Maximum Elevation Research Articles

Patagonian landscape modeling during Miocene to Present-day slab window formation

The subduction of seismic oceanic ridges often results in the formation of slab windows, which can affect not only the heat flow and retroarc volcanism, but also the exhumation and topographic evolution of the upper plate. An active and world-class example of a slab window is southern Patagonia, in southernmost South America, which is related to the subduction of the seismic oceanic South Chile Ridge between the middle–late Miocene and the Present day. How the subduction of the ridge and formation of the slab window have influenced the evolution of the Patagonian landscape, exhumation and topography is still under debate. Some works have proposed orogenic deformation mostly affecting the Pacific margin and hinterland areas, or an inherited early Miocene tectonic relief generated before the slab window formation. Others have preferred epeirogenesis hypotheses, such as dynamic uplift or isostatic rebound as a result of lithospheric thinning associated with asthenospheric or lithospheric mantle changes. In this work, we analyze the landscape evolution at medium (orogen-scale) and long wavelengths (embracing the whole of southern Patagonia, from coast to coast) using FastScape a landscape numerical model. This program was coupled with an optimization scheme (the Neighborhood Algorithm) suitable for nonlinear inverse problems. The “goodness” (fit to data) of our landscape evolution models was evaluated using: i) cooling ages, and ii) maximum elevations, in order to provide constraints on the uplift rates, erosion efficiency and effective elastic thickness. We then used the best values to compare two forward models representing medium- versus long-wavelength processes. Our results indicate that long-wavelength uplift geometry (including dynamic uplift and/or lithospheric rebound from thinning) involving areas from the Andes to the Atlantic coast was required from 12 Myr to the Present day in order to reproduce not only the youngest cooling ages but also Present-day topography.

Climate-Related Risk Modeling of Banana Xanthomonas Wilt Disease Incidence in the Cropland Area of Rwanda.

Banana Xanthomonas wilt (BXW) is a major threat to banana production in Rwanda, causing up to 100% yield loss. There are no biological or chemical control measures, and little is known about the potential direction and magnitude of its spread; hence, cultural control efforts are reactive rather than proactive. In this study, we assessed BXW risk under current and projected climates to guide early warning and control by applying the maximum entropy (Maxent) model on 1,022 georeferenced BXW datapoints and 20 environmental variables. We evaluated the significance of variables and mapped potential risk under current and future climates to assess spatial dynamics of the disease distribution. BXW occurrence was reliably predicted (mean validation AUC values ranging from 0.79 to 0.85). Precipitation of the coldest quarter, average maximum monthly temperature, annual precipitation, and elevation were the strongest predictors, which were responsible for 22.1, 13, 12.6, and 9.4% of the observed incidence variability, respectively, while mean temperature of the coldest quarter had the highest gain in isolation. Furthermore, the most susceptible regions (western, northern, and southern Rwanda) were characterized by elevation (1,350 to 2,000 m), annual precipitation (900 to 1,700 mm), and average temperature (14 to 20°C), among other variables, suggesting that a consistent, rainy, and warm climate is more favorable for BXW spread. Under the future climate, the risk was predicted to increase and spread to other regions. We conclude that climate change will likely exacerbate BXW-related losses of banana land area and yield under the influence of temperature and moisture. Our findings support evidence-based targeting of extension service delivery to farmers and national early warning for timely action.

