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Previous studies suggested that the increase in surface chlorophyll a (Chl a) is due to nutrient upwelling or to the upward mixing of the subsurface Chl a maximum layer under the influence of tropical cyclones, while often ignoring the influence of the subsurface Chl a minimum layer and horizontal advection on Chl a. In this study, we show the important roles of the upward mixing of the subsurface Chl a minimum layer, horizontal advection, as well as the upwelling of the subsurface Chl a maximum layer, taking a looping super typhoon "Saola" in the northwest Pacific in August 2023 as an example. The temporal and spatial changes of Chl a and its physical properties were investigated by combining satellite, Argo, reanalysis, and model data. The results indicate that the combined effects of the upwelling of the subsurface Chl a maximum layer caused by wind stress curls and concurrent near‐surface wind mixing were responsible for the surface Chl a increase in the looping area during the typhoon, while the 13% increase in the depth‐integrated Chl a after the typhoon is mainly due to the nutrients brought by upwelling and subsequent biochemical processes. In the edge area affected by the typhoon, the surface Chl a decrease during the typhoon was mainly due to the upward mixing of the subsurface Chl a minimum layer (the effect of upwelling in this area is relatively weak). Furthermore, the horizontal advection led to a continuous surface Chl a decrease in the edge area after the typhoon. These findings could enhance understanding of Chl a dynamics post‐tropical cyclones, aiding marine ecosystem prediction. [ABSTRACT FROM AUTHOR]

To reduce the environmental damage caused by waste rubber, crumb rubber concrete (CRC) was prepared by replacing some fine aggregates with crumb rubber. The effects of elevated temperature as well as crumb rubber content on the mechanical properties of the prepared CRC were studied. The crumb rubber contents were 0%, 10%, and 20%, while CRC was subjected to atmospheric temperatures (AT) of 300 °C, 500 °C, and 700 °C. The concrete without crumb rubber content was used as the control group at the atmospheric temperature. The mass loss, thermal conductivity characteristics, compressive strength, splitting tensile strength, axial compressive strength, elastic modulus, and stress-strain characteristics of CRC at elevated temperatures were studied. The experimental results show that: (1) With the increase in crumb rubber content and temperature, the cracks on the surface of the specimen gradually widen while the mass loss of the specimen increases. (2) With the increase in crumb rubber content and temperature, the cube compressive strength, splitting tensile strength, axial compressive strength, and elastic modulus of CRC decrease, yet the plastic failure characteristics of CRC are more obvious. (3) The influences of elevated temperature on strength and elastic modulus are as follows: splitting tensile strength > elastic modulus > axial compressive strength > cubic compressive strength. (4) With the increase in temperature, the stress-strain curve of the CRC tends to flatten, the peak stress decreases, and the corresponding peak strain significantly increases. With the increase in crumb rubber content, there is a great decrease in peak stress, yet the corresponding peak strain is basically the same. The use of CRC can be prioritized in applications that increase toughness rather than strength. [ABSTRACT FROM AUTHOR]

