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Satellite observations of the Antarctic surface since the 1990s, coupled with geophysical surveys of the flow and form of its giant ice sheet, have revealed accelerating loss of ice to the oceans. This, coupled with a reduction in floating sea ice surrounding the continent and the occurrence of unprecedented heatwaves, point to a continent being changed irreversibly by fossil-fuel burning and the global heating that results. A changing Antarctic continent will have global consequences, including sea level rise of possibly more than 1 meter in this century (and much more afterward) and by a reduced ability to naturally reflect incoming solar energy—which would lead to further heating by absorption on land and at sea as the ice pack retreats. [ABSTRACT FROM AUTHOR]

Glaciers are the ambassadors of climate change. Their worldwide decline has serious impacts on natural hazards, the water cycle, and sea level rise. The monitoring of glaciers documents the increasingly rapid melting, which has culminated in a suite of extreme years—for example, 2023 in North America and the European Alps. Numerical simulations of future glacier change, supported by a large basis of observational data, allow us to understand the enormous changes ahead and prepare us for a world without glaciers. Technical approaches to reduce glacier melting have been developed and are applicable locally—for example, in connection with tourist activities—but they clearly fail at the larger scale. [ABSTRACT FROM AUTHOR]

Municipal bond markets began pricing sea-level rise (SLR) exposure risk in 2013, coinciding with upward revisions to worst-case SLR projections and accompanying uncertainty around these projections. The effect is larger for long-maturity bonds and not solely driven by near-term flood risk. We use a structural model of credit risk to quantify the implied economic impact and distinguish between the effects of underlying asset values and of uncertainty. The SLR exposure premium exhibits a trend different from house prices and is unaffected by house price controls. Together, our results highlight the importance of climate uncertainty in driving municipal bond prices. Authors have furnished an Internet Appendix , which is available on the Oxford University Press Web site next to the link to the final published paper online [ABSTRACT FROM AUTHOR]

The Holocene infill of an intermittently open-closed barrier estuary (Painkalac Creek/Aireys Inlet) was examined on the southern margins of Australia, through aerial LiDAR, coring, sedimentology, radiocarbon dating and pollen analysis. It is found that almost all the accommodation space within the estuary has been occupied, with a thick sequence (>9 m) of sediments being deposited rapidly soon after flooding by the sea. The rate of sedimentation was 4.8 mm/year which closely matches the rate of sea level rise (4.5 mm/year) during the 1200 year period that the estuary infilled, from around 8000–6800 years ago. The evidence of estuarine deposition above the elevation of the modern intertidal zone provides significant further evidence for the presence of the mid-Holocene highstand sea level in this relatively unstudied part of the Australian coast. The pattern of infill departs from the traditional barrier evolution models. The first phase of infill was likely tide dominated with subtidal sand shoals being found landward of a subtidal bedrock sill. Once a beach-barrier sequence formed, the estuary infilled in a more traditional manner, with lateral progradation of a flood tide delta and central mud basin infill. The barrier estuary of Painkalac Creek therefore has undergone a complex evolutionary history, characterised by a change in process dominance from classic tidal to wave-dominated form. Infill occurred in a keep-up (or fast catch-up) mode, with geological control occurring in regard to the presence of an intertidal bedrock sill at the mouth of the estuary. [ABSTRACT FROM AUTHOR]

AMS radiocarbon-dated palynological evidence from Embilikala Lagoon in Bundala National Park (one of the Ramsar wetland sites) on the southeast coast of Sri Lanka indicates palaeoenvironmental changes during the last 2,700 years. The persistence of fewer mangroves (eg Rhizophoraceae taxa) suggests that sea level low stands occurred between 2,700 and 1750 cal yr BP. From the later age, the relative sea level rose, and reached the present sea level at 950 cal yr BP as indicated by the mangrove maximum. At 2,250, 700–400 and 200–150 cal yr BP, the sudden increase in marine dinoflagellate cysts (eg Spiniferites mirabilis) and foraminifera (Globigerinoides ruber) suggests increased marine influence. This is consistent with a decrease in mangrove habitats. Between 2,700 and 950 cal yr BP, severely degraded dry monsoon forests and minimal levels mangrove suggest human and marine influences were the critical drivers for changing the major vegetation types along the southeastern coast. Vegetation changes have been drastic over the last millennia. [ABSTRACT FROM AUTHOR]

Purpose: Tibetan patients undergoing total knee arthroplasty (TKA) have greater fluctuations in perioperative haemoglobin levels and blood hypercoagulability. This study was to investigate whether ethnicity and altitude affect perioperative blood loss and the risk of complications after TKA. Methods: We retrospectively enrolled 1,116 patients undergoing TKA for knee osteoarthritis at our hospital between January 2016 and September 2021. We divided patients into four groups according to whether they were of Tibetan or Han ethnicity and whether they lived above or below 2500 m above sea level. Primary outcomes were total, intraoperative, and hidden blood losses, while secondary outcomes were complications and homologous transfusion. Factors associated with increased blood loss were analyzed by multivariate regression. Results: Total blood loss was higher among patients residing at high altitude compared with lower altitude, whether they were of Han (794.6 mL vs. 667.2 mL, P = 0.020) or Tibetan (904.4 mL vs. 663.8 mL, P < 0.001). Total blood loss was similar between the two ethnic groups at the same altitude. Altitude, but not Tibetan ethnicity, remained associated with increased blood loss after being analyzed by multivariate regression. Complications among the four groups were generally similar, although the frequency of calf muscular venous thrombosis was higher among Tibetan patients, while the frequency of blood transfusion was higher among Han subjects. Conclusions: Our findings indicate that residence at high altitude, but not ethnicity, may contribute to increased total blood loss during TKA. Thrombotic complications were more frequent among Tibetan than Han patients. [ABSTRACT FROM AUTHOR]

Antarctica has been proposed as a significant source of the meltwater that entered the oceans during meltwater pulse 1B (MWP1B) approximately 11 500 yr ago. Support for this scenario has been provided by evidence that the deep fjords of coastal Antarctica, which were heavily glaciated at the maximum of glaciation, were deglaciated at this time. Further support for this scenario was provided by the observation that the inter-hemispheric sea-level teleconnection associated with significant Southern Hemisphere deglaciation at this time provided an explanation of the highly non-monotonic relative sea-level histories recorded at sites on the coast of Scotland, a region which had also been heavily glaciated at the last glacial maximum. Furthermore, it has been argued that a significant contribution to MWP1B must have also been delivered to the oceans by the abrupt Northern Hemisphere warming that occurred at the end of the Younger Dryas (YD) cold reversal, which also occurred approximately 11 500 yr ago. Our focus in this paper is to distinguish between these two possible primary sources of MWP1B. The investigation of how local alterations to ice thicknesses are able to explain evidence which has previously been used to argue for an Antarctic dominant MWP1B will lead us to the conclusion that the Laurentide may be primary source of MWP1B. [ABSTRACT FROM AUTHOR]

Mineral dust from the Sahara desert can travel long distances at high altitudes, perturbing the energy budget of the atmosphere. Charging of dust has been observed to occur near the surface through triboelectric charging during dust lofting, potentially affecting particle coagulation, fall speeds, and the lofting process itself. Apart from near-surface studies, measurements at elevated dust layers, where charge may play a role in particle long-range transport, are rare. This study presents new observations from an uncrewed aircraft system (UAS) of type MASC-3, through an elevated Saharan dust layer over Cyprus on 6 April 2022. The dust layer ranged from 1500 to 2500 meters above sea level (a.s.l), with maximum particle number concentrations (PNC) of 80–100 cm − 3 , primarily consisting of particles up to 2.5 µm in size. Measurements showed elevated charge within the dust layer, with magnitude proportional to PNC. It was concluded that there was a small influence of aircraft charge on the measurements, which was handled by developing a PNC-based correction factor. Corrected charge within the dust layer ranged from 0.2 to 3 pC m − 3 , with most of the charge at the upper and lower dust layer boundaries. The magnitude and location of the charge was consistent with predictions of ion-particle attachment. This suggests that most of the measured charge did not originate from the lofting process, but dust particles were charged on site through ion-particle attachment processes. [ABSTRACT FROM AUTHOR]

