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The benefits and problems created by management of shorelines to limit the inevitability of coastal erosion and survival of fixed structures at the shorelines are reviewed. Geologists believe that fixed structures built on coastal area might be devastated by tropical storms, extra tropical storms or rising sea levels.

Coch, N.K., 2020. Inland damage from hurricanes. Journal of Coastal Research, 36(5), 1093–1105. Coconut Creek (Florida), ISSN 0749-0208. Hurricanes result in severe wind and flooding along the coast. In general, their effects decrease in intensity inland. A less well-known feature is that some tropical storms can penetrate deep into the interior and cause severe freshwater flooding and wind destruction far from the coast. Exceptional inland damage can result from a number of meteorological and topographical scenarios. A deteriorating hurricane may merge with a moist extratropical low-pressure system, causing massive rainfall and river flooding (Tropical Storm Agnes in Pennsylvania, 1969). Winds can be channeled through passes on mountainous islands, like Kauai, to cause massive destruction on the lee side (Hurricane Iniki, 1992). Mountains can induce orographic precipitation that can result in massive debris flows (Hurricane Camille in Nelson County, Virginia, 1969). A decaying hurricane can have high convective centers inland that result in localized damage more typical of the hurricane at landfall (Hurricane Hugo, 1989). Finally, northern hurricanes can encounter polar air masses on their left sides as they move inland in the early fall (the New England Hurricane of 1938). While inland intensification is not common, it can occur under certain conditions as outlined in this paper. It is important to consider the possibility of inland intensification in every hurricane. Although the frequency is low, the consequences can be very high. [ABSTRACT FROM AUTHOR]

Coch, N.K., 2019. Forensic analysis of the 1893 "New York City" hurricane: Implications for the future. Journal of Coastal Research, 35(4), 729–736. Coconut Creek (Florida), ISSN 0749-0208. Examination of an offshore-replenished beach in New York City in 1995 revealed that it contained anthropogenic debris from the distant past. Dating of the debris determined that the archeological items were deposited from a category 1 hurricane that made landfall in New York City on the nights of 23–24 August 1893. This "midnight storm" caused great damage in spite of its relatively low category on the Saffir-Simpson scale. A detailed study of the storm was conducted because it was the first hurricane to hit a major metropolitan area with many high-rise buildings. Subsequent discovery of the original weather records from New York City allowed for the re-creation of meteorological conditions in 1893, and they account for the great destruction it caused. The meteorological data were also used to conduct a SLOSH analysis that provided additional information on the storm. These analyses helped to determine why the damage was so high. The results of this study have provided valuable information for damage mitigation in future northern hurricanes. [ABSTRACT FROM AUTHOR]

Coch, N.K., 2019. Sediment facies and dispersal systems in the estuaries of easternmost Long Island, New York, U.S.A. Journal of Coastal Research, 35(1), 165–176. Coconut Creek (Florida), ISSN 0749-0208. A multidecadal study of the estuarine systems of easternmost Long Island, New York, U.S.A. has provided detailed data on sediment facies, structures, and sediment dispersal patterns in this important estuarine–oceanic system. In addition, new data are presented on the unique morphology, sediment type, and distribution and geological history of the three deep channels connecting Block Island Sound and Long Island systems. Detailed sediment facies mapping has delineated six separate sediment dispersal systems in the study area. [ABSTRACT FROM AUTHOR]

Coch, N.K.; Lenna, M., and Deely, A., 2017. Anthropogenic land changes and sedimentation response in the tidal straits of New York City. The sand and gravel mixtures found in the northern part of New York Harbor ( i.e. Upper Bay) have long been attributed to the transport of coarse-grained sediments into the harbor from the Atlantic. A recent sedimentological study of New York Harbor suggested that the origin of this facies may have been from the East and Harlem rivers. Today, there are no tributaries supplying sediment to the East River-Harlem River system. A review of oceanographic and historical data and a detailed bottom sediment mapping program has established the historical drainage changes in New York City and the effect on sediments supplied to the East River-Harlem River system. Before the 18th Century, the East River and the Harlem River were major suppliers of coarse sediments to New York Harbor. However, development and filling in of almost all of New York's tributaries have cut off this sediment supply. The decrease in surface drainage has increased the danger of New York City flooding from Nor'easters and hurricanes. Finally, this research has shown that there are three, not two, sources of sediment for New York Harbor. [ABSTRACT FROM AUTHOR]

