Large Water Bodies Research Articles

Satellite-based remote sensing data set of global surface water storage change from 1992 to 2018

Abstract. The recent availability of freely and openly available satellite remote sensing products has enabled the implementation of global surface water monitoring at a level not previously possible. Here we present a global set of satellite-derived time series of surface water storage variations for lakes and reservoirs for a period that covers the satellite altimetry era. Our goals are to promote the use of satellite-derived products for the study of large inland water bodies and to set the stage for the expected availability of products from the Surface Water and Ocean Topography (SWOT) mission, which will vastly expand the spatial coverage of such products, expected from 2021 on. Our general strategy is to estimate global surface water storage changes (ΔV) in large lakes and reservoirs using a combination of paired water surface elevation (WSE) and water surface area (WSA) extent products. Specifically, we use data produced by multiple satellite altimetry missions (TOPEX/Poseidon, Jason-1, Jason-2, Jason-3, and Envisat) from 1992 on, with surface extent estimated from Terra/Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) from 2000 on. We leverage relationships between elevation and surface area (i.e., hypsometry) to produce estimates of ΔV even during periods when either of the variables was not available. This approach is successful provided that there are strong relationships between the two variables during an overlapping period. Our target is to produce time series of ΔV as well as of WSE and WSA for a set of 347 lakes and reservoirs globally for the 1992–2018 period. The data sets presented and their respective algorithm theoretical basis documents are publicly available and distributed via the Physical Oceanography Distributed Active Archive Center (PO DAAC; https://podaac.jpl.nasa.gov/, last access: 13 May 2020) of NASA's Jet Propulsion Laboratory. Specifically, the WSE data set is available at https://doi.org/10.5067/UCLRS-GREV2 (Birkett et al., 2019), the WSA data set is available at https://doi.org/10.5067/UCLRS-AREV2 (Khandelwal and Kumar, 2019), and the ΔV data set is available at https://doi.org/10.5067/UCLRS-STOV2 (Tortini et al., 2019). The records we describe represent the most complete global surface water time series available from the launch of TOPEX/Poseidon in 1992 (beginning of the satellite altimetry era) to the near present. The production of long-term, consistent, and calibrated records of surface water cycle variables such as in the data set presented here is of fundamental importance to baseline future SWOT products.

EDTA-Inspired Polydentate Hydrogels with Exceptionally High Heavy Metal Adsorption Capacity as Reusable Adsorbents for Wastewater Purification.

Water pollution by heavy metal ions is a critical threat to public health. To remove the heavy metal pollutants from large waterbodies, we have synthesized a biocompatible, cost-effective, metal ion non-specific, and ethylenediaminetetraacetic acid (EDTA)-inspired polydentate hydrogel with exceptionally high adsorption capacity and reusability. The hydrogel was synthesized by the transamidation reaction between hydrolyzed polyacrylamide and branched polyethylenimine (BPEI). The mechanical strength of the synthesized hydrogel displayed an increasing trend with the wt % of the cross-linker (BPEI) and achieved a maximum storage modulus (Gmax') of 1093 Pa. Scanning electron microscopy revealed a porous network structure of the hydrogel (pore size: 30-70 μm), resulting in a very high swelling ratio of 5800%. The porous hydrogel manifested the maximum adsorption capacity of 482.2 mg/g when adsorbing from a mixture of metal ions (Cr3+, Cu2+, Zn2+, Cd2+, Hg2+, and Pb2+), higher than any EDTA-grafted material known to date. The high adsorption capacity of the hydrogel was attributed to the existence of numerous EDTA-mimicking coordinating functional groups, as confirmed by X-ray photoelectron spectroscopy. In addition, the hydrogel showed the self-healing property and preserved more than 85% adsorption efficiency even after five cycles of reuse. Furthermore, the hydrogels showed no or moderate toxicity toward mammalian cells.

Site Selection

Site selection for citrus production involves multiple critical factors, with freeze susceptibility being paramount, particularly in Florida. Latitude generally correlates with warmer conditions, making southern locations preferable. Proximity to heat sources like large bodies of water and consideration of topography also influence site warmth during freezes. Soil quality is another major factor; well-drained, relatively fertile soils with sufficient clay and organic matter are ideal, though much of Florida's soil requires modification for optimal citrus growth. Water management is crucial due to issues with both excess water removal and irrigation needs, compounded by regulatory and quality concerns. Economic factors, including land value, taxes, and access to infrastructure, further impact site viability. A thorough assessment of these factors is essential to ensure long-term productivity and profitability in citrus cultivation. First published June, 1992.

