scholarly journals SAND ACCUMULATION IN WAVE-SHELTER ZONE OF OHARAI PORT AND CHANGE IN GRAIN SIZE OF SEABED MATERIALS ON NEARBY COAST

2011 ◽  
Vol 1 (32) ◽  
pp. 63
Author(s):  
Takeo Matsu-ura ◽  
Takaai Uda ◽  
Takayuki Kumada ◽  
Michio Sumiya

Beach changes around Oharai Port facing the Pacific Ocean were investigated using bathymetric survey data collected over 25 years between 1979 and 2004. Between the south and offshore breakwaters of Oharai Port, 1.50×106 m3 of fine sand was deposited in this period, i.e., at an annual rate of 6.0×104 m3/yr, which was originally supplied from the Naka River 3 km north of the port. Also in the wave-shelter zone of the offshore breakwater south of the port, 7.0×106 m3 of fine sand was deposited between 1979 and 2004 at an annual rate of 2.8×105 m3/yr, which was transported by the northward longshore sand transport induced from outside to inside the wave-shelter zone of the offshore breakwater, resulting in severe beach erosion on the south coast outside the wave-shelter zone. Taking into consideration the fact that sand transport to the Kashimanada coast is now completely obstructed by the port breakwaters, sand bypassing and sand back passing to the coast from the sand deposition zone of Oharai Port are required.

Author(s):  
Peter Dauvergne

Chapters 2–6 survey the political and socioeconomic forces underlying the global sustainability crisis. Understanding the scale and depth of contemporary forces of capitalism and consumerism requires a close look at the consequences of imperialism and colonialism on patterns of violence and exploitation. This chapter begins this process of understanding by sketching the history of ecological imperialism after 1600, seeing this as a reasonable starting date for the beginning of what many scholars are now calling the Anthropocene Epoch (or the age of humans, replacing the geologic epoch of the Holocene beginning 12,000 years ago). It opens with Captain Pedro Fernandes de Queirós’s voyage across the Pacific Ocean in 1605–06 to “discover” modern-day Vanuatu, before turning to look more globally at the devastation of imperialism – and later colonialism – for the South Pacific, the Americas, Africa, and Asia. Over this time conquerors enslaved and murdered large numbers of indigenous people; cataclysmic change came as well, however, from the introduction of European diseases, plants, and animals. This chapter’s survey of imperialism, colonialism, and globalization sets the stage for Chapter 3, which explores the devastating history of the South Pacific island of Nauru after 1798.


1912 ◽  
Vol 9 (6) ◽  
pp. 258-265 ◽  
Author(s):  
James Romanes

During a visit to Costa llica in the year 1910 I was able to spend about ten days in the comparatively little-known peninsula of Nicoya. The trend of the peninsula is north-west to south-east, and it is separated from the mainland by the Gulf of Nicoya, a shallow arm of the Pacific Ocean, which opens to the sea on the south-east.


2005 ◽  
Vol 35 (3) ◽  
pp. 323-335 ◽  
Author(s):  
Christopher S. Meinen

Abstract Altimetric observations of sea surface height anomaly (SSHA) from the TOPEX/Poseidon and ERS satellites, hydrography, and the ECMWF and Florida State University wind products are used to track warm water (≥20°C) as it is exchanged between the equatorial Pacific Ocean and the higher latitudes during 1993–2003. The large El Niño event of 1997–98 resulted in a significant discharge of warm water toward the higher latitudes within the interior of the Pacific Ocean. The exchange of anomalous warm water volume with the Northern Hemisphere appears to be blocked under the intertropical convergence zone, consistent with most current ideas on the time-mean tropical–subtropical exchange. Little of the warm water discharged northward across 5° and 8°N during the 1997–98 El Niño event could be traced as far as 10°N. To the south, however, these anomalous volumes of warm water were visible at least as far as 20°S, primarily in the longitudes around 130°–160°W. In both hemispheres most of the warm water appeared to flow westward before returning to the Tropics during the recharge phase of the El Niño–La Niña cycle. The buildup of warm water in the Tropics before the 1997–98 El Niño is shown to be fed primarily by warm water drawn from the region in the western Pacific within 5°S–15°N. The exchange cycle between the equatorial band and the higher latitudes north of the equator leads the cycle in the south by 6–8 months. These results are found in all three datasets used herein, hydrography, altimetric observations of SSHA, and Sverdrup transports calculated from multiple wind products, which demonstrates the robustness of the results.