The existing operational storm surge model for the Canadian Pacific coast is barotropic without coupling with tides. Here a baroclinic ocean model, which includes tides, storm surges, intra‐seasonal, seasonal, and interannual variations, is developed to reproduce coastal sea levels in the northeast Pacific from 1993 to 2020. The model results are validated against observations at tide‐gauge sites, demonstrating overall good skills for tides and non‐tidal sea levels. The Gumbel distribution is applied to derive extreme sea levels from hourly sea level anomalies. The model‐based extreme sea levels agree approximately with the observation‐based ones. For the 100‐year return period, modeled total extreme sea levels range from 2.14 m at Victoria Harbour to 4.43 m at Queen Charlotte City, and modeled non‐tidal extreme sea levels from 1.02 m at Bella Bella to 1.78 m at Queen Charlotte City. On average, the model‐based values underestimate the 100‐year return level by 0.18 m for total extreme sea levels and by 0.23 m for non‐tidal extreme sea levels. Both the model‐ and observation‐based results reveal that the storm surge at periods less than 10 d accounts for 60% of the 100‐year non‐tidal extreme sea level, and the intra‐seasonal, seasonal, and interannual variations account for 40% of it. The present study improves coastal sea level modeling and model‐based extreme level estimates. Moreover, this study also demonstrates for the first time that the intra‐seasonal to interannual changes contribute substantially to extreme sea levels and that El Niño can enhance this contribution on the Canadian Pacific coast. Plain Language Summary: It is commonly recognized that storm surges, in addition to tides, are the dominant contributor to extreme coastal sea levels. Here an ocean circulation model for the northeast Pacific was developed to compute coastal sea levels from 1993 to 2020. The model results were compared with tide‐gauge data, demonstrating overall good agreement for both tides and non‐tidal sea levels. The extreme sea levels based on the model results agree approximately with the values based on tide‐gauge measurements. It has been found that overall the intra‐seasonal to interannual changes contribute substantially to extreme sea levels, and El Niño can enhance this contribution on the Canadian Pacific coast. Key Points: A baroclinic ocean model in the Northeast Pacific has been developed, improving the coastal sea level simulationThe intra‐seasonal to interannual variations contribute as much as 40% to the non‐tidal 100‐year extreme sea levelsEl Niño can enhance the contribution of intra‐seasonal to interannual variations [ABSTRACT FROM AUTHOR]

In this study, we propose a method for wind speed retrieval using a random forest (RF) algorithm for Cyclone Global Navigation Satellite System (CYGNSS) data. We first compared CYGNSS data with soil moisture active passive (SMAP) data and found a certain deviation in the CYGNSS “young sea, limited fetch” (YSLF) data product for high winds. Then, we used SMAP as the “ground truth” to train an RF model and applied it to the wind speed retrieval of CYGNSS data. The experimental results show that using the RF algorithm for wind speed retrieval can eliminate noise in the CYGNSS YSLF wind speed data and improve retrieval accuracy. In addition, we explored the impact of different input parameter combinations on model performance and found that using an 11-parameter model in CYGNSS wind speed retrieval can achieve optimal performance. This can provide a valuable reference for rapid near-real-time retrieval of tropical cyclones using CYGNSS. [ABSTRACT FROM AUTHOR]

Inthis study, remote sensing measurements were utilized to examine the characteristics of storm surges and sea surface cooling in Chinese coastal waters caused by typhoons. Altimetric data from satellite altimeters were used to determine the magnitude, cross-shelf decaying scale, and propagating speed of storm surges from typhoons. The results were in agreement with estimates obtained from a theoretical model and tide gauge data, showing that the two storm surges propagated as continental shelf waves along the southeastern coast of China. The sea surface cooling, driven by Typhoons 1319Usagi and 1323Fitow, was analyzed using the remote sensing sea surface temperature product, named the global 1 km sea surface temperature (G1SST) dataset, revealing a considerable decrease in the temperature, with the largest decrease reaching 4.5 °C after the passage of 1319Usagi, in line with buoy estimates of 4.6 °C. It was found that 1323Fitow and 1324Danas jointly impacted the southeastern coast of China, resulting in a significant temperature drop of 4.0 °C. Our study shows that incorporating remotely sensed measurements into the study of oceanic responses to typhoons has significant benefits and complements the traditional tide gauge network and buoy data. [ABSTRACT FROM AUTHOR]

