Escenarios futuros de eventos extremos de precipitación y temperatura en México

Future changes of precipitation and temperature extremes in Mexico

Ernesto Ramos Esteban (2024, [Tesis de maestría])

Diferentes estudios a escala mundial indican un incremento en frecuencia de eventos climáticos extremos debido al calentamiento global y sugieren que podrían intensificarse en el futuro. El objetivo de este trabajo es analizar los posibles cambios de 12 índices climáticos extremos (ICE) de precipitación y temperatura en 15 regiones de México, el sur de los Estados Unidos y Centroamérica para un período histórico (1981-2010), un futuro cercano (2021-2040), un futuro intermedio (2041-2060) y un futuro lejano (2080-2099). Se utilizó el reanálisis ERA5 como referencia en la evaluación histórica de los modelos climáticos globales (MCG) y para las proyecciones se analizaron los ICE de diez MCG del Proyecto de Intercomparación de Modelos Climáticos, fase 6 (CMIP6), de acuerdo con dos escenarios de Vías Socioeconómicas Compartidas (SSPs), uno de bajas emisiones (SSP2-4.5) y otro de altas emisiones (SSP3-7.0). Los MCG reproducen muy bien los índices extremos de temperatura histórica y los días consecutivos secos, pero subestiman la lluvia promedio y la lluvia extrema en las zonas más lluviosas desde el centro de México hasta Centroamérica. Históricamente, se observaron tendencias positivas de las temperaturas extremas (TXx y TNn) en todas las regiones, pero sólo en algunas regiones fueron significativas, mientras que los índices de lluvia extrema (R95p, R10mm y R20mm) presentaron tendencias negativas, pero pequeñas. Las proyecciones indican que las temperaturas extremas podrían seguir incrementándose en el futuro, desde 2° C hasta 5° C a mitad y final de siglo, respectivamente. La contribución de la precipitación extrema arriba del percentil 95 (R95p) se podría incrementar entre un 10 % y 30 %, especialmente en la región subtropical, mientras que la precipitación podría disminuir en las regiones tropicales. Este estudio es el primero que analiza los cambios futuros de índices extremos del CMIP6 a escala regional (en 15 regiones) de México, el sur de Estados Unidos y Centroamérica.

Global-scale studies indicate an increase in the frequency of extreme weather events due to global warming and suggest that they could further intensify in the future. This study aims to assess potential changes in 12 extreme climate indices (ECI) related to precipitation and temperature in 15 regions in Mexico, the southern United States, and Central America for different periods: a historical period (1981-2010), a near future (2021-2040), an intermediate future (2041-2060), and a far future (2080-2099). The ERA5 reanalysis was used as a reference for the historical evaluation of global climate models (GCMs), and ECI from ten GCMs of phase 6 (CMIP6) from the Coupled Model Intercomparison Project were employed for the projections and examined under two Shared Socioeconomic Pathways (SSPs) scenarios, one characterized by low emissions (SSP2-4.5) and another representing high greenhouse gas emissions (SSP3-7.0). The GCMs reproduce historical extreme temperature indices and consecutive dry days very well. However, they underestimate average and extreme rainfall from central Mexico to Central America in the wetter areas. Historically, positive trends in extreme temperatures (TXx and TNn) were observed across all regions. However, statistical significance was only present in certain regions, while extreme rainfall indices (R95p, R10mm, and R20mm) exhibited small negative trends. The projections suggest that extreme temperatures could continue to increase in the future, from 2°C to 5°C by the mid and late century, respectively. The contribution of extreme precipitation above the 95th percentile (R95p) could increase by 10% to 30%, particularly in the subtropical regions, while precipitation might decrease in tropical regions. This study is the first to analyze future changes in extreme indices from CMIP6 at a regional scale (across 15 regions) in Mexico, the southern United States, and Central America.

Centroamérica, CMIP6, escenarios SSP, extremos climáticos, intercomparación de modelos climáticos, México Central America, climate extremes, CMIP6, intercomparison of climate models, Mexico, SSP scenarios CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA FÍSICA (VE R 5603 .04) OCEANOGRAFÍA FÍSICA (VE R 5603 .04)

Optimizing nitrogen fertilizer and planting density levels for maize production under current climate conditions in Northwest Ethiopian midlands

Kindie Tesfaye Dereje Ademe Enyew Adgo (2023, [Artículo])

This study determined the most effective plating density (PD) and nitrogen (N) fertilizer rate for well-adapted BH540 medium-maturing maize cultivars for current climate condition in north west Ethiopia midlands. The Decision Support System for Agrotechnology Transfer (DSSAT)-Crop Environment Resource Synthesis (CERES)-Maize model has been utilized to determine the appropriate PD and N-fertilizer rate. An experimental study of PD (55,555, 62500, and 76,900 plants ha−1) and N (138, 207, and 276 kg N ha−1) levels was conducted for 3 years at 4 distinct sites. The DSSAT-CERES-Maize model was calibrated using climate data from 1987 to 2018, physicochemical soil profiling data (wilting point, field capacity, saturation, saturated hydraulic conductivity, root growth factor, bulk density, soil texture, organic carbon, total nitrogen; and soil pH), and agronomic management data from the experiment. After calibration, the DSSAT-CERES-Maize model was able to simulate the phenology and growth parameters of maize in the evaluation data set. The results from analysis of variance revealed that the maximum observed and simulated grain yield, biomass, and leaf area index were recorded from 276 kg N ha−1 and 76,900 plants ha−1 for the BH540 maize variety under the current climate condition. The application of 76,900 plants ha−1 combined with 276 kg N ha−1 significantly increased observed and simulated yield by 25% and 15%, respectively, compared with recommendation. Finally, future research on different N and PD levels in various agroecological zones with different varieties of mature maize types could be conducted for the current and future climate periods.

Maize Model Planting Density CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE MODELS SPACING NITROGEN FERTILIZERS YIELDS

“Mexico half way of making”: Carlos Chávez and the foundation of the National Institute of Fine Arts (INBA) (1945-1947)

Ana Garduño (2023, [Artículo, Artículo])

I am focusing on the interaction between a cultural agent, Carlos Chávez, and the government elite, related to the circumstances of the enunciation of a public and official organism, INBA (The National Institute of Fine Arts), because I assume that political relations are fundamental to understand a process that endorsed the official culture as an appendage of politics. In spite of its relevance, this subject has not been studied. Based on archival documentation (at the National Archive of Mexico and the archive of INBA) I am examining the cultural policies derived from the foundation of INBA. Due to the current pandemic situation, it was not possible to consult other documental sources. I am formulating that the concept of “high culture” was at the core of a wider conflict between governmental interests and those of representative social actors, and I conclude that this obstacle would have conferred a major political and symbolical importance to the Institute, and consequently, would restrict its budget.

Carlos Chávez INBA Agentes culturales Políticas institucionales Centralización artística HUMANIDADES Y CIENCIAS DE LA CONDUCTA HUMANIDADES Y CIENCIAS DE LA CONDUCTA Foundation of the National Institute of Fine Arts in Mexico (INBA), Cultural agents Institutional policies Artistic centralization

Global surveillance summary

David Hodson (2022, [Objeto de congreso])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA WHEAT RUSTS SURVEILLANCE SYSTEMS

Agricultural emissions reduction potential by improving technical efficiency in crop production

Arun Khatri-Chhetri Tek Sapkota sofina maharjan Paresh Shirsath (2023, [Artículo])