The article discusses the modernization of the National Spatial Reference System (NSRS) by the National Geodetic Survey (NGS) in the United States. The modernization involves updating reference frames and vertical datums, impacting the geospatial industry. The benefits of the Modernized NSRS include improved accuracies and enhanced interoperability. The article provides recommendations for industry professionals to prepare for the upcoming changes and emphasizes proactive measures for a smooth transition to the new reference frames and vertical datum. [Extracted from the article]

Coastal salt marshes of the eastern United States are particularly vulnerable to accelerated sea level rise, and urban marshes are at greater risk of erosion, inundation, and conversion to mudflat if left unmanaged. To guide New York City (NYC) salt marsh restoration strategies, NYC Parks collected up to 10 years of salt marsh elevation change data through 2020 at six salt marsh sites using the Surface Elevation Table-Marker Horizon (SET-MH) method, conducted a salt marsh trends analysis to determine shoreline change from 1974 to 2012, and conducted a salt marsh conditions assessment. We found that the citywide average surface elevation trend of 3.31 mm yr−1 was not significantly different from the 30-year (1990–2020) Relative Sea Level Rise of 4.23 mm yr−1 at The Battery, NY, tide station, probably due to high variability across and within sites. We also found that accretion rates differed across sites and watersheds, and sites situated lower in the tidal zone had higher accretion rates. Notably, Jamaica Bay's Idlewild salt marsh, long suspected of being sediment-starved and ranking lowest in our conditions assessment, had the highest accretion rate at 9.5 mm yr−1. Our salt marsh trends analysis also showed marsh loss at the shoreline edge, bare ground cover, and other indicators of marsh degradation. In mitigating marsh loss, the design grades for our recent wetland restoration projects enlarge the upper elevation ranges of the low- and high-marsh zones and incorporate wider and more gradual slopes in upland transition zones to enable inland marsh migration. [ABSTRACT FROM AUTHOR]

We compared elevation trajectories from 14 rod surface elevation table (RSET) stations and 60 real-time kinematic (RTK) global positioning system (GPS) transects within the Blackwater National Wildlife Refuge (BNWR) from 2010–2013. The results were similar, 7.3 ± 0.9 (mean ± standard error; RSET) versus 6.2 ± 0.6 mm year−1 (RTK) (P = 0.216), and were greater than relative sea level rise (RSLR) computed at the nearest long-term tide station (3.9 ± 0.29 mm year−1). Despite having shown elevation gain, these wetlands continue to drown and convert to open water. Episodic, multi-day GPS measurements on geodetic control marks at BNWR between 2005 and 2023 revealed a substantial vertical land motion (VLM) signal. From 2005 to 2015, three reference marks used to control the 2010–2013 RTK study lost on average 6.0 ± 0.7 mm year−1, corresponding to 80% and 94% of the elevation gain measured by the RSET and RTK techniques, respectively. The longer 18-year subsidence trend measured on one of these marks was lower, 3.9 ± 0.7 mm year−1, highlighting important interannual variability. Wetland elevation change measurements need to account for VLM occurring below the reference marks used to measure elevation change. Estimates from the nearest long-term tide station may not be applicable to the wetland if the tide station is in a different geological setting. At BNWR, VLM was higher than the VLM at the Cambridge tide station, which helps explain why wetlands at BNWR are not keeping pace with RSLR despite the measured high rates of elevation gain. [ABSTRACT FROM AUTHOR]

The Ganges-Brahmaputra Delta (GBD) in Bangladesh exists at a nexus of stability and vulnerability, as the rivers annually carry ~ 800–1000 MT of sediment from the Himalayan Mountains, yet coastal poldering and sediment extraction within the rivers remove elevation capital from the low-lying delta plain. Recent research in the GBD has begun to unravel how the world's largest fluvio-deltaic mangrove forest—the Sundarbans—is keeping pace with sea level rise (SLR); however, this is contingent on adequate sediment supply delivered to the platform during semi-diurnal tides and the seasonal monsoon. Little is known about the elevation dynamics within human-modified polders by comparison, other than an elevation deficit of 1–1.5 m exists. In this study, seasonal data from Rod Surface Elevation Tables (RSETs) installed within a polder in the southwest region (Polder 32) are compared to the Sundarbans. Over ~ 8 years, results show that surface elevation is gaining within the Sundarbans at a more significant rate (~ 58.4%), and this is due to the higher vertical accretion rates measured in the Sundarbans (~ 67%) from abundant sources of allochthonous material. Elevation gain in the polder, particularly close to the embankment, appears to be attributed to sediment supplied from eroded embankments and local sluice gates, in addition to seasonal subsurface clay swelling during the monsoon. Shallow subsidence within both study areas appears to take place seasonally, but with less delivery of new sediment, the rate of shallow subsidence is lower in the polder compared to the Sundarbans. Despite seasonal shallow subsidence, the elevation change is net positive in both study areas if taken as a whole; however, interior poldered regions exhibit net elevation loss. This comparison in change of elevation, vertical accretion, and shallow subsidence shows how human modification has drastically changed the natural processes. Furthermore, our results are compared to rates of relative and effective SLR, which show that the Sundarbans is keeping pace in this region, while Polder 32 is not. These results are vital to inform embankment mitigation and flood risk in this dynamic delta system. [ABSTRACT FROM AUTHOR]

Tidal marshes in the Chesapeake Bay are vulnerable to the accelerating rate of sea-level rise (SLR) and subsidence. Restored and created marshes face the same risks as natural marshes, and their resilience to SLR may depend upon appropriate design and implementation. Here, the Coastal Wetland Equilibrium Model (CWEM) was used to assess the resilience of tidal marshes at the Paul S. Sarbanes Ecosystem Restoration Project at Poplar Island (PI) in mid-Chesapeake Bay, MD, where dredged material from navigation channels is being used to create new tidal marshes planted with Spartina alterniflora in the low marsh and S. patens in the high marsh. The site is microtidal with low inorganic sediment inputs, where the rate of marsh elevation change is dominated by the production of organic matter and, therefore, is proportional to net ecosystem production (NEP). The model demonstrated the importance of marsh development for surface elevation gain. In created marshes, the buildout of belowground biomass adds volume and results in faster growth of marsh elevation, but the gains slow as the marsh matures. Elevation gain is the lessor of the recalcitrant fraction of NEP sequestered in sediment or the rate of increase in accommodation space. Marshes can keep up with and fill accommodation space with sequestered NEP up to a tipping point determined by the rate of SLR. The PI low marsh platform was forecasted to drown in about 43 years after construction at the current rate of SLR. Marsh loss can be mitigated by periodic thin layer placement (TLP) of sediment. CWEM was used to simulate PI marsh responses to different TLP strategies and showed that there is an optimal design that will maximize carbon sequestration and resilience depending on the trajectory of mean sea level. [ABSTRACT FROM AUTHOR]