Underground pipelines are vital parts to urban water supply, gas supply, and other lifeline systems, affecting the sustainable development of cities to a great extent. The pipeline joint, which is a weak link, may be seriously damaged during natural disasters such as earthquakes. The failure of pipe joints can cause leakage accidents, resulting in system failure and interruption, and even some secondary disasters. Herein, based on uniaxial and plane tensile test results of a T-rubber gasket material, the assembly process and sealing performance of a T-rubber gasket joint of a ductile iron pipe are numerically simulated using the Ogden third-order strain energy density function to fit the material constant. The simulation accounts for severe nonlinearities, including large deformations, hyperelasticity, and complex contacts. The effects of the assembly friction coefficient, assembly depth, and radial clearance deviation of the socket and spigot on the seal contact pressure are analyzed. The results suggest that the entire history of the deformation and stress variations during assembly can be clearly visualized and accurately calculated. For the different friction coefficients, the assembly depth corresponding to the sliding friction condition of the spigot pipe was 74 mm, while the minimum pushing force required to assemble the T-rubber gasket joint of a DN300 ductile iron pipe was 6.8 kN at the ideal situation with a friction coefficient of 0. The effective contact pressure of the rubber gasket seepage surface under various operating conditions is much higher than the normal pressure of municipal pipelines, thus indicating that the rubber gasket joint exhibits the ideal sealing performance. Furthermore, a certain deviation, which is about 20 mm, is allowed for the assembly depth of the rubber gasket joint such that the axial displacement of the pipe joint can be adapted under an earthquake or ground displacement. [ABSTRACT FROM AUTHOR]

In this paper, engineered cementitious composites (ECCs) were prepared with desert sand instead of ordinary sand, and the toughness properties of the ECCs were studied. The particle size of the desert sand was 0.075–0.3 mm, which is defined as ultrafine sand. The ordinary sand was sieved into one control group with a size of 0.075–0.3 mm and three other reference groups. Together with the desert sand group, a total of five groups of ECC specimens were created. Through a uniaxial tensile test, three-point bending test and single-seam tensile test on the ECC specimens, the influence of aggregate particle size and sand type on the ECC tensile strength, deformation capacity, initial crack strength, cement-matrix-fracture toughness, multiple cracking characteristics and strain-hardening properties were studied. The experimental results show that the 28d tensile strain of the four groups of the ordinary sand specimens was 8.13%, 4.37%, 4.51% and 4.23%, respectively, which exceeded 2% and satisfied the requirements for the minimum strain of the ECCs. It is easier to achieve the ECC strain hardening with sand with a fine particle size; thus, a particle size below 0.3 mm is preferred when preparing the ECCs to achieve a high toughness. The multiple cracking performance (MCP) and the pseudostrain hardening (PSH) of desert sand and ordinary sand with a 0.075–0.3 mm grain size were 2.88 and 2.33, and 8.76 and 8.17, respectively, all of which meet the strength criteria and energy criteria and have similar properties. The tensile strength and tensile deformation of the desert sand group were 4.97 MPa and 6.78%, respectively, and the deformation capacity and strain–strengthening performance were outstanding. It is verified that it is feasible to use desert sand instead of ordinary sand to prepare the ECCs. [ABSTRACT FROM AUTHOR]

Haiyang-2 scatterometers (HY-2A/B/C/D) have limitations in high wind speed retrieval due to the complexity of the remote sensing mechanism and the influence of rainfall on the radar cross section under the conditions of tropical cyclones. In this study, we focus on the evaluation of Chinese scatterometer operational wind products from HY-2B/C/D over the period from July 2019 to December 2021. HY-2B/C/D scatterometer wind products are collocated with SMAP (Soil Moisture Active Passive) L-band radiometer remotely sensed measurements. The results show that the underestimation of high wind speed occurs in the HY-2B/C/D wind speed products. The machine learning algorithms are explored to improve this underestimation issue, including the back propagation neural network (BP-NN), K-nearest neighbor (KNN), support vector machine (SVM), decision tree (DT), random forest (RF), and Bayesian ridge (BR) regression algorithms. Comparisons show that the BP-NN algorithm shows the best performance with a small RMSE (root-mean-square error) of 3.40 m/s, and high correlation coefficient of 0.88, demonstrating an improvement of 20.4% in RMSE (root-mean-square error) compared with the HY-2B/C/D wind speed products. In addition, the revised high winds are in good agreement with the ground truth measurements from the SFMR (Stepped Frequency Microwave Radiometer), which are useful for tropical cyclone disaster prevention and mitigation and are of vital importance in the numerical simulation of storm surges. [ABSTRACT FROM AUTHOR]

