Past Sea Levels, Eustasy and Deformation of the Earth

1972 ◽  
Vol 2 (1) ◽  
pp. 1-14 ◽  
Author(s):  
R. I. Walcott
Keyword(s):  
Sea Level ◽  
Late Glacial ◽  
The United States ◽  
Ground Subsidence ◽  
Postglacial Rebound ◽  
Vertical Movements ◽  
Sea Levels ◽  
Atlantic Seaboard ◽  
The Earth ◽  
Change In Mean

Vertical movements of the earth's surface related to postglacial rebound, the eustatic rise in sea level and the elastic deformation of the globe due to melting of late glacial ice sheets are calculated for simplified models of the earth. The movements of the ground are large and require a reevaluation of what is meant by eustatic sea level change. This is defined here as an ocean-wide average change in mean sea level and its measurement requires widely distributed observations weighted according to the areas of oceans they represent. Evidence of a postglacial (6000-0 years BP) relative rise in sea level comes largely from regions affected by ground subsidence related to adjacent upward postglacial rebound movements in deglaciated areas: evidence for a relative fall of sea level comes from coastlines well removed from areas of rebound and which have been affected by a rise of the continental areas through compensation for the eustatic load. It is concluded: (1) no substantial eustatic change of sea level in the past 6,000 years is required to explain postglacial sea levels: (2) in late glacial time the eustatic curve is probably more like the sea level curve of Texas and Mexico than that of the Atlantic seaboard of the United States: (3) that the information of past sea levels, when sufficiently widespread, can provide an important method of studying the deep mechanical structure of the earth.

scholarly journals Economic damages from Hurricane Sandy attributable to sea level rise caused by anthropogenic climate change

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Benjamin H. Strauss ◽  
Philip M. Orton ◽  
Klaus Bittermann ◽  
Maya K. Buchanan ◽  
Daniel M. Gilford ◽  
...  
Keyword(s):  
Climate Change ◽  
Sea Level Rise ◽  
Sea Level ◽  
East Coast ◽  
The United States ◽  
Hurricane Sandy ◽  
Water Levels ◽  
Anthropogenic Climate Change ◽  
Economic Damage ◽  
Sea Levels

AbstractIn 2012, Hurricane Sandy hit the East Coast of the United States, creating widespread coastal flooding and over $60 billion in reported economic damage. The potential influence of climate change on the storm itself has been debated, but sea level rise driven by anthropogenic climate change more clearly contributed to damages. To quantify this effect, here we simulate water levels and damage both as they occurred and as they would have occurred across a range of lower sea levels corresponding to different estimates of attributable sea level rise. We find that approximately $8.1B ($4.7B–$14.0B, 5th–95th percentiles) of Sandy’s damages are attributable to climate-mediated anthropogenic sea level rise, as is extension of the flood area to affect 71 (40–131) thousand additional people. The same general approach demonstrated here may be applied to impact assessments for other past and future coastal storms.

scholarly journals Palaeo-sea-level and palaeo-ice-sheet databases: problems, strategies, and perspectives

2016 ◽  
Vol 12 (4) ◽  
pp. 911-921 ◽  
Author(s):  
André Düsterhus ◽  
Alessio Rovere ◽  
Anders E. Carlson ◽  
Benjamin P. Horton ◽  
Volker Klemann ◽  
...  
Keyword(s):  
Sea Level ◽  
Research Question ◽  
Ice Sheet ◽  
Original Data ◽  
Sea Levels ◽  
The Earth ◽  
Geological Features ◽  
Funding Agencies ◽  
The Creation ◽  
Objective Description

Abstract. Sea-level and ice-sheet databases have driven numerous advances in understanding the Earth system. We describe the challenges and offer best strategies that can be adopted to build self-consistent and standardised databases of geological and geochemical information used to archive palaeo-sea-levels and palaeo-ice-sheets. There are three phases in the development of a database: (i) measurement, (ii) interpretation, and (iii) database creation. Measurement should include the objective description of the position and age of a sample, description of associated geological features, and quantification of uncertainties. Interpretation of the sample may have a subjective component, but it should always include uncertainties and alternative or contrasting interpretations, with any exclusion of existing interpretations requiring a full justification. During the creation of a database, an approach based on accessibility, transparency, trust, availability, continuity, completeness, and communication of content (ATTAC3) must be adopted. It is essential to consider the community that creates and benefits from a database. We conclude that funding agencies should not only consider the creation of original data in specific research-question-oriented projects, but also include the possibility of using part of the funding for IT-related and database creation tasks, which are essential to guarantee accessibility and maintenance of the collected data.

On Rhythms in the History of the Earth

1939 ◽  
Vol 76 (3) ◽  
pp. 116-129 ◽  
Author(s):  
J. H. F. Umbgrove
Keyword(s):  
Sea Level ◽  
World Wide ◽  
Vertical Movements ◽  
The Earth ◽  
History Of ◽  
Possible Cause ◽  
Insight Into ◽  
And Sea Level

Two publications by Grabau, which will be treated in the following pages, have led to the ensuing considerations.In his opinion world-wide advance and retreat of the sea are simply explained by vertical movements of the sea-level. About the possible cause of these movements he makes some very brief remarks, as we shall see later. It is, however, quite possible that the explanation must be sought in simultaneous but opposed movement of continents and sea-level. In trying to obtain an insight into the cause of these movements, rhythms of an entirely different sort come up for discussion, viz. phases of diastrophism and magmatic cycles. And then a further question presents itself: can these different phenomena be connected, and thus give an insight into certain rhythmical processes in the deeper parts of the earth ? I, personally, am convinced that we must answer this question in the affirmative. Stille, Joly, Holmes, and Bucher have reached a similar conclusion by different ways. Meanwhile, the following pages are only intended to shed some light on the different aspects of the problem, and I shall restrict myself to outlining the questions that demand further study.

Nass River on the move: radar facies analysis of glaciofluvial sedimentation and its response to sea-level change in northwestern British Columbia

2006 ◽  
Vol 43 (11) ◽  
pp. 1733-1746 ◽  
Author(s):  
S J McCuaig ◽  
M C Roberts
Keyword(s):  
British Columbia ◽  
Sea Level ◽  
Facies Analysis ◽  
Late Glacial ◽  
Depositional Environments ◽  
Coarse Grained ◽  
Sea Levels ◽  
Stratal Architecture ◽  
Forced Regression ◽  
Radar Facies

The Nass Valley of northwestern British Columbia is a glacial fiord containing extensive glaciomarine and glaciofluvial sediments. Two parallel braidplains, separated by a bedrock ridge, were deposited within the fiord. Mapping of these deposits led to the hypothesis that the braidplains must have terminated at deltas. However, a lack of surface exposures meant that ground-penetrating radar was needed to investigate these deposits. Radar facies analysis aided in the identification of braidplain, braid delta and glaciomarine depositional environments, as well as underlying bedrock. Several deltas graded to different sea levels were discovered, allowing inferences to be made about the relationship of falling sea level to sediment architecture. The upper section of the western braidplain is graded to a sea level of 185 m above sea level (asl), indicating that the proto-Nass River flowed on the western side of the bedrock ridge when the sea was at that level. However, the river moved to the east side of the ridge as sea level fell, depositing the extensive Aiyansh Braidplain – Braid Delta, which is graded to a 152 m sea-level stand. Several other deltas also formed at this sea-level stand. Avulsion occurred and the river flowed on the west side of the ridge again when sea level fell to 134 m asl. The river remained in this position throughout late glacial time and eventually evolved into the modern Nass River. The coarse-grained deposits are indicative of forced regression, with both stepped-top attached and detached stratal architecture present.

scholarly journals Coldspot of Decelerated Sea-Level Rise on the Pacific Coast of North America

2016 ◽  
Vol 35 (3) ◽  
pp. 31-37 ◽  
Author(s):  
Albert Parker
Keyword(s):  
United States ◽  
Sea Level Rise ◽  
Sea Level ◽  
San Francisco ◽  
West Coast ◽  
Average Rate ◽  
The United States ◽  
The West ◽  
Sea Levels

Abstract We show here the presence of significant “coldspot” of sea level rise along the West Coast of the United States and Canada (including Alaska). The 30-years sea level for the area are mostly falling also at subsiding locations as San Francisco and Seattle where subsidence is responsible for a long term positive rate of rise. The 20 long term tide gauges of the area of length exceeding the 60-years length have a naïve average rate of rise −0.729 mm/year in the update 30-Apr-2015, down from −0.624 mm/year in the update 14-Feb-2014. Therefore, along the West Coast of the United States and Canada the sea levels are on average falling, and becoming more and more negative.

