• Title/Summary/Keyword: T_TIDE

Search Result 90, Processing Time 0.036 seconds

Accuracy Assessment of Tide Models in Terra Nova Bay, East Antarctica, for Glaciological Studies of DDInSAR Technique (DDInSAR 기반의 빙하연구를 위한 동남극 테라노바 만의 조위모델 정밀도 평가)

  • Han, Hyangsun;Lee, Joohan;Lee, Hoonyol
    • Korean Journal of Remote Sensing
    • /
    • v.29 no.4
    • /
    • pp.375-387
    • /
    • 2013
  • Accuracy assessment of tide models in polar ocean has to be performed to accurately analyze tidal response of glaciers by using Double-Differential Interferometric SAR (DDInSAR) technique. In this study, we used 120 DDInSAR images generated from 16 one-day tandem COSMO-SkyMed DInSAR pairs obtained for 2 years and in situ tide height for 11 days measured by a pressure type wave recorder to assess the accuracy of tide models such as TPXO7.1, FES2004, CATS2008a and Ross_Inv in Terra Nova Bay, East Antarctica. Firstly, we compared the double-differential tide height (${\Delta}\dot{T}$) for Campbell Glacier Tongue extracted from the DDInSAR images with that predicted by the tide models. Tide height (T) from in situ measurement was compared to that of the tide models. We also compared 24-hours difference of tide height ($\dot{T}$) from in situ tide height with that from the tide models. The root mean square error (RMSE) of ${\Delta}\dot{T}$, T and $\dot{T}$ decreased after the inverse barometer effect (IBE)-correction of the tide models, from which we confirmed that the IBE of tide models should be corrected requisitely. The RMSE of $\dot{T}$ and ${\Delta}\dot{T}$ were smaller than that of T. This was because $\dot{T}$ is the difference of tide height during temporal baseline of the DInSAR pairs (24 hours), in which the errors from mean sea level of the tide models and in situ tide, and the tide constituents of $S_2$, $K_2$, $K_1$ and $P_1$ used in the tide models were canceled. This confirmed that $\dot{T}$ and ${\Delta}\dot{T}$ predicted by the IBE-corrected tide models can be used in DDInSAR technique. It was difficult to select an optimum tide model for DDInSAR in Terra Nova Bay by using in situ tide height measured in a short period. However, we could confirm that Ross_Inv is the optimum tide model as it showed the smallest RMSE of 4.1 cm by accuracy assessment using the DDInSAR images.

Characteristics of Red Tide Blooms in the Lower reaches of Taehwa River (태화강 하류의 적조발생 특성)

  • Cho, Hong-Je;Yoon, Yeong-Bae;Kang, Ho-Seon;Yoon, Sung-Kyu
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.25 no.4
    • /
    • pp.453-462
    • /
    • 2011
  • This study was analyzed to determine the cause of red tide at 10 and 30 days antecedental rainfall, stage and discharge in the Taehwa River, tidal data of Ulsan port, also, it was analyzed variation of red tide population, salinity, BOD, COD, T-N, T-P at S1, S2 each point. Most of the red tide in the Taehwa River occurred by provision of proper nutrients with antecedent, the proximity between discharge and low-flow capacity, and stage and discharge of stabilized condition after the sea water was inflowed by maximum tide difference. Red tide population is not nearly related to the change of salinity, the Taehwa River seems specific features of Non-coastal rivers downstream, because red tide was occurred when salinity quite low-end condition.

The study on Estimate of Tidal Power Using Matlab T-tide Based on Tide Prediction (Matlab T-tide를 이용한 조위예측기반의 조력발전량 산정에 관한 연구)

  • Lee, Sung-Hun;Kwak, Hee-Jin;Kim, Jong-Deug;Lee, Eun-Chun;Kim, Ji-Chan;Jeon, Kyeong-Sik
    • Proceedings of the KIEE Conference
    • /
    • 2015.07a
    • /
    • pp.1048-1049
    • /
    • 2015
  • The sihwa tidal power plant is the first tidal power plant in korea and the biggest of the world. The tidal power turbine is operated by tidal energy. The tidal energy is generated by the relative motion of the earth and celestial masses specially the sun and the moon, which interact via gravitational forces. The tidal power is estimated by the predicted the tidal amplitude and phase. This paper gives a process of estimate of tidal power using Matlab T-tide based on tide prediction. The proposed method is tested using actual recorded data comparing to predicted date.

