the transport by cross-shelf currents depend supposedly on the depth of plankton concentration. Recent strengthening of summer monsoon causes heightening of P. parvus abundance in the coastal waters at southern Primorye, up to extreme high values in 2013, but climatic trend of the summer monsoon intensity is negative, so decreasing of this species transport toward Primorye coast and its abundance in the coastal waters, as the Amur Bay, can be expected in the nearest future.

scholarly journals BIOLOGICAL CHARACTERISTICS OF MYSID NEOMYSIS MIRABILIS IN DEPENDENCE ON ITS ENVIRONMENTS (PETER THE GREAT BAY, JAPAN SEA)

2020 ◽  
Vol 200 ◽  
pp. 101-117
Author(s):  
L. G. Sedova ◽  
L. L. Budnikova
Keyword(s):  
Peter The Great Bay ◽  
Japan Sea ◽  
Weather Conditions ◽  
The Body ◽  
Stages Of Development ◽  
Amur Bay ◽  
Sex Structure ◽  
Peter The Great ◽  
Great Bay ◽  
External Part

Size and sex structure of mysid Neomysis mirabilis in Peter the Great Bay is studied. The net samples (160 and 260 per year) were collected at the depth of 0.5–2.0 m in the southern external part of the secondary Amur Bay (at Popov and Reineke Islands) and in its northern internal part, over the total area of approximately 3 km2 , in the daytime in May-September from 2014 to 2017. The catch was recalculated per 1 m3 of water. The water temperature was measured and weather conditions were recorded. All mysids (2926 ind.) were measured under binocular microscope with accuracy of 0.1 mm, weighted by torsion scales with accuracy of 1 mg, and separated to males, females and juveniles. The females were differentiated by 5 stages of development: 1) immature females with oostegetic rudiments, 2) oviparous females, 3) females with embryos in the marsupia bags without stalk-eyed with black pigment, 4) females with embryos in marsupia bags with black eyes, 5) spawned females with empty marsupii. The females prevailed: 71.3–97.0 % in the southern Amur Bay and 39.0–56.7 % in the northern Amur Bay, while the portion of males was 2.2–28.7 % and 20.9–43.3 %, accordingly. The body length varied from 3.0 to 23.5 mm; the females and males had the same sizes, on average 14.5–15.4 mm in the southern Amur Bay and 8.3–11.2 mm in the northern Amur Bay, with slight decreasing from spring to summer. The spawning was extended in time because of several generations changing. Mysid females with eggs, their embryos at different stages of development, and juveniles of different size were presented permanently. Aggregations of N. mirabilis formed for a short time starting in middle April — middle July in the southern Amur Bay and in middle May — late July in the northern Amur Bay. The mysid biomass in the aggregations was 3–5 g/m2 and 10–500 g/m2 in these areas, respectively, that is appropriate for the commercial fishery. Spatial difference of the mysid biological parameters and abundance is explained by different environmental conditions in the internal and external areas of the Amur Bay.

scholarly journals Performance of Strawberry Varieties Developed for Perennial Matted-Row Production in Annual Plasticulture in a Cold Climate Region

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1407
Author(s):  
Courtney A. Weber
Keyword(s):  
Large Scale ◽  
Fruit Size ◽  
Weather Conditions ◽  
Cold Climate ◽  
Annual Production ◽  
High Yield ◽  
Production Cycle ◽  
Late Season ◽  
Berry Weight ◽  
High Yields

Annual plasticulture production of strawberries promises superior weed control, fruit quality and yields. However, strawberry varieties adapted for perennial, matted-row production and local markets in cold climate regions have not been widely tested for adaptation to an annual production cycle. Productivity of seven short-day varieties developed for matted-row and/or annual production was examined in an annual plasticulture system in two consecutive trials in central NY (lat. 42.87° N, long. 76.99° W) harvested in 2013 and 2014. ‘Flavorfest’ demonstrated good performance in Trial 1 with high yield (390 g/plant) and large fruit size (13.9 g mean berry weight). ‘Jewel’ was shown to be well adapted to the annual plasticulture system with consistently high yields (330 and 390 g/plant) that equaled or surpassed other varieties and had moderate fruit size. ‘Chandler’ performed similarly to previous trials conducted in warmer regions with yield (340 g/plant) and fruit size (9.8 g mean berry weight) similar to ‘Jewel’. ‘Clancy’ yielded less but was consistent from year to year. The late season varieties Seneca and Ovation showed marked variability between years, possibly due to drastically different temperatures during flowering and fruit development in Trial 1 compared to Trial 2. High temperatures in Trial 1 likely caused higher early fruit yield, a compressed season and a precipitous decline in fruit size in the later season, thus reducing yield in the late season. Survival after a second dormant period was poor resulting in a small second harvest and reduced fruit size. Overall, the system demonstrated many of the expected benefits but may be more sensitive to weather conditions in the region. While many varieties developed for matted-row production may work well in an annual plasticulture system, not all varieties are equally adapted. Performance of each variety should be determined independently before large scale adoption by growers.

