Louisiana Applied Oil Spill Research and Development Program, OSRAPD Technical Report Series 97-002. Int J Remote Sens 24:741–760īraud DH, Feng W (1998) Semi-automated construction of the Louisiana coastline digital land/water boundary using Landsat Thematic Mapper satellite imagery. Mar Geol 99:67–77īosworth J, Koshimizu T, Acton ST (2003) Multi-resolution segmentation of soil moisture imagery by watershed pyramids with region growing merging. These rates of changes have been significantly altered by the construction of intensive shoreline protective structures built from 1990 to combat areas of rapid erosion at both the Rosetta promontory and Burullus–Baltim headland, ∼15-km length in total.īlodget HW, Taylor PT, Roark JH (1991) Shoreline changes along the Rosetta–Nile Promontory: Monitoring with satellite observations. In contrast areas of shoreline accretion exist within saddles or embayments between the promontories at west Abu Qir Bay (20.04 m/year), Abu Khashaba saddle (16.17 m/year) and Gamasa embayment (20.68 m/year). Maximum shoreline retreat occurs along the Rosetta promontory (−138.52 m/year) and along the central bulge of the delta at Burullus headland (−6.07 m/year). Before protection, results reveal longshore patterns wherein erosion along a coastal stretch gives way to accretion in an adjacent stretch, refining the sub-cells previously identified within the littoral system of the delta. On comparison, rates estimated from three statistical approaches (the end point rate, the Jackknife and a weighted linear regression) at corresponding positions are successfully validated with those measured from ground survey. A digital shoreline analysis software was used to calculate the annual rate of beach changes at 1,432 cross-shore transects prior to (1972–1990) and after protection (1993–2006). Automated waterline positions extracted from Landsat satellite images during this period of time were computer generated. The image data used (MSS, TM and ETM+ sensors) are acquired at unequal intervals between 19, i.e., covering a time span of 34 years. Its unusual shape twists in a circular, counter-clockwise direction.Analyses have been undertaken to examine shoreline positions established from remote sensing data along the northwestern part of the Nile delta from the Abu Qir Bay to Gamasa embayment (∼143 km length). Smithson constructed the 4,500 457-meter (1,500-foot) jetty out of rock and earth. Spiral Jetty is on the northeast shore of the Great Salt Lake, in the U.S. The most famous jetty is probably Spiral Jetty, a large sculpture created by the artist Robert Smithson in 1970. This jetty was renovated in 2006 and is popular with tourists because of the view it offers of Namibias coastline. The Swakopmund jetty in the African country of Namibia was constructed with iron in 1905 in order to protect the towns harbor from gathering too much silt, or sediment. They usually provide safe access to coastal areas. Jetties can be popular tourist attractions. Jetties can also be used to connect the land with deep water farther away from shore for the purposes of docking ships and unloading cargo. Jetties protect the shoreline of a body of water by acting as a barrier against erosion from currents, tides, and waves. Strong river currents or waves from a lake can also erode a coastline. They stretch from the shore into the water.Ĭurrents and tides of an oceancan gradually wash away a beach or other features along the coastline. Jetties are usually made of wood, earth, stone, or concrete. A jetty is a long, narrow structure that protects a coastline from the currents and tides.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |