Angel Ruiz-Angulo

University of Iceland | HI · Institute of Earth Sciences

Plain Language Summary In the Gulf of Mexico (GoM), anticyclonic eddies, known as Loop Current rings (LCRs) carrying warm and salty water shape the basin's water mass properties, which in turn, affects the regional climate and marine life. The water mass properties are altered by turbulent mixing. However, the mechanisms leading to the mixing of Go...

We report tele-seismic waves detection from multiple earthquakes on an operational subsea cable from Iceland to Ireland. Using per-span laser interferometry with 100km spacing, we report clear detection of S-, P- and surface waves from multiple world-wide earthquakes, enabling seismic analysis for early warning applications.

Tidewater glaciers are highly vulnerable to climate change due to warming from both atmospheric and seawater sources. Most tidewater glaciers are rapidly retreating, but little is known about how glacial melting modifies coastal biogeochemical cycles. Here, we investigate carbonate and nutrient dynamics and fluxes in an expanding proglacial tidal l...

We present a kinematic slip model and a simulation of the ensuing tsunami for the 2020 Mw 7.0 Néon Karlovásion (Samos, Eastern Aegean Sea) earthquake, generated from a joint inversion of high-rate GNSS, strong ground motion and InSAR data. From the inversion, we find that the source time function has a total duration of ∼20 s with three peaks at ∼4...

The northeastern part of the North Atlantic subpolar gyre is a key passage for the Atlantic Meridional Overturning Circulation upper cell. To this day, the precise pathway and intensity of bottom currents in this area is not clear. In this study, we make use of regional high resolution numerical modeling to suggest that the main bottom current flow...

NO2 outflow fluxes were calculated from the City of Toluca, Mexico during January-February 2017 using a mobile zenith viewing mini-DOAS instrument. Measurements were performed in a cross-section of the outflow plume from the Toluca Valley Metropolitan Area with an instrument operating in the visible wavelength region (356 to 510 nm). NO2 retrievals...

The northeastern part of the North Atlantic subpolar gyre is a key passage for the Atlantic Meridional Overturning Circulation upper cell. To this day, the precise pathway and intensity of bottom currents in this area have not reached a consensus. In this study, we make use of regional high resolution numerical modeling to suggest that the main bot...

The Bay of Campeche, located in the southern Gulf of Mexico (GoM), is characterized by a semi-permanent cyclonic circulation commonly referred to as the Campeche Gyre (CG). Several studies documenting its upper layer structure have suggested a possible relationship between its seasonal variability and the wind stress, and that non-seasonal variabil...

The Bay of Campeche in the southern Gulf of Mexico (GoM) is characterized by a semi-permanent cyclonic circulation commonly referred to as the Campeche Gyre (CG). Several studies, documenting its upper layer structure, have suggested a relationship between its seasonal occurrence and the wind, and have proposed that non-seasonal variability arises...

On January 15, 2022 the Hunga Tonga Hunga Ha’apai volcano erupted violently, generating a significant tsunami that was observed around the world. This is the first volcanic tsunami that has been observed worldwide by the modern deep- and shallow-water hydrodynamic instrument network. Here we study deep water DART buoy and coastal tide gauges record...

Ostracods have been used in coastal monitoring as indicators of recent and past environmental changes due to their relatively high diversity, abundance and sensitivity. To assess the influence of salinity and potential human impacts on their diversity and distribution in two neighbouring bays in a growing urban area in SW Iceland, a set of 28 surfa...

The Atmospheric Boundary Layer (ABL) height is a key parameter in air quality research as well as for numerical simulations and forecasts. The identification of thermally stable layers, often with radiosondes, has been a common approach for estimating ABL height, though with limited temporal coverage. Remote sensing techniques offer essentially con...

We present a slip model for the 2021 M 7 Acapulco, Mexico, earthquake produced by inversion of strong motion, Global Navigation Satellite Systems, tide gauge, and Interferometric Synthetic Aperture Radar data. The earthquake occurs within the Guerrero gap, identified as a region of concern for its seismogenic potential and paucity of large events....