Accurate information on tropical cyclone position, intensity, and structure is critical for storm surge prediction. Atmospheric reanalysis datasets can provide gridded, full coverage, long-term and multi-parameter atmospheric fields for the research on the impact of tropical cyclones on the upper ocean, which effectively makes up for the uneven temporal and spatial distribution of satellite remote sensing and in situ data. However, the reanalysis data cannot accurately describe characteristic parameters of tropical cyclones, especially in high wind conditions. In this paper, the performance of the tropical cyclone representation in ERA5 (European Centre for Medium-Range Weather Forecasts Reanalysis 5th Generation) is investigated and analyzed with respect to IBTrACS (International Best Track Archive for Climate Stewardship) during the period 2018–2020. Comparisons demonstrate that ERA5 winds significantly underestimate the maximum wind speed during the tropical cyclones (>30 m/s) compared to those provided by IBTrACS. An effective wind reconstruction method is examined to enhance tropical cyclone intensity representation in reanalysis data in 94 cases of 31 tropical cyclones 2018–2020. The reconstructed wind speeds are in good agreement with the SFMR (Stepped Frequency Microwave Radiometer) measured data and SMAP (Soil Moisture Active Passive) L-band radiometer remotely sensed measurements. The proposed wind reconstruction method can effectively improve the accuracy of the tropical cyclone representation in ERA5, and will benefit from the establishment of remote sensing satellite retrieval model and the forcing fields of the ocean model. [ABSTRACT FROM AUTHOR]

The world's largest living glass sponge reefs, located in the Hecate Strait and Queen Charlotte Sound off British Columbia, are impacted by bottom contact fishing gear. The existing Adaptive Management Zones (AMZs) for the protection of these reefs were determined by considering the potential exposure of glass sponges to suspended sediment due to mobile bottom-contact fishing, but without considering their pumping arrest threshold concentrations. Here, we develop a new method that uses a sediment transport model under horizontally variable near-bottom currents and newly available sponge reef pumping arrest thresholds to determine the size and shape of AMZ for the northern reefs in the Hecate Strait and Queen Charlotte Sound Marine Protected Area. The resulting AMZ is larger than the existing AMZ due to the observation that the largest currents are not always in the direction of the dominant tidal flows, the introduction of the new pumping arrest threshold, and the inclusion of a background sediment concentration. The new AMZ boundary could provide more adequate protection for the glass sponge reefs from the effects of sedimentation induced by mobile, bottom-contact fishing activity. The new method is applicable to other glass sponge reefs in British Columbia waters. [ABSTRACT FROM AUTHOR]

The shelf-edge and continental slope current off the west coast of Canada has been monitored at a site off West Vancouver Island since 1985. However, observations at this site may not represent the characteristics of the shelf-edge and slope current off the entire west coast of Canada. Here, we use along-track satellite altimetry data over six transects to investigate the characteristics of the surface geostrophic currents over the shelf edge and continental slope off the west coast of Canada from 1992 to 2020. It is shown that along-track satellite altimetry is well suited for monitoring longshore and climatic variations of the near-surface shelf-edge and slope currents off the west coast of Canada. It is found that the surface current over the shelf edge and slope has different features from the south to the north. While the surface current is poleward in winter and equatorward in summer off South Vancouver Island, it is poleward year-round off the rest of the west coast of Canada. The seasonal current anomalies show longshore correlation significant at the 95% confidence level, except at the North Haida Gwaii transect. The first empirical orthogonal function mode of the seasonal current anomalies is correlated with the longshore wind anomalies both off South Vancouver Island and off Oregon. However, this first mode is not correlated with either the Niño 3.4 index or the Pacific Decadal Oscillation index, though they often show large episodic events during strong El Niño and La Niña years. Consistent with previous findings, the present study indicates that the surface currents over the shelf edge and continental slope off the west coast of Canada are related to regional and remote longshore wind forcing. [ABSTRACT FROM AUTHOR]