scholarly journals Remote and local drivers of Pleistocene South Asian summer monsoon precipitation: A test for future predictions

2021 ◽  
Vol 7 (23) ◽  
pp. eabg3848
Author(s):  
Steven C. Clemens ◽  
Masanobu Yamamoto ◽  
Kaustubh Thirumalai ◽  
Liviu Giosan ◽  
Julie N. Richey ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
South Asian ◽  
Summer Monsoon ◽  
Large Scale ◽  
Asian Summer Monsoon ◽  
Precipitation Amount ◽  
Monsoon Precipitation ◽  
Orbital Eccentricity ◽  
South Asian Summer Monsoon ◽  
Asian Summer

South Asian precipitation amount and extreme variability are predicted to increase due to thermodynamic effects of increased 21st-century greenhouse gases, accompanied by an increased supply of moisture from the southern hemisphere Indian Ocean. We reconstructed South Asian summer monsoon precipitation and runoff into the Bay of Bengal to assess the extent to which these factors also operated in the Pleistocene, a time of large-scale natural changes in carbon dioxide and ice volume. South Asian precipitation and runoff are strongly coherent with, and lag, atmospheric carbon dioxide changes at Earth’s orbital eccentricity, obliquity, and precession bands and are closely tied to cross-equatorial wind strength at the precession band. We find that the projected monsoon response to ongoing, rapid high-latitude ice melt and rising carbon dioxide levels is fully consistent with dynamics of the past 0.9 million years.

A Streamflow and Water Level Forecasting Model for the Ganges, Brahmaputra, and Meghna Rivers with Requisite Simplicity

2018 ◽  
Vol 19 (1) ◽  
pp. 201-225 ◽  
Author(s):  
Wahid Palash ◽  
Yudan Jiang ◽  
Ali S. Akanda ◽  
David L. Small ◽  
Amin Nozari ◽  
...  
Keyword(s):  
Water Level ◽  
Lead Time ◽  
Large Scale ◽  
Predictive Ability ◽  
Large River ◽  
Modeling Framework ◽  
Forecasting Accuracy ◽  
Weather Model ◽  
And Performance ◽  
The Ganges

A forecasting lead time of 5–10 days is desired to increase the flood response and preparedness for large river basins. Large uncertainty in observed and forecasted rainfall appears to be a key bottleneck in providing reliable flood forecasting. Significant efforts continue to be devoted to developing mechanistic hydrological models and statistical and satellite-driven methods to increase the forecasting lead time without exploring the functional utility of these complicated methods. This paper examines the utility of a data-based modeling framework with requisite simplicity that identifies key variables and processes and develops ways to track their evolution and performance. Findings suggest that models with requisite simplicity—relying on flow persistence, aggregated upstream rainfall, and travel time—can provide reliable flood forecasts comparable to relatively more complicated methods for up to 10 days lead time for the Ganges, Brahmaputra, and upper Meghna (GBM) gauging locations inside Bangladesh. Forecasting accuracy improves further by including weather-model-generated forecasted rainfall into the forecasting scheme. The use of water level in the model provides equally good forecasting accuracy for these rivers. The findings of the study also suggest that large-scale rainfall patterns captured by the satellites or weather models and their “predictive ability” of future rainfall are useful in a data-driven model to obtain skillful flood forecasts up to 10 days for the GBM basins. Ease of operationalization and reliable forecasting accuracy of the proposed framework is of particular importance for large rivers, where access to upstream gauge-measured rainfall and flow data are limited, and detailed modeling approaches are operationally prohibitive and functionally ineffective.

