Towards an end-to-end analysis and prediction system for weather, climate, and marine applications in the Red Sea

Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 102(1), (2021): E99-E122, https://doi.org/10.1175/BAMS-D-19-0005.1.The Red Sea, home to the second-longest coral reef system in the world, is a vital resource for the Kingdom of Saudi Arabia. The Red Sea provides 90% of the Kingdom’s potable water by desalinization, supporting tourism, shipping, aquaculture, and fishing industries, which together contribute about 10%–20% of the country’s GDP. All these activities, and those elsewhere in the Red Sea region, critically depend on oceanic and atmospheric conditions. At a time of mega-development projects along the Red Sea coast, and global warming, authorities are working on optimizing the harnessing of environmental resources, including renewable energy and rainwater harvesting. All these require high-resolution weather and climate information. Toward this end, we have undertaken a multipronged research and development activity in which we are developing an integrated data-driven regional coupled modeling system. The telescopically nested components include 5-km- to 600-m-resolution atmospheric models to address weather and climate challenges, 4-km- to 50-m-resolution ocean models with regional and coastal configurations to simulate and predict the general and mesoscale circulation, 4-km- to 100-m-resolution ecosystem models to simulate the biogeochemistry, and 1-km- to 50-m-resolution wave models. In addition, a complementary probabilistic transport modeling system predicts dispersion of contaminant plumes, oil spill, and marine ecosystem connectivity. Advanced ensemble data assimilation capabilities have also been implemented for accurate forecasting. Resulting achievements include significant advancement in our understanding of the regional circulation and its connection to the global climate, development, and validation of long-term Red Sea regional atmospheric–oceanic–wave reanalyses and forecasting capacities. These products are being extensively used by academia, government, and industry in various weather and marine studies and operations, environmental policies, renewable energy applications, impact assessment, flood forecasting, and more.The development of the Red Sea modeling system is being supported by the Virtual Red Sea Initiative and the Competitive Research Grants (CRG) program from the Office of Sponsored Research at KAUST, Saudi Aramco Company through the Saudi ARAMCO Marine Environmental Center at KAUST, and by funds from KAEC, NEOM, and RSP through Beacon Development Company at KAUST

Resonantly forced gravity–capillary lumps on deep water. Part 1. Experiments

The wave pattern generated by a pressure source moving over the free surface of deep water at speeds, U, below the minimum phase speed for linear gravity–capillary waves, cmin, was investigated experimentally using a combination of photographic measurement techniques. In similar experiments, using a single pressure amplitude, Diorio et al. (Phys. Rev. Lett., vol. 103, 2009, 214502) pointed out that the resulting surface response pattern exhibits remarkable nonlinear features as U approaches cmin, and three distinct response states were identified. Here, we present a set of measurements for four surface-pressure amplitudes and provide a detailed quantitative examination of the various behaviours. At low speeds, the pattern resembles the stationary state (U = 0), essentially a circular dimple located directly under the pressure source (called a state I response). At a critical speed, but still below cmin, there is an abrupt transition to a wave-like state (state II) that features a marked increase in the response amplitude and the formation of a localized solitary depression downstream of the pressure source. This solitary depression is steady, elongated in the cross-stream relative to the streamwise direction, and resembles freely propagating gravity–capillary ‘lump’ solutions of potential flow theory on deep water. Detailed measurements of the shape of this depression are presented and compared with computed lump profiles from the literature. The amplitude of the solitary depression decreases with increasing U (another known feature of lumps) and is independent of the surface pressure magnitude. The speed at which the transition from states I to II occurs decreases with increasing surface pressure. For speeds very close to the transition point, time-dependent oscillations are observed and their dependence on speed and pressure magnitude are reported. As the speed approaches cmin, a second transition is observed. Here, the steady solitary depression gives way to an unsteady state (state III), characterized by periodic shedding of lump-like disturbances from the tails of a V-shaped pattern.National Science Foundation (U.S.) (NSF grant DMS-0604416)National Science Foundation (U.S.) (NSF grant DMS-098122)National Science Foundation (U.S.) (NSF grant OCE-751853)United States. Air Force Office of Scientific Research (AFSOR (grant FA9550-07-0005))ARCS Foundatio

Resonantly forced gravity–capillary lumps on deep water. Part 2. Theoretical model

A theoretical model is presented for the generation of waves by a localized pressure distribution moving on the surface of deep water with speed near the minimum gravity–capillary phase speed, c[subscript min]. The model employs a simple forced–damped nonlinear dispersive equation. Even though it is not formally derived from the full governing equations, the proposed model equation combines the main effects controlling the response and captures the salient features of the experimental results reported in Diorio et al. (J. Fluid Mech., vol. 672, 2011, pp. 268–287 – Part 1 of this work). Specifically, as the speed of the pressure disturbance is increased towards c[subscript min], three distinct responses arise: state I is confined beneath the applied pressure and corresponds to the linear subcritical steady solution; state II is steady, too, but features a steep gravity–capillary lump downstream of the pressure source; and state III is time-periodic, involving continuous shedding of lumps downstream. The transitions from states I to II and from states II to III, observed experimentally, are associated with certain limit points in the steady-state response diagram computed via numerical continuation. Moreover, within the speed range that state II is reached, the maximum response amplitude turns out to be virtually independent of the strength of the pressure disturbance, in agreement with the experiment. The proposed model equation, while ad hoc, brings out the delicate interplay between dispersive, nonlinear and viscous effects that takes place near c[subscript min], and may also prove useful in other physical settings where a phase-speed minimum at non-zero wavenumber occurs.ARCS FoundationNational Science Foundation (U.S.) (NSF grant DMS-0604416)National Science Foundation (U.S.) (NSF grant DMS-098122)National Science Foundation (U.S.) (NSF grant OCE-751853)United States. Air Force Office of Scientific Research (AFSOR (grant FA9550-07-0005)

Invasion Patterns of the Coypu, Myocastor coypus, in Western Central Greece: New Records Reveal Expanding Range, Emerging Hotspots, and Habitat Preferences

The coypu (Myocastor coypus), a semi-aquatic rodent native to South America, has established invasive populations across North America, Asia, and Europe. In Greece, since its initial recording in 1965, the species has been rapidly expanding, forming sizable populations in northern continental regions. However, the extent of its invasion and the environmental drivers shaping its distribution and spatial patterns in western–central Greece remain poorly understood. Here, we address this knowledge gap, aiming to identify and map new coypu records, investigate the relationship between coypu presence and habitat characteristics, and analyze its spatial distribution. Between 2020 and 2023, we conducted 50 field surveys across the study area, documenting direct and indirect evidence of coypu presence. We integrated kernel density estimation, Getis-Ord Gi*, and Anselin local Moran’s I to identify spatial distribution patterns and hotspots of the coypu. Additionally, we analyzed environmental factors including land cover type, total productivity, and geomorphological features to determine their influence on habitat selection. Our findings reveal significant spatial clustering of coypus, with 12 identified hotspots primarily located in protected areas, and highlight tree cover density and productivity variability as key predictors of coypu presence. The suitability of western–central Greece for the coypu appears to be driven by extensive wetlands and interconnected hydrological systems, with hotspots concentrated in lowland agricultural landscapes, providing essential data to guide targeted management strategies for mitigating the ecological risks posed by this invasive species. © 2025 by the authors

Invasion Patterns of the Coypu, <i>Myocastor coypus</i>, in Western Central Greece: New Records Reveal Expanding Range, Emerging Hotspots, and Habitat Preferences

The coypu (Myocastor coypus), a semi-aquatic rodent native to South America, has established invasive populations across North America, Asia, and Europe. In Greece, since its initial recording in 1965, the species has been rapidly expanding, forming sizable populations in northern continental regions. However, the extent of its invasion and the environmental drivers shaping its distribution and spatial patterns in western–central Greece remain poorly understood. Here, we address this knowledge gap, aiming to identify and map new coypu records, investigate the relationship between coypu presence and habitat characteristics, and analyze its spatial distribution. Between 2020 and 2023, we conducted 50 field surveys across the study area, documenting direct and indirect evidence of coypu presence. We integrated kernel density estimation, Getis-Ord Gi*, and Anselin local Moran’s I to identify spatial distribution patterns and hotspots of the coypu. Additionally, we analyzed environmental factors including land cover type, total productivity, and geomorphological features to determine their influence on habitat selection. Our findings reveal significant spatial clustering of coypus, with 12 identified hotspots primarily located in protected areas, and highlight tree cover density and productivity variability as key predictors of coypu presence. The suitability of western–central Greece for the coypu appears to be driven by extensive wetlands and interconnected hydrological systems, with hotspots concentrated in lowland agricultural landscapes, providing essential data to guide targeted management strategies for mitigating the ecological risks posed by this invasive species