A mathematical model is formulated to simulate dam-break transient debris flows, in which the debris and water mixture is assumed to be isotropic and continuous. In terms of its viscoelastoplasticity, a three-dimensional (3D) rheologic model for Bingham body is used to describe the relationship between the stress tensor and the rate of strain. Only the deformation caused by the deviatoric stress tensor is taken into account. Under the prior considerations, the governing equations for two-dimensional (2D) depth-averaged transient debris flows are obtained by integrating the equation of continuity and equations of motion over depth for 3D flows. To deal with the transient and high-speed features of dam-break debris flows, the derived governing equations are discretized and solved using the method of characteristics. The model is applied to simulate the dam-break debris flow of April 30, 1986, for the Jinshan debris reservoir in Anhui, China. The debris and water mixtures reach as far as 900 m downstream from the initial tailings dam site, with a depth of 1.7 m near the tailings dam and 1.0 m at 900 m downstream. These model results are in good agreement with the available observations.

A comprehensive field survey was conducted, and a numerical model based on the Princeton Ocean Model was established to investigate the vertical structure of current induced by surface waves and identify its effect on sand loss from a beach. Previous studies have examined wave‐induced longshore transport, whereas this study focused on cross‐shore transport caused by waves. The introduction of vertically dependent radiation stress revealed that wave‐induced vertical gyres existed with onshore and offshore flows in the upper and lower layers, respectively, besides the well‐known wave‐induced longshore flow. It was found that the vertical gyres were caused by the onshore wave force (a gradient of radiation stress) in the upper layer and the offshore wave force usually existed in the lower layer, as well as the horizontal imbalance of local wave force. The locations of wave‐induced vertical gyres were found to correspond to the location of sediment erosion, and thus the lower part of the vertical gyres drove the offshore transport of eroded sediment. Moreover, the vertical gyres were located in areas with a highly variable topographic gradient (e.g., at a bar), and their driven offshore currents (undertow/return flow) extended far beyond the surf zone. The topographic slope had a profound effect on the vertical structure. Numerical experiments showed that an extended breakwater from the eastern headland of the bay could prevent sediment from being eroded. Furthermore, the shear front at the rim of a horizontal gyre could retain suspended sediment in the center of the gyre. Plain Language Summary: Rather than examining longshore flow, which has been extensively investigated, this study focused on cross‐shore flow due to waves. It was found that in addition to the longshore flow (vertically mean), a wave‐induced offshore flow component extended a long‐distance offshore. Moreover, the vertical and horizontal gyres (eddies) generated by waves greatly contributed to sand loss from a beach. Specifically, a vertical gyre eroded sediment and drove its offshore transport in the lower layer of water. Furthermore, it was determined that the vertical and horizontal gyres were both affected by highly variable topographic slopes, and that the fast‐rotating rim of a horizontal gyre ensured that suspended sediment was retained in the center of the gyre. The results suggest that a breakwater extending from the eastern headland could prevent the erosion of sediment in the bay, as simulations showed that the pattern of wave‐induced currents was mainly influenced by the length of barriers (headlands) and the bottom slope. Key Points: In addition to vertically mean longshore flow, there was a prevalent wave‐induced offshore component of flowWave‐induced vertical gyres were found to erode sediment and drive its offshore transportNumerical experiments showed that a breakwater at the eastern headland of the bay could prevent the erosion of sediment [ABSTRACT FROM AUTHOR]

The potential mymargin for improving storm surge simulation is demonstrated by using winds derived from ground-based Global Navigation Satellite System Reflectometry (GNSS-R) that uses BeiDou geostationary Earth orbit (GEO) satellite signals. We reconstruct wind fields by blending GNSS-R coastal winds with the European Center for Median Weather Forecasts (ECMWF) reanalysis product. The reconstructed winds agree well with the weather station data collected at Yangjiang in Guangdong, China. The ECMWF winds and the reconstructed winds are used to force a storm surge model off the Chinese coast during typhoon Utor 2013, respectively. The model storm surges forced by the reconstructed winds agree substantially better with tide-gauge observations than those forced by the ECMWF winds. The average error has been reduced by 30.5% from 24.3 cm with the ECMWF winds to 16.9 cm with the reconstructed winds. This letter suggests that GNSS-R coastal winds can have a positive impact on the accuracy of storm surge hindcasting directly and forecasting indirectly by improving the initial conditions. [ABSTRACT FROM AUTHOR]