scholarly journals A National Study on Protecting Infrastructure and Public Buildings against Sea Level Rise and Storm Surge

2021 ◽  
Author(s):  
Paul Chinowsky ◽  
Jacob Helman
Keyword(s):  
Sea Level Rise ◽  
Sea Level ◽  
Storm Surge ◽  
The United States ◽  
Design Guidelines ◽  
National Study ◽  
Multiple Perspectives ◽  
Sea Levels ◽  
Rising Sea Levels ◽  
The Cost

The national study analyzes sea level rise (SLR) impacts based on 36 different SLR and storm surge scenarios across 5.7 million geographic locations and 3 time periods. Taking an approach based on engineering design guidelines and current cost estimates, the study details projected cost impacts for states, counties, and cities. These impacts are presented from multiple perspectives including total cost, cost per-capita, and cost per-square mile. The purpose of the study is to identify specific locations where infrastructure is vulnerable to rising sea levels. The study finds that Sea Level Rise (SLR) and minimal storm surge is a $400 billion threat to the United States by 2040 that includes a need for at least 50,000 miles of protective barriers. The research is limited in its scope to protecting coastal infrastructure with sea walls. Additional methods exist and may be appropriate in individual situations. The study is original in that it is a national effort to identify infrastructure that is vulnerable as well as the cost associated with protecting this infrastructure.

Holocene sea levels, paleoceanography, and late glacial ice configuration near the Northumberland Strait, Maritime Provinces

1987 ◽  
Vol 24 (4) ◽  
pp. 668-675 ◽  
Author(s):  
David B. Scott ◽  
Franco S. Medioli ◽  
Ann A. L. Miller
Keyword(s):  
Sea Level ◽  
Atlantic Coast ◽  
Late Glacial ◽  
Bay Of Fundy ◽  
Maritime Provinces ◽  
Glacial Ice ◽  
Sea Levels ◽  
Ice Caps ◽  
Present Rate ◽  
Nova Scotian

Work on new cores from old core sites in Baie Verte, New Brunswick, led to the identification of submerged salt-marsh peats, reported earlier as freshwater ones. A comprehensive sea-level curve, between 9 and 15 m below present, is based on marsh foraminiferal assemblages. These data indicate that between 4500 and 5400 BP relative sea-level (RSL) rise was comparatively slow (about 10 cm/100 years); the rate increased dramatically between 4500 and 4000 BP (1 m/100 years) and decreased between 2000 and 4000 BP to its present rate of 15 cm/100 years. We suggest RSL was falling before 5400 BP and that the sequence in our deepest core is similar to some observed in the Bay of Fundy and Nova Scotian Atlantic coast where early RSL fall is documented. To account for this sea-level record and others nearby we suggest that the ice history here is complex, with three separate ice caps thinning towards this area in late glacial times.Earlier work also indicated a number of sediment sequences barren of benthonic foraminifera, suggesting a complex marine–freshwater history for the area. The study of new cores containing the same sequences indicates no barren zones but a simple transgressive sequence with a warm-water calcareous fauna followed by an agglutinated transitional estuarine foraminiferal fauna.

Late Holocene ice-mass changes recorded in a relative sea-level record from Joinville Island, Antarctica

Geology ◽  
2019 ◽  
Vol 47 (11) ◽  
pp. 1064-1068 ◽  
Author(s):  
Julie Zurbuchen ◽  
Alexander R. Simms
Keyword(s):  
Mass Loss ◽  
Sea Level ◽  
Time Scales ◽  
Antarctic Peninsula ◽  
Global Scale ◽  
Relative Sea Level ◽  
Sea Levels ◽  
Beach Ridges ◽  
The Earth ◽  
The Antarctic

Abstract Recent ice-mass loss driven by warming along the Antarctic Peninsula has resulted in rapid changes in uplift rates across the region. Are such events only a function of recent warming? If not, does the Earth response to such events last long enough to be preserved in Holocene records of relative sea level (RSL), and thus have a bearing on global-scale glacial isostatic adjustment (GIA) models (e.g. ICE-6G)? Answering such questions in Antarctica is hindered by the scarcity of RSL reconstructions within the region. Here, a new RSL reconstruction for Antarctica is presented based on beach ridges from Joinville Island on the Antarctic Peninsula. We find that RSL has fallen 4.9 ± 0.58 m over the past 3100 yr, and that the island experienced a significant increase in the rate of RSL fall from 1540 ± 125 cal. (calibrated) yr B.P. to 1320 ± 125 cal. yr B.P. This increase in the rate of RSL fall is likely due to the viscoelastic response of the solid Earth to terrestrial ice-mass loss from the Antarctic Peninsula, similar to the Earth response experienced after ice-mass loss following acceleration of glaciers behind the collapsed Larsen B ice shelf in 2002 C.E. Additionally, slower rates of beach-ridge progradation from 695 ± 190 cal. yr B.P. to 235 ± 175 cal. yr B.P. potentially reflect erosion of beach ridges from a RSL rise induced by a local glacial advance. The rapid response of the Earth to minor ice-mass changes recorded in the RSL record further supports recent assertions of a more responsive Earth to glacial unloading and at time scales relevant for GIA of Holocene and Pleistocene sea levels. Thus, current continental and global GIA models may not accurately capture the ice-mass changes of the Antarctic ice sheets at decadal and centennial time scales.

Now What?

2014 ◽  
Author(s):  
Michael H. Fox
Keyword(s):  
The United States ◽  
The Arctic ◽  
Weather Extremes ◽  
Atmospheric Concentration ◽  
Intergovernmental Panel ◽  
Sea Levels ◽  
The Earth ◽  
The World ◽  
Great Pressure ◽  
Carbon Dioxide Co2

Time is running short! When the Intergovernmental Panel on Climate Change (IPCC) published its first scientific report in 1990 on the possibility of humancaused global warming, the atmospheric concentration of carbon dioxide (CO2 ) was 354 ppm. When I began writing this book about four years ago, the concentration of CO2 was 387 ppm. It is now 397 ppm and rising. In spite of Kyoto, in spite of Copenhagen and Cancun, atmospheric CO2 continues its inexorable upward path. And the earth continues to warm. The United States and the world are not yet serious about changing policies to stop this spiral. Too many politicians and others have their heads buried in the sand and refuse to acknowledge the continuing deluge of data showing that the world is indeed warming. 2010 was the warmest year—and the decade from 2000 to 2010 was the warmest decade—for at least the last 100,000 years. A serious debate is ongoing among geologists to decide if the earth has formally passed out of the Holocene epoch of the last 12,000 years into the Anthropocene epoch, in which 7 billion humans are the primary factor driving climate. Sea levels continue to rise, the oceans are acidifying, glaciers and ice sheets continue to melt, the Arctic will likely be ice-free during the summer sometime this century, and weather extremes have become commonplace around the earth. Plant and animal species are migrating to higher latitudes at 17 kilometers per decade on average, and alpine species are moving to higher altitudes at 11 meters every decade. Changes like this have occurred in the past, but over time spans of thousands to tens of thousands of years, giving species time to adapt. There are those who argue that species have always had to adapt to a changing climate or die and therefore they will handle the current changes. While there is some truth to that, it ignores the fact that many species are already under great pressure from the impact of humans on habitat.

Rates of subsidence and relative sea level rise in the Hawaii Islands

2016 ◽  
Vol 5 (4) ◽  
Author(s):  
Albert Parker
Keyword(s):  
United States ◽  
Global Warming ◽  
Sea Level ◽  
Coastal Erosion ◽  
Hot Spot ◽  
The United States ◽  
Beach Erosion ◽  
Sea Levels ◽  
The Pacific ◽  
Volcanic Islands

AbstractThe major cause of the Hawaiian Islands coastal erosion is shown to be not global warming, but the sinking of the volcanic islands. The geologic “circle-of-life” beyond the Hawaiian hot spot is the true explanation of the beach erosion. The sea levels are slow rising and not accelerating worldwide as well as in the United States. In the specific of the Hawaii Islands, they have been decelerating over the last 3 decades because of the phasing of the multi-decadal oscillations for this area of the Pacific. There is therefore no evidence coastal erosion will double in the Hawaii by 2050 because of global warming.

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