Estuarine systems that provide valuable ecosystem services to society and important foraging and rearing habitat for fish and wildlife species continue to undergo degradation. In Puget Sound, WA, as much as 70–80% of historic estuarine habitat has been lost to anthropogenic development, and continued losses are expected through the end of the twenty-first century due to rising sea levels. To evaluate whether Puget Sound's estuarine habitats will keep pace with current and projected sea-level rise (SLR), we assessed vertical rates of elevation change from a regional network of surface elevation tables and marker horizons (SET-MH). Over the past two decades, SET-MH equipment has been installed throughout a variety of habitats in five Puget Sound estuaries: the Nisqually, Snohomish, Stillaguamish, and Skagit River estuaries, and Padilla Bay. These data provide a unique opportunity to assess elevation change and habitat resilience across a spatiotemporal and environmental gradient. We observed different rates of surface elevation change among estuaries and habitats (Nisqually = 4.64 ± 2.81 mm/year, Snohomish = 5.71 ± 5.83 mm/year, Stillaguamish = 12.82 ± 10.29 mm/year, Skagit = 16.13 ± 7.57 mm/year, Padilla = − 1.25 ± 1.58 mm/year). The highest rates were found at restoring sites with regular sediment input in the Stillaguamish and Skagit estuaries, whereas rates were consistently negative at low elevation sites in sediment starved Padilla Bay. Many sites in Puget Sound appear to be keeping pace with current rates of relative SLR, and some areas are on track to exceed projected rates through the end of the century. These findings indicate that Puget Sound's estuarine habitats can be resilient to rising tidal levels—as long as sediment delivery is maintained. [ABSTRACT FROM AUTHOR]

Tidal freshwater marshes (TFMs), found in the upper tidal reaches of river estuaries, are characterized by high diversity and productivity. These ecosystems are threatened by climate change, but unlike other coastal wetlands, there is a lack of information about the impact and their response to this threat. To understand the resilience of Jug Bay TFMs to sea level rise (SLR), surface elevation change was measured in low and mid-high marsh areas along primary and secondary channels. Elevation change exhibited significant temporal and spatial variability. A marked seasonality showed higher elevation during the growing season, and episodic storms altered elevation trajectories. Spatially, elevation change was significantly affected by channel category and marsh zone. Low marsh along primary channels lost elevation (−11.57 mm year−1), while the mid-high marsh gained elevation (+2.65 mm year−1). In secondary channels, both low (+11.29 mm year−1) and mid-high marshes (+5.43 mm year−1) gained elevation. A shoreline change analysis for the Patuxent and Western Branch rivers (2007–2018) showed change rates between −0.35 and −0.90 m year−1. A 2019 upland migration study indicated that most TFMs studied are not able to migrate due to steep slopes. Overall, marsh in more protected areas, along secondary channels, are more resilient, while low marsh in primary channels the most vulnerable to SLR. With low upland migration potential, studied marshes have to rely mainly on vertical elevation gain to keep up with SLR. If restoration is considered in this system, it should focus on the vulnerable low marsh zones along primary channels. [ABSTRACT FROM AUTHOR]

Tidal marshes build elevations by below- and aboveground organic and mineral soil processes. Marsh elevation and accretion data can be used to determine if marshes are keeping pace with sea-level rise. Using a network of 54 deep rod surface elevation tables with paired feldspar marker horizon plots, we tracked elevation and accretion trends across 16 marshes in California, USA. All sites had overall positive gains across years that included severe drought conditions and extreme rain events. Marsh elevation relative to tidal datum (z*) was the key predictor for elevation and accretion rates, with higher change rates at lower z* sites. Marsh sites are clustered into three regional groups (Northern California, San Francisco Bay area, and Southern California), primarily defined by maximum temperature and annual rainfall differences. Elevation, accretion, and shallow subsidence rates were not significantly different between clusters, but their explanatory variables did vary. High-temperature days were a key predictor for elevation, accretion, and shallow subsidence rates in the state-wide analysis and San Francisco Bay regional analysis. The largest elevation gains were observed in the San Francisco Bay-Delta and some of the smallest in Humboldt Bay, with Morro Bay having the lowest accretion rate overall. Central and Southern California marshes were keeping pace or out-pacing sea-level rise, while none of the Humboldt Bay marshes were keeping pace. Marsh surface elevation data can inform management intervention and be a leading indicator for sea-level rise vulnerability. Long-term monitoring across geomorphic settings can help inform management and anticipate marsh change. [ABSTRACT FROM AUTHOR]

A network of 15 Surface Elevation Tables (SETs) at North Inlet estuary, South Carolina, has been monitored on annual or monthly time scales beginning from 1990 to 1996 and continuing through 2022. Of 73 time series in control plots, 12 had elevation gains equal to or exceeding the local rate of sea-level rise (SLR, 0.34 cm/year). Rising marsh elevation in North Inlet is dominated by organic production and, we hypothesize, is proportional to net ecosystem production. The rate of elevation gain was 0.47 cm/year in plots experimentally fertilized for 10 years with N&P compared to nearby control plots that have gained 0.1 cm/year in 26 years. The excess gains and losses of elevation in fertilized plots were accounted for by changes in belowground biomass and turnover. This is supported by bioassay experiments in marsh organs where at age 2 the belowground biomass of fertilized S. alterniflora plants was increasing by 1,994 g m−2 year−1, which added a growth premium of 2.4 cm/year to elevation gain. This was contrasted with the net belowground growth of 746 g m−2 year−1 in controls, which can add 0.89 cm/year to elevation. Root biomass density was greater in the fertilized bioassay treatments than in controls, plateauing at about 1,374 g m−2 and 472 g m−2, respectively. Growth of belowground biomass was dominated by rhizomes, which grew to 3,648 g m−2 in the fertilized treatments after 3 years and 1,439 g m−2 in the control treatments after 5 years. Depositional wetlands are limited by an exogenous supply of mineral sediment, whereas marshes like North Inlet could be classified as autonomous because they depend on in situ organic production to maintain elevation. Autonomous wetlands are more vulnerable to SLR because their elevation gains are constrained ultimately by photosynthetic efficiency. [ABSTRACT FROM AUTHOR]

In the face of accelerating climate change and rising sea levels, quantifying surface elevation change dynamics in coastal wetlands can help to develop a more complete understanding of the implications of sea-level rise on coastal wetland stability. The surface elevation table-marker horizon (SET-MH) approach has been widely used to quantify and characterize surface elevation change dynamics in coastal marshes and mangrove forests. Whereas past studies that utilized the SET-MH approach have most often quantified rates of surface elevation change using simple linear regression analyses, several recent studies have shown that elevation patterns can include a diverse combination of linear and non-linear patterns. Generalized additive models (GAMs) are an extension of generalized linear models (GLMs) that have previously been used to analyze a variety of complex ecological processes such as cyclical changes in water quality, species distributions, long-term patterns in wetland area change, and palaeoecological time series. Here, we use long-term SET data to demonstrate the value of generalized additive models for analyzing non-linear patterns of surface elevation change in coastal wetlands. Additionally, we illustrate how the GAM approach can be used to effectively quantify rates of elevation change at both landscape- and local site-level scales. [ABSTRACT FROM AUTHOR]

Salt marsh habitat loss and conversion are well documented across the marine-coastal district of New York. Regionally, these losses are characterized by marsh edge erosion, ditch and creek widening, internal ponding, and conversion from irregularly flooded marsh to regularly flooded marsh and intertidal mudflats. These changes in horizontal extent and shifts in vegetation composition suggest that NY's salt marshes may not be keeping pace with sea level rise. To evaluate elevation building processes, deep rod surface elevation tables, marker horizons, and shallow rod surface elevation tables (SET-MHs and shallow RSETs) were installed as a network across Long Island, NY. Contributions of surface, shallow subsurface, and deeper processes to overall elevation changes were observed from 2008 to 2022. Using a linear mixed model approach, surface accretion, shallow subsurface rootzone growth, and deeper below-ground processes were evaluated against regional sea level rise, nutrient loading, and marsh area trends. We found that marshes on Long Island are not keeping pace with sea level rise because they lack vertical elevation growth within the rootzone. Optimizing conditions for belowground growth of native salt marsh plants and preservation of organic matter within the peat matrix is key for restoring salt marshes to a positive elevation trajectory relative to sea level rise. Much like a retirement savings account, knowing whether our marshes are increasing in elevation is important, but understanding the full suite of deposits and withdrawals is critical for managing this valuable resource for the future. [ABSTRACT FROM AUTHOR]

Australian tidal wetlands differ in important respects to better studied northern hemisphere systems, an artefact stable to falling sea levels over millennia. A network of Surface Elevation Table-Marker Horizon (SET-MH) monitoring stations has been established across the continent to assess accretionary and elevation responses to sea-level rise. This network currently consists of 289 SET-MH installations across all mainland Australian coastal states and territories. SET-MH installations are mostly in mangrove forests but also cover a range of tidal marsh and supratidal forest ecosystems. Mangroves were found to have higher rates of accretion and elevation gain than all the other categories of tidal wetland, a result attributable to their lower position within the tidal frame (promoting higher rates of accretion) higher biomass (with potentially higher rates of root growth), and lower rates of organic decomposition. While Australian tidal marshes in general show an increase in elevation over time, in 80% of locations, this was lower than the rate of sea-level rise. High rates of accretion did not translate into high rates of elevation gain, because the rate of subsidence in the shallow substrate increased with higher accretion rates (r2 = 0.87). The Australian SET-MH network, already in many locations spanning two decades of measurement, provides an important benchmark against which to assess wetland responses to accelerating sea-level rise in the decades ahead. [ABSTRACT FROM AUTHOR]

Tidal freshwater forested wetlands (TFFWs) are in an active phase of transition to tidal marsh with sea level rise and salinity incursion along the Atlantic and Gulf Coasts of the United States (U.S.). A prominent feature of TFFWs is hummock/hollow microtopography where hollows represent the flat, base-elevation of the floodplain where inundation occurs relatively frequently, while hummocks provide elevated soil surfaces that often harbor relatively greater numbers and species of trees and shrubs. Hummocks appear at the landscape river boundary just seaward of bottomland hardwoods as tides reach those positions, persist for many years, and disappear as TFFWs eventually transition to marsh. We studied TFFW surface elevation processes along four Atlantic coastal landscape river gradients by using surface elevation tables and marker horizons. Shallow subsidence between trees, equating to as much as 5.5 mm/year, was an important process in hollow maintenance as roots held hummock elevations relatively more stable. However, hummocks were actively subsiding on all sites with little sign of root zone expansion within hummocks, despite hummock elevation gain on some sites. For down-river transitions, hollow infilling through increasing sediment accretion and root zone expansion were predominant processes driving loss of microtopography as marshes replaced TFFWs closer to the estuarine interface; hollows gained elevations to meet hummocks. While these results do not preclude the importance of healthy root zone processes to the maintenance (and formation) of hummocks, our results indicate that reductions in critical sediment supplies to offset natural shallow subsidence explain persistence and eventual loss of hummock and hollow microtopography in TFFWs. [ABSTRACT FROM AUTHOR]

Coastal wetlands experience acute and chronic disturbances which can affect rates of surface elevation change and vertical accretion of surface sediments. Disturbance can either amplify or impair the ability of wetlands to maintain their position within the tidal frame, with implications for their long-term persistence. Using an 8-year dataset collected from coupled surface elevation table-marker horizon (SET-MH) stations spanning riverine, bayside, and barrier island settings in the Apalachicola Bay region of north Florida, USA, this study investigated decadal-scale surface elevation change and vertical accretion rates to assess wetland vulnerability to acute (Hurricane Michael) and chronic (relative sea-level rise; RSLR) disturbance in different geomorphic settings. All sites had long-term accretion rates that exceeded rates of surface elevation change (pre-Michael), indicating that surface accretion was not a good indicator of changes in surface elevation for any of these coastal geomorphic settings. Hurricane Michael increased surface elevation change rates at bayside and riverine sites; barrier island sites consistently displayed the lowest surface elevation change rates, which did not differ between pre- and post-Michael periods. Accretion rates were greatest in the riverine sites, which were characterized by highly organic soils. Barrier island and bayside sites demonstrated elevation and accretion deficits relative to the rate of RSLR for Apalachicola Bay between 2010 and 2022, indicating high vulnerability of these sites to chronic increases in sea level. These estimates of marsh resilience relied exclusively on rates of vertical change and neglecting to account for lateral erosion failed to predict that each of the three barrier island sites experienced rapid loss of the seaward SET-MH stations during the observation period. These results provide evidence of different vertical change responses among coastal wetlands of three geomorphic settings exposed to hurricanes and RSLR in the same region and suggest different timelines for long-term persistence of these sites. [ABSTRACT FROM AUTHOR]

Wave runup, the excess water level above mean sea level, has been measured using different techniques with varying degrees of precision and associated practical limitations. This critical parameter, typically included in coastal assessment studies, varies temporally and spatially and depends on variables that include beach characteristics and nearshore hydrodynamics. Access to continuous datasets, using efficient mechanisms can assist resource-limited regions, such as Caribbean small-island developing states (SIDS), in overcoming coastal resilience obstacles. Experiments were conducted at University College London (UCL) and the University of the West Indies (UWI), which were designed to explore the temporal behaviour of the water surface within the bed during runup events. The experiments encompassed linear waves impacting a static porous bed (UCL) and a moveable granular beach (UWI), with pressure sensors buried at the base of each beach. The analyses showed that the averaged values of the time-varying water elevations within the bed, when spatially presented, produced a quadratic or cubic polynomial fit, where the curves' stationary points were accurate indicators of the location of the maximum runup position at the surface of the bed. In this way, an arrangement of buried pressure sensors can be used as an efficient means to accurately produce a continuous time series of maximum runup positions. This article is part of the theme issue 'Celebrating the 15th anniversary of the Royal Society Newton International Fellowship'. [ABSTRACT FROM AUTHOR]

The possible inundation of an island State by climate change-related sea level rise poses a completely new challenge for international law. The International Law Association Sea Level Rise Committee and the International Law Commission Study Group have concluded that the principles of certainty and stability support the continuity of statehood. This 2023 Declaration by the Pacific Islands Forum, affirms the ‘presumption of continuity’ of statehood in the face of climate change-related sea level rise. It represents a valuable milestone in the development of State practice on the continuity of statehood and the commitment of affected States to protect their populations. [ABSTRACT FROM AUTHOR]

Mangrove forests are critical coastal ecosystems that provide great socio‐ecological services, which are also highly vulnerable to climate change, particularly to sea level rise (SLR). Here we assess changes in mangrove forests in four distinct river/tide/wave‐dominant large deltas along the Indo‐Pacific coast based on 1,336 remote sensing images by machine learning techniques. We find that mangroves are migrating seaward at a rate of 18% ± 12% m/yr, which can offset landward mangroves loss, 67% of which caused by land use conversion. The fact that mangroves are expanding seaward with accretion rates exceeding SLR suggests that climate change has not yet triggered substantial loss in deltaic mangrove forests. Assuming that present environmental conditions do not change and that sediment and organic deposition in the deltaic topsets match SLR rates, we project that 90% of deltaic mangrove forests may start to retreat after 132–194 years. Early inundation of mangroves will occur in wave‐dominated delta. Plain Language Summary: Mangrove forests provide significant ecological and societal services, and mitigation global warming. However, large‐scale loss in mangroves could be induced by anthropogenic drivers and sea level rise (SLR). Our study based on deltas along the Indo‐Pacific coast, highlight that mangroves are expanding seaward at a rate of 18% ± 12% m/yr, indicating that there is little impacts from SLR and has not been substantial loss in mangrove forests in these deltas so far. Mangrove expansion here can efficiently offset 67% landward mangrove losses indicates that our new model project that 90% of mangrove shorelines will may start retreating within 132–194 years. We conclude that favoring mangroves expansion seaward would enhance coastal protection and reduce the need of landward mangrove restoration. Key Points: Mangroves along typical deltas are expanding seaward of about 18% ± 12% m/yr, indicating that there is little impacts from sea level riseMangrove expansion here can efficiently offset 67% landward mangrove lossesNew model project that 90% of mangrove fringes may start retreating within 132–194 years, and wave‐dominated delta present early inundation [ABSTRACT FROM AUTHOR]

Pine Island, Thwaites, Smith, and Kohler glaciers in the Amundsen Sea Embayment (ASE) sector of West Antarctica experience rapid mass loss and grounding line retreat due to enhanced ocean thermal forcing from Circumpolar Deep Water (CDW) reaching the grounding lines. We use simulated Lagrangian particles advected with a looping 1 year output from the Southern Ocean high‐resolution model to backtrack the transport and cooling of CDW to these glaciers. For the simulated year 2005–2006, we find that the median time needed to reach the grounding lines from the edge of the ASE is 3 years. In addition, the Antarctic Coastal Current contributes an equal number of particles as off‐shelf sources to the grounding lines of Pine Island and Thwaites. For CDW coming from off‐shelf, results from SOhi indicate that 25%–66% of the cooling occurs within ice shelf cavities. Plain Language Summary: The glaciers in the Amundsen Sea Embayment (ASE) sector of West Antarctica are contributing rapidly to sea level rise in response to enhanced melt by warm, salty Circumpolar Deep Water (CDW). We use an ocean numerical model to trace the sources, pathways, and cooling of warm waters to reach glacier grounding lines. We find that it takes multiple years for off‐shelf perturbations to reach the glaciers and that the colder Antarctic Coastal Current contributes the same amount of water to the grounding lines of Thwaites and Pine Island glaciers as off‐shelf CDW sources. The model also reveals that half of the cooling of CDW occurs under the ice shelves, which is an effect not accounted for in most models used for projecting sea level rise. Key Points: From a 2005–2006 simulation, it takes about 3 years for water to reach the grounding lines from the edge of the Amundsen Sea EmbaymentThe simulation shows the Antarctic Coastal Current contributing equal amounts of water to Pine Island and Thwaites as off‐shelf sourcesSOhi results indicate that 1/4 to 2/3 of the cooling between the shelf break and the grounding lines occurs within the cavities [ABSTRACT FROM AUTHOR]

Regional patterns of sea level rise are affected by a range of factors including glacial melting, which has occurred in recent decades and is projected to increase in the future, perhaps dramatically. Previous modeling studies have typically included fluxes from melting glacial ice only as a surface forcing of the ocean or as an offline addition to the sea surface height fields produced by climate models. However, observational estimates suggest that the majority of the meltwater from the Antarctic Ice Sheet actually enters the ocean at depth through ice shelf basal melt. Here we use simulations with an ocean general circulation model in an idealized configuration. The results show that the simulated global sea level change pattern is sensitive to the depth at which Antarctic meltwater enters the ocean. Further analysis suggests that the response is dictated primarily by the steric response to the depth of the meltwater flux. Plain Language Summary: The time‐varying pattern of sea level rise is projected to cause some coastal communities to be impacted more than others during the coming century. This pattern is influenced by the melting of Antarctic ice. Previous modeling studies have typically injected this meltwater at the ocean surface, despite observational evidence suggesting that it enters the ocean primarily at depth. Here we use simulations with a model in an idealized configuration to investigate how the sea level change pattern depends on the depth at which Antarctic meltwater enters the ocean. We find that the sea level change signal tends to travel more slowly across the global ocean when the meltwater enters the ocean at depth. These results have implications for projected regional sea level changes in response to the melting of Antarctic ice. Key Points: The depth at which Antarctic meltwater enters the ocean influences global sea level change patterns simulated with an idealized modelThe sea level change patterns tend to travel more slowly across the global ocean when meltwater fluxes occur at depthThe propagation speed of the pattern is dictated primarily by the steric response to the depth of the meltwater fluxes [ABSTRACT FROM AUTHOR]

Tropical carbonate systems are valuable archives of paleoenvironments, as the carbonate growth is intimately affected by water depth and climatic conditions. Geochemical data from the Burdigalian interval in IODP Site U1468 in the Maldives, northern Indian Ocean, were integrated with sedimentological and paleontological data for a more detailed reconstruction of depositional history. Generally, the Sr/Ca values of slope sediments record highstand progradation in both sequence unit and whole Burdigalian interval, while the absence of higher Sr/Ca ratio close to the sequence boundary during the early Burdigalian could be related to the erosion of deeper-water sediments due to the activity of bottom current. From 20.5 to 19.1 Ma and from 17.9 to 17.2 Ma, nutrient level and productivity were moderately elevated due to the terrigenous input by the intensified South Asian Proto-Monsoon, which also helped cause more reducing conditions in the distal slope. Moreover, increased nutrient level facilitated the growths of calcareous algae and sponges, while it was not favorable for coral development. The elevated nutrient level, higher sea level, and monsoon-induced current contributed to the backstepping of the outer margin during the late Burdigalian. Our study shows an example on how a tropical carbonate platform evolved in response to the interplay of sea-level and paleoclimatic conditions. Findings are expected to be applicable to other tropical carbonate platforms. [ABSTRACT FROM AUTHOR]

Global climate models often simulate atmospheric conditions incorrectly due to their coarse grid resolution, flaws in their dynamics, and biases resulting from parameterization schemes. Here we document a bias in the magnitude and extent of minimum temperature extremes in the CMIP6 model ensemble, relative to ERA5. The bias is present in the southern Cascadia region (i.e., Pacific Northwestern United States and southwestern British Columbia, Canada, spanning from the coast to the Rocky Mountains), with some models showing a bias magnitude in excess of −10°C in the first percentile of daily winter minimum temperature. The sea level pressure pattern for these events is similar in CMIP6 models and ERA5, showing high anomalies in the Northeast Pacific that are indicative of an atmospheric blocking pattern and consequently more northerly flow. Though this atmospheric blocking pattern is typically concurrent with cold winter temperatures across much of North America, Rocky and Cascade mountain ranges prevent the cold air from reaching the southern Cascadia region as confirmed by the observations and reanalysis. Our results suggest that the bias in CMIP6 minimum temperatures is a result of unresolved topography in the Rockies and Cascade mountain ranges, such that the terrain does not adequately block cold air advection from reaching the southern Cascadia region. Plain Language Summary: Global climate models continue to struggle with recreating some of the observed behaviors of our Earth system for a variety of reasons. Here we document one such issue: daily minimum temperatures in Southwestern British Columbia and western Washington that are much colder than are observed. We find that these temperatures occur when extremely cold air is moved from the north into southwestern British Columbia and western Washington. In reality, the Rocky and Cascade mountain ranges prevent this air from reaching western Washington and southwestern British Columbia by acting as barriers. However, in the global climate models these mountain ranges are lower and less jagged, making it easier for cold air to move across them. Key Points: CMIP6 models show a pronounced cold bias in the coldest daily minimum temperatures for the southern Cascadia region of North AmericaWe find no evidence suggestion that differences in large‐scale dynamics are causing the cold bias in the southern Cascadia regionPoorly resolved topography in the CMIP6 models allows excessive cold advection into southern Cascadia during atmospheric blocking events [ABSTRACT FROM AUTHOR]

This article examines the impact of glacier degradation on the Earth's rotation. By using classical mechanics and moment of inertia models, the study calculates that a loss of 200 billion tons of glaciers could result in a 1.4099×10-4 second increase in the Earth's rotation time in a year. The research aims to provide insights into the relationship between climate change and the Earth's rotation. The article acknowledges that the actual mass loss of glaciers due to global warming exceeds the assumed value, suggesting that the actual change in the Earth's rotation period may be greater. The document emphasizes the need for global attention to the accelerated mass loss of glaciers and the issue of global climate change. [Extracted from the article]