The effect of climate change on ocean circulation and environmental conditions will likely impact important fisheries species which have a limited habitat range and a prolonged larval dispersal phase. Based on projections from a regional scale ice‐ocean model (RCP 8.5 scenario), we investigated the spatial distribution variability of the bentho‐pelagic northern shrimp (Pandalus borealis) preferred depth and thermal habitat and larval settlement patterns in the Newfoundland and Labrador waters for the next 70 years. Our projections of ocean temperature revealed the persistence of major shelf‐scale temperature features, but a gradual increase of bottom water temperatures by more than 4°C by 2090. Such warming led to an expansion of the potentially suitable habitat for northern shrimp from 2010 to 2050 prior to a decline and shift towards more coastal and southern areas from 2060 to 2090. The modification of the northern shrimp suitable habitat distribution, associated with changes in the ocean circulation features, affected the settlement patterns from larval dispersal simulations and the temperatures encountered by larvae. During the projection period, historically important areas were mostly negatively impacted in terms of suitable habitat and settlement potential, whereas areas that had been less important in the past (e.g., the north and the shallow area to the south) were projected to receive more settlers in comparison with the historical period. Our study demonstrated the important role of shelf‐scale processes in determining larval connectivity and suggests that regional scale ocean models are needed to assess potential impacts of climate change on fisheries and ecosystems. [ABSTRACT FROM AUTHOR]

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While the dynamics of narrow fjords, i.e. narrow with respect to their internal Rossby radius, have been widely studied, it is only recently that interest in studying the physics of broad fjords was sparked due to their importance in glacial ice melting (in Greenland, especially). Here, we present a comprehensive set of data collected in Fortune Bay, a broad, mid-latitude fjord located on the northwest Atlantic shores. Aside from being wide (15–25 km width) and deep (600 m at its deepest), Fortune Bay also has the characteristics of having steep slopes, having weak tides and being strongly stratified from spring to fall. Thus, and since strong along-shore winds also characterize the region, this system is prone to interesting dynamics, generally taking the form of transient upwelling and downwelling travelling along its shores, similar to processes encountered in broad fjords of higher latitudes. The dataset collected to study those dynamics consists of water column physical parameters (temperature, salinity, currents and water level) and atmospheric forcing (wind speed and direction, atmospheric pressure, air temperature, and solar radiation) taken at several points around the fjord using oceanographic moorings and land-based stations. The program lasted 2 full years and achieved a good data return of 90 %, providing a comprehensive dataset not only for Fortune Bay studies but also for the field of broad fjord studies. The data are available publically from the SEANOE repository (10.17882/62314; Donnet and Lazure, 2020). [ABSTRACT FROM AUTHOR]

Previous studies have identified coherent interannual sea level variations along the northwestern Atlantic coasts from New York to Nova Scotia and speculated on possible large‐scale forcing factors such as variations in the Gulf Stream strength and alongshore winds. Here we combine in situ measurements, satellite observations, and oceanic and atmospheric reanalysis data to examine interannual sea level variations during 1993–2012 along the Mid‐Atlantic Bight and the Nova Scotia coast and to provide quantitative analyses of individual factors contributing to the interannual sea level variations. The present study shows not only spatial correlation of the sea level variations but also similarity and difference in their contributing factors in the two areas. The interannual sea level variations along the Nova Scotia coast and the Mid‐Atlantic Bight are mainly (41% and 52%) from the steric effect associated with the temperature and salinity changes, and to a less extent (33% and 31%) from the inverse barometric effect. However, the coastal sea level anomalies are significantly correlated with the Gulf Stream strength along the Mid‐Atlantic Bight only, with correlation coefficient of 0.64, while the correlation with alongshore winds is significant along the Nova Scotia coast only. Plain Language Summary: The northwestern Atlantic coast is vulnerable to the influence of sea level change. Some common factors are often used to explain interannual sea level variations and these individual contributors are considered coherent along the northwestern Atlantic coast extending from north of Cape Hatteras to Nova Scotia shelf, by looking at the domain as a whole. Nevertheless, the domain is located in the subpolar and subtropical intergyre region. There are significant differences in atmospheric and oceanic settings from the north to the south, and thus, it is warranted to further examine these forcing factors by contrasting the north, the Nova Scotia Coast, with the south, the Mid‐Atlantic Bight. The present study shows not only the spatial correlation of the interannual sea level variations but also similarities and differences in their underlying forcing. [ABSTRACT FROM AUTHOR]