Performance evaluation of road surface temperature forecasts

This paper describes a study focusing on performance evaluation of road weather information system (RWIS) surface temperature forecasts. To identify the factors influencing the accuracy of forecasts, five research hypotheses regarding climate patterns, geographical attributes, seasonal variations, time of day, and forecast horizon are proposed. Observation and forecast data were provided by four North American provinces, and were processed and stratified by station, hour, and month to quantify their effects. The findings based on two statistical measures; namely, mean absolute error and percent of acceptable forecasts suggested that the maritime climate group had the highest correspondence while the mixed climate group had the lowest. The geographical attributes showed that the forecasting performance of coastal maritime regions was found to have a negative correlation to the distance from nearby large bodies of water. Forecasts for the daytime were found to be less accurate than for the nighttime and deteriorate quickly as the forecasting horizon increased.

Land use regression modeling of microscale urban air temperatures in greater Vancouver, Canada

BackgroundExtreme heat events have been associated with excess morbidity and mortality worldwide. Previous research mainly evaluated extreme heat exposures at the municipal and local scales, but individuals are exposed in much smaller areas. The goal of this study was to assess whether land use regression (LUR) models could be developed for air temperature using measurements collected by a pedestrian. MethodsMicroscale air temperature (<100 m) was measured during 42 sampling runs across 20 routes in greater Vancouver, Canada. Six independent variables were considered as potential predictors for LUR model construction for each run and for greater Vancouver as a whole. All models were evaluated using a spatial leave-ten-out cross-validation (LTOCV) approach. ResultsThe most predictive LUR variables were Distance to Large Water Body, Distance to Major Road, Normalized Difference Water Index (NDWI), and Sky-View Factor (SVF). On average, the best individual route models explained 39% of the variation in microscale air temperatures for the 20 routes. The overall model explained only 10% of the variation in the 20 combined routes. ConclusionMobile air temperatures were associated with geographic and built environment features at the microscale. The collected data were used to build moderately predictive LUR models for some locations, but could not be used to successfully model the entire study area.

Water Monitoring System using Unmanned Surface Vehicle

In today’s world where climate activists focus more on large water bodies like seas and oceans, many smaller water bodies which lie neglected are also being contaminated. These smaller bodies also affect the groundwater, which goes unnoticed. The system checks parameters such as turbidity, temperature and pH levels. In addition to these monitoring, the depth of the water is measured to check whether any unnoticed large dumping/deposition had occurred. It is integrated on a USV so that human intervention is minimized. This system aims to provide continuous quality surveillance of water in places where large scale monitoring is not feasible, with the help of LoRa Communication which ensures low energy consumption and easier to implement compared to IoT technology. It can be implemented in rural as well as urban water bodies to check whether the quality of water has deviated from regular levels due to any external factors.

The role of physical geographic parameters affecting past (1980–2010) and future (2020–2049) thermal stress in Iran

In this study, the wet-bulb globe temperature (WBGT) validated biometeorological index is used to monitor and project future human thermal stress in Iran. The meteorological components required to calculate this index include dry and wet temperatures, relative humidity and radiation. To monitor and project thermal stress, data for two time periods are used: (i) baseline data for the period 1980–2010 and (ii) Can-ESM2 model outputs from the CMIP5 model series, which projects values for the period 2020–2049. Four physical geographic factors are used for modeling WBGT frequency; these include station height (elevation), distance from nearest large water body, latitude and longitude. To establish the role of these components on WBGT extreme values, a weighted geographical regression method is used. Findings show that by considering these variables in the form of multivariate weighted regressions, WBGT threshold values are reliably modeled. Based on projected global warming scenarios in coming decades, the threshold of thermal stress occurrence for most regions of Iran shows larger values than those for the reference period. Parameters of latitude, longitude and distance from a large water body will have an incremental impact as contributors to the occurrence of future thermal stress, relative to the reference period. Of these, latitude will have the greatest impact on thermal stress (6.3%), while that for longitude and distance from a large water body will be 2.4% and 1.4%, respectively. However, station elevation will have a reduced impact on thermal stress (by 4.1%).

Evaluation of a new 18-year MODIS-derived surface water fraction dataset for constructing Mediterranean wetland open surface water dynamics

Wetlands are among the most biodiverse ecosystems in the world, due largely to their dynamic hydrology. Frequent observations by satellite sensors such as the Moderate Resolution Imaging Spectrometer (MODIS) allow for monitoring the seasonal, inter-annual and long-term dynamics of surface water extent. However, existing MODIS-based studies have only demonstrated this for large water bodies (>100 km2) despite the ecological importance of smaller-sized wetland systems. In this paper, we assessed if the temporal dynamics of surface water extent can be effectively captured with MODIS for a wide range of water body sizes, specifically 0.01 km2 and larger. We constructed the temporal dynamics of surface water extent for 340 individual water bodies in the Mediterranean region between 2000 and 2017, using a previously developed 8-day 500 m MODIS surface water fraction (SWF) dataset. We then evaluated how MODIS SWF time series corresponded to water extent derived from a Landsat-based dataset and to satellite-altimetry derived water level data. Results showed that although correlations between MODIS- and Landsat-derived SWF were poor for relative static water bodies (r = 0.17), they increased for more dynamic water bodies (r = 0.81). For dynamic water bodies>100 km2, time series of water extent derived from MODIS SWF showed good correlation with both Landsat (r ≥ 0.76) and water level data (ρ ≥ 0.63). Our MODIS SWF dataset can also effectively monitor the variability of very small water bodies (<1 km2) when comparing with Landsat data as long as the temporal variability in their surface water area was high. We conclude that MODIS SWF is a useful product to help understand hydrological dynamics for both small and larger-sized water bodies, and to monitor their seasonal, intermittent, inter-annual and long-term changes.

The gateway to Africa: What determines sea crossing performance of a migratory soaring bird at the Strait of Gibraltar?

Large bodies of water represent major obstacles for the migration of soaring birds because thermal updrafts are absent or weak over water. Soaring birds are known to time their water crossings with favourable weather conditions and there are records of birds falling into the water and drowning in large numbers. However, it is still unclear how environmental factors, individual traits and trajectory choices affect their water crossing performance, this being important to understand the fitness consequences of water barriers for this group of birds. We addressed this problem using the black kite Milvus migrans as model species at a major migration bottleneck, the Strait of Gibraltar. We recorded high-resolution GPS and triaxial accelerometer data for 73 birds while crossing the Strait of Gibraltar, allowing the determination of sea crossing duration, length, altitude, speed and tortuosity, the flapping behaviour of birds and their failed crossing attempts. These parameters were modelled against wind speed and direction, time of the day, solar irradiance (proxy of thermal uplift), starting altitude and distance to Morocco, and age and sex of birds. We found that sea crossing performance of black kites is driven by their age, the wind conditions, the starting altitude and distance to Morocco. Young birds made longer sea crossings and reached lower altitude above the sea than adults. Crosswinds promoted longer sea crossings, with birds reaching lower altitudes and with higher flapping effort. Birds starting at lower altitudes were more likely to quit or made higher flapping effort to complete the crossing. The location where birds started the sea crossings impacted crossing distance and duration. We present evidence that explains why migrating soaring birds accumulate at sea passages during adverse weather conditions. Strong crosswinds during sea crossings force birds to extended flap-powered flight at low altitude, which may increase their chances of falling in the water. We also showed that juvenile birds assume more risks than adults. Finally, the way in which birds start the sea crossing is crucial for their success, particularly the starting altitude, which dictates how far birds can reach with reduced flapping effort.

Impact of an Irrigation Dam on the Transmission and Diversity of Plasmodium falciparum in a Seasonal Malaria Transmission Area of Northern Ghana.

Water bodies such as dams are known to alter the local transmission patterns of a number of infectious diseases, especially those transmitted by insects and other arthropod vectors. The impact of an irrigation dam on submicroscopic asexual parasite carriage in individuals living in a seasonal malaria transmission area of northern Ghana was investigated. A total of 288 archived DNA samples from two cross-sectional surveys in two communities in the Bongo District of Northern Ghana were analysed. Parasite density was determined by light microscopy and PCR, and parasite diversity was assessed by genotyping of the polymorphic Plasmodium falciparum msp2 block-3 region. Submicroscopic parasitaemia was estimated as the proportional difference between positive samples identified by PCR and microscopy. Dry season submicroscopic parasite prevalence was significantly higher (71.0%, p=0.013) at the dam site compared with the nondam site (49.2%). Similarly, wet season submicroscopic parasite prevalence was significantly higher at the dam site (54.5%, p=0.008) compared with the nondam site (33.0%). There was no difference in parasite density between sites in the dry season (p=0.90) and in the wet season (p=0.85). Multiplicity of infection (MOI) based on PCR data was significantly higher at the dam site compared with the nondam site during the dry season (p < 0.0001) but similar between sites during the wet season. MOI at the nondam site was significantly higher in the wet season than in the dry season (2.49, 1.26, p < 0.0001) but similar between seasons at the dam site. Multivariate analysis showed higher odds of carrying submicroscopic parasites at the dam site in both dry season (OR = 7.46, 95% CI = 3.07–18.15) and in wet season (OR = 1.73, 95% CI = 1.04–2.86). The study findings suggest that large water bodies impact year-round carriage of submicroscopic parasites and sustain Plasmodium transmission.

Improving the Estimation of Water Level over Freshwater Ice Cover using Altimetry Satellite Active and Passive Observations

Owing to its temporal resolution of 10-day and its polar orbit allowing several crossings over large lakes, the US National Aeronautics and Space Administration (NASA) and the French Centre National d’Etudes Spatiales (CNES) missions including Topex/Poseidon, Jason-1/2/3 demonstrated strong capabilities for the continuous and long-term monitoring (starting in 1992) of large and medium-sized water bodies. However, the presence of heterogeneous targets in the altimeter footprint, such as ice cover in boreal areas, remains a major issue to obtain estimates of water level over subarctic lakes of similar accuracy as over other inland water bodies using satellite altimetry (i.e., R ≥ 0.9 and RMSE ≤ 10 to 20 cm when compared to in-situ water stages). In this study, we aim to automatically identify the Jason-2 altimetry measurements corresponding to open water, ice and transition (water-ice) to improve the estimations of water level during freeze and thaw periods using only the point measurements of open water. Four Canadian lakes were selected to analyze active (waveform parameters) and passive (brightness temperature) microwave data acquired by the Jason-2 radar altimetry mission: Great Slave Lake, Lake Athabasca, Lake Winnipeg, and Lake of the Woods. To determine lake surface states, backscattering coefficient and peakiness at Ku-band derived from the radar altimeter waveform and brightness temperature at 18.7 and 37 GHz measured by the microwave radiometer contained in the geophysical data records (GDR) of Jason-2 were used in two different unsupervised classification techniques to define the thresholds of discrimination between open water and ice measurements. K-means technique provided better results than hierarchical clustering based upon silhouette criteria and the Calinski-Harabz index. Thresholds of discrimination between ice and water were validated with the Normalized Difference Snow Index (NDSI) snow cover products of the MODIS satellite. The use of open water threshold resulted in improved water level estimation compared to in situ water stages, especially in the presence of ice. For the four lakes, the Pearson coefficient (r) increased on average from about 0.8 without the use of the thresholds to more than 0.90. The unbiased RMSE were generally lower than 20 cm when the threshold of open water was used and more than 22 cm over smaller lakes, without using the thresholds.

Seasonal Seismicity in the Western Branch of the East African Rift System

AbstractSurface load variations from large water bodies alter the state of stress on faults and potentially affect earthquake nucleation processes. We report observational evidence for seasonal variations of seismicity on the border faults of the western branch in the East African Rift System. Relying on water level changes of Lake Victoria and the surrounding rift lakes and soil moisture from the Global Land Data Assimilation System model, we calculate the crustal stress changes using a finite element model. Our results suggest the seasonal hydrological variations produce a 0.2–0.8 kPa Coulomb stress change on the border faults. The primary annual peak in seismicity is coincident with the peak Coulomb stress with an insignificant time lag. The correlation suggests seasonal variations of seismicity rates in the western branch of East African Rift System are modulated by the hydrological loading from Lake Victoria and the large rift lakes in the surrounding region.

Reconstruction of the Climate of the Medieval Epoch Based on Soil and Geochemical Studies of Kurgans of the Srostki Culture in the South of Western Siberia

The environmental diversity of Altai region is of great interest for researchers. There are many monuments of cultural heritage in the region, which are still poorly studied by natural scientific methods. Paleosols and background soils of the large Srostki-I necropolis of the Early Medieval epoch was examined by pedological and geochemical methods with the aim to trace changes in the soil properties over time and to apply these data for reconstruction of the paleoclimate. This group of kurgans is located in Biysk district of the Altai region and, according to the radiocarbon method, dates back to 890 ± 105 – 975 ± 85 AD (calibration 1δ). Paleosols of the Medieval epoch are characterized by a weaker leaching of carbonates in the middle part of the profile, lower accumulation of biophilous elements (P, S, Co) in the upper horizons, and lower values of the weathering index Al₂O₃/(CaO + MgO + Na₂O + K₂O) in comparison with the background surface soils. Thus, in the period before the kurgans’ construction, these paleosols were formed under somewhat drier climate in comparison with the present time. However, the similarity of these paleosols and background surface soils in their morphological properties, reconstructed humus content, and averaged values of weathering indices Al₂O₃ ⋅ 100/(Al₂O₃ + CaO + MgO + Na₂O + K₂O) and Rb/Sr, as well as Mn/Sr, Mn/Al, and Mn/Fe indices characterizing the degree of biological activity attest to humidization of the paleoclimate during the period of construction of the kurgans. Among highly hazardous pollutants of the first toxicity class, the studied soils are enriched with As and Cd (in comparison with natural abundances of these elements in the lithosphere). In general, regional soils and parent material are enriched with As, Ni, Zn, Ba, and Sn, though the concentrations of these heavy metals in the soil profiles remain below the corresponding maximum permissible concentrations. The accumulation of toxic substances under the impact of anthropogenic pollution in the profiles of studied soils does not exceed the permissible values. The concentrations of heavy metals in the background surface soils are no higher than those in the medieval paleosols. The application of GIS technology demonstrated that 21 settlements and 130 necropolises of the Srostki community (second half of the 8th–12th centuries AD) were localized on fertile soils of leveled areas near large lakes and rivers (the Ob, Katun, Biya, Alei, and other rivers) and within wide valleys at the confluence of small streams with larger water bodies.

Broad-Scale Weather Patterns Encountered during Flight Influence Landbird Stopover Distributions

The dynamic weather conditions that migrating birds experience during flight likely influence where they stop to rest and refuel, particularly after navigating inhospitable terrain or large water bodies, but effects of weather on stopover patterns remain poorly studied. We examined the influence of broad-scale weather conditions encountered by nocturnally migrating Nearctic-Neotropical birds during northward flight over the Gulf of Mexico (GOM) on subsequent coastal stopover distributions. We categorized nightly weather patterns using historic maps and quantified region-wide densities of birds in stopover habitat with data collected by 10 weather surveillance radars from 2008 to 2015. We found spring weather patterns over the GOM were most often favorable for migrating birds, with winds assisting northward flight, and document regional stopover patterns in response to specific unfavorable weather conditions. For example, Midwest Continental High is characterized by strong northerly winds over the western GOM, resulting in high-density concentrations of migrants along the immediate coastlines of Texas and Louisiana. We show, for the first time, that broad-scale weather experienced during flight influences when and where birds stop to rest and refuel. Linking synoptic weather patterns encountered during flight with stopover distributions contributes to the emerging macro-ecological understanding of bird migration, which is critical to consider in systems undergoing rapid human-induced changes.

Мониторинг тяжелых металлов и мышьяка в донных отложениях водных объектов

The study of contamination of sediments of water bodies with chemical elements continues to be one of the important problems of geoecology. The lack of a formal normative base for these indicators has led to different and diverse approaches and methods to solve this problem. The selection of the territory of a large water body on the example of the Volga river basin is made. There are four different hierarchical levels of research objects. The questions of location in time and space of observation points for the change of pollution of the river sediments and reservoirs are considered and justified. Theoretical and methodical substantiation of sampling of these deposits, the allocation of silt fraction less than 0.020 mm, which allows to bring samples containing different size components to the «common denominator» in laboratory studies. The choice of geoaccumulation index as an indicator of the level of pollution of the studied objects is justified. It is recommended at the present stage to use the total index of toxic pollution to assess the total technogenic pressure on the studied area. The assessment of complex pollution of the sediments can also be carried out on the basis of the total toxic pollution. The necessity to use the same permanent set of seven heavy metals Cd, Hg, Pb, Zn, Cu, Cr, Ni and As in solving the problem is substantiated. To present the results of field and laboratory studies, along with traditional tables, diagrams and graphs, it is recommended to use a color scheme map, where the technogenic pressure is displayed from the blue to the green and yellow to the red – the most dangerous. To assess the quality of the sediments for areas of water bodies experiencing anthropogenic load from the 1st – 2nd city-forming enterprises, can be carried out on the mono-element schematic maps or diagrams.

Artificial Light at Night is Related to Broad-Scale Stopover Distributions of Nocturnally Migrating Landbirds along the Yucatan Peninsula, Mexico

The distributions of birds during migratory stopovers are influenced by a hierarchy of factors. For example, in temperate regions, migrants are concentrated near areas of bright artificial light at night (ALAN) and also the coastlines of large water bodies at broad spatial scales. However, less is known about what drives broad-scale stopover distributions in the tropics. We quantified seasonal densities of nocturnally migrating landbirds during spring and fall of 2011–2015, using two weather radars on the Yucatan peninsula, Mexico (Sabancuy and Cancun). We tested the influence of environmental predictors in explaining broad-scale bird stopover densities. We predicted higher densities in areas (1) closer to the coast in the fall and farther away in spring and (2) closer to bright ALAN and with lower ALAN intensity in both seasons. We found that birds were more concentrated near the coastline in the fall and away from it in spring around Cancun but not Sabancuy. Counter to our expectations, we detected increased bird densities with increased distance from lights in spring around Sabancuy, and in both seasons around Cancun, suggesting avoidance of bright areas during those seasons. This is the first evidence of broad-scale bird avoidance of bright areas during stopover.

Tracking pollution and its sources in the catchment‐lake system of major waterbodies in Kazakhstan

AbstractThe objective of the present study was to identify the sources and routes of entry of heavy metals and nutrients into several large waterbodies in the arid zone of Kazakhstan, namely Lake Balkhash and Samarkan and Shardara reservoirs. A data visualization method was used for this purpose. Statistical mapping, based on referencing coordinates of the material selection points, was performed with the Statistics 12.0 program. Matching statistical maps with the waterbody contours was performed in Adobe Photoshop. Maps of the spatial distribution of heavy metals (cadmium, nickel, cobalt, lead, zinc and copper) and nutrients were constructed for all three study waterbodies. Data visualization clearly illustrated the relationship between the distribution of pollutants in the study waterbodies, as well as the sources of anthropogenic pollution. Based on the mapping exercise, it was established that Cu and Zn entered the waterbodies mainly in agricultural waste waters, while Cd, Ni, Co, Pb and partly Zn entered the waterbodies mainly in industrial and surface run‐off. Nutrients enter the waterbodies mainly in river and municipal waters. The constructed maps demonstrate the role of the constant flow in the distribution of pollutants in the waters of Lake Balkhash. The results also indicate that statistical mapping is an effective tool for identifying the sources and routes of pollutant entry into waterbodies. The imposition of statistical maps on the contours of waterbodies of concern provides a mapping method allowing for more visually compelling data and information for a wide circle of users and managers.

Spatially coherent clusters of summer precipitation extremes in the Tibetan Plateau: Where is the moisture from?

Abstract Atmospheric moisture dynamics for extreme precipitation is poorly understood in the “Asian water towers”. Using a new spatial clustering approach for extreme events, the Tibetan Plateau (TP) is divided into coherent sub-areas, where the magnitude of Summer Precipitation Extremes (SPEs) decreases from southeast to northwest in the past decades. There are two dominant pathways of external moisture convergences: one from the south, the other from the west, which are regulated by Indian monsoon and Westerlies, respectively. As Yarlung Zangbo Ground Canyon provides a natural passage for water vapor transport, SPEs in the southeast clusters absorb with around 75% of total moisture from the Bay of Bangla. The onset of SPEs in the southeast is also found earlier than the other clusters across the TP. Local recycling is another important moisture source for SPEs in areas with large water bodies. Moreover, teleconnections are initially examined between large-scale climate signals and moisture trajectories under the extreme events, demonstrating the potential influence of atmospheric circulations on SPEs in the TP.

