Author: BENJAMIN MARTINEZ LOPEZ

Circulación del Golfo de Mexico inducida por mareas, viento y la corriente de Yucatán

Circulation in the Gulf of Mexico induced by tides, wind and the Yucatan current

Benjamín Martínez López (1998)

"Se utiliza un modelo numérico barotrópico tridimensional para estudiar la circulación del Golfo de México. Se obtienen las corrientes forzadas por la marea, el viento y la Corriente de Yucatán, y se estudia la acción individual y el conjunto de estos forzamientos. Se reproduce satisfactoriamente la circulación y el campo de elevación debidos a la marea. Al forzar el modelo con viento se obtuvo una circulación anticiclónica en la región occidental del Golfo de México, circulación que ha sido asociada con el viento y los giros anticiclónicos provenientes de la región oriental del Golfo de México en otros estudios. Los resultados de este trabajo sugieren que el desprendimiento de remolinos es un proceso principalmente baroclínico. La contribución del flujo barotrópico de la Corriente de Yucatán a la circulación del Golfo de México se restringe a la región oriental de esta cuenca."

"A three-dimensional model is used to study the circulation in the Gulf of Mexico. Currents associated with tides, wind and the Yucatan Current are presented. Each one of these forcings is analyzed by itself and as a combined effect of the three. We were able to closely reproduce the circulation and elevation fields due to the tides. By forcing the model with winds, an anticyclonic circulation is obtained in the western region of the gulf. This feature has been associated in other studies with the local wind forcing and with the anticyclonic gyres generated in the ea;tern part of the gulf. Results of this work suggest that the detachment of the gyres is mainly a baroclinic process. The contribution of the barotropic flux of the Yucatan Current is found to be restricted to the eastern part of the basin."

Article

Golfo de México, Circulación, Modelación numérica, Marea, Gulf of Mexico, Circulation, Numerical model, Tides. CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA FÍSICA (VE R 5603 .04)

Circulación barotrópica y dispersión de contaminantes en el Golfo de México

Benjamín Martínez López (1993)

Se describen los programas desarrollados para el manejo de los protocolos de comunicación entre entidades de la capa de 3 (capa de red), definidos para la interfaz abonado-red de la RDSI. Los programas desarrolados cumplen con la recomendación Q.931 establecida por el CCITT para el punto de referencia S/T. Los programas están hechos para correr en una computadora personal. Fueron desarrollados en lenguaje de programación C e interactúan con los programas de las capas 1 y 2 dentro de un ambiente de multitareas. Estos programas incluyen rutinas para el intercambio de mensajes con la entidad par de capa 3, con la capa 2 y con la entidad de control de llamadas. Dentro de las actividades de las diferentes funciones están: la interpretación de los mensajes recibidos, el envío de mensajes de respuesta, el arrancar o detener temporizadores o la ejecución de acciones al expirar los mismos, la actualización del estado de la máquina de estados finitos asociada con cada llamada y el despliegue en pantalla de los diferentes eventos. Para efectos de prueba se permite al usuario del programa jugar el papel de las capas superiores (entidad de control de llamadas) por medio de la pantalla y el teclado, de tal manera que puede interactuar con la entidad de control de protocolos para generar el intercambio de mensajes definidos en la recomendación anteriormente citada. La parte medular del programa puede ser utilizada en aplicaciones fuera de una computadora personal, ya que no depende, para su buen funcionamiento, del ambiente particular en el que fué probado.

The software developed for handling the communication protocols between Layer 3 entities (network layer), defined for the ISDN user-network interface is hereby described. This software complies with the CCITT recommendation Q.931 for the S/T reference point. This software is intended to run in a personal computer (PC). It is programmed in C language and it interacts with the software of layers 1 and 2 within a multitasking environment. It includes routines for messages interchange with the layer 3 peer entities, with the layer 2 and with the call control entity. Among its functions are: interpretation of received messages, sending of response messages, starting or stopping timers, actualization of the finite state machine associated with each call and the display of the different events. As a part of the test, the user of the program is allowed to play the roll of the upper layers (call control entity) through the screen and the keyboard, so that he can interact with the protocol control entity to generate the message interchange as defined in Q.931. The medullar part of this software may be used in applications outside the personal computer environment, because it does not need services from the PC BIOS or operating system (DOS).