The Eastern Canadian northern shrimp population, representing one of the most important fisheries in the region, decreased dramatically since the mid‐2000s to a historical low in 2017, but changes were not spatially uniform. Applying a biophysical model within Newfoundland and Labrador (NL) management areas, we investigated connectivity processes during the long pelagic larval phase (2–3 months) of Pandalus borealis and key drivers of larval dispersal in different environmental conditions. We selected 3 years representative of contrasting North Atlantic Oscillation (NAO) phases to assess potential larval dispersal patterns of the northern shrimp population in NL, and hierarchically assessed the impact of the timing of release (yearly and daily), release location, and vertical migration behaviour on shrimp larval dispersal. Overall, we found that populations located on the northern Newfoundland and Labrador shelf supplied potential settlers to southern populations because of the dominant Labrador Current. Ocean circulation and current velocities during the NAO positive year differed from other years, generating contrasting settlement spatial patterns. Larval release location and vertical migration behaviour were the two most important influences on the strength of larval supply and settlement patterns. Inclusion of diel and ontogenic swimming behaviour increased settlement success of larvae released from inshore areas, regardless of study years. Our study improves understanding of northern shrimp stock‐recruitment relationships, their sensitivity to changing environmental conditions, and spatially non‐homogeneous population decline for bentho‐pelagic species with a long larval phase, which could potentially help improve management strategies. [ABSTRACT FROM AUTHOR]

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Summer upwelling occurs frequently off the southeast Vietnam coast in the western South China Sea (SCS), where summer phytoplankton blooms generally appear during June-August. In this study, we investigate inter-annual variation of Ekman pumping and offshore transport, and its modulation on summer blooms southeast of Vietnam. The results indicate that there are low intensities of summer blooms in El Niño years, under higher sea surface temperatures (SST) and weaker winds. However, a different pattern of monthly chlorophyll a (Chl-a) blooms occurred in summer of 2007, a transitional stage from El Niño to La Niña, with weak (strong) wind and high (low) SST before (after) early July. There is a weak phytoplankton bloom before July 2007 and a strong phytoplankton bloom after July 2007. The abrupt change in the wind intensity may enhance the upwelling associated with Ekman pumping and offshore Ekman transport, bringing more high-nutrient water into the upper layer from the subsurface, and thus leading to an evident Chl-a bloom in the region. [ABSTRACT FROM AUTHOR]

Mean relative sea level (MRSL) rise has caused more frequent flooding in many parts of the world. The MRSL rise varies substantially from place to place. Here we use tide-gauge data and satellite measurements to examine past MRSL trends for the coasts of the China Seas. We then combine climate model output and satellite observations to provide MRSL projections in the 21st century. The MRSL trend based on tide-gauge data shows substantial regional variations, from 1 to 5 mm/yr. The vertical land motion (VLM) based on altimetry and tide-gauge (ATG) data indicates large land subsidence at some tide-gauge locations, consistent with the Global Positioning Systems (GPS)-based VLM but different significantly from small uplift estimated by a Glacial Isostatic Adjustment (GIA) model, which suggests other important factors causing the VLM instead of the GIA process. When GPS- or ATG-based VLM estimates are used, the projected MRSL rise between 1986–2005 and 2081–2100 at tide-gauge sites varies from 60 to 130 cm under the Representative Concentration Pathway 8.5 (RCP8.5) scenario of the Intergovernmental Panel on Climate Change (IPCC). Our projections are significantly larger than those of IPCC and other literature, as a result of accounting for the land subsidence derived from observations. Steric and dynamic ocean effects and land-ice melt effects are comparable (about 30 cm each) and do not vary much over the tide-gauge locations. The VLM effect varies from −10 to 60 cm. The projections between 1986–2005 and 2081–2100 under RCP4.5 show a similar spatial distribution to that under RCP8.5, with a smaller amount of rise by 18 cm on average for this region. [ABSTRACT FROM AUTHOR]