  • PDF

Comparison and analysis between TOPEX/POSEIDON Altimeter data and In-Situ Tide Gauge Data in the Eastern Asian Marginal Seas (동아시아 주변해역에서의 TOPEX/POSEIDON 위성 고도자료와 Tide Gauge 현장자료 간의 비교 및 해석 연구)

  • 윤홍주
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2000.10a
    • /
    • pp.606-609
    • /
    • 2000
  • These results indicate that the low-Sequency signal of T/P data (with periods greater than 200 days) can be interpreted most safely. Similarly to the case of the T/P data, corrections were also applied to those of tide gauge counterparts. Hence, when the 200-day effect was filtered out, the agreement between T/P and TG data sets was optimized.

  • PDF

Environmental Condition and Microbial Survey of the Tide Pools Densely Inhabited by Tigriopus japonicus MORI (동물성 플랑크톤 Harpacticoid, Tigriopus japonicus MORI가 서식하는 Tide Pool 생태계의 조사)

  • LEE Won Jae;TAGA Nobuo
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.18 no.1
    • /
    • pp.57-62
    • /
    • 1985
  • The three tide pools of Kanagawagen Aburatsubo coast, Japan were studied for 5 months (June-October, 1991) to know the physicochemical factors and changes of the microflora, In the tide pools salinity was ${\simeq}35\%0$, temperature range was $14{\sim}32^{\circ}C$ and pH range was $7.4{\sim}8.9$. Particulate organic carbon (POC) was $255{\sim}3980\;{\mu}g-at/l$, and total phosphate-P was $1.0{\sim}27.0\;{\mu}g-at/l$. The numbers of suspended bacteria and heterotrophic bacteria on the algae were $10^4{\sim}10^7/ml$ and $10^6{\sim}10^8/g$, respectively. Bacterial flora isolated from the Samples were Acinetobacter spp., Moraxella spp., Flavobacterium spp. and Pseudomonas spp., While Acinetobacter spp. was predominant among them. T. japonicus occurred dominantly with densities of $2200{\sim}7000/l$ during $August{\sim}september$. During this period the sharp increases of the unicellular microalgae and the protozoans were observed. According to the experimental results (POC, total phosphate-P, numbers and composition of bacterial flora), T. japonicus seemed to inhabit the environment with high eutrophication and high variability.

  • PDF

Investigation of marine bacteria for the food of Tigriopus japonicus Mori(Harpacticoida) (동물플랑크톤 Harpacticoid, Tigriopus japonicus Mori 배양에 유효한 해양세균의 탐색)

  • Lee Won-Jae;TAGA Nobuo
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.21 no.1
    • /
    • pp.50-56
    • /
    • 1988
  • In order to fine some proper bacterial food for Tigriopus japoncus, bacterial flora of the tide pool inhabited by the copepod has been isolated and tested as bacterial food. Food effect and optimum density of the bacteria in terms of survival rate of the copepod was measured in the larval and the adult stages. Among the 264 strains of isolated bacteria, Acinetobacter spp. Moraxella, spp., Flavobacterium spp. and Pseudomonas spp. were certified as effective food for the copepod. According to the experimental results, Acinetobacter spp. AG-3 was the most effective food for all the stages from nauplius to adult, while Moraxella spp. and Flavobacterium spp. were effective for copepodite stage, and Pseudomonas spp. for the adult stage only. The optimum density of bacteria for the food was about $10^6\;cell/ml$, which was the same average density of bacteria in the tide pool.

  • PDF

Comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels in the South Indian Ocean

  • Yoon, Hong-Joo
    • Proceedings of the KSRS Conference
    • /
    • 1998.09a
    • /
    • pp.70-75
    • /
    • 1998
  • The comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels was studied in the South Indian Ocean after Topex/Poseidon mission of about 3 years (11- 121 cycles) from January 1993 through December 1995. The user's handbook (AVISO) for sea surface height data process was used in this study Topex/Poseidon sea suface heights ($\zeta$$^{T/P}$), satellite data at the point which is very closed to Tide Gauge station, were chosen in the same latitude of Tide Gauge station. These data were re-sampled by a linear interpolation with the interval of about 10 days, and were filtered by the gaussian filter with a 60 day-window. Tide Gauge sea levels ($\zeta$$^{Argos}$, $\zeta$$^{In-situ}$ and $\zeta$$^{Model}$), were also treated with the same method as satellite data. The main conclusions obtained from the root-mean-square and correlation coefficient were as follows: 1) to Produce Tide Gauge sea levels from bottom pressure, in-situ data of METEO-FRANCE showed very good values against to the model data of ECMWF and 2) to compare Topex/Poseidon sea surface heights of Tide Gauge sea levels, the results of the open sea areas were better than those of the coast and island areas.

  • PDF

Identification of Red Tide-causing Organism and Characteristics of Red Tide Occurrence in the Oncheon Down Stream, Busan (온천천 하류 적조 원인생물의 동정 및 발생 특성)

  • Kim, Mi-hee;Ji, Hwa-seong;Cho, Jeong-goo;Cho, Sunja
    • Journal of Korean Society on Water Environment
    • /
    • v.34 no.3
    • /
    • pp.285-292
    • /
    • 2018
  • This study was performed in order to identify the red tide-causing organism and to understand the characteristics of the water quality during the winter of 2015 and 2016 in the Oncheon stream, a tidal river in Busan, where red tide often occurs in the wintertime. Two sites were selected on the stream and the surface water was sampled a total of 28 times during the experimental period. Twelve water quality characteristics, including water temperature, pH, DO, COD, total-N (T-N), total-P (T-P), and salinity were analyzed in order to test water quality. The cell numbers of cryptomonads were counted directly by microscopic observation. The nucleotide sequences of the partial 28S rRNA gene and psbA gene from metagenomic DNA, derived from each sampling site, were analyzed. According to the results, the alga most responsible for the bloom was identified as Teleaulax OC1 sp., which belongs to the cryptomonads. Three items of chl-a, pH, and DO were positively correlated with the cell numbers of the cryptomonads counted at the upper stream of the tidal area (St 1) while eight items of chl-a, TOC, BOD, total-N, COD, SS, pH, and DO were positively correlated with the cells located at the junction between the stream and Su-young river (St 2) in the order.

Local Movement of Shorebirds for Roosting between Ganghwa and Yeongjong Island in the West Coast of Korea

  • Kim, Hwa-Chung;Yoo, Jeong-Chil
    • The Korean Journal of Ecology
    • /
    • v.27 no.2
    • /
    • pp.73-77
    • /
    • 2004
  • Movement of shorebirds for roosting was studied to find their response to insufficient roosting area on Ganghwa Island. It was taken from two kinds of aspects of population fluctuation and direct observation of movement from March to October in 2002. Based on the data from their weekly fluctuation and flight observation, shorebirds on Ganghwa Island moved to roosts located far away. Shorebirds feeding at southern Ganghwa Island moved to Yeongjong Island for roosting during the spring tide period. High tide count showed that the number of shorebirds on Yeongjong Island increased strikingly, while the number of birds on Ganghwa Island decreased. As the tide level increased, the number of shorebirds on Ganghwa Island decreased in the fall migrating season (r$_{s}$= -0.81, p<0.001), whereas that on Yeongjong Island was not correlated significantly. Direct observation showed that some of the birds on the upper tidal zone of Ganghwa Island moved directly to the northern mudflat of Yeongjong Island during the flowing tide or dropped by flat zone on Seondu-ri. Insufficient coastal wetlands on Ganghwa Island induced them to move away from the island for roosting place and to endure costly flight energy expenditure. The development of wetlands on the southern Yeongjong Island would make them have no place available to roosts. Therefore this study proposes that shorebird roosts on Ganghwa Island should be created to conserve their habitat.t.

Sea Level Variations in the East Asian Marginal Seas by Topex/Poseidon Altimeter Data (Topex/Poseidon 고도계자료를 이용한 동북아시아 연변해역의 해수면 변화 연구)

  • Yoon, Hong-Joo;Kim, Sangwoo;Lee, Moon-Ock;Park, Il-Heum
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2001.10a
    • /
    • pp.300-303
    • /
    • 2001
  • The first 7 years of altimeter data from the TOPEX/POSEIDON (T/P) were analyzed to study the surface circulation and its variability in the East Asian Marginal Seas. Long term averaged T/P sea level time series data where compared with in situ sea level measurements from a float-operated type tide gauge around of south Korea and Japan. T/P data are a large contaminated by 60-day tidal aliasing effect, very near the alias periods of M2 and S2. When this 60-day effect is removed, the data agree well with the tide gauge data with 4.6 cm averaged RMS difference. The T/P derived sea level variability reveals clearly the well-known, strong current-topography such as Kuroshio. The T/P mean sea level of North Pacific (NP) was higher than Yellow Sea (YS) and East Sea (ES). The T/P sea level valibility, with strong eddy and meandaring, was the largest in eastern part of Japan and this variability was mainly due to the influence of bottom topography in Kuroshio Extention area.

  • PDF