The increasing frequency of extreme weather events, such as hurricanes and rising sea levels due to climate change, presents significant challenges to coastal infrastructure. With 42% of bridges in the United States exceeding 50 years of age, which surpasses their intended service life, there is a pressing need to assess their structural integrity, especially in coastal regions. This study focuses on evaluating the structural performance of bearing pads in coastal bridges under hurricane-induced wave loadings. Utilizing a combination of physics-based models (PBM), nonlinear modal time history analysis, and numerical validation, the research examines the hysteresis response of eight distinct bearing pad configurations. The findings indicate that reinforced circular bearing pads exhibit significantly greater shear displacements compared to plain elastomeric pads, underscoring the critical influence of shape factors on shear response. Fragility functions developed in the study illustrate the probability of shear failure, with reinforced circular pads showing a 28% higher likelihood of exceedance compared to rectangular plain pads. These results highlight the necessity for advanced design methodologies specifically for bearing pads to enhance the resilience of coastal infrastructure against severe hydrodynamic forces induced by hurricanes. [ABSTRACT FROM AUTHOR]

A fundamental question in evolutionary biology concerns the relative contributions of phenotypic plasticity vs. local adaptation (genotypic specialization) in enabling wide-ranging species to inhabit diverse environmental conditions. Here, we conduct a long-term hypoxia acclimation experiment to assess the relative roles of local adaptation and plasticity in enabling highland and lowland deer mice (Peromyscus maniculatus) to sustain aerobic thermogenesis at progressively increasing elevations. We assessed the relative physiological performance capacities of highland and lowland natives as they were exposed to progressive, stepwise increases in hypoxia, simulating the gradual ascent from sea level to an elevation of 6,000 m. The final elevation of 6,000 m far exceeds the highest attainable elevations within the species' range, and therefore tests the animals' ability to tolerate levels of hypoxia that surpass the prevailing conditions within their current distributional limits. Our results demonstrate that highland natives exhibit superior thermogenic capacities at the most severe levels of hypoxia, suggesting that the species' broad fundamental niche and its ability to inhabit such a broad range of elevational zones is attributable to genetically based local adaptation, including evolved changes in plasticity. Transcriptomic and physiological measurements identify evolved changes in the acclimation response to hypoxia that contribute to the enhanced thermogenic capacity of highland natives. [ABSTRACT FROM AUTHOR]

A new dedicated coastal sea level dataset called the International Altimetry Service 2024 (IAS2024, https://doi.org/10.5281/zenodo.13208305 , Peng et al., 2024c) has been presented to monitor sea level changes along the world's coastlines. One of the reasons for generating this dataset is the quality of coastal altimeter data has been greatly improved with advanced coastal reprocessing strategies. In this study, the Seamless Combination of Multiple Retrackers (SCMR) strategy is adopted to obtain the reprocessed Jason data for January 2002 and April 2022. The evaluation results show that the data availability of the IAS2024 dataset over global coastal oceans is much higher than that of the European Space Agency Climate Change Initiative version 2.3 (ESA CCI v2.3) dataset. The closure of trend differences (0.16 ± 3.98 mm yr−1) between IAS2024 and Permanent Service for Mean Sea Level (PSMSL) tide gauge data is observed at the global scale, which further demonstrates the good performance of the IAS2024 dataset in monitoring the coastal sea level changes. The altimeter-based virtual stations have been built with the IAS2024 dataset over 0−10 km, 5−15 km and 10−20 km coastal strips, which will contribute to the analysis of coastal sea levels for the ocean community and the risk management for the policy makers. Our study also points out that no obvious variations exist in linear sea level trends from offshore to the coast in most coastal zones. In addition, the vertical land motion (VLM) estimates from the combination of coastal altimeter data with tide gauge records agree well with the University of La Rochelle 7a (ULR7a) Global Navigation Satellite System (GNSS) solution (0.09 ± 2.22 mm yr−1), suggesting that altimeter-derived VLM estimates can be an independent data source to validate the GNSS solutions. [ABSTRACT FROM AUTHOR]

Introduction: Elevation gradients are often used as a proxy for climate change as they allow comparisons of ecological responses over much larger temporal and spatial scales than is possible through experimental manipulations. Methods: Here, we tested how microarthropod communities (Collembola and Acari) are affected by climatic differences between sea level and 600 m a.s.l. on Navarino Island, in the Magellanic sub-Antarctic ecoregion of southern Chile (mean annual temperatures of 5.6 vs 3.1°C, respectively). We quantified microarthropod abundance, richness and community trait characteristics in dominant moss (Racomitrium lanuginosum and Polytrichum strictum) and lichen (Usnea trachycarpa, Pseudocyphellaria freycinetii and Stereocaulon alpinum) vegetation growing at both elevations. These moss and lichen genera are characterized by large morphological differences and allow testing of how habitat characteristics affect microarthropod community response across elevation gradients. Results: Collembola and Acari community composition differed between the low and high elevation sites. Total abundance levels of Acari were maintained in each habitat across elevation, whereas Collembola richness strongly declined (50%) at high elevation in the moss habitats. Acari community differences across elevation were driven by relative abundance changes whereas the Collembola community lost species at higher elevation. An anticipated decline of smaller eudaphic Collembola at high elevation was only observed in the moss Racomitrium, reflecting potentially lower temperature buffering capacity and shelter options compared to Polytrichum. Lichens mostly supported larger epigeic species irrespective of elevation. There were no consistent patterns linking microarthropod communities with habitat water holding capacity or water loss rates across the studied habitats and elevation. Discussion: Habitat type and the genus of moss or lichen were associated with microarthropod community changes across elevation, including examples of declines, increases and no change. These findings highlight that community responses across gradients may not always relate to the generally hypothesized environmental variables (e.g. temperature variability) and that habitat characteristics should be taken into account when using elevation as a proxy for climate change. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies aimed at assessing the variability of respiratory activity of soil microbiota (rates of basal and substrate-induced respiration), as well as of the content of organic matter carbon and microbial biomass carbon in soils formed and functioning in natural (slightly damaged) biogeocenoses along altitudinal gradient from the foothills to the high mountain regions of the Central Caucasus (500–3500 m a.s.l., Elbrus variant of altitudinal zonality, Kabardino-Balkaria). It is shown that the mean values of the studied indicators in surface horizons (0–10 and 0–20 cm, depending on the soil type) significantly increase with the altitude from mountain chernozems to subalpine mountain-meadow soils and significantly decrease at the maximum altitude in the zone of alpine mountain-meadow soils. The studied indicators in different soil types within the same altitudinal zone also differ; this difference is statistically significant (t > 2.5; p < 0.02) for most of the indicators for the compared pairs of soil types. The data obtained indicate that the impact of the altitudinal gradient is significantly transformed by additional factors. The multi-regression analysis has been performed to identify the effect of the main factors of relief (elevation above sea level and slope aspect and steepness) and climate (19 bioclimatic characteristics) on the studied indicators. It shows that the mean cumulative contribution of all 22 factors to the variation of the studied indicators is 40% in mountain chernozems, 66% in mountain-meadow chernozem-like soils, 31% in mountain meadow-steppe subalpine soils, 67% in subalpine mountain-meadow soils, and 67% in alpine mountain-meadow soils. Thus, the effect of the considered factors may significantly differ both for soils located along the altitudinal gradient and for soils functioning within the same altitudinal zone. Relief and climate play an important, but not the only, role in the formation of properties of mountainous soils in the Central Caucasus. [ABSTRACT FROM AUTHOR]

Over the last sixty ears, Singapore has expanded its land footprint over twenty-five percent by reclaiming land from the sea. Its outsized demand for sand to resource these projects has rendered regional sand markets precarious, and successive countries have banned sand exports to Singapore. Nevertheless, the Singapore government has committed to spending $SG one billion (US$ 767 million) a year until 2100 to mitigate sea level rise. While this includes a range of strategies, from improving drainage infrastructure to exploring adaptive solutions, in the main this involves reclaiming vast amounts of land from the sea to act as a bulwark against rising tides. These plans for resilience will be examined through the spectre of Long Island, a proposed project that will act as a barrier against sea level rise and incorporate nature-based solutions that are emblematic of resilience fetishism, all the while obscuring the more foundational element of this resilience, which is sand that will be obtained through granular arbitrage. [ABSTRACT FROM AUTHOR]