CONTEXT: Global and national agricultural development policies normally tend to focus more on enhancing farm productivity through technological changes than on better use of existing technologies. The role of improving technical efficiency in greenhouse gas (GHG) emissions reduction from crop production is the least explored area in the agricultural sector. But improving technical efficiency is necessary in the context of the limited availability of existing natural resources (particularly land and water) and the need for GHG emission reduction from the agriculture sector. Technical efficiency gains in the production process are linked with the amount of input used nd the cost of production that determines both economic and environmental gains from the better use of existing technologies. OBJECTIVE: To assess a relationship between technical efficiency and GHG emissions and test the hypothesis that improving technical efficiency reduces GHG emissions from crop production. METHODS: This study used input-output data collected from 10,689 rice farms and 5220 wheat farms across India to estimate technical efficiency, global warming potential, and emission intensity (GHG emissions per unit of crop production) under the existing crop production practices. The GHG emissions from rice and wheat production were estimated using the CCAFS Mitigation Options Tool (CCAFS-MOT) and the technical efficiency of production was estimated through a stochastic production frontier analysis. RESULTS AND CONCLUSIONS: Results suggest that improving technical efficiency in crop production can reduce emission intensity but not necessarily total emissions. Moreover, our analysis does not support smallholders tend to be technically less efficient and the emissions per unit of food produced by smallholders can be relatively high. Alarge proportion of smallholders have high technical efficiency, less total GHG emissions, and low emissions intensity. This study indicates the levels of technical efficiency and GHG emission are largely influenced by farming typology, i.e. choice and use of existing technologies and management practices in crop cultivation. SIGNIFICANCE: This study will help to promote existing improved technologies targeting GHG emissions reduction from the agriculture production systems.

Technical Efficiency Interventions CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MITIGATION PRODUCTIVITY CROP PRODUCTION GREENHOUSE GAS EMISSIONS

Estructura del basamento de la Cuenca Farallón al Sur del Golfo de California, mediante la interpretación de datos potenciales y sísmicos

Basement structure of the Farallon Basin at the south of the Gulf of California, through the interpretation of seismic and potential field data

Marco Antonio Bartens Olortegui (2013, [Tesis de maestría])

El Golfo de California es un rift continental activo con apertura oblicua y desplazamiento lateral derecho y es uno de los pocos ejemplos de un rift continental en la fase inicial donde los procesos de apertura activa se pueden estudiar a lo largo de un rift completo. En este escenario, establecer el límite entre basamento continental y oceánico es clave para entender los mecanismos tectónicos que actúan en esta etapa inicial del rift. Desafortunadamente, esta también es una tarea difícil debido a la presencia de corteza oceánica de nueva creación. El objetivo de este trabajo es el de identificar, delimitar y estimar espesores de la corteza oceánica y corteza continental en la cuenca Farallón. Para ellos se utilizaron datos de sísmica de reflexión multicanal 2D de alta resolucion tomados durante la expedicion Ulloa 2006, datos de anomlías gravimetricas tomados de la base de datos de la gravedad marina global obtenida por altimetría de radar relocalizada de los satélites Geosat y ERS-1. Para su interpretación se realizó modelado gravimetrico bidimensional a lo largo de cada perfil sísmico, seguido por una inversión 3D de los datos potenciales del área de la cuenca Farallón restringidos por los perfiles sísmicos interpretados. La corteza de característica oceánica se sitúa en el centro de la cuenca y se identifica principalmente por la concavidad de sus estructuras, interpretadas como sills en las secciones sísmicas, y por la elevada magnitud de la anomalía de Bouguer en el área. La corteza continental se localiza en los margenes oeste y este de la cuenca y se reconoce por la continuidad del reflector correspondiente y el significativo decremento de la anomalía de Bouguer. Tambien se identificaron: una corteza de naturaleza volcánica en el Macizo Farallón Sur (asociado a un reflector sísmico discontinuo de gran amplitud) y dos capas sobreyacientes de sedimentos, la más profunda afectada aparentemente por intrusiones magmáticas. Las profundidades interpretadas con los modelos gravimétricos indican que se tiene una corteza oceánica delgada al centro de la cuenca, con espesores mínimos de 2.5 km en el eje sur abandonado y 3 km en el eje de la dorsal, así como una corteza continental que se va engrosando gradualmente hacia el continente.