Самые крупные озера Курильских островов: морфометрия и географическое распределение (материалы к базе данных)

The work presents modern data on the location, morphometry, and genesis of the largest lakes basins of the Kuril Islands obtained in the volcanological expeditions of the IMGG FEB RAS during 2005– 2018 and using open geographic information resources. 1099 lakes were sampled according to the criterion S ≥ 1 km², the list of studied objects included 20 reservoirs, represented by 7 volcanic and 13 lagoon lakes. The considered lakes are clearly divided according to their origin, area and height of the mirror, and maximum depth. The most part of large lakes falls on the Southern Kurils, and the largest water body – the volcanic lake Koltsevoe – is located on Onekotan Island, which is a part of the group of the Northern Kurils. Volcanic lakes occupy an area of 48.26 km² (60 % of the total area of 20 lakes), the depth varies in the range from several tens to several hundred meters. This category of lakes is characterized by relatively high levels of the mirror, which range from 50 to 648 m above sea level. Lagoon lakes occupy an area of 32.15 km² (40 % of the total area of 20 lakes), the depth of water bodies is small – from 1 to 23 m, the absolute height of the lake mirror is from 1–5 to 8–9 m.

The Gulf of Mexico: A Maritime History by John S. Sledge

Reviewed by: The Gulf of Mexico: A Maritime History by John S. Sledge Gene Allen Smith and Nancy Baker Jones The Gulf of Mexico: A Maritime History. By John S. Sledge. (Columbia: University of South Carolina Press, 2019. Pp. 280. Illustrations, notes, bibliography, index.) The Gulf of Mexico, the earth’s tenth largest body of water, laps the coast of the southern United States and connects it to Central and South America. As such, the Gulf represents an important nexus where people, empires, and trade intersect to define modern geopolitical boundaries. John Sledge’s maritime history of the Gulf provides us with a broad survey of the Gulf’s importance to human history. By exploring how people, ships, and cities have interacted and developed, he has offered a well-written and riveting history that foretells the continuing importance of the Gulf of Mexico. Beginning with the Gulf’s pre-history, Sledge details the rich Native American, Spanish, French, English, American, and Confederate stories that comprise the fabric of this region. Situated at the western end of the Gulf with a coast that stretches 367 miles, Texas joins the story during Sledge’s explanation of the coastal landscape at the time of LaSalle’s 1684–86 expedition, the Mexican and Texas independence movements, and the Confederate and modern periods. Beginning in January 1836, the first Texas Navy—initially consisting of four schooners and privateers—plied Gulf waters, helping to maintain Texas’s independence and even supporting Yucatan’s independence movement. By 1839, four schooners, two brigs, and a sloop constituted a new Texas Navy, and this fleet patrolled sea lanes along the Texas coast, keeping ports open until the Republic joined the United States in 1846. Galveston Island became Texas’s connection to the world. Named after eighteenth-century Spanish military leader Bernardo de Gálvez y Madrid, the island served as the headquarters for Jean Lafitte’s piratical operations and for Louis-Michel Aury’s privateering empire during the early nineteenth century. In January 1863 Confederate General John B. Magruder expelled Union forces from the island, and Galveston remained the only major port in Confederate hands at the end of the war. Later in the nineteenth century, the city emerged as one of the largest commercial ports in the United States. Yet the great Galveston hurricane of 1900, which still ranks as the deadliest U.S. natural disaster, devastated [End Page 81] the “Queen City of the Gulf,” and the city never regained its national importance. Thereafter, the development of the Houston Ship Channel brought the port of Houston into competition with and eventually eclipsed Galveston as the natural port for sea commerce. By the late twentieth century, Galveston reemerged as a financial and tourist destination and even weathered Hurricane Ike in 2008, which did considerable damage to buildings along the seawall. During the twentieth century the Gulf became a center for the petroleum industry, with oil platforms marking the water’s horizon. Pipelines crisscrossed the underwater surface of the Gulf while oil tankers floated above. Petroleum became the source of wealth that propelled the development of the western Gulf states; yet, the explosion of the tanker Mega Borg off Galveston in June 1990 and the Deepwater Horizon disaster in April 2010 revealed ongoing tensions between oil production and tourist-centric development. During the spring of 2017, President Donald J. Trump rolled back decades-long restrictions on drilling in the Gulf, signaling a significant change that caused some to ask, “What is the future for the American Sea?” This maritime history of the Gulf fills an important need. The first book to undertake this ambitious topic, The Gulf of Mexico sails into new territory. Sledge embraces a topic that is voluminous and offers a readable work supported by sound research. This is not the last word to be said about the Gulf, but it will serve as a launching pad for future scholars. Gene Allen Smith Texas Christian University Copyright © 2020 The Texas State Historical Association