Using dune restoration on an urban beach as a coastal resilience approach

Coastal dunes are globally recognized as natural features that can be important adaptation approaches for climate change along urban and natural shores. We evaluated the recovery of coastal dunes on an intensively groomed urban beach in southern California over a six-year period after grooming was discontinued. Restoration actions were minimal and included installation of three sides of perimeter sand fencing, cessation of mechanical grooming and driving, and the addition of seeds of native dune plants. To track recovery, we conducted physical and biological surveys of the restoration site and an adjacent control site (groomed beach) using metrics including sand accretion, elevation, foredune and hummock formation, vegetation recovery, and wildlife use. Sediment accretion, elevation, and geomorphic complexity increased over time in the restoration site, largely in association with sand fencing and dune vegetation. A foredune ridge (maximum elevation increase of 0.9 m) and vegetated hummocks developed, along with a general increase in elevation across the restoration site (0.3 m). After six years, an estimated total volume of approximately 1,730 m3 of sand had accreted in the restoration site and 540 m3 of sand had accreted in the foredune ridge. Over the same period, more than a meter of sediment (vertical elevation change) accumulated along the perimeter sand fencing. Groomed control areas remained flat and uniform. The total cover of vegetation in the restoration site increased over time to a maximum of approximately 7% cover by the sixth year. No vegetation was observed on the groomed control site. Native plant species formed distinct zones across the restoration site beginning by the second year and increasing over time, with dune forming species aggregating closest to the ocean in association with the incipient foredune ridge. Ecological functions observed in the restoration area included presence of dune invertebrates, shorebird roosting, and use by a breeding federally threatened shorebird, the western snowy plover (Charadrius nivosus nivosus). Our findings on geomorphic and ecological responses of a pilot dune restoration on a heavily groomed urban beach provide new insights on the opportunities and expectations for restoring dunes as nature-based solutions for climate adaptation on urban shorelines.

Efficacy and safety of intracorneal allogenic ring segment implantation in keratoconus: 1-year results.

To evaluate the safety and efficacy of corneal allogenic intrastromal ring segments in the management of keratoconus patients. The retrospective, nonrandomized, interventional case series consisted of 65 keratoconic eyes of 49 consecutive patients who had ring segment-shaped corneal allografts (KeraNatural®) implanted in intrastromal tunnels created using a femtosecond laser. The main outcome measures were uncorrected visual acuity (UCVA), corrected distant visual acuity (CDVA), refraction, keratometry, and pachymetry. Computed tomography scans of the corneal surfaces were also performed preoperatively as well as 3, 6 and 12 months postoperatively. Mean age was 29.5 ± 7.3 years (median 29, range: 20-52 years). The mean UCVA improved from 0.91 ± 0.50 logMAR preoperatively to 0.40 ± 0.24 logMAR postoperatively at 6 month follow-up (p < 0.01) and the mean CDVA improved from 0.87 ± 0.20 logMAR preoperatively to 0.27 ± 0.06 logMAR postoperatively (p < 0.01). The mean spherical equivalent improved from -8.82 ± 4.57 to -3.45 ± 4.81D (p < 0.01). Average Keratometry decreased from 49.23 ± 5.22 preoperatively to 45.63 ± 4.89 D postoperatively (p < 0.01). Mean anterior and posterior maximum elevation were also decreased significantly (p < 0.01). In one patient, dislocation of the graft towards the tunnel incision site and dehiscense at the tunnel entrance were observed in the first week of the operation. Yellow-white deposits were observed in the segment tunnels in five cases after 6 months. This study demonstrated that implantation of corneal allograft ring segments is a viable alternative treatment for keratoconus with safety and good visual results.

Comparative study of spread and vertical mooring configuration in floating collar net cage under irregular waves and current

Offshore aquaculture is one of the national strategic programs of the Ministry of Fishery and Ocean Affairs of Indonesia to increase national fish cultivation capacity. One solution is using a simple flexible floating collar net which is suitable for small to medium cage volume. In designing such floating net, its mooring line configuration is vital to maintain fixed position of structural part of the cage volume. The purpose of this study is to compare design aspect of two types of mooring systems, i.e., spread and vertical configuration, by investigating selected parameters: mooring line tension, collar offset, and volume reduction. The mooring configuration and floating collar net cage are analysed through a numerical model based on Morison-force equations, under environmental condition adopted from Kangean field East Java. Load cases from collinearly in-line and between-line directions under extreme waves and current condition are checked against relevant safety factor. The dynamics analysis using the time domain simulation is based on 900 seconds cut-off according to its maximum wave elevation profile to generate the hydrodynamics forces to the mooring systems.

ST-segment elevation myocardial infarction and the clinical significance of differentiated electrocardiogram

Aim. To evaluate the markers of changing dynamics recorded by digital processing of routine ECG using own diagnostic complex software “Smart-ECG” in patients with ST-segment elevation myocardial infarction (STEMI) based on the results of a 40-day follow-up. Materials and methods. The main group consisted of 20 patients with STEMI according to the ESC guidelines (2017) (mean age of males 56.11 ± 11.62, n = 10; mean age of females 58.22 ± 13.11, n = 10). ECG were analyzed using own developed diagnostic complex software “Smart-ECG” on the 1st, 10th, 40th day after STEMI. The first derivative of T wave – ratio of maximum velocity (MVR), inclination angle (β) and inclination height (H) of ST segment was calculated. The control group – 20 apparently healthy people. Results. MVR indicators decreased by 61.90 %, 68.20 % and 51.48 % on the 1st, 10th and 40th day, respectively, after STEMI as compared to those of the control group (p &lt; 0.01). At the moment of the maximum ST segment elevation, the height (H) of ST inclination was 347.7 % increased (p &lt; 0.01); on the 40th day, H was 25 % increased, close to control indicators, with ST segment shift to isoline (р &gt; 0.05). During the acutest period, the angle β increased by 172.2 % (p &lt; 0.01) and then decreased by 15.8 % at the recovery phase, but insignificantly. Conclusions. Self-developed medical software “Smart-ECG” for qualitative evaluation of ECG is an effective tool to diagnose pathological changes in the myocardium, makes it possible to improve the specificity, sensitivity and prognostic significance of ECG in STEMI. The significant decrease in MVR has been detected at all stages of STEMI, which was associated with a violation of electrogenesis in the repolarization phase; the critical increase in ST slope indicators (angle β and height H) on the 1st day has been found as a characteristic of ST elevation, as well as its decrease on the 40th day as a sign of reduced potential difference between healthy and damaged areas of the myocardium during the recovery stage.

Simulating the Laurentide Ice Sheet of the Last Glacial Maximum

Abstract. In the last decades, great effort has been made to reconstruct the Laurentide Ice Sheet (LIS) during the Last Glacial Maximum (LGM; ca. 21 000 years before present, 21 kyr ago). Uncertainties underlying its modelling have led to notable differences in fundamental features such as its maximum elevation, extent and total volume. As a result, the uncertainty in ice dynamics and thus in ice extent, volume and ice stream stability remains large. We herein use a higher-order three-dimensional ice sheet model to simulate the LIS under LGM boundary conditions for a number of basal friction formulations of varying complexity. Their consequences for the Laurentide ice streams, configuration, extent and volume are explicitly quantified. Total volume and ice extent generally reach a constant equilibrium value that falls close to prior LIS reconstructions. Simulations exhibit high sensitivity to the dependency of the basal shear stress on the sliding velocity. In particular, a regularised Coulomb friction formulation appears to be the best choice in terms of ice volume and ice stream realism. Pronounced differences are found when the basal friction stress is thermomechanically coupled: the base remains colder, and the LIS volume is lower than in the purely mechanical friction scenario counterpart. Thermomechanical coupling is fundamental for producing rapid ice streaming, yet it leads to a similar ice distribution overall.

Relatively large wings facilitate life at higher elevations among Nearctic dragonflies.

Determining which traits allow species to live at higher elevations is essential to understanding the forces that shape montane biodiversity. For the many animals that rely on flight for locomotion, a long-standing hypothesis is that species with relatively large wings should better persist in high-elevation environments because wings that are large relative to the body generate more lift and decrease the aerobic costs of remaining aloft. Although these biomechanical and physiological predictions have received some support in birds, other flying taxa often possess smaller wings at high elevations or no wings at all. To test if predictions about the requirements for relative wing size at high elevations are generalizable beyond birds, we conducted macroecological analyses on the altitudinal characteristics of 302 Nearctic dragonfly species. Consistent with the biomechanical and aerobic hypotheses, species with relatively larger wings live at higher elevations and have wider elevation breadths-even after controlling for a species' body size, mean thermal conditions, and range size. Moreover, a species' relative wing size had nearly as large of an impact on its maximum elevation as being adapted to the cold. Relatively large wings may be essential to high-elevation life in species that completely depend on flight for locomotion, like dragonflies or birds. With climate change forcing taxa to disperse upslope, our findings further suggest that relatively large wings could be a requirement for completely volant taxa to persist in montane habitats.

Assessment of the Feasibility of Implementing a Flash Flood Early Warning System in a Small Catchment Area

The occurrence of flash floods is an increasingly common phenomenon. In many parts of the world, it is associated with an increase in the intensity of rainfall. Reducing the financial and social losses caused by the occurrence of local urban floods is possible through the use of hydrodynamic modeling and real-time flood forecasting. The purpose of this study is to assess the ability of the modeling technique to simulate the flow in a small catchment area and to determine the time remaining to reach the set warning and danger levels. SWMM 5.2 and QuantumGIS software were used in the study. The analysis showed that for the considered catchment area with a short length of the main stream (1612 m), the time possible for implementing countermeasures and evacuating the population is 70 to 120 min. The study also confirmed that short-term rainfall requires less depth to reach high stormwater elevations than long-term rainfall. In addition, a relationship was noted between the preceding rainfall and the height of stormwater and the forecast time. There was an unfavorable reduction in forecasting time as the depth of rainfall increased and its duration shortened. In the case of the analyzed catchment, the maximum elevation of stormwater (Esw,max) is generated by rainfall that is characterized by the highest intensity in the final phase of their duration. Similarly, the longest forecast time (tf) for the maximum stormwater elevation is caused by rainfall, which is characterized by the highest intensity in its final phase. The results of the study can significantly assist local governments when developing a catchment management plan and when trying to implement practices to minimize the negative effects of flash floods.

River blockage and impulse wave evolution of the Baige landslide in October 2018: Insights from coupled DEM-CFD analyses

On 11 October 2018, the Baige landslide in Southwest China blocked the Jinsha River and induced waves amplifying the landslide-affected area significantly. Devastating flood damage was caused by the consequent dam breach. Such a complex sequence can lead to catastrophic consequences but has rarely been fully reproduced. This paper investigates the landslide-river interaction of the first Baige landslide based on coupled discrete element method (DEM) and computational fluid dynamics (CFD) analyses. To this end, the volume of fluid (VOF) and virtual sphere model are adopted to realise impacted river tracing and accurate terrain modelling. The damming process and impulse wave evolution of the first event are well represented. In addition, the simulated cumulative landslide spreading path, deposit geometry, maximum wave elevation and cumulative wave erosion area satisfactorily match the survey results. Our findings further indicate that the movement path and deposit morphology of the Baige landslide are mainly affected by local terrain, while the propagation of impulse waves is driven by the sliding mass and modulated by the riverbank and hydrodynamic conditions. In particular, we discussed the evolution patterns of impulse waves caused by river damming landslides, encompassing run-up on the opposite bank and quasi-3D propagation along the river direction. This research provides a valuable guide for the practical simulation of river blockage and impulse wave evolution and supports the mitigation of landslide disasters in mountainous areas.

Development of Novel Balloon-Integrated Optical Catheter for Endoscopic and Circumferential Laser Application.

The current study aims to demonstrate the feasibility of a novel balloon-integrated optical catheter (BIOC) to achieve endoscopic laser application for circumferential coagulation of a tubular tissue structure. Both optical and thermal numerical simulations were developed to predict the propagation of laser light and a spatio-temporal distribution of temperature in tissue. Ex vivo esophagus tissue was tested with 980nm laser light at 30 W for 90s for quantitative evaluations. In vivo porcine models were used to validate the performance of BIOC for circumferential and endoscopic laser coagulation of esophagus in terms of acute tissue responses post-irradiation. Optical simulations confirmed that a diffusing applicator was able to generate a circumferential light distribution in a tubular tissue structure. Both numerical and experimental results presented that the maximum temperature elevation occurred at 3-5mm (muscle layer) below the mucosa surface after 90 s irradiation. In vivo tests confirmed the circumferential delivery of laser light to a deep muscle layer as well as no evidence of thermal damage to the esophageal mucosa. The proposed BIOC can be a feasible optical device to provide circumferential laser irradiation as well as endoscopic coagulation of tubular esophagus tissue for clinical applications.

Investigating the Capability of HEC-RAS Model for Tsunami Simulation

This study highlights the simulation of tsunami cases using HEC-RAS 6.1. The primary aim is to evaluate the capability of the software in performing tsunami simulation due to its standalone computational framework (pre-processing, execution, and post-processing stages), making the modeling process interactive. The model accuracy was tested against some benchmark cases of wave propagation, including analytical solutions, laboratory experiments, and field measurements. The results showed HEC-RAS was capable of modeling tsunami propagation. The maximum elevation and velocity magnitude were accurately computed for the analytical cases. Furthermore, sufficiently accurate results were obtained for the laboratory case, where the maximum elevation was properly computed. For the field cases, the wave arrival time and the fluctuations of water surface and velocity were appropriately calculated. The Root Mean Square Error values between the numerical results and the analytical/observed data were relatively low below 30%, with the Pearson Product Moment Correlation values ranging from 52–99%. In addition to its eminence, a drawback was found regarding the graphical user interface (GUI) of HEC-RAS for the input of boundary conditions. These findings will be beneficial for the coastal engineering community and the continuous development of HEC-RAS.&#x0D;

Development of a Swellable and Floating Gastroretentive Drug Delivery System (sfGRDDS) of Ciprofloxacin Hydrochloride.

Sangelose® (SGL) is a novel hydroxypropyl methylcellulose (HPMC) derivative that has been hydrophobically modified. Due to its high viscosity, SGL has the potential as a gel-forming and release-rate-controlled material for application in swellable and floating gastroretentive drug delivery systems (sfGRDDS). The aim of this study was to develop ciprofloxacin (CIP)-loaded sfGRDDS tablets comprised of SGL and HPMC in order to extend CIP exposure in the body and achieve optimal antibiotic treatment regimes. Results illustrated that SGL-HPMC-based sfGRDDS could swell to a diameter above 11 mm and showed a short floating lag time (<4 s) and long total floating time (>24 h) to prevent gastric emptying. In dissolution studies, CIP-loaded SGL-HPMC sfGRDDS demonstrated a specific biphasic release effect. Among the formulations, the SGL/type-K HPMC 15,000 cps (HPMC 15K) (50:50) group exhibited typical biphasic release profiles, with F4-CIP and F10-CIP individually releasing 72.36% and 64.14% CIP within 2 h dissolution, and sustaining release to 12 h. In pharmacokinetic studies, the SGL-HPMC-based sfGRDDS demonstrated higher Cmax (1.56-1.73 fold) and shorter Tmax (0.67 fold) than HPMC-based sfGRDDS. Furthermore, SGL 90L in GRDDS indicated an excellent biphasic release effect and a maximum elevation of relative bioavailability (3.87 fold). This study successfully combined SGL and HPMC to manufacture sfGRDDS that retain CIP in the stomach for an optimal duration while improving its pharmacokinetic characteristics. It was concluded that the SGL-HPMC-based sfGRDDS is a promising biphasic antibiotic delivery system that can both rapidly achieve the therapeutic antibiotic concentration and maintain the plasma antibiotic concentration for an extended period to maximize antibiotic exposure in the body.

Nieuwerkerk - Emperor of China (NEC) Seamounts (Banda Sea): A multibeam seafloor imagery analysis

A new multibeam dataset of Nieuwerkerk and Emperor of China (NEC) seamounts was acquired during the Jalacitra 2-2022 ”Banda” Expedition in the Banda Sea region. This study discusses a morphometric analysis of the seamounts based on a high-resolution bathymetry digital elevation model (DEM) and describes the morphometric features, namely: slope, profile curvature, and aspect. Morphological results indicate that the Nieuwerkerk seamount has an area of 2,416 km2 with a maximum peak elevation of approximately 3,460 m above the seabed and 357 m below the water surface. In the southwest of the Nieuwerkerk seamount, two new seamounts were discovered, which are still unnamed and seem morphologically connected to the Nieuwerkerk seamount. Each of the seamounts covers an area of 148 km2 and 220 km2, respectively, with a maximum peak elevation of approximately 2,338 m and 2,053 m above the seabed. Additionally, both seamounts have an elevation of 1,878 m and 2,017 m below the sea surface. Meanwhile, the Emperor of China seamount is located southwest of the three formerly mentioned seamounts, with the maximum peak seats at 2,165 m below the sea surface. Seamount C is located in the west of the surveyed area and it covers an area of 95.6 km2 with an elevation of 1,834 m above the seabed. The results of regression analysis indicate that all of the features could be used for the morphological classification.

Last Glacial Maximum and subsequent glacial chronology in the monsoon-dominated Sikkim Himalaya, India

The study investigates sequential evolution of glacial-landforms in relation to paleo-climate by establishing glacial chronology in Zemu and East-Rathong Glaciers valleys, Sikkim, Eastern Himalaya during the Late-Quaternary. This region is dominated by the Indian summer monsoon, followed by winter rain from the NE-monsoon and Westerlies which influence the glaciers. The study relies on field-based geomorphological mapping and geospatial datasets. The Toe-to-Headwall Altitude Ratio, Toe-to-Summit Altitude Method, and Maximum Elevation of Lateral Moraines methods have been used to calculate the equilibrium line altitudes (ELA) to assess magnitudes of glacial changes over time. OSL dating is used to assess the timing of glacial stages. Additionally, a comparison is made with ELA changes, the distance of moraines from the present glacier snouts, and established glacial chronologies in neighboring areas. The existing landscape depicts the dominant role of the region's present and past glacial processes. The region is also modified by periglacial, paraglacial, and fluvial processes. Four glacial stages have been identified in the region during the late-Quaternary period, contemporaneous to the Last Glacial Maximum, Younger Dryas, Late-Holocene, and Little Ice Age. The first stage (Sikkim-I), marked by dissected trimlines up to ∼16 km downstream, appears to belong to the global Last Glacial Maximum and dated to ∼18.276 ± 0.589 ka with a change of −519.5 m and − 3.4 °C in ELAs and temperature, respectively. The second stage, Sikkim-II is represented by lateral moraines running up to ∼5 km downstream in U-shaped valleys and seems to coincides with the Younger Dryas with ELAs depression of −261.8 m along with a − 1.7 °C drop in temperature. The third Stage (Sikkim-III), marked by small pairs of stable lateral moraines covered with shrubs within ∼3 km downstream, probably belongs to the late Holocene when ELAs and temperature dropped by −177.3 m and − 1.2 °C, respectively. The fourth stage (Sikkim-IV) is notified by a dumped heap of end moraines within ∼2 km downstream, possibly occurred during the LIA with a depression of −72.4 m in ELAs and − 0.5 °C in temperature. These glacial stages are synchronous with the glaciations in the neighboring regions of Thangu in north-Sikkim, Bhutan, and eastern Himalaya syntax. However, the findings of the study differ from the westerly dominated NW Himalayas, broadly.

Three-years outcomes of simultaneous photorefractive surgery and customized corneal cross-linking for keratoconus.

To report the efficacy of customized cross-linking (CXL) in halting progression of keratoconus when combined with photorefractive procedures. Seven eyes from 7 patients with documented progressive keratoconus were treated with customized CXL (customized ultraviolet-A irradiance pattern centered on the maximum posterior elevation with total energy levels ranging from 5.4 up to 10J/cm2 , and an energy fluence of 9mW/cm2) combined with photorefractive procedures. Four patients underwent simultaneous transepithelial photorefractive keratectomy (T-PRK) plus customized CXL, and three patients underwent simultaneous transepithelial phototherapeutic keratectomy (T-PTK) plus customized CXL. Tomographic parameters (Kmax, pachymetry of the thinnest point and maximal elevation of posterior float and regularization index) and best spectacle-corrected visual acuity (BSCVA) were compared preoperatively and 3years postoperatively. All eyes showed a decrease in the maximal curvature Kmax, and none of eyes showed progression. Six eyes showed a flattening of 3 or more diopters (D). On average, Kmax decreased by - 4.8 ± 2.5 D, and the BSCVA improved by 0.04 ± 0.07 logarithm of the minimal angle of resolution. The mean value of regularization index was 8.7 ± 3.8 D. Mild corneal haze occurred in two eyes, and superficial apical scar occurred in one eye. None of the eyes had a vision-threatening complication. Customized CXL combined with photorefractive procedure (T-PRK/T-PTK) resulted in long lasting flattening effect and strong regularization of keratoconic corneas along with improvement of BSCVA over a 3-year follow-up.

The effects of atmospheric dust and solar radiation on the dayside ionosphere of Mars derived from 17 years of Mars Express radio science observations

This work combines 17 years of Mars Express radio science (MaRS) observations with proxies for insolation and local/global atmospheric dust to investigate the combined and individual effects on the dayside ionosphere of Mars from the top down to the ionospheric base.The increase in insolation from orbital apocenter to pericenter in combination with Mars‘ dust cycle causes an average rise of the whole photochemically dominated region of the dayside ionosphere, ranging from 13 km at the ionospheric base up to 22 km above the main peak during conditions without a global dust storm. The declining phase of the 2018 global dust storm was observed by MaRS on the southern hemisphere and close to pericenter. The observed lifting effect on the whole photochemically dominated region of the ionosphere from the increased insolation and the high local and global atmospheric dust levels exceeds that seen by MaRS from similar seasons during years without a global dust storm.The average ionospheric peak altitude at the subsolar point rises for increasing levels of local atmospheric dust until a maximum elevation is reached. This maximum depends on the available insolation at the top of the planetary atmosphere. Further increases of the local atmospheric dust levels do not lead to a further rise of the average ionospheric peak altitude in the investigated data set. This indicates a limit for the warming/expansion of the lower neutral atmosphere and the consecutive lifting of the ionosphere based on the available insolation and explains why regional dust storms can cause a similar lifting of the ionospheric main peak region as global dust storms.

Efficient Probabilistic Prediction and Uncertainty Quantification of Tropical Cyclone–Driven Storm Tides and Inundation

