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Sea level rise (SLR) and storm surge have significant impacts on tourism properties and activities in the low-lying coastal region. Coastal tourism in Zhejiang Province, China, is physically and socioeconomically susceptible to the flood risk posed by accelerated SLR and intensified storm surge. In this paper, within a scenario design of SLR and storm surge, a GIS-based dataset of major coastal tourist attractions in coastal Zhejiang is created to assess their potential flood risk by using a simple inundation model and a risk matrix. It is estimated that only two resorts would be directly flooded by a SLR of 1-2 m, but extensive inundation of coastal tourism communities may occur during low-frequency surges, especially after adding predicted 1-m SLR. The risk assessment further shows that a majority of the exposed sites is subject to moderate and low risk at current state but would be at higher (moderate and high)-risk categories in the future. In the long term, a combination of adaption measures is presented for policy-makers and other stakeholders for sustainable flood risk management in coastal tourism destinations. [ABSTRACT FROM AUTHOR]

Sea-level rise as a result of climate change increases inundation and erosion, which are affected by a complex interplay of physical environmental parameters at the coast. China's coast is vulnerable to accelerated sea-level rise and associated coastal flooding because of physical and socio-economical factors such as its low topography, highly developed economy, and highly dense population. To identify vulnerable sections of the coast, this paper presents a national assessment of the vulnerability of the Chinese coast using 8 physical variables: sea-level rise, coastal geomorphology, elevation, slope, shoreline erosion, land use, mean tide range, and mean wave height. A coastal vulnerability index was calculated by integrating the differentially weighted rank values of the 8 variables, based on which the coastline is segmented into 4 classes. The results show that 3% of the 18,000-km-long Chinese coast is very highly vulnerable, 29% is highly vulnerable, 58% is moderately vulnerable, and 10% is in the low-vulnerable class. Findings further reveal that large amounts of land and population will be vulnerable to inundation by coastal flooding from sea level rise and storm surge. Finally, some suggestions are presented for decision makers and other concerned stakeholders to develop appropriate coastal zone management and mitigation measures. [ABSTRACT FROM AUTHOR]

Land subsidence is impacting large populations in coastal Asia via relative sea-level rise (RSLR). Here we assesses these risks and possible response strategies for China, including estimates of present rates of RSLR, flood exposure and risk to 2050. In 2015, each Chinese coastal resident experienced on average RSLR of 11 to 20 mm/yr. This is 3 to 5 times higher than climate-induced SLR, reflecting that people are concentrated in subsiding locations. In 2050, assuming these subsidence rates continue, land area, population and assets exposed to the 100-year coastal flood event is 20%-39%, 17%-37% and 18%-39% higher than assuming climate change alone, respectively. Realistic subsidence control measures can avoid up to two thirds of this additional growth in exposure, with adaptation required to address the residual. This analysis emphasizes subsidence as a RSLR hazard in China that requires a broad-scale policy response, utilizing subsidence control combined with coastal adaptation. Chinese coastal populations are concentrated in subsiding locations, and also subject to sea-level rise. Here the authors find that more areas, population and assets are exposed to coastal flooding by 2050 but realistic subsidence control measures can avoid additional risks. [ABSTRACT FROM AUTHOR]

The Early-Middle Permian δ13Ccarb variations are recorded by the marine carbonates of the Luduba section in the northern margin of the South China Block. The investigated interval (~ 300 m) spans the Chihsia and Maokou formations. Preservation of the investigated micritic carbonates was evaluated by multiple petrographic and geochemical screening tools. The δ13Ccarb and δ18O values of near-primary micrites range from 2.3 to 5.0‰ (VPDB) and from − 6.4 to − 3.4‰ (VPDB), respectively, showing insignificant correlation (R2 = 0.13). Similarly, the Mn/Sr ratios show insignificant correlation with δ13Ccarb or δ18O ratios. In addition, the Al and Sr concentrations exhibit insignificant correlation, which suggests preservation of at least near-primary δ13Ccarb signatures that can be utilized to construct a reliable C-isotope profile of the equatorial eastern Paleo-Tethys for global correlations. The C-isotope profile exhibits distinct short-time negative shifts superimposed on the general long-term trend of increase in δ13Ccarb values. The long-term trend likely reflects a consistent global sea-level rise during the Early Guadalupian, which was associated with one of the largest Permian transgressions. The general sea-level rise was disrupted by few minor short-term sea-level low-stands associated with negative δ13Ccarb shifts (~ 1–2 ‰) on the C-isotope profile, which are associated with similar minor positive 87Sr/86Sr shifts (~ 0.0005 each) on the Sr isotope profile and with Al enrichment, possibly caused by the combination of global eustasy and regional tectonics in South China. Two negative δ13Ccarb shifts have been recorded in the lower and upper Chihsia Formation that can be correlated with the Early Kungurian and the Kungurian/Roadian boundary, respectively. Also, the Maokou Formation records a middle negative shift that inferred correlates with the Early Wordian. These three negative δ13Ccarb shifts are globally comparable with those documented by both the eastern Paleo-Tethys and western Panthalassa Early-Middle Permian sedimentary records and can be utilized as chemostratigraphic markers. The general increase in the δ13Ccarb values peaks at ~ 5 ‰ near the top of the Maokou Formation that resembles the Kamura event recorded in Tethy but there are issues with the origin and timing of this positive δ13Ccarb excursion. The petrological characteristics of the Luduba section carbonates support the suggested scenario of the general long-term trend of sea-level rise. [ABSTRACT FROM AUTHOR]