Coch, N.K., 2016. Sediment dynamics in the Upper and Lower Bays of New York Harbor. A long-term geologic and oceanographic study has provided the first holistic picture of sediment dynamics in the estuaries of SW New York state. Oceanographic data indicates that the east (Brooklyn) part of the Upper Bay is flood dominant, while the western (Staten Island) side is ebb-dominant. Bedform analysis indicates a net northerly (flood) orientation on the eastern side of the Lower Bay. The west side, in contrast, has fine sediment similar to that supplied by the Hudson River to the Upper Bay. The numerous sand borrow pits on the nearshore shelf also reflect a difference in net flow. The eastern pits are filled with shelf sands while the western ones are filled with mixtures of fine Hudson derived sediments and shelf sands. These patterns suggest flood dominant transport of shelf sands from the Lower Bay into the Upper Bay and ebb dominant supply of Hudson-derived fine material into the Lower Bay on the western side. The shelf and Hudson River Estuary are not the only suppliers of sediment to New York Harbor. The East River and Harlem Rivers have supplied significant amounts of coarse sediment to the northern part of the Upper Bay. This continued until massive stream changes in the 19th Century cut off sediment supply. The East and Harlem River sediments were deposited in a delta extending south and west of the Battery in Manhattan. Part of the relict East River material is now being reworked and moved northward by flood dominant nontidal flow along the eastern shore of the Hudson. [ABSTRACT FROM AUTHOR]

Coch, N.K., 2015. Unique vulnerability of the New York-New Jersey Metropolitan Area to hurricane destruction. Hurricanes making landfall in the New York-New Jersey Metropolitan Area (NYNJMA) are infrequent, but their effects are considerably greater than those of similar Saffir-Simpson categories in the South. Hurricanes that caused major damage hit the NYNJMA directly in 1821 and 1893, and the only major (Category 3+) U.S. hurricane to hit several major U.S. urban coastal centers was the Long Island-New England Hurricane of 1938. The destruction resulting from landfall of a northern hurricane is greater that of a similar Saffir-Simpson category storm in the South. This damage amplification is the result of both the different characteristics of northern hurricanes and the unique geographic, geologic, oceanographic, and demographic characteristics in the northeast United States. Northern hurricanes move two to three times faster, have enlarged wind fields, and have a mostly coast-normal track that carries their more devastating right side hundreds of kilometers inland. A review of historical hurricane landfalls in the NYNJMA shows how they greatly amplify the damage from hurricane winds, storm surge, and freshwater flooding. Past hurricane landfalls caused great damage when the region was far less settled and developed than today. The NYNJMA is now the most densely settled and developed hurricane-prone urban coastal region in the world, and hurricane landfall will result in damage and economic dislocation that will have national and international economic, as well as other, consequences. [ABSTRACT FROM AUTHOR]

South Florida, United States, is an ideal place for conveniently studying modern carbonate environments and their fossil equivalents in close proximity. It is the only place where such field studies can be carried out with the excellent logistical support available in a major metropolitan area (Miami). Consequently, south Florida has been used extensively for training petroleum geologists as well as providing reef and quarry trips of short duration for geology classes. However, south Florida can also be used to study geomorphic features; biogenic and clastic sedimentology in fresh, brackish, and saline environments; and stratigraphie studies which correlate widely-spaced rock outcrops. In addition, many aspects of environmental geology, including groundwater, water pollution, ecological changes accompanying development, and the effects of hurricanes, can be studied here. This holistic approach was used in a 3 week laboratory and field course first offered in the summer of 1985. The area has been visited several times since then, and the places and features described in this paper are accurate as of February 2012. A uniformitarian approach was used, in which students studied rock outcrops and then examined the present-day depositional equivalent of each facies by snorkeling over modern reef tracts in the Florida Keys. Outcrops of Pleistocene rock units were examined from Miami southward through the Florida Keys. Students utilized the outcrop data, along with published data and their own observations of reef complexes, to make a regional stratigraphie synthesis and paleogeographic reconstruction for the study area. This article describes the course structure, field exercises, and logistics, which can serve as the basis for similar courses or site visits in this area in the future. Additional information is provided so instructors can tailor the course around their available time and financial limitations, anywhere from 3 days to 3 weeks. [ABSTRACT FROM AUTHOR]

The author discusses hurricane flood protection policies for New York City (NYC) in response to the article "The Lessons of Katrina, Learned and Unlearned" by Douglas Hill in a 2012 issue. Topics include the construction of storm surge barriers, sea levels and NYC's topography, and the possibility of evacuating the city in response to flooding.