Experimental lock-release gravity currents are investigated as they propagate downslope over a synthetic varying topography. We emulate and investigate the dynamics of thermally driven winds that propagate downslope while interacting with the roughness of a topographic surface. The mixing processes between the gravity currents and their surrounding...

Here we show a slip model for the 2021 M7 Acapulco, Mexico, earthquake produced by inversion of strong motion, GNSS, tide gauge, and InSAR data. The earthquake occurs within the Guerrero gap, identified as a region of concern for its seismogenic potential and paucity of large events. We find that rupture was compact, constrained to depths between 1...

The Atmospheric Boundary Layer (ABL) height is a key parameter in air quality research as well as in order to parametrize numerical simulations and forecasts. The identification of thermally stable layers has been one of the most common approaches in order to estimate this height. However, radiosonde's coarse temporal resolution is not enough to in...

This work presents new evidence for conducive conditions for the existence of overturning instabilities in the mixed layer across a mesoscale anticyclonic Loop Current Eddy (LCE) and surrounding cyclonic eddies in the Gulf of Mexico (GoM). The LCE was intensively sampled using four gliders during 12 months. The LCE is characterized by a strong anom...

Lower tropospheric thermal structure greatly affects atmospheric boundary-layer (ABL) stability and mixing processes with the free troposphere. In particular, in polluted urban zones, ABL stratification becomes a key variable in air quality research. This study focuses on generating a climatology (1990-2017) of the seasonal variability of ABL therm...

Turbulent mixing on continental shelves plays roles in the structure and dynamics of marine ecosystems, nutrient cycling, primary production and dispersion of pollutants. Describing and understanding internal wave dynamics enables improved mapping of mixing over continental shelves, especially in complex environments where many processes may intera...

This study investigates the vertical structure of the dynamical properties of a warm-core ring in the Gulf of Mexico (Loop Current ring) using glider observations. We introduce a new method to correct the glider’s along-track coordinate, which is, in general, biased by the unsteady relative movements of the glider and the eddy, yielding large error...

This study investigates the vertical structure of the dynamical properties of a warm-core ring in the Gulf of Mexico (Loop Current ring) using glider observations. We introduce a new method to correct the glider’s along-track coordinate which is, in general, biased by the unsteady relative movements of the glider and the eddy, yielding large errors...

Ongoing ocean warming can release methane (CH4) currently stored in ocean sediments as free gas and gas hydrates. Once dissolved in ocean waters, this CH4 can be oxidized to carbon dioxide (CO2). While it has been hypothesized that the CO2 produced from aerobic CH4 oxidation could enhance ocean acidification, a previous study conducted in Hudson Ca...

The effects of stratification and Yucatan Current (YC) transport on the dynamics of the Loop Current (LC) and Loop Current Eddies (LCEs) are studied using a primitive equation, 2½ nonhomogeneous layered model, which reproduces the main dynamical features of the upper ocean circulation in the Gulf of Mexico (GoM). The analysis considers the observed...

The La Crucecita earthquake ruptured on the megathrust, generating strong shaking and a modest but long-lived tsunami. This is a significant earthquake that illuminates important aspects of the behavior of the megathrust as well as the potential related hazards. The rupture is contained within 15–30 km depth, ground motions are elevated, and the en...

The La Crucecita earthquake ruptured on the megathrust generating strong shaking and a modest, long-lived tsunami. This is a significant earthquake that illuminates important aspects of the behavior of the megathrust as well as the potential related hazards. The rupture is contained within 15-30km depth, ground motions are elevated and the energy t...

Relatively minor amounts of methane, a potent greenhouse gas, are currently emitted from the oceans to the atmosphere, but such methane emissions have been hypothesized to increase as oceans warm. Here, we investigate the source, distribution, and fate of methane released from the upper continental slope of the U.S. Mid‐Atlantic Bight, where hundre...

In this study, we harness the 25-year satellite-altimeter record, in concert with a vast array of in situ measurements, to estimate the heat content anomaly of 32 warm-core rings in the Gulf of Mexico (GoM). The decay rate of these mesoscale eddies is studied in detail, and it is shown that they release the majority of their heat as they drift in t...

