Measuring Sea Level Rise Along the Coast

Vertical land motion at tide gauges influences sea level rise acceleration; this must be addressed for interpreting reliable sea level projections. In recent years, tide gauge records for the Eastern coast of Korea have revealed rapid increases in sea level rise compared with the global mean. Pohang Tide Gauge Station has shown a +3.1 cm/year sea level rise since 2013. This study aims to estimate the vertical land motion that influences relative sea level rise observations at Pohang by applying a multi-track Persistent Scatter Interferometric Synthetic Aperture Radar (PS-InSAR) time-series analysis to Sentinel-1 SAR data acquired during 2015–2017. The results, which were obtained at a high spatial resolution (10 m), indicate vertical ground motion of −2.55 cm/year at the Pohang Tide Gauge Station; this was validated by data from a collocated global positioning system (GPS) station. The subtraction of InSAR-derived subsidence rates from sea level rise at the Pohang Tide Gauge Station is 6 mm/year; thus, vertical land motion significantly dominates the sea level acceleration. Natural hazards related to the sea level rise are primarily assessed by relative sea level changes obtained from tide gauges; therefore, tide gauge records should be reviewed for rapid vertical land motion along the vulnerable coastal areas.

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Water level changes, subsidence, and sea level rise in the Ganges–Brahmaputra–Meghna delta

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1912921117 ◽

2020 ◽

Vol 117 (4) ◽

pp. 1867-1876 ◽

Cited By ~ 10

Author(s):

Mélanie Becker ◽

Fabrice Papa ◽

Mikhail Karpytchev ◽

Caroline Delebecque ◽

Yann Krien ◽

...

Keyword(s):

Sea Level Rise ◽

Water Level ◽

Sea Level ◽

El Niño ◽

El Nino ◽

Southern Oscillation ◽

Climate Mitigation ◽

Vertical Land Motion ◽

The Ganges ◽

And Sea Level

Being one of the most vulnerable regions in the world, the Ganges–Brahmaputra–Meghna delta presents a major challenge for climate change adaptation of nearly 200 million inhabitants. It is often considered as a delta mostly exposed to sea-level rise and exacerbated by land subsidence, even if the local vertical land movement rates remain uncertain. Here, we reconstruct the water-level (WL) changes over 1968 to 2012, using an unprecedented set of 101 water-level gauges across the delta. Over the last 45 y, WL in the delta increased slightly faster (∼3 mm/y), than global mean sea level (∼2 mm/y). However, from 2005 onward, we observe an acceleration in the WL rise in the west of the delta. The interannual WL fluctuations are strongly modulated by El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) variability, with WL lower than average by 30 to 60 cm during co-occurrent El Niño and positive IOD events and higher-than-average WL, by 16 to 35 cm, during La Niña years. Using satellite altimetry and WL reconstructions, we estimate that the maximum expected rates of delta subsidence during 1993 to 2012 range from 1 to 7 mm/y. By 2100, even under a greenhouse gas emission mitigation scenario (Representative Concentration Pathway [RCP] 4.5), the subsidence could double the projected sea-level rise, making it reach 85 to 140 cm across the delta. This study provides a robust regional estimate of contemporary relative WL changes in the delta induced by continental freshwater dynamics, vertical land motion, and sea-level rise, giving a basis for developing climate mitigation strategies.

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Spatio-temporal decomposition of geophysical signals in North America

10.5194/egusphere-egu2020-16232 ◽

2020 ◽

Author(s):

Aoibheann Brady ◽

Jonathan Rougier ◽

Bramha Dutt Vishwakarma ◽

Yann Ziegler ◽

Richard Westaway ◽

...