2020 ◽  
Author(s):  
Ursula Röhl ◽  
Deborah J Thomas ◽  
Laurel Childress ◽  

<p>As the world’s largest ocean, the Pacific Ocean is intricately linked to major changes in the global climate system. International Ocean Discovery Program (IODP) Expedition 378 is designed to recover Paleogene sedimentary sections in the South Pacific to reconstruct key changes in oceanic and atmospheric circulation. These cores will provide an unparalleled opportunity to add crucial new data and geographic coverage to existing reconstructions of Paleogene climate and as part of a major regional slate of expeditions in the Southern Ocean to fill a critical need for high-latitude climate reconstructions. Appropriate high-latitude records are unobtainable in the Northern Hemisphere of the Pacific Ocean.</p><p>The drilling strategy included a transect of sites strategically positioned in the South Pacific to recover Paleogene carbonates buried under red clay sequences at present latitudes of 40°–52°S in 4650 – 5075 meters of water depth. Due to technical issues we no longer will be able to reach the deeper sites. Therefore, the focus of Expedition 378 will be now to obtain a continuous sedimentary record of a previously single hole, rotary-drilled, spot-cored, classic Cenozoic high-latitude DSDP Site 277 and provide a crucial, multiple hole, mostly APC-cored, continuous record of the intermediate-depth Subantarctic South Pacific Ocean from the Latest Cretaceous to late Oligocene.</p>


2004 ◽  
Vol 1 (6) ◽  
pp. 8-11 ◽  
Author(s):  
Udgardo Juan L. Tolentino

The Philippines, known as the Pearl of the Orient, is an archipelago of 7107 islands, bounded on the west by the South China Sea, on the east by the Pacific Ocean, on the south by the Sulu and Celebes Sea, and on the north by the Bashi Channel. The northernmost islands are about 240 km south of Taiwan and the southernmost islands approximately 24 km from Borneo. The country has a total land area of some 300 000 km2. It is divided into three geographical areas: Luzon, Visayas and Mindanao. It has 17 regions, 79 provinces, 115 cities, 1495 municipalities and 41 956 barangays (the smallest geographic and political unit). It has over 100 ethnic groups and a myriad of foreign influences (including Malay, Chinese, Spanish and American).


1986 ◽  
Vol 1 (20) ◽  
pp. 145
Author(s):  
H. Kohno ◽  
T. Uda ◽  
Y. Yabusaki

On the Fuji Coast 15 detached breakwaters and 17 wave dissipating breakwaters have been constructed to prevent beach erosion. By virtue of the construction of the breakwaters the retreat rate of the shoreline position has decreased. However a large number of concrete blocks have been scattered due to waves. This study investigates the actual circumstances on the scattering of the concrete armour units of the detached breakwaters through the field observations on the Fuji Coast located in Suruga Bay facing the Pacific Ocean. The change rate of the plane area of the breakwater is examined from the aerial photographs, and the relationships among the parameter, the depth at the offshore foot of the breakwater and the number of the removed concrete armour units are investigated.


Zootaxa ◽  
2021 ◽  
Vol 5051 (1) ◽  
pp. 41-67
Author(s):  
SUPAWADEE CHULLASORN ◽  
PAWANA KANGTIA ◽  
SUNG JOON SONG ◽  
JONG SEONG KHIM

Two new species of the family Harpacticidae Dana, 1846, Tigriopus namsaiensis sp. nov. and T. wannapaensis sp. nov. were found in algal washings at Namsai and Wannapa beaches in Chonburi Province, Thailand. There are currently 14 known species in the genus, two of which, T. thailandensis Chullasorn, Ivanenko, Dahms, Kangtia & Yang, 2012 and T. sirindhornae Chullasorn, Dahms & Klangsin, 2013 were also discovered in Thailand. The genus Tigriopus Norman, 1869 has a worldwide distribution with nine species recorded from the Pacific Ocean (seven in the North Pacific and two in the South Pacific), four species from the Atlantic and adjacent seas, two species from the South Indian Ocean, and one species from Antarctica.                 Sexual dimorphism is expressed in the antennule, antenna, P2, P5, P6, and segmentation of the urosome. Tigriopus namsaiensis sp. nov. and T. wannapaensis sp. nov. are closely related to T. thailandensis and T. sirindhornae in sharing the following characters: fewer sensilla on the prosome; antennary exopod with one seta on exp-2; P4 exp-3 with two inner setae; female P5 baseoendopod with five setae; male P2 enp-2 with a seta fused to the segment; and male P5 exopod with five setae.                 Tigriopus namsaiensis sp. nov. closely resembles T. thailandensis, but the new species is characterized by four setae on the maxillulary coxa (three setae in T. thailandensis), the outermost seta on the female P6 is plumose (instead of the middle one), the lateral seta on the apical segment of the antennary exopod is discrete at the base (instead of fused to the segment), and the outermost seta of the male P5 exopod is plumose (instead of spinulose).                 Tigriopus wannapaensis sp. nov. is very closely related to T. sirindhornae, but the new species differs from the latter by the following characteristics: 2-segmented mandibular exopod (3-segmented in T. sirindhornae); five setae on the maxillulary coxa (instead of three); all setae on female P6 are plumose (instead of two plumose and one pinnate); the lateral seta on the apical segment of the antennary exopod is fused to the segment (instead of discrete at the base); and the outermost seta on the male P5 exopod is plumose (instead of spinulose).                 A dichotomous identification key to the 16 valid species of Tigriopus is provided.  


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