Master thesis

Optical reflectometer, Optical fibers, Semiconductor lasers, Láseres de semiconductor, Fibra óptica, Reflectómetro óptico CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Analysis of the simulated global temperature using a simple energy balance stochastic model

LUIS EFRAIN MORELES VAZQUEZ BENJAMIN MARTINEZ LOPEZ (2016)

This work presents a study of the response of the simulated global temperature variability to additive and multiplicative stochastic parameterizations of heat fluxes, along with a description of the long-term variability in terms of simple autoregressive processes. The Earth’s global temperature was simulated using a globally averaged energy balance climate model coupled to a thermodynamic ocean model. It was found that simple autoregressive processes explain the temperature variability in the case of additive parameterizations; whereas in the case of multiplicative parameterizations, the description of the temperature variability would involve higher order autoregressive processes, suggesting the presence of complex feedback mechanisms originated by the multiplicative forcing. Also, it was found that multiplicative parameterizations produced a rich structure that emulates closely observed climate processes. Finally, a new approach to describe the stability in the steady state of a general one-dimensional stochastic system, through its potential function, was proposed. From an analytical expression of the potential function, further insight into the description of a stochastic system was provided.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Temperature variability stochastic parameterizations autoregressive process steady state potential function

Analysis of the simulated global temperature using a simple energy balance stochastic model

LUIS EFRAIN MORELES VAZQUEZ BENJAMIN MARTINEZ LOPEZ (2016)

This work presents a study of the response of the simulated global temperature variability to additive and multiplicative stochastic parameterizations of heat fluxes, along with a description of the long-term variability in terms of simple autoregressive processes. The Earth’s global temperature was simulated using a globally averaged energy balance climate model coupled to a thermodynamic ocean model. It was found that simple autoregressive processes explain the temperature variability in the case of additive parameterizations; whereas in the case of multiplicative parameterizations, the description of the temperature variability would involve higher order autoregressive processes, suggesting the presence of complex feedback mechanisms originated by the multiplicative forcing. Also, it was found that multiplicative parameterizations produced a rich structure that emulates closely observed climate processes. Finally, a new approach to describe the stability in the steady state of a general one-dimensional stochastic system, through its potential function, was proposed. From an analytical expression of the potential function, further insight into the description of a stochastic system was provided.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Temperature variability stochastic parameterizations autoregressive process steady state potential function

Evaluación psicofisiológica de un grupo traumatizado después del huracán Paulina en Acapulco, México (1997-1998)

Yolanda Olvera López ALEJANDRA CRUZ MARTINEZ BENJAMIN DOMINGUEZ TREJO (2005)

Artículos

Convivir con los riesgos es una de nuestras abilidades evolutivas adaptativas que, en el contexto del tercer mundo son cada día más frecuentes y devastadores. Además de los daños materiales, el impacto emocional después de un desastre debe evaluarse con precisión y rapidez, solo así podrán recibir oportunamente atención especializada quienes lo requieren. Un equipo multidisciplinario realizó evaluaciones psicofisiológicas de campo para determinar el nivel de estrés traumático y ubicar a quienes requirieron atención especializada y a quienes superaron esta experiencia con sus propios recursos emocionales. Las mediciones no-invasivas fisiológicas e inmunológicas (Domínguez, et al., 2001) corroboraron el primer caso y establecieron en el segundo la sensibilidad, el valor pronostico y la viabilidad de estos procedimientos para evaluar y personalizar las acciones de intervención subsecuentes

