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The article presents a study examining the late-Holocene Epoch sea level based on a reconstruction from a salt marsh in the Malltraeth estuary in North Wales. Information is provided on how the research can inform modeling of past and future relative sea-level changes in the British Isles.

Abstract Grain size, clay mineralogy, 87Sr/86Sr, εNd, and AMS14C analyses of deep-sea sediments cored in the central Bay of Bengal are used to reconstruct the evolution of provenances and climate control since the last glacial period. Clay minerals, 87Sr/86Sr ratios and εNd values indicate a mixture of sediment from the Himalaya source, Indian Peninsula and Indo-Burman Ranges/Irrawaddy River. These analyses show that the Himalaya Mountains and Indo-Burman Ranges/Irrawaddy River are the main suppliers before the Holocene period, while the inputs of erosion materials from the Indo-Gangetic floodplain and the Indian Peninsula increase during the Holocene period, accompanied by reduced inputs of the Indo-Burman Ranges and Irrawaddy sediments. The regional "source-sink" process is significantly controlled by the climate. Warm and wet climate conditions and enhanced Indian monsoon intensity during the Holocene period are responsible for the increase of sediment input from the Indo-Gangetic Plain and the Indian Peninsula by improving erosion in the source area, input from the floodplain to the river channel and the intensity of the southwest monsoon current. In contrast, due to the decrease of the northeast monsoon current during the Holocene period, sediment input from the Irrawaddy and Indo-Burman Ranges are constrained. Deposition center transition between the submarine fan and shelf during the last glacial period and the Holocene period occurs in response to the sea level change, which controls the sedimentary mode and thus significantly influences the transportation and deposition processes in the Bay of Bengal (BoB). [ABSTRACT FROM AUTHOR]

The article comments on sea level rise. Topics discussed include the projected variation in global mean sea level (GMSL) increase, the use of tide gauge and satellite altimetry in measuring sea levels, and the concept of local sea level variations. Information on the contribution of melting land-ice in Antarctica and Greenland to sea level rise is also given.

Climate change-induced perturbations in the hydrologic regime are expected to impact biogeochemical processes, including contaminant mobility and cycling. Elevated levels of geogenic and anthropogenic arsenic are found along many coasts around the world, most notably in south and southeast Asia but also in the United States, particularly along the Mid-Atlantic coast. The mechanism by and the extent to which arsenic may be released in contaminated coastal soils due to sea level rise are unknown. Here we show a series of data from a coastal arsenic-contaminated soil exposed to sea and river waters in biogeochemical microcosm reactors across field-validated redox conditions. We find that reducing conditions lead to arsenic release from historically contaminated coastal soils through reductive dissolution of arsenic-bearing mineral oxides in both sea and river water inundations, with less arsenic release from seawater scenarios than river water due to inhibition of oxide dissolution. For the first time, we systematically display gradation of solid phase soil-arsenic speciation across defined redox windows from reducing to oxidizing conditions in natural waters by combining biogeochemical microcosm experiments and X-ray absorption spectroscopy. Our results demonstrate the threat of sea level rise stands to impact arsenic release from contaminated coastal soils by changing redox conditions. [ABSTRACT FROM AUTHOR]

Recent eustatic sea level rise (SLR) is one of the most striking manifestations of recent climate change as it directly impacts coastal activities and ecosystems. Although global SLR is well-known, local values differ due to vertical land motion, and changes in atmospheric pressure, ocean currents and temperatures. Although a reliable estimation of local SLR trends is needed to assess coastal zone vulnerabilities and plan adaptation strategies, instrumental records are usually short or sparse, especially in developing countries. Here we show that 210 Pb-dated sedimentary records from mangrove saltmarshes can provide useful decadal records of local SLR trends. We quantified sediment accretion rates in sediment cores from remote mangrove saltmarshes of the Yucatan Peninsula. Best SLR records were observed for cores collected near mean sea level (MSL). During most of the XX century the SLR rate ranged from 1-2 mm yr -1 , increased to a maximum of 4.5 ± 0.6 mm yr -1 and the acceleration was 0.13 mm yr -2 . Assuming either a constant SLR rate or acceleration, by the end of this century MSL level will be 39 cm or 91 cm above the present value. Both coastal infrastructures and ecosystems will be negatively affected by SLR and society will need to adapt relatively fast to the new conditions. [ABSTRACT FROM AUTHOR]

In order to understand the influence of sea level rise (SLR) on the tide, waves and sediment transport on a regional scale, and more importantly the implication of such changes on coastal engineering practice, three estuaries in north-west England, Mersey, Dee and Ribble, were chosen for detailed study using a numerical morphological model system, Telemac. The numerical model was calibrated against available field measurements on both hydrodynamics and sediment transport. Simulations were first carried out for a given 0·5 m SLR condition. The overall impact of the SLR on tidal range and flow current speed was found to be small. It is clear that the surf zone is shifted inshore due to the increased water depth. Moreover, changes to the sediment transport within each estuary are complex due to specific interplays between hydrodynamics and tidal flats. Finally, a modified 'parallel online' approach with variable morphological factors was employed for a 90-year simulation with constant SLR rate, together with an 'input-reduction' method. The overall morphological evolution under a constant SLR rate was investigated, which clearly suggests that the most commonly occurring waves tend to bring sediment onshore and into estuaries by eroding outer estuaries and channels, but storm-driving waves tend to erode inner estuaries. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of climate change on the world's oceans. It cites a report compiled for this journal by Benjamin Hamlington, an ocean scientist at NASA's Jet Propulsion Laboratorys, which stated that the faster melting of Greenland's ice has increased the rate of ocean's rise to 4.8 millimeters per year. It is noted that group led by physical oceanographer Sönke Dangendorf has used tide gauge readings that show that seas have risen 20 centimeters since 1900.