Keyword(s):

North America ◽

Sea Level Rise ◽

Sea Level ◽

Global Scale ◽

Bayesian Hierarchical ◽

Isostatic Adjustment ◽

Modelling Framework ◽

Vertical Land Motion ◽

Early Results ◽

Spatio Temporal

Sea level rise is one of the most significant consequences of projected future changes in climate. One factor which influences sea level rise is vertical land motion (VLM) due to glacial isostatic adjustment (GIA), which changes the elevation of the ocean floor. Typically, GIA forward models are used for this purpose, but these are known to vary with the assumptions made about ice loading history and Earth structure. In this study, we implement a Bayesian hierarchical modelling framework to explore a data-driven VLM solution for North America, with the aim of separating out the overall signal into its GIA and hydrology (mass change) components. A Bayesian spatio-temporal model is implemented in INLA using satellite (GRACE) and in-situ (GPS) data as observations.&#160;Under the assumption that GIA varies in space but is constant in time, and that hydrology is both spatially- and temporally-variable, it is possible to separate the contributions of each component with an associated uncertainty level. Early results will be presented. Extensions to the BHM framework to investigate sea level rise at the global scale, such as the inclusion of additional processes and incorporation of increased volumes of data, will be discussed.

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Using subsidence scenarios to assess flood risk to delta cities under future sea level rise.

10.5194/egusphere-egu2020-19378 ◽

2020 ◽

Author(s):

Luke Jackson

Keyword(s):

Ground Water ◽

Sea Level Rise ◽

Sea Level ◽

Damage Model ◽

Water Levels ◽

Policy Intervention ◽

Local Policy ◽

Vertical Land Motion ◽

Number Of Factors ◽

Climate Crisis

City level coastal subsidence can be caused by a number of factors, both natural (e.g. compaction) and anthropogenic (e.g. ground water extraction). Past observations in cities indicates that the rate of subsidence can be altered through policy intervention (e.g. Tokyo's ban on ground water pumping in 1970's). Given vertical land motion is a key component in local sea level projections where subsidence amplifies the onset of future damages, we test the extent to which intervention could reduce risk with a simple city level coastal damage model. We adjust water levels to embed different time dependent subsidence scenarios over the 21st century. We contend that local policy intervention to slow anthropogenic subsidence where possible will slow the onset of damaging sea level rise thus reducing potential coastal damages, and reduce the required increases in future flood protection heights. Performed in tandem with global mitigation efforts, cities currently under major threat may yet survive the climate crisis.

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Sea Level Rise Scenario for 2100 A.D. in the Heritage Site of Pyrgi (Santa Severa, Italy)

10.20944/preprints201910.0202.v1 ◽

2019 ◽

Author(s):

Marco Anzidei ◽

Fawzi Doumaz ◽

Antonio Vecchio ◽

Enrico Serpelloni ◽

Luca Pizzimenti ◽

...

Keyword(s):

High Resolution ◽

Sea Level Rise ◽

Sea Level ◽

Storm Surges ◽

Coastal Zones ◽

Heritage Sites ◽

Historical Structures ◽

Vertical Land Motion ◽

Climatic Scenarios ◽

The Mediterranean

Sea level rise is one of the main factor of risk for the preservation of cultural heritage sites located along the coasts of the Mediterranean basin. Coastal retreat, erosion and storm surges are yet posing serious threats to archaeological and historical structures built along the coastal zones of this region. In order to assess the coastal changes by the end of 2100 under an expected sea level rise of about 1 m, a detailed determination of the current coastline position and the availability of high resolution DSM, is needed. This paper focuses on the use of very high-resolution UAV imagery for the generation of ultra-high resolution mapping of the coastal archaeological area of Pyrgi, near Rome (Italy). The processing of the UAV imagery resulted in the generation of a DSM and an orthophoto, with an accuracy of 1.94 cm/pixel. The integration of topographic data with two sea level rise projections in the IPCC AR5 2.6 and 8.5 climatic scenarios for this area of the Mediterranean, were used to map sea level rise scenarios for 2050 and 2100. The effects of the Vertical Land Motion (VLM) as estimated from two nearby continuous GPS stations located as much as close to the coastline, were included in the analysis. Relative sea level rise projections provide values at 0.30±0.15 cm by 2050 and 0.56±0.22 by 2100, for the IPCC AR5 8.5 scenarios and at 0.13±0.05 cm by 2050 and 0.17±0.22 by 2100, for the IPCC AR5 2.6 scenario. These values of rise will correspond to a potential beach loss between 12.6% and 23.5% in 2100 for RCP 2.6 and 8.5 scenarios, respectively, while during the highest tides the beach will be reduced up to 46.4%. With these sea level rise scenarios, Pyrgi with its nearby Etruscan temples and the medieval castle of Santa Severa will be soon exposed to high risk of marine flooding, especially during storm surges, thus requiring suitable adaptation strategies.

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GEOCENTRIC MEAN SEA LEVEL FIELDS AT THE GERMAN NORTH SEA AND BALTIC COAST

Coastal Engineering Proceedings ◽

10.9753/icce.v36.currents.21 ◽

2018 ◽

pp. 21

Author(s):

Jessica Kelln ◽

SÃ¶nke Dangendorf ◽

JÃ¼rgen Jensen ◽

Justus Patzke ◽

Wolfgang Niemeier ◽

...

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Tide Gauge ◽

Last Deglaciation ◽

Mean Sea Level ◽

Baltic Coast ◽

Vertical Land Motion ◽

Level Information ◽

The Last Deglaciation ◽

Global Mean Sea Level

Global mean sea level has risen over the 20th century (Hay et al. 2015; Dangendorf et al. 2017) and under sustained greenhouse gas emissions it is projected to further accelerate throughout the 21st century (Church et al. 2013) with large spatial variations, significantly threatening coastal communities. Locally the effects of geocentric (sometimes also referred to absolute) sea level rise can further be amplified by vertical land motion (VLM) due to natural adjustments of the solid earth to the melting of the large ice-sheets during the last deglaciation (GIA) or local anthropogenic interventions such as groundwater or gas withdrawal (e.g. SantamarÃa-GÃ³mez et al. 2017). Both, the observed and projected geocentric sea level rise as well as VLM are critically important for coastal planning and engineering, since only their combined effect determines the total threat of coastal flooding at specific locations. Furthermore, due large spatial variability of sea level, information is required not only at isolated tide gauge (TG) locations but also along the coastline stretches in between.

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Is the Risk of Sea Level Rise Capitalized in Residential Real Estate?

Review of Financial Studies ◽

10.1093/rfs/hhz134 ◽

2020 ◽

Vol 33 (3) ◽

pp. 1217-1255 ◽

Cited By ~ 9

Author(s):

Justin Murfin ◽

Matthew Spiegel

Keyword(s):

Real Estate ◽

Sea Level Rise ◽

Sea Level ◽

Residential Real Estate ◽

Cross Sectional ◽

Null Results ◽

Expected Time ◽

Vertical Land Motion ◽

Price Effects ◽

Home Sales

Abstract Using a comprehensive database of coastal home sales merged with data on elevation relative to local tides, we compare prices for houses based on their inundation threshold under projections of sea level rise. The analysis separates the sensitivity of housing to rising seas from other confounding characteristics by exploiting cross-sectional differences in relative sea level rise due to vertical land motion. This provides variation in the expected time to inundation for properties of similar elevation and distance from the coast. In a variety of specifications and test settings, we find precisely estimated null results suggesting limited price effects.

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Sea Level Rise Scenario for 2100 A.D. in the Heritage Site of Pyrgi (Santa Severa, Italy)

Journal of Marine Science and Engineering ◽

10.3390/jmse8020064 ◽

2020 ◽

Vol 8 (2) ◽

pp. 64 ◽

Cited By ~ 3

Author(s):

Marco Anzidei ◽

Fawzi Doumaz ◽

Antonio Vecchio ◽

Enrico Serpelloni ◽

Luca Pizzimenti ◽

...

Keyword(s):

High Resolution ◽

Sea Level Rise ◽

Sea Level ◽

Storm Surges ◽

Coastal Zones ◽

Dune System ◽

Intergovernmental Panel ◽

Historical Structures ◽

Vertical Land Motion ◽

The Mediterranean

Sea level rise is one of the main risk factors for the preservation of cultural heritage sites located along the coasts of the Mediterranean basin. Coastal retreat, erosion, and storm surges are posing serious threats to archaeological and historical structures built along the coastal zones of this region. In order to assess the coastal changes by the end of 2100 under the expected sea level rise of about 1 m, we need a detailed determination of the current coastline position based on high resolution Digital Surface Models (DSM). This paper focuses on the use of very high-resolution Unmanned Aerial Vehicles (UAV) imagery for the generation of ultra-high-resolution mapping of the coastal archaeological area of Pyrgi, Italy, which is located near Rome. The processing of the UAV imagery resulted in the generation of a DSM and an orthophoto with an accuracy of 1.94 cm/pixel. The integration of topographic data with two sea level rise projections in the Intergovernmental Panel on Climate Change (IPCC) AR5 2.6 and 8.5 climatic scenarios for this area of the Mediterranean are used to map sea level rise scenarios for 2050 and 2100. The effects of the Vertical Land Motion (VLM) as estimated from two nearby continuous Global Navigation Satellite System (GNSS) stations located as close as possible to the coastline are included in the analysis. Relative sea level rise projections provide values at 0.30 ± 0.15 cm by 2050 and 0.56 ± 0.22 cm by 2100 for the IPCC AR5 8.5 scenarios and at 0.13 ± 0.05 cm by 2050 and 0.17 ± 0.22 cm by 2100, for the IPCC Fifth Assessment Report (AR5) 2.6 scenario. These values of rise correspond to a potential beach loss between 12.6% and 23.5% in 2100 for Representative Concentration Pathway (RCP) 2.6 and 8.5 scenarios, respectively, while, during the highest tides, the beach will be provisionally reduced by up to 46.4%. In higher sea level positions and storm surge conditions, the expected maximum wave run up for return time of 1 and 100 years is at 3.37 m and 5.76 m, respectively, which is capable to exceed the local dune system. With these sea level rise scenarios, Pyrgi with its nearby Etruscan temples and the medieval castle of Santa Severa will be exposed to high risk of marine flooding, especially during storm surges. Our scenarios show that suitable adaptation and protection strategies are required.

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THE VERTICAL LAND MOTION OF TIDE GAUGE AND ABSOLUTE SEA LEVEL RISE IN BOHAI SEA

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-2-w5-601-2019 ◽

2019 ◽

Vol IV-2/W5 ◽

pp. 601-606

Author(s):

D. Zhou ◽

W. Sun ◽

Y. Fu ◽

X. Zhou

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Bohai Sea ◽

Tide Gauge ◽

Sea Level Change ◽

Tide Gauges ◽

Sea Level Changes ◽

The Bohai Sea ◽

Level Change ◽

Vertical Land Motion

Abstract. The ground vertical movement of the tide gauges around the Bohai sea was firstly analyzed by using the observation data from 2009 to 2017 of the nine co-located GNSS stations. It was found that the change rate of ground vertical motion of four stations was in the same order of magnitude as the sea level change. In particular, the land subsidence rate of BTGU station reaches 11.47&thinsp;mm/yr, which should be paid special attention to in the analysis of sea level change. Then combined with long-term tide gauges and the satellite altimetry results, the sea level changes in the Bohai sea and adjacent waters from 1993 to 2012 were analyzed. The relative and absolute sea level rise rates of the sea area are 3.81&thinsp;mm/yr and 3.61&thinsp;mm/yr, respectively, both are higher than the global average rate of change. At the same time, it is found that the vertical land motion of tide gauge stations is the main factor causing regional differences in relative sea level changes.

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