scholarly journals Large-scale extreme rainfall producing synoptic systems of the Indian summer monsoon

2020 ◽  
Author(s):  
Akshaya C Nikumbh ◽  
Arindam Chakraborty ◽  
G S Bhat ◽  
Dargan M. W. Frierson
Keyword(s):  
Summer Monsoon ◽  
Indian Summer Monsoon ◽  
Large Scale ◽  
Extreme Rainfall

scholarly journals A High-Speed, Light-Weight Scalar Magnetometer Bird for km Scale UAV Magnetic Surveying: On Sensor Choice, Bird Design, and Quality of Output Data

2021 ◽  
Vol 13 (4) ◽  
pp. 649
Author(s):  
Arne Døssing ◽  
Eduardo Lima Simoes da Silva ◽  
Guillaume Martelet ◽  
Thorkild Maack Rasmussen ◽  
Eric Gloaguen ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Signal To Noise Ratio ◽  
Regional Scale ◽  
Weather Conditions ◽  
Light Weight ◽  
Output Data ◽  
Efficient Manner ◽  
Flexible System ◽  
Scalar Data

Magnetic surveying is a widely used and cost-efficient remote sensing method for the detection of subsurface structures at all scales. Traditionally, magnetic surveying has been conducted as ground or airborne surveys, which are cheap and provide large-scale consistent data coverage, respectively. However, ground surveys are often incomplete and slow, whereas airborne surveys suffer from being inflexible, expensive and characterized by a reduced signal-to-noise ratio, due to increased sensor-to-source distance. With the rise of reliable and affordable survey-grade Unmanned Aerial Vehicles (UAVs), and the developments of light-weight magnetometers, the shortcomings of traditional magnetic surveying systems may be bypassed by a carefully designed UAV-borne magnetometer system. Here, we present a study on the development and testing of a light-weight scalar field UAV-integrated magnetometer bird system (the CMAGTRES-S100). The idea behind the CMAGTRES-S100 is the need for a high-speed and flexible system that is easily transported in the field without a car, deployable in most terrain and weather conditions, and provides high-quality scalar data in an operationally efficient manner and at ranges comparable to sub-regional scale helicopter-borne magnetic surveys. We discuss various steps in the development, including (i) choice of sensor based on sensor specifications and sensor stability tests, (ii) design considerations of the bird, (iii) operational efficiency and flexibility and (iv) output data quality. The current CMAGTRES-S100 system weighs ∼5.9 kg (including the UAV) and has an optimal surveying speed of 50 km/h. The system was tested along a complex coastal setting in Brittany, France, targeting mafic dykes and fault contacts with magnetite infill and magnetite nuggets (skarns). A 2.0 × 0.3 km area was mapped with a 10 m line-spacing by four sub-surveys (due to regulatory restrictions). The sub-surveys were completed in 3.5 h, including >2 h for remobilisation and the safety clearance of the area. A noise-level of ±0.02 nT was obtained and several of the key geological structures were mapped by the system.

scholarly journals Random Regret-Minimization Model for Emergency Resource Preallocation at Freeway Accident Black Spots

2018 ◽  
Vol 2018 ◽  
pp. 1-13
Author(s):  
Siliang Luan ◽  
Qingfang Yang ◽  
Wei Wang ◽  
Zhongtai Jiang ◽  
Ruru Xing ◽  
...  
Keyword(s):  
Large Scale ◽  
Traffic Accidents ◽  
Weather Conditions ◽  
Time Cost ◽  
Frequency Method ◽  
Regret Minimization ◽  
Accident Probability ◽  
Black Spots ◽  
Random Regret Minimization

The preallocation of emergency resources is a mechanism increasing preparedness for uncertain traffic accidents under different weather conditions. This paper introduces the concept of accident probability of black spots and an improved accident frequency method to identify accident black spots and obtain the accident probability. At the same time, we propose a three-stage random regret-minimization (RRM) model to minimize the regret value of the attribute of overall response time, cost, and demand, which allocates limited emergency resources to more likely to happen accident spots. Due to the computational complexity of our model, a genetic algorithm is developed to solve a large-scale instance of the problem. A case study focuses on three-year rainy accidents’ data in Weifang, Linyi, and Rizhao of China to test the correctness and validity of the application of the model.

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