Living under risk conditions come to be one of our evolutive adaptative, wich has become more frequent and destructive at third world settings. Beyond fast and reliable assessment of material lost, emotional impact must be performed, in order to reach those whom require professional help. A multidisciplinary team perform individualized field psychophysiological and inmmunological assessment (Domínguez, et al., 2001) in order to identify traumatic stress level for those whom need help and those able to go ahead just on her/his own emotional resources. Non-invasive physiological and inmmunological measurements strengthened sensitivity, prognostic and viability value from this procedures wich allow tailoring subsequent intervention actions

Article

MEDICINA Y CIENCIAS DE LA SALUD Desastre Estrés traumático

Cambio climático y estadística oficial

CARLOS GAY GARCIA FRANCISCO ESTRADA PORRUA BENJAMIN MARTINEZ LOPEZ (2010)

Este trabajo presenta un resumen sobre el cambio climático global y sus manifestaciones en México: modificaciones observadas en temperatura, precipitación y nivel del mar, así como algunas de las que se esperan durante este siglo y algunas estimaciones de sus impactos potenciales en la economía del país. Asimismo, se resalta que la escasez y falta de calidad en los registros de datos climáticos para nuestro país es un factor que limita la generación de información necesaria para orientar la toma de decisiones sobre cambio climático.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA cambio climático clima

Economic Impacts of Climate Change on Two Mexican Coastal Fisheries: Implications for Food Security

ALONSO AGUILAR IBARRA ARMANDO SANCHEZ VARGAS BENJAMIN MARTINEZ LOPEZ (2013)

This paper has a twofold objective: First, to estimate the changes in landings value by 2030 for two Mexican coastal fisheries, specifically shrimp and sardine fisheries, as a consequence of climate change; and second, to discuss the implications of such impacts for food security. A dynamic panel model was used for the Mexican fisheries sector, with data from 1990 through 2009. The results suggest that shrimp production will be negatively affected, while in contrast, the sardine fishery is expected to benefit from the increase in temperature. Most losses/gains would be observed in the NW Mexican Pacific, where the fishing sector has an important role in the local economy, representing a risk to food security in both direct and indirect ways.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Monetary estimation climate change Mexico shrimp fishery sardine fishery food security

Cambio climático y estadística oficial

CARLOS GAY GARCIA FRANCISCO ESTRADA PORRUA BENJAMIN MARTINEZ LOPEZ (2010)

Este trabajo presenta un resumen sobre el cambio climático global y sus manifestaciones en México: modificaciones observadas en temperatura, precipitación y nivel del mar, así como algunas de las que se esperan durante este siglo y algunas estimaciones de sus impactos potenciales en la economía del país. Asimismo, se resalta que la escasez y falta de calidad en los registros de datos climáticos para nuestro país es un factor que limita la generación de información necesaria para orientar la toma de decisiones sobre cambio climático.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA cambio climático clima

Economic Impacts of Climate Change on Two Mexican Coastal Fisheries: Implications for Food Security

ALONSO AGUILAR IBARRA ARMANDO SANCHEZ VARGAS BENJAMIN MARTINEZ LOPEZ (2013)

This paper has a twofold objective: First, to estimate the changes in landings value by 2030 for two Mexican coastal fisheries, specifically shrimp and sardine fisheries, as a consequence of climate change; and second, to discuss the implications of such impacts for food security. A dynamic panel model was used for the Mexican fisheries sector, with data from 1990 through 2009. The results suggest that shrimp production will be negatively affected, while in contrast, the sardine fishery is expected to benefit from the increase in temperature. Most losses/gains would be observed in the NW Mexican Pacific, where the fishing sector has an important role in the local economy, representing a risk to food security in both direct and indirect ways.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA Monetary estimation climate change Mexico shrimp fishery sardine fishery food security

A Time-Series Analysis of the 20th Century Climate Simulations Produced for the IPCC’s Fourth Assessment Report

FRANCISCO ESTRADA PORRUA Pierre Perron CARLOS GAY GARCIA BENJAMIN MARTINEZ LOPEZ (2013)

In this paper evidence of anthropogenic influence over the warming of the 20th century is presented and the debate regarding the time-series properties of global temperatures is addressed in depth. The 20th century global temperature simulations produced for the Intergovernmental Panel on Climate Change’s