The Northwest Atlantic continental slope features strong interactions among the western boundary currents of the subpolar and subtropical gyres, and, thus, the sea-level variability over the slope may be an indicator for the large-scale ocean circulation. In this study, temporal and spatial sea-level variability in the Northwest Atlantic continental slope has been investigated based on a satellite altimetry dataset and a temperature and salinity dataset. The altimetric results from 1993 to 2012 are compared with steric height anomalies relative to 1500 m, calculated from the temperature and salinity dataset. This study shows significant interannual and decadal sea-level variability, with prominent regional differences and varying linkages to large-scale atmospheric and oceanic variability in the North Atlantic. Both the altimeric and steric height anomalies in the western Labrador Sea are negatively correlated with the winter North Atlantic Oscillation (NAO) index primarily via wintertime deep convection. The altimetric height anomalies in the Laurentian Fan have a weak (insignificant at the 95% confidence level) positive correlation with those in the Labrador Sea, while the steric height anomalies have a negative correlation. The thermosteric (halosteric) height anomalies in the Labrador Sea are negatively (positively) correlated with the winter NAO index, while those in the Laurentian Fan are not correlated with the winter NAO index. The along-slope differences in the interannual and decadal variations of the sea surface height anomalies imply that there is an interior pathway of the southward-flowing Labrador Sea intermediate water toward the central North Atlantic basin before reaching 55 ˆN. [ABSTRACT FROM PUBLISHER]

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The article reports that the Minister of the Environment has announced a $148.8 million Government of Canada climate change adaptation initiative. It states that the projections provided a baseline from which additional teams of scientists and economists could conduct impact and vulnerability assessments at the basin and sub-basin scale. It reports that the flooding is caused by extreme sea level as a combination of high storm surge and wave run-up associated with hurricanes and typhoons.

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Copyright of Atmosphere -- Ocean (Taylor & Francis Ltd) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atmosphere -- Ocean (Taylor & Francis Ltd) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Typhoons can cause strong disturbance, mixing, and upwelling in the upper layer of the oceans. Rich nutrients from the subsurface layer can be brought to the euphotic layer, which will induce the phytoplankton to breed and grow rapidly. In this paper, we investigate the impact of an intense and fast moving tropical storm, Typhoon Matsa, on phytoplankton chlorophyll-a (Chl-a) concentration off East China. By using satellite remote sensing data, we analyze the changes of Chl-a concentration, Sea Surface Temperature (SST) and wind speed in the pre- and post-typhoon periods. We also give a preliminary discussion on the different responses of the Chl-a concentration between nearshore and offshore waters. In nearshore/coastal regions where nutrients are generally rich, the Chl-a maximum occurs usually at the surface or at the layer close to the surface. And, in offshore tropical oligotrophic oceans, the subsurface maxima of Chl-a exist usually in the stratified water column. In an offshore area east of Taiwan, the Chl-a concentration rose gradually in about two weeks after the typhoon. However, in a coastal area north of Taiwan high Chl-a concentration decreased sharply before landfall, rebounded quickly to some degree after landfall, and restored gradually to the pre-typhoon level in about two weeks. The Chl-a concentration presented a negative correlation with the wind speed in the nearshore area during the typhoon, which is opposite to the response in the offshore waters. The phenomena may be attributable to onshore advection of low Chl-a water, coastal downwelling and intensified mixing, which together bring pre-typhoon surface Chl-a downward in the coastal area. In the offshore area, the typhoon may trigger increase of Chl-a concentration through uptake of nutrients by typhoon-induced upwelling and entrainment mixing. [ABSTRACT FROM AUTHOR]

Copyright of Atmosphere -- Ocean (Taylor & Francis Ltd) is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)