Abstract This study proposes and assesses a methodology to obtain high-quality probabilistic predictions and uncertainty information of near-landfall tropical cyclone–driven (TC-driven) storm tide and inundation with limited time and resources. Forecasts of TC track, intensity, and size are perturbed according to quasi-random Korobov sequences of historical forecast errors with assumed Gaussian and uniform statistical distributions. These perturbations are run in an ensemble of hydrodynamic storm tide model simulations. The resulting set of maximum water surface elevations are dimensionality reduced using Karhunen–Loève expansions and then used as a training set to develop a polynomial chaos (PC) surrogate model from which global sensitivities and probabilistic predictions can be extracted. The maximum water surface elevation is extrapolated over dry points incorporating energy head loss with distance to properly train the surrogate for predicting inundation. We find that the surrogate constructed with third-order PCs using elastic net penalized regression with leave-one-out cross validation provides the most robust fit across training and test sets. Probabilistic predictions of maximum water surface elevation and inundation area by the surrogate model at 48-h lead time for three past U.S. landfalling hurricanes (Irma in 2017, Florence in 2018, and Laura in 2020) are found to be reliable when compared to best track hindcast simulation results, even when trained with as few as 19 samples. The maximum water surface elevation is most sensitive to perpendicular track-offset errors for all three storms. Laura is also highly sensitive to storm size and has the least reliable prediction. Significance Statement The purpose of this study is to develop and evaluate a methodology that can be used to provide high-quality probabilistic predictions of hurricane-induced storm tide and inundation with limited time and resources. This is important for emergency management purposes during or after the landfall of hurricanes. Our results show that sampling forecast errors using quasi-random sequences combined with machine learning techniques that fit polynomial functions to the data are well suited to this task. The polynomial functions also have the benefit of producing exact sensitivity indices of storm tide and inundation to the forecasted hurricane properties such as path, intensity, and size, which can be used for uncertainty estimation. The code implementing the presented methodology is publicly available on GitHub.

Spatially estimating flooding depths from damage reports

It is important that a sustainable community better prepare for and design mitigation processes for major flooding events, particularly as the climate is non-stationary. In recent years, there have been major storm events in the USA with record amounts of rainfall that some refer to as stalled storms. These stalled storms frequently result in flooding of urban areas which are not subject to riverine or storm surge flooding. This research focuses on using flood damage reports in conjunction with contour maps, geographical information systems, Light Detection and Ranging (LiDAR) data, photographs, and spatial averaging to develop total (high) flood elevation data sets for two neighborhoods for Tropical Storm Imelda in Beaumont, Texas. When various sources of data such as insurance or Federal Emergency Management Agency damage reports, updated LiDAR elevation sets, and coordination data are readily available, this may be an economical method of estimating maximum flood elevations. High-water marks are frequently collected by various agencies as soon as possible after a flooding event, but these data sets might provide even additional information and validation many months or years post an event.

Hydrogeological origin of the CO2-rich mineral water of Vilajuïga in the Eastern Pyrenees (NE Catalonia, Spain)

The mineral water of Vilajuïga village in Alt Empordà (NE Catalonia, Spain) owes its uniqueness to an emanation of geogenic CO2 that modifies groundwater hydrochemistry to produce a differentiated HCO3–Na- and CO2-rich groundwater among the usual Ca–HCO3 type found in this region. A hydrogeological conceptual model attributes its occurrence to the intersection of two faults: La Valleta and Garriguella-Roses. The former provides a thrust of metamorphic over igneous rocks, formed during the Paleozoic, over a layer of ampelitic shale that, from a hydrogeological perspective, acts as a confining layer. The Garriguella-Roses normal fault, which originated during the Neogene, permits the degassing of geogenic CO2 that is attributed to volcanic activity occurring in the Neogene. Groundwater mixing from the metamorphic and igneous rock units plus the local occurrence of CO2 creates a HCO3–Na water that still holds free-CO2 in solution. Interaction with the gas phase is restricted at the intersection of the two faults. Radiocarbon dating, after correcting for geogenic dead carbon, estimates an age of 8,000 years BP. The low tritium content (0.7 TU) indicates that Vilajuïga water is a mix of “older” groundwater recharged in the metamorphic rocks of the Albera range and “younger” groundwater from the igneous rocks of the Rodes range, over a recharge area of 45 km2 and a maximum elevation of 600 m. Given its origin as rare groundwater in the southern slope of the Eastern Pyrenees, purposeful monitoring is necessary to evaluate the groundwater vulnerability and anticipate impacts from nearby wells and climate-change effects.