A long term characterization of the nocturnal Atmospheric Boundary Layer (ABL) over Mexico City is made in terms of radiosonde data. The more stable conditions are found during the dry months and they are coincident with the worst air quality. On the other hand, the diurnal evolution of the Atmospheric Boundary Layer is studied by processing lidar...

Mexico City constitutes one of the largest concentrations of population on the planet and is settled in a valley that, before the 16th century, had a lake system. The lakes were desiccated artificially, and currently, only small lakes remain. The impact of the lake system desiccation on precipitation was studied by performing numerical experiments:...

In recent years, many tsunamis have surprised the scientific community with several unfortunate examples, which have led to changes in both forecast and prevention implementations. Among key problems are underestimations of the size and inaccurate timing of pending tsunamis. For example, the tsunami generated by the magnitude 9.0 Tohoku (Japan) ear...

Recent glider observations in the Gulf of Mexico revealed the fine-vertical scale thermohaline structure of a Loop Current Eddy (LCE). Partially compensating temperature and salinity anomalies are shown to organize as thin layers below the eddy and at its periphery. They have vertical scales ranging from 2 to 60 m and have a large lateral coherence...

This article presents experimental measurements involving immersed collisions between a rigid impactor and a deformable target for a wide range of Reynolds and Stokes numbers. Three aluminium alloys are used as solid targets submerged in seven different fluids covering a wide range of viscosity and density. The collision and rebound velocities as w...

Controlled particle-wall collisions are conducted in various fluids. Impact and rebound velocities of a particle as well as the diameter and depth of the generated crater on the surface are reported in this dataset. Three materials are used for the walls: aluminum alloys 6061, 2014, and 7075. The impact experiments are performed in seven fluids wit...

Subduction zones, where two tectonic plates converge, are generally dominated by large thrust earthquakes. Nonetheless, normal faulting from extensional stresses can occur as well. Rare large events of this kind in the instrumental record have typically nucleated in and ruptured the top half of old and cold lithosphere that is in a state of extensi...

The 8 September 2017 M8.2 Tehuantepec, Mexico, earthquake ruptured an ~150-km-long high-angle normal fault below the subduction zone megathrust. A tsunami was generated by the event with surveyed runup as large as 3 m. Tide gauges in the region show a remarkably long duration of the tsunami with oscillations within the very wide and shallow Tehuant...

The behavior of slip close to the trench during earthquakes is not well understood, and observations of large earthquakes breaking the near trench fault surface are rare. The 1995 Mw 8.0 Jalisco earthquake seems to have broken the near-trench area, as evidenced by large Ms-Mw disparity, small high-frequency radiated energy compared to total energy,...

The vertical structure of a recently detached Loop Current Eddy (LCE) is studied using in situ data collected with an underwater glider from August to November 2016. Altimetry and Argo data are analyzed to discuss the context of the eddy shedding and evolution as well as the origin and transformation of its thermohaline properties. The LCE appeared...

This study describes in detail the water masses of the Gulf of Mexico (GoM) west of 88 based on their thermohaline properties and dissolved oxygen concentration. The existent historical information is complemented with new data from 14 cruises, Argo floats and over one year of continuous glider monitoring. The results describe the general hydrograp...

The diurnal and seasonal variability of the mixed-layer height in urban areas has implications for ground-level air pollution and the meteorological conditions. Measurements of the backscatter of light pulses with a commercial lidar system were performed for a continuous period of almost six years between 2011 and 2016 in the southern part of Mexic...

High-resolution hydrographic measurements reveal the presence of three intrathermocline eddies (ITEs) embedded within a loop current eddy. ITEs are lenticular bodies of nearly homogeneous water, which contrasts with the well-stratified surrounding water. Their radii and thickness ranged between 19–32 km and 150–250 m. Negative relative vorticity wi...

On September 8, 2017 (UTC), a normal-fault earthquake occurred 87 km off the southeast coast of Mexico. This earthquake generated a tsunami that was recorded at coastal tide gauge and offshore buoy stations. First, we conducted a numerical tsunami simulation using a single-fault model to understand the tsunami characteristics near the rupture area,...

The 8 September 2017, Mw 8.2 earthquake offshore Chiapas, Mexico, is the largest earthquake in recorded history in Chiapas since 1902. It caused damage in the states of Oaxaca, Chiapas and Tabasco, including more than 100 fatalities, over 1.5 million people were affected, and 41,000 homes were damaged in the state of Chiapas alone. This earthquake,...

This study develops a novel computational framework to carry out probabilistic tsunami hazard assessment for the Pacific coast of Mexico. The new approach enables the consideration of stochastic tsunami source scenarios having variable fault geometry and heterogeneous slip that are constrained by an extensive database of rupture models for historic...

Wind related research, carried out in the Laboratorio de Ingeniería y Procesos Costeros del Instituto de Ingeniería de la UNAM (LIPC) at Sisal, Yucatán is revisited. Some experimental results, obtained with a 50 m meteorological mast equipped with sonic anemometers (between 2010 and 2016) are discussed, along with some unpublished results and LIDAR...

Abstract This study presents the observation of large amplitude internal wave activity, in the order of 50 m, near the head of the Petacalco submarine canyon located in the Mexican Pacific. The waves propagate with periods similar to the M2 tide component and the observations show that temperature rates of change reached up to 10 C / hr. The presen...

The dynamics of a single air bubble rising through a stably-stratified sharp interface, separating two Newtonian miscible liquids, are studied experimentally. Both liquids were water-glycerin mixtures; salt was added to the lower fluid to make its density higher than the upper one. The size of the bubbles was varied to span a range of terminal velo...

Oceanic internal waves are closely linked to turbulence. Here, a relationship between vertical wavenumber (kz) spectra of finescale vertical kinetic energy (VKE) and turbulent dissipation ε is presented using more than 250 joint profiles from five diverse dynamic regimes, spanning latitudes between the equator and 60°. In the majority of the spectr...

This manuscript presents a numerical study of the thermal response for the months of January-February and August-September in a scenario that includes a water body representing the lake system of the Basin of Mexico excluding the urban coverage. The numerical experiment aims to replicate the set of lakes that formed the lacustrine system 500 years...

This manuscript is intended to review some of the methods used to estimate one of the most useful parameters in Ocean Modeling: the diapycnal diffusivity. Specifically it focus on simultaneous measurements carried out at two different locations in the deep ocean. The techniques reviewed here to estimate diapycnal mixing in the ocean interior are: t...

This manuscript presents a numerical study of the thermal response for the months of January-February and August-September in a scenario that includes a water body representing the lake system of the Basin of Mexico excluding the urban coverage. The numerical experiment aims to replicate the set of lakes that formed the lacustrine system 500 years...

We report on the results of a combined experimental and numerical study on the fluid motion generated by the controlled approach and arrest of a solid sphere moving towards a solid wall at moderate Reynolds number. The experiments are performed in a small tank filled with water for a range of Reynolds numbers for which the flow remains axisymmetric...

This paper presents the approach and rebound of a particle colliding with a deformable surface in a viscous liquid. The complex interaction between the fluid and the solid phases is coupled through the dynamics of the flow as well as the deformation process. For the experiments, steel particles impacted ductile aluminum alloys samples immersed in a...

Multiphase flows are fairly complex and they are usually studied as a bulk. In this thesis, these flows are approached by looking at single particle interactions (particle-particle and particle-wall). This work presents experimental measurements of the approach and rebound of a particle colliding with a ``deformable' surface in a viscous liquid. Th...

This reply addresses three main issues raised in the comment of Andreotti et al. [2008]. First, the turning of ray paths in a granular material does not preclude the propagation of body waves and the resonance condition described by Vriend et al. [2007]. The waveguide model still holds in the dune for the observed velocities, even with a velocity i...

Desert booming can be heard after a natural slumping event or during a sand avalanche generated by humans sliding down the slip face of a large dune. The sound is remarkable because it is composed of one dominant audible frequency (70 to 105 Hz) plus several higher harmonics. This study challenges earlier reports that the dunes' frequency is a func...

For dry systems (gas-particle) prior studies have investigated the effects of inelasticity on particle rebound and deformation. In wet systems (liquid-particle) the viscous forces can complicate the collision process. For elastic conditions, a range of particle Stokes number where lubrication forces are non-negligible has been previously found. The...