Robert Monjo

Complutense University of Madrid | UCM · Departamento de Geometría y Topología

Meteorological droughts will become the principal factor driving compound hot-dry events and analysis thereof is therefore fundamental with regard to understanding future climate patterns. The average citizen knows little of geometry, but it plays an essential role in the characteristics of the droughts, by means of “fractional lengths”. We analyze...

The gauge formalism in telepalallel gravity provides an interesting viewpoint to describe interactions according to an anholonomic observer’s tetrad basis. Without going into assessing the complete viability of quantization in an early stage, this paper explores classical gravity within the framework of a classical-to-quantum bridge between the SU(...

Modified Newtonian dynamics (MOND) and similar proposals can (at least partially) explain the excess rotation of galaxies or the equivalent mass-discrepancy acceleration, without (or by reducing) the requirement of dark matter halos. This paper develops a modified gravity model to obtain a local limit to general relativity (GR) compatible with a co...

Despite the success of dark-matter models, unresolved issues require exploring alternatives such as modified gravity theories. In this context, we examine the compatibility of the Hyperconical Modified Gravity (HMG) with galaxy rotation curves inferred from weak-lensing data. The research addresses the existing limitations of Modified Newtonian Dyn...

Modified Newtonian Dynamics (MOND) was originally proposed to model galaxy rotation curves without dark matter. However, MOND presents difficulties in explaining the Radial Acceleration Relation (RAR) observed in galaxy clusters, and moreover, it does not completely eliminate the need for dark matter, since it requires using sterile neutrinos to ex...

Modern cosmology presents important challenges such as the \textit{Hubble tension}, \textit{El Gordo's collision} or the \textit{impossible galaxies} ($z > 10$). Slight modifications to the standard model propose new parameters (e.g. the early and dynamical dark energy). On the other hand, alternatives such as the coasting universes (e.g. the \text...

Modern cosmology presents important challenges such as the Hubble Tension, El Gordo’s collision, or the impossible galaxies ( z > 10). Slight modifications to the standard model propose new parameters (e.g., the early and dynamical dark energy). On the other hand, alternatives such as the coasting universes (e.g., the hyperconical model and the spa...

General relativity (GR) is the most successful theory of gravity, with great observational support at local scales. However, to keep GR valid at over cosmic scales, some phenomena (such as the flat galaxy rotation curves and the cosmic acceleration) require the assumption of exotic dark matter. The radial acceleration relation (RAR) indicates a tig...

It is widely known from energy balances that global oceans play a fundamental role in atmospheric seasonal anomalies via coupling mechanisms. However, numerical weather prediction models still have limitations in long-term forecasting due to their nonlinear sensitivity to initial deep oceanic conditions. As the Mediterranean climate has highly unpr...

Climate change impacts are accelerating and intensifying, as observed over the past years, especially in the past year 2023.The current CMIP6 global climate simulations (GCMs) show higher climate sensitivity resulting in stronger warming and related impacts than previous simulations. Mountain regions are especially vulnerable as the warming climate...

The atmosphere is a highly non-linear dynamic system, where equations can present some solutions known as strange attractors since they have non-integer dimensions, or in other words, fractional volumes. The fractality in meteorology and climatology is reflected in the self-similarity at different spatial and temporal scales. For instance, atmosphe...

Rainfall, or more generally the precipitation process (flux), is a clear example of chaotic variables resulting from a highly nonlinear dynamical system, the atmosphere, which is represented by a set of physical equations such as the Navier–Stokes equations, energy balances, and the hydrological cycle, among others. As a generalization of the Eucli...

Rainfall, or more generally the precipitation process (flux), is a clear example of chaotic variables resulting from a highly nonlinear dynamical system, the atmosphere, represented by a set of physical equations such as the Navier-Stokes equations, energy balances and hydrological cycle among others. As a generalization of the Euclidean (ordinary)...

Modified Newtonian dynamics (MOND) and similar proposals can (at least partially) explain the excess rotation of galaxies or the equivalent mass-discrepancy acceleration, without (or by reducing) the requirement of dark matter halos. This paper develops a modified gravity model to obtain local limit to the general relativity (GR) compatible with a...

The Universe expansion rate has two different but very precise values ( 67.4 ± 0.5 and 73.30 ± 1.04 km s⁻¹Mpc⁻¹) that are not compatible. This problem, known as a Hubble tension, adds to other cosmological questions such as the origin of dark energy and the flatness problem. In turn, alternative models have attempted to explain similar phenomena bu...

Meteorological droughts will become the principal factor driving compound hot-dry events and analysis thereof is therefore fundamental with regard to understanding future climate patterns. The average citizen knows little of geometry, but it plays an essential role in the characteristics of the droughts, by means of “fractional lengths”. We analyse...

Climate change effects on subdaily rainfall (from 5 min to a few hours) can hardly be measured in mid‐latitude climates due to the high natural variability of the precipitation patterns and their effects on local topography. The goal of this study was to obtain change projections of intensity–duration–frequency (IDF) curves, for up to 2‐h precipita...

Synergies among researches are supporting stakeholders and decision makers to reduce climate change impacts on the hydrological cycle thanks to climate services implemented in the Mediterranean area. For instance, CRISI-ADAPT-II project is monitoring adaptation planning through a real-time implementation and validation according to seasonal range f...

The Mediterranean region is a climate change hotspot, especially concerning issues of hydrological planning and urban water supply systems. In this context, the Jucar River Basin (Spain) presents an increase of frequency, intensity and duration of extreme meteorological phenomena, such as torrential rains, droughts or heat waves, which directly aff...

RESCCUE is an H2020 research project that aims to help cities around the world to become more resilient to physical, social, and economic challenges, using the water sector as the central point of the approach. Since 2016, RESCCUE has been developing methodologies and tools to support cities increase their resilience. The three RESCCUE cities, Barc...

The authors would like to make the following corrections about the published paper [...]

Presentation made during the UHINAK IV the Cross-border conference on climate and coastal change that took place in Irún (Spain) during the days 4-5 of November 2020. The abstract works on a comparative study between the ECCLIPSE and CRISI-ADAPT II European projects regarding their respective local future climate scenarios in the Port of Valencia....

Hyperconical universes can be represented by means of an inhomogeneous metric with positive curvature and linear expansion, that is isomorphic to flat universes with acceleration thanks to an appropriate transformation. Various symmetry properties of this metric are analysed, primarily at the local scale. In particular, the Lagrangian formalism and...

The results of recent climate projections for the city of Barcelona show a relevant increment of the maximum rainfall intensities for the period 2071-2100. Considering the city as a system of systems, urban resilience is strictly linked to the proper functioning of urban services and the knowledge of the cascading effects that may occur in the case...

p>En el marco del Proyecto europeo RESCCUE, las proyecciones climáticas para la ciudad de Barcelona muestran aumentos significativos de las intensidades máximas de precipitación para el horizonte del 2071-2100. En este trabajo se presenta la evaluación de la resiliencia de los servicios urbanos de la ciudad frente a episodios de inundación para con...

The measure of drought duration strongly depends on the definition considered. In meteorology, dryness is habitually measured by means of fixed thresholds (e.g. 0.1 or 1 mm usually define dry spells) or climatic mean values (as is the case of the standardised precipitation index), but this also depends on the aggregation time interval considered. H...

Dynamical climate models present an initialization problem due to the poor availability of deep oceanic data, which is required for the model assimilation process. In this sense, teleconnection indices, defined from spatial and temporal patterns of climatic variables, are conceived as useful tools to complement them. In this work, the near‐term cli...

Barcelona city has a strong dependence on the Ter and Llobregat reservoir system to provide drinking water. One main concern for the next century is a potential water scarcity triggered by a severe and persistent rainfall shortage. This is one of the climate-driven impacts studied within the EU funded project RESCCUE. To evaluate potential drought...

Drought duration strongly depends on the definition thereof. In meteorology, dryness is habitually measured by means of fixed thresholds (e.g. 0.1 or 1 mm usually define dry spells) or climatic mean values (as is the case of the Standard-ised Precipitation Index), but this also depends on the aggregation time interval considered. However, robust me...

The need for early seasonal forecasts stimulates continuous research in climate teleconnections. The large variability of the Mediterranean climate presents a greater difficulty in predicting climate anomalies. This article reviews teleconnection indices commonly used for the Mediterranean basin and explores possible extensions of one of them, the...

Heat- and cold-wave scenarios and temperature scenarios during the 21st century were obtained for Aragón (Spain), using, for the first time, nine Earth System Models (ESM) and two Representative Concentration Pathway (RCP) scenarios – RCP4.5 and RCP8.5 - belonging to the 5th Coupled Model Intercomparison Project (CMIP5). Local climate heat-wave sce...

The RESCCUE Project is an H2020 research project that aims to help cities around the world to become more resilient to physical, social, and economic challenges, using the water sector as the central point of the approach. RESCCUE will generate models and tools to bring this objective to practice, while delivering a framework enabling city resilien...

This letter explores the derivation of dark energy from a locally conformal projection of hyperconical universes. It focuses on the analysis of theoretical compatibility between the intrinsic view of the standard cosmology and an adequate transformation of hyperconical manifolds. Choosing some parametric family of locally conformal transformations...

This paper explores the derivation of dark energy from a locally conformal projection of hyperconical universes. It focuses on the analysis of theoretical compatibility between the intrinsic view of the standard cosmology and an adequate transformation of hyperconical manifolds. Choosing some parametric family of locally conformal transformations a...

A two-step statistical downscaling method has been reviewed and adapted to simulate twenty-first-century climate projections for the Gulf of Fonseca (Central America, Pacific Coast) using Coupled Model Intercomparison Project (CMIP5) climate models. The downscaling methodology is adjusted after looking for good predictor fields for this area (where...

Most of current cosmological theories are built combining an isotropic and homogeneous manifold with a scale factor that depends on time. If one supposes a hyperconical universe with linear expansion, an inhomogeneous metric can be obtained by an appropriate transformation that preserves the proper time. This model locally tends to a flat Friedman-...

Most of current cosmological theories are built combining an isotropic and homogeneous manifold with a scale factor that depends on time. If one supposes a hyperconical universe with linear expansion, an inhomogeneous metric can be obtained by an appropriate transformation that preserves the proper time. This model locally tends to a flat Friedman-...

Supplement containing the detailed results from the simulations: expected relative seasonal changes in daily absolute precipitation (mm/day) and daily mean temperature (ºC) throughout the XXI century per meteorological station and each of the climate change studied scenarios, predicted daily mean air temperature; predicted daily mean streamflow, an...

Climate changes affect aquatic ecosystems by altering temperatures and precipitation patterns, and the rear edges of the distributions of cold-water species are especially sensitive to these effects. The main goal of this study was to predict in detail how changes in air temperature and precipitation will affect streamflow, the thermal habitat of a...

Climate change affects aquatic ecosystems altering temperature and precipitation patterns, and the rear edge of the distribution of cold-water species is especially sensitive to them. The main goal was to predict in detail how change in air temperature and precipitation will affect streamflow, the thermal habitat of a cold-water fish (brown trout,...

For the purposes of weather nowcasting, flood risk monitoring and water resources assessment, it is often difficult to achieve a reliable spatio-temporal representation of rainfall due to a low rain gauge network density. However, quantitative precipitation estimation (QPE) has acquired new prospects with the introduction of weather radars, thanks...

RESUMEN La eficiencia en el uso de los recursos naturales es una prioridad para garantizar la sostenibilidad económica y ambiental de la agricultura. El proyecto Riego-Asesor analiza las relaciones entre la variabilidad climática y las necesidades requeridas en la gestión hídrica agrícola para así diseñar una batería de buenas prácticas de riego en...

Quantitative precipitation estimation covering a certain area has an essential role in many hydrometeorological applications, highlighting the integration of these estimations into early warning systems and using them as a tool for improving nowcasting of flash‐flood and extreme precipitation events. Previous research allowed assessing a quantifica...

The temporal concentration of precipitation may be characterised using several methods. For climate-scale precipitation, concentration measures are usually performed by means of dimensionless indices such as the Gini Index or the Theil Index. For the purposes of this paper, a set of 66,409 daily time series from around the world were analysed to es...

Groundwater resources are typically the main fresh water source in arid and semi-arid regions. Natural recharge of aquifers is mainly based on precipitation; however, only heavy precipitation events (HPEs) are expected to produce appreciable aquifer recharge in these environments. In this work we used daily precipitation and monthly water level tim...

Streamflow and temperature regimes are well-known to influence on the availability of suitable physical habitat for instream biological communities. General Circulation Models (GCMs) have predicted significant changes in timing and geographic distribution of precipitation and atmospheric temperature for the ongoing century. However, differences in...

The present study deals the rainfall spatial variability of a small mountainous catchment, which includes the spatial distribution and variability of convective and stratiform events. This work focuses on the precipitation events with hydrological response in Venero-Claro Basin (Avila, Spain). In this basin of 15km2, flood events of different magni...

This paper addresses the determination of the realized thermal niche and the effects of climate change on the range distribution of two brown trout populations inhabiting two streams in the Duero River basin (Iberian Peninsula) at the edge of the natural distribution area of this species. For reaching these goals, new methodological developments we...

The n-index is defined as the exponent of the power law relating the maximum averaged intensity over given periods of time (e.g. minutes, hours or days) and these periods of averaging. The n-index (between 0 and 1) reports on temporal variability of the rainfall behaviour within an event. This study analyses the n-index around the world and its unc...

This study is aimed at forecasting the changes in the suitability of brown trout habitat (Salmo trutta L.), caused by alterations in the stream temperature and the flow regime under climate change scenarios. The stream temperature and instantaneous flow in several streams in Central Spain were modelled from daily temperature and precipitation data....

Rainfall concentration and drought recurrence are usually studied independently. However, the fractal behavior of the precipitation suggests that there are similarity relations to different time scales between both climatic features. In this paper we have taken a set of 66,409 time series worldwide and have obtained different patterns of similarity...

The Mediterranean coast of Spain often experiences intense rainfall, sometimes reaching remarkable amounts of more than 400 mm in one day. The aim of this work is to study possible changes of extreme precipitation in Spain for this century, simulated from several Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models. Eighteen climate...

A parametric quantile–quantile transformation is used to correct the systematic errors of precipitation projected by regional climate models. For this purpose, we used two new probability distributions: modified versions of the Gumbel and log-logistic distributions, which fit to the precipitation of both wet and dry days. With these tools, the dail...

This study describes a two-step analogue statistical downscaling method for daily temperature and precipitation. The first step is an analogue approach: the “n” days most similar to the day to be downscaled are selected. In the second step, a multiple regression analysis using the “n” most analogous days is performed for temperature, whereas for pr...

The evaluation of two Global Climate Models (GCM, Lehner et al. 2006) projections under the IPCC IS92a emission scenario (mild scenario similar to SRES A1B—IPCC, 1992) indicate that the flood risk increases in Northern, central and Eastern Europe (IPCC, 2007). The increase of the intense short-duration precipitation in most of Europe is likely to l...

Inadequate timber extraction management of forests, cattle farming, abusive recreational practices, and rapid urban expansion are all factors that create significant problems in the Cantabrian area watershed for the sustainable management of the hydrological ecosystem services. These problems, added to the consequences of climate change, are alread...

In climatology, there is difficulty in describing the probability distribution of rainfall because there are many days without precipitation, which usually causes the most likely daily rainfall to be zero. None of the widely used models is able to describe the overall variation of daily precipitation. This article proposes an alternative model for...

Tenerife, the largest of the seven Canary Islands, has the highest elevation of Spain, the Teide volcano (3.718 m. – the third largest volcano in the world from its base). Its climate is hard influenced both for its tropical latitude and for its exposition to the Trade Winds (alisios), which blow from the northeast for almost the whole year. These...

The impacts of global climate change on the Basque coast and the pelagic systems within the southeastern Bay of Biscay are reviewed. Climate projections under greenhouse gas emission scenarios indicate that this area will experience changes in climate throughout the 21st century, including warming of surface air (especially heat wave episodes), int...

The Potential Distribution model can describe at once the probability distribution and temporal distribution of rainfall. It also allows the incorporation of the dependence of the probability with the number of independent stations. This paper analyzes the probability distribution and temporal distribution of extreme rainfall in the Autonomous Comm...

Recently, possible variations of 'gravitational constant' G have been measured, which can be explained by the expansion of the universe. Usually cosmological models are built with "dark energy" in order to explain why the expansion of the universe is not slowing by the gravitational action. In this paper we propose an alternative model to explain t...

Classical gravitation is so similar to the electrostatic that the possible unification has been investigated for many years. Although electromagnetism is formulated now successfully by quantum field theory, this paper proposes a simple approach to describe the electromagnetism from the macroscopic perspective of general relativity. The hypothesis i...

Future climate change will affect aquatic systems on various pathways. Regarding the hydrological cycle, which is a very important pathway, changes in hydrometeorological variables (air temperature, precipitation, evapotranspiration) in first order impact discharges. The fourth report assessment of the Intergovernmental Panel for Climate Change ind...

According to different regional projections of climate change for the 21st century, changes in the mean and extreme precipitation regimes are expected in most of Europe (Christensen et al., 2007). Precipitation extreme events, in particular, can generate important natural hazards and associated social impacts. such as increasing the probability of...

RESUMEN A menudo se habla de precipitación intensa refiriéndose a la acumulación en una hora o en pocos segundos, incluso realizando comparaciones lineales entre ambas. Sin embargo el comportamiento natural de la precipitación hace que sea necesario hablar de una relación no lineal para referirse a cómo cambia la intensidad de la precipitación con...

The analysis of maximum precipitation is usually carried out by using IDF curves (Intensity- Duration-Frequency), which in turn could be expressed as MAI curves (Maximum Average In- tensities). An index "n" has been developed in this work, defined from the exponent obtained when adjusting IDF climatic curves to MAI curves. That index provides infor...