The Gulf of California is an active continental rift with an oblique and dextral opening displacement and it is one of the few examples of an initiating continental rift where active opening processes can be studied along a complete rift. In this scenary, establishing the boundary between continental and oceanic basement holds the key to fully understand the tectonic mechanisms acting on this initial rifting stage. Unfortunately, this is also a challenging task due to the presence of oceanic crust of new creation. The aim of this work is to identify, delineate and estimate the thickness of oceanic and continental crusts in the Farallón basin. For this purpose, they were used high-resolution 2D multichannel seismic reflection data from the Ulloa’s 2006 expedition along with gravity anomaly data from the global marine gravity database obtained by repositioned radar altimetry from Geosat and ERS-1 satellites. For their interpretation, two-dimensional gravity modeling was carried out along each seismic profile, followed by 3D inversion of potential field data from the Farallón basin area as constrained by the interpreted seismic profiles. The oceanic-like crust was located at the centre of the basin and is mainly identified by the concavity of their structures, interpreted as sills in the seismic sections, and the highamplitude of the Bouguer anomaly in the area. The continental crust is located in the western and eastern margins of the basin and it is distinguished by the relevant reflector’s continuity and the significant decrease of the Bouguer anomaly. They were also identified: a volcanic crust at the south of the Farallón Massif (associated to a prominent discontinuous seismic reflector) and two overlying sedimentary layers, the deepest one apparently affected by magmatic intrusions. The interpreted depths from the gravity models indicate that there is a thin oceanic crust at the center of the basin, with minimum thicknesses of 2.5 km in the abandoned south axis and 3 km in the dorsal axis, as well as a continental crust that gradually thickens towards the continent.

sísmica de reflexión, anomalía gravimétrica, Cuenca Farallón, Golfo de California seismic reflection, gravity anomaly, Farallon Basin, Gulf of California CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOFÍSICA SISMOLOGÍA Y PROSPECCIÓN SÍSMICA SISMOLOGÍA Y PROSPECCIÓN SÍSMICA

La organización social de los frontereños. De las juntas vecinales al ayuntamiento en Baja California durante el siglo XIX

Abraham Uribe Núñez (2024, [Tesis de doctorado])

En septiembre de 1876, el presidente municipal Manuel A. punto Ferrer, escribió una carta al presidente de México Sebastián Lerdo de Tejada, en la cual describió que en el pueblo minero de Real del Castillo habían campamentos reciente improvisados por algunos colonos mexicanos, estadounidenses y europeos, A diferencia de otras localidades del partido norte de baja California que estaban habitados por una diversidad de pueblos originarios y frontereños, un gentilicio adoptado por un conjunto de familias descendientes de los antiguos soldados misionales y algunos indios neófitos agrupados en los pueblos de misión fundados por la orden de los dominicanos en las postrimerías del siglo XVIII, pero poco antes del abandono de los frailes durante el fenecimiento de las misiones, la jura de la independencia y la secularización liberal e inicios del siglo XXI, asumieron El dominio territorial en esta demarcación que consolidaron con la instauración de ranchos que producían recursos limitados y provenientes de las ganaderías de libre pastoreo y agricultura en tierras de panllevar.

Frontera México-Estados Unidos -- Condiciones Sociales Baja California -- Condiciones Sociales -- Siglo XIX CIENCIAS SOCIALES HISTORIA HISTORIA

Vibrissa growth rate in California sea lions based on environmental and isotopic oscillations

MARTHA PATRICIA ROSAS HERNANDEZ (2018, [Artículo])

Pinniped vibrissae provide information on changes in diet at seasonal and annual scales; however, species-specific growth patterns must first be determined in order to interpret these data. In this study, a simple linear model was used to estimate the growth rate of vibrissae from adult female California sea lions (Zalophus californianus) from San Esteban Island in the Gulf of California, Mexico. The δ15N and δ13C values do not display a marked oscillatory pattern that would permit direct determination of the time period contained in each vibrissa; thus, time (age) was calculated in two ways: 1) based on the correlation between the observed number of peaks (Fourier series) in the δ15N profile and the length of each vibrissa, and 2) through direct comparison with the observed number of peaks in the δ15N profile. Cross-correlation confirmed that the two peaks in the δ15N profile reflected the two peaks in the chlorophyll-a concentration recorded annually around the island. The mean growth rate obtained from the correlation was 0.08 ± 0.01 mm d-1, while that calculated based on the observed number of peaks was 0.10 ± 0.05 mm d-1. Both are consistent with the rates reported for adult females of other otariid species (0.07 to 0.11 mm d-1). Vibrissa growth rates vary by individual, age, sex, and species; moreover, small differences in the growth rate can result in significant differences over the time periods represented by the isotopic signal. Thus, it is important to assess this parameter on a species-by-species basis. © 2018 Rosas-Hernández et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