Shanghai is a low-lying city (3-4 m elevation) surrounded on three sides by the East China Sea, the Yangtze River Estuary, and Hangzhou Bay. With a history of rapid changes in sea level and land subsidence, Shanghai is often plagued by extreme typhoon storm surges. The interaction of sea level rise, land subsidence, and storm surges may lead to more complex, variable, and abrupt disasters. In this paper, we used MIKE 21 models to simulate the combined effect of this disaster chain in Shanghai. Projections indicate that the sea level will rise 86.6 mm, 185.6 mm, and 433.1 mm by 2030, 2050, and 2100, respectively. Anthropogenic subsidence is a serious problem. The maximum annual subsidence rate is 24.12 mm/year. By 2100, half of Shanghai is projected to be flooded, and 46 % of the seawalls and levees are projected to be overtopped. The risk of flooding is closely related to the impact of land subsidence on the height of existing seawalls and levees. Land subsidence increases the need for flood control measures in Shanghai. [ABSTRACT FROM AUTHOR]

The present analysis has revealed that both the altimetry and tide gauge records show a prominent sea level rise from 1993 to 2016 in the coastal seas east of China, including Bohai, Yellow Sea, and East China Sea (BYECS). The regional mean sea level rise rate for the BYECS continental shelf area is ~ 3.2 mm/year, which is close to the global mean (2.9 mm/year). Besides the rising trend, the BYECS sea level anomaly (SLA) also shows obvious interannual and decadal oscillation. It is found that the mid-latitude westerlies, rather than the steric height variability, are responsible for these oscillations. By analyzing the 67-year (1950–2016) hindcast outputs from an eddy-resolving ocean general circulation model, a 14.2 years decadal period is found to dominate the BYECS SLA variability, and the decadal oscillation is positively correlated with the North Pacific Gyre Oscillation (NPGO). The composite analysis and causality analysis demonstrate that during the positive phase of the NPGO, the mid-latitude westerlies decrease and a positive wind stress curl anomaly at the same latitude of the East China Sea's Kuroshio occurs to the south of the westerlies. Consequently, the Kuroshio Current volume transport and sea surface height difference between the two sides of the Kuroshio decrease, that is, the sea level in the BYECS rises. [ABSTRACT FROM AUTHOR]

Against a background of climate change, Macau is very exposed to sea level rise (SLR) because of its low elevation, small size, and ongoing land reclamation. Therefore, we evaluate sea level changes in Macau, both historical and, especially, possible future scenarios, aiming to provide knowledge and a framework to help accommodate and protect against future SLR. Sea level in Macau is now rising at an accelerated rate: 1.35 mm yr over 1925-2010 and jumping to 4.2 mm yr over 1970-2010, which outpaces the rise in global mean sea level. In addition, vertical land movement in Macau contributes little to local sea level change. In the future, the rate of SLR in Macau will be about 20% higher than the global average, as a consequence of a greater local warming tendency and strengthened northward winds. Specifically, the sea level is projected to rise 8-12, 22-51 and 35-118 cm by 2020, 2060 and 2100, respectively, depending on the emissions scenario and climate sensitivity. Under the +8.5 W m Representative Concentration Pathway (RCP8.5) scenario the increase in sea level by 2100 will reach 65-118 cm-double that under RCP2.6. Moreover, the SLR will accelerate under RCP6.0 and RCP8.5, while remaining at a moderate and steady rate under RCP4.5 and RCP2.6. The key source of uncertainty stems from the emissions scenario and climate sensitivity, among which the discrepancies in SLR are small during the first half of the 21st century but begin to diverge thereafter. [ABSTRACT FROM AUTHOR]