Purpose:Demodex infestation is a risk factor for several ocular surface diseases. However, the prevalence of ocular Demodex infection in the ultra-high altitude population is not clear. This study aimed to compare the prevalence and factors associated with Demodex in populations residing in ultra-high altitude region and sea level areas. Methods: Consecutive patients who visited Shigatse People's Hospital (> 4,000 m) and Shanghai Tongren Hospital (sea level) for eye complaints between January 2023 and January 2024 were included. Subjects were divided into ultra-high altitude and sea level groups. All subjects underwent eyelash epilation for ocular Demodex identification and counting. Demographic and lifestyle information was also collected. Results: A total of 517 subjects were eligible, including 255 subjects in the ultra-high-altitude group and 262 subjects in the sea level group. In the overall analysis, the prevalence of ocular Demodex infection was significantly different between the ultra-high-altitude and sea level groups (15.7% vs. 33.2%, P < 0.001). Multiple logistic regression showed that age, time spent outdoors, and makeup were associated with ocular Demodex infection in both groups. In addition, in the ultra-high-altitude group, people who wear sun hats outdoors were more likely to be infected with Demodex. Conclusion: The infection rate of ocular Demodex in the residents of ultra-high altitude area was significantly lower than that in the residents of sea level area, which may be related to lower ambient temperature, lower humidity, and higher solar radiation. Additionally, age, time spent outdoors, and makeup may be associated with ocular Demodex infection. [ABSTRACT FROM AUTHOR]

Understanding regional sea level variations is crucial for assessing coastal vulnerability, with accurate sea level data playing a pivotal role. Utilizing historical sea level marigrams can enhance datasets, but current digitization techniques face challenges such as bends and skews in paper charts, impacting sea level values. This study explores often‐overlooked issues during marigram digitization, focusing on the case study of Dún Laoghaire in Ireland (1925–1931). The methodology involves digitizing the original marigram trace and underlying grid to assess offsets at the nearest ft (foot) interval on the paper chart, corresponding to changes in the water level trace for each hour interval. Subtracting the digitized value from the known value (the actual measurement) allows for the determination of differences, which are then subtracted from each hourly trace value. After adjusting for offsets ranging from −3.962 to 13.716 mm (millimetres), the study improves the final accuracy of sea level data to approximately the 10 mm level. Notably, data from 1926 and 1931 exhibit modest offsets (<7 mm), while other years show more substantial offsets (>9–14 mm), emphasizing the importance of adjustments for accuracy. Such 10 mm accuracy is compatible with requirements of the Global Sea Level Observing System. Comparing the adjusted digitized data with other survey data shows similar amplitudes and phases for Dún Laoghaire in both the historical and modern datasets, and there is an overall mean sea level rise of 1.5 mm/year when combined with the available data from the Dublin region. [ABSTRACT FROM AUTHOR]

Sea level monitoring is of great significance to the life safety and daily production activities of coastal residents. In recent years, GNSS interferometric reflectometry (GNSS-IR) has gradually developed into a powerful complementary technique for sea level monitoring, with the advantages of wide signal spatial coverage and lower maintenance cost. However, GNSS-IR-retrieved sea level estimates suffer from a prominent error source, referred to as the dynamic height error due to the nonstationary sea level. In this study, the tidal analysis method, least squares method and cubic spline fitting method are used to correct the dynamic height error, and their performances are analyzed. These three methods are applied to multi-system and multi-frequency data from three coastal GNSS stations, MAYG, SC02 and TPW2, for three years, and the retrievals are compared and analyzed with the in situ measurements from co-located tide gauges to explore the applicability of the three methods. The results show that the three correction methods can effectively correct the sea level dynamic height error and improve the accuracy and reliability of the GNSS-IR sea level retrievals. The tidal analysis method shows the best correction performance, with an average reduction of 39.3% (10.7 cm) and 37.6% (6.7 cm) in RMSE at the MAYG and TPW2 stations, respectively. At station SC02, the cubic spline fitting method performs the best, with the RMSE reduced by an average of 39.3% (5.5 cm) after correction. Furthermore, the iterative process of the tidal analysis method is analyzed for the first time. We found the tidal analysis method could significantly remove the outliers and correct the dynamic height error through iterations, generally superior to the other two correction methods. With the dense preliminary GNSS-IR sea level retrievals, the smaller window length of the least squares method can yield more corrected retrievals and better correction performance. The least squares method and cubic spline fitting method, especially the former, are highly dependent on the amount of daily GNSS-IR sea level retrievals, but they are more suitable for dynamic height correction in storm events than the tidal analysis method. [ABSTRACT FROM AUTHOR]

This article discusses the archaeological implications of the discovery of the highland species Hippocamelus antisensis (Cervidae) and Vicugna vicugna (Camelidae) in two coastal contexts in the Atacama Desert (20°S, Chile). H. antisensis is currently distributed throughout the Peruvian Andes, northern Chile, western Bolivia and northwestern Argentina, between 1800 and 5500 m above sea level. V. vicugna is distributed throughout northern Peru and northwestern Argentina, in environments that exceed 3200 m above sea level. The archaeological record of deer antlers on the Atacama coast has previously been documented at the Caleta Huelén‐42 site (21°S). In the case of V. vicugna, fibers have been recovered only at the coastal site of Camarones‐14 (19°S). A dating of 4180 ± 20 year BP obtained from V. vicugna bone and indirect dating of the antlers suggest an early social exchange between groups from coastal regions and those from the Atacama Desert Mountain range, as well as encourage to the potential record of remains/products of these animals in areas far from their natural habitats. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of the proportion of coffee peel bokashi in the planting medium on the growth of papaya plant seedlings (Carica papaya L.) cv Calina. The research was conducted at the Faculty of Agriculture Screenhouse on Jalan Perjuangan, Cirebon City, at an altitude of 5 m above sea level. The research was conducted from May 2022 to June 2022. The experimental method used with a completely randomized design. The treatment consisted of 4 proportions of bokashi in the planting media, each of which was repeated 6 times so that there were 24 experimental units. Each experimental unit consisted of 10 polybags. The total papaya plant seeds used were 240 seeds. The treatments studied were: K0 = top soil, K1 = 250 g bokashi + 1 kg soil, K2 = 500 g bokashi + 1 kg soil, and K3 = 750 g bokashi + 1 kg soil. The results showed that the proportion of coffee peel waste bokashi significantly affected the growth of papaya plants. Using 500 g coffee skin waste bokashi in 1 kg of soil had the best effect on plant height, stem diameter, plant growth rate, number of leaves, root volume, root length, root ratio, and net assimilation rate. [ABSTRACT FROM AUTHOR]

Paleoreconstructions of coastal and near-coastal areas have always served as a tool towards better understanding of past, present and future geological and geomorphological processes. The reliability of paleocoastline and sea-land extent modelling is controlled by input data. Here the difference between paleoreconstructions based on present-day bathymetry and a paleotopographic elevation model are examined on the example of the Gulf of Trieste (northern Adriatic sea) - a low-gradient submerged Last Glacial Maximum alluvial plain with fairly well-resolved bathymetry and pre-transgressional paleotopography. Results presented in this study show striking differences between the spatial extent of the two modelled sets of paleocoastlines which in places exceeds tens of kilometers. These results demonstrate the importance of using an appropriate geologically-supported elevation model for paleoreconstruction as unsuitable models can result in significant errors and unreliable reconstructions. This is especially noteworthy for low-gradient settings where even a slight variation in sea level can affect vast areas. Finally, the results of this study provide insight into the Early Holocene evolution of the present-day area of the Gulf of Trieste as an abrupt and predominant northeasterly oriented transgression direction is indicated from the paleocoastline reconstructions. [ABSTRACT FROM AUTHOR]

The article examines the ecological and economic effects of the natural and anthropogenic changes occurring in the Caspian Sea and its Absheron coast. In particular, it analyzes the potential damage that fluctuations in the sea level of the Caspian could cause to tourism facilities located along the coasts of the Absheron Peninsula, as well as the significant negative effects of coastal erosion that may occur if coastal management is insufficient. The article notes that if preventive measures are not taken in time, these erosion processes could severely damage the tourism sector. The research also highlights that economic activities in the Caspian Sea, especially oil extraction and the tourism sector, could exacerbate environmental problems. Pollution and the spread of invasive species lead to a reduction in biodiversity and environmental degradation. In addition, it may adversely affect the sturgeon trade, one of Azerbaijan's main sources of income, potentially resulting in a decrease in the country's economic revenues. The transition to a green economy and the implementation of sustainable tourism strategies are presented as crucial steps in addressing these problems. The article also emphasizes the importance of regional cooperation and the adoption of sustainable environmental policies. In conclusion, interstate cooperation and the development of environmentally friendly technologies are deemed necessary to solve the Caspian Sea's ecological problems. [ABSTRACT FROM AUTHOR]

This study investigates the interannual variations in regional mean sea levels (MSLs) of the northeast Asian marginal seas (NEAMS) during August, focusing on the role of typhoon activity from 1993 to 2019. The NEAMS are connected to the Pacific through the East China Sea (ECS) and narrow, shallow straits in the east, where inflow from the southern boundary (ECS), unless balanced by eastern outflow, leads to significant convergence or divergence, as well as subsequent changes in regional MSLs. Satellite altimetry and tide-gauge data reveal that typhoon-induced Ekman transport plays a key role in MSL variability, with increased inflow raising MSLs during active typhoon seasons. In contrast, weak typhoon activity reduces inflow, resulting in lower MSLs. This study's findings have significant implications for coastal management, as the projected changes in tropical cyclone frequency and intensity due to climate change could exacerbate sea level rise and flooding risks. Coastal communities in the NEAMS region will need to prioritize enhanced flood defenses, early warning systems, and adaptive land use strategies to mitigate these risks. This is the first study to link typhoon frequency directly to NEAMS MSL variability, highlighting the critical role of wind-driven processes in regional sea level changes. [ABSTRACT FROM AUTHOR]

Rhodiola linearifolia Boriss., a perennial alpine plant from the Crassulaceae family, is renowned for its unique medicinal properties. However, existing research on this species is limited, particularly regarding the impact of altitude on its physiological and medicinal compounds. The current study employed morphophysiological and anatomical methods to explore the adaptive mechanisms of R. linearifolia across different altitudinal gradients, while also examining photosynthetic pigments and metabolomic changes. Our results indicate that despite the simultaneous effects of various mountain abiotic factors, significant correlations can be identified between altitude and trait variation. An optimal growth altitude of 2687 m above sea level was identified, which is pivotal for sustainable ecosystem management and potential species introduction strategies. It is noted that increasing altitude stress enhances the synthesis of secondary antioxidant metabolites in R. linearifolia, enhancing its pharmaceutical potential. [ABSTRACT FROM AUTHOR]

The twolined spittlebug, Prosapia bicincta (Say), is a major economic pest of forage grass and turfgrass. Prosapia bicincta was first detected in rangelands on Hawaiʻi Island in 2016 and has since spread to an estimated 72,000 ha in the North and South Kona districts. This study aimed to quantify P. bicincta abundance, plant associations, and impacts on groundcover over time. Monthly surveys of P. bicincta nymphs and adults were conducted from February 2018 to September 2022 along 17 established 100-m transects at 4 ranches located in Kona, Hawaiʻi Island, spanning an elevation gradient from 519 to 1,874 m above sea level (a.s.l.). Monitoring revealed P. bicincta occurs from 519 to 1,679 m a.s.l. primarily in Kikuyu grass (Cenchrus clandestinus (Hochst. ex Chiov.)) Morrone (Poales: Poaceae) pastures. Peaks in P. bicincta abundance coincided with the wet season, with most activity occurring from April to October and little to no activity between November and March. Mid elevation (1,000–1,300 m) transects had significantly higher mean P. bicincta abundance (126 nymphs/m2) relative to low (500–999 m) (64 nymphs/m2) and high elevations (>1,300 m) (20 nymphs/m2). Sites with the highest abundance of P. bicincta were also associated with the greatest decrease in mean grass cover (30%) and were replaced by forbs, bare ground, and shrubs. Grasses accounted for 72% of the total P. bicincta detections, with the remaining plants comprised of legumes (16%), sedges (6%), and forbs (6%). Twenty new P. bicincta plant associations were found. This information will help improve the effectiveness of management to suppress populations below economic thresholds. [ABSTRACT FROM AUTHOR]

The planned expansion of wind energy in the German Bight is creating much more densely staggered wind farms and wind farm clusters. This results in a significantly greater influence of the generated wakes on energy production of neighboring wind farms. The Dornier‐128 research aircraft operated by the Technische Universität of Braunschweig was used to measure the wind field in the lee of single and multiple wind farm clusters in the German Bight on 4 days during July 2020 and July 2021. The data at 120 m aMSL (above mean sea level) were analyzed to identify wake areas and the wind speed decrease behind the wind farm clusters. The observations were then compared to a range of numerical data including the mesoscale model Weather Research and Forecasting (WRF) applying a wind farm parameterization (WRF with wind farm parameterization [WRF‐WF]) to model wake effects and an engineering model with different setups. A model calibrated on a single wind farm is established as the baseline. A modification with a lower wake recovery, the TurbOPark model, and a WRF‐coupled model make up the three additional declinations considered. Overall, the models compared well to the measurement data in the direct vicinity of the wind farms and up to 20–30 km downstream of the wind farm clusters. The accuracy in wind speed prediction of the model results decreased with distance to the wind farms, where the mesoscale model (WRF‐WF) exhibited a more consistent performance across varying distances. [ABSTRACT FROM AUTHOR]

The nightjars of the Caprimulgus macrurus complex are distributed from Pakistan to Australia and comprise six morphologically similar but vocally distinct species. Fieldwork on Timor and Wetar, Lesser Sunda Islands, has resulted in the discovery of a seventh species in the complex, which we describe as a new species. This species has previously been confused with Caprimulgus macrurus, Caprimulgus celebensis and Caprimulgus manillensis but it differs from these and all other species in the complex by at least 13 vocal characters. Discriminant function analysis correctly classified all recordings in the complex to species. Caprimulgus ritae is known from five adult museum specimens, which are the smallest in the complex and which differ from other species in the complex in several morphological characters. A molecular phylogenetic analysis indicated that C. ritae is sister to C. meesi from Flores and Sumba, and that these species together are sister to C. macrurus. C. ritae is a tropical forest specialist occurring from sea level to at least 1500 m (probably mostly below 1000 m). Lowland and montane forests on Timor are threatened. Wetar is one of the least developed islands in Indonesia, and retains >95% natural vegetation, dominated by Eucalyptus woodlands, with tropical forests in river gorges and slopes in upland areas. Pressure for development is accelerating throughout the range of C. ritae, and a detailed assessment of its conservation status is urgently needed. [ABSTRACT FROM AUTHOR]

Leopardus wiedii and Leopardus pardalis are endangered small felids. Its main altitudinal range expands from sea level to 1,500 m. Camera traps were placed in the Matawi Indigenous Park on the Nevado de Toluca Volcano. Photographic records were obtained of L. wiedii at 3,207 masl and of L. pardalis at 3,307 masl. This is the highest altitudinal record for margay in its distribution, and for ocelot is the highest in the northern hemisphere. [ABSTRACT FROM AUTHOR]