carbon, nitrogen, animal, California, chemistry, diet, female, island (geological), Mexico, Otariidae, physiology, Animals, California, Carbon Isotopes, Diet, Female, Islands, Mexico, Nitrogen Isotopes, Sea Lions BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA INMUNOLOGÍA INMUNOLOGÍA

Using an incomplete block design to allocate lines to environments improves sparse genome-based prediction in plant breeding

Osval Antonio Montesinos-Lopez ABELARDO MONTESINOS LOPEZ RICARDO ACOSTA DIAZ Rajeev Varshney Jose Crossa ALISON BENTLEY (2022, [Artículo])

Genomic selection (GS) is a predictive methodology that trains statistical machine-learning models with a reference population that is used to perform genome-enabled predictions of new lines. In plant breeding, it has the potential to increase the speed and reduce the cost of selection. However, to optimize resources, sparse testing methods have been proposed. A common approach is to guarantee a proportion of nonoverlapping and overlapping lines allocated randomly in locations, that is, lines appearing in some locations but not in all. In this study we propose using incomplete block designs (IBD), principally, for the allocation of lines to locations in such a way that not all lines are observed in all locations. We compare this allocation with a random allocation of lines to locations guaranteeing that the lines are allocated to

the same number of locations as under the IBD design. We implemented this benchmarking on several crop data sets under the Bayesian genomic best linear unbiased predictor (GBLUP) model, finding that allocation under the principle of IBD outperformed random allocation by between 1.4% and 26.5% across locations, traits, and data sets in terms of mean square error. Although a wide range of performance improvements were observed, our results provide evidence that using IBD for the allocation of lines to locations can help improve predictive performance compared with random allocation. This has the potential to be applied to large-scale plant breeding programs.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA Bayes Theorem Genome Inflammatory Bowel Diseases Models, Genetic Plant Breeding

Impact of automation on enhancing energy quality in grid-connected photovoltaic systems

Virgilio Alfonso Murillo Rodríguez NOE VILLA VILLASEÑOR José Manuel Robles Solís OA Guirette-Barbosa (2023, [Artículo])

Rapid growth in the integration of new consumers into the electricity sector, particularly in the industrial sector, has necessitated better control of the electricity supply and of the users’ op-erating conditions to guarantee an adequate quality of service as well as the unregulated dis-turbances that have been generated in the electrical network that can cause significant failures, breakdowns and interruptions, causing considerable expenses and economic losses. This research examines the characteristics of electrical variations in equipment within a company in the industrial sector, analyzes the impact generated within the electrical system according to the need for operation in manufacturing systems, and proposes a new solution through automation of the regulation elements to maintain an optimal system quality and prevent damage and equipment failures while offering a cost-effective model. The proposed solution is evaluated through a reliable simulation in ETAP (Energy Systems Modeling, Analysis and Optimization) software, which emulates the interaction of control elements and simulates the design of electric flow equipment operation. The results demonstrate an improvement in system performance in the presence of disturbances when two automation schemes are applied as well as the exclusive operation of the capacitor bank, which improves the total system current fluctuations and improves the power factor from 85.83% to 93.42%. Such a scheme also improves the waveform in the main power system; another improvement result is when simultaneously operating the voltage and current filter together with the PV system, further improving the current fluctuations, improving the power factor from 85.83% to 94.81%, achieving better stability and improving the quality of the waveform in the main power grid.

This article belongs to Special Issue Advances and Optimization of Electric Energy System.

Power quality Capacitor bank Voltage and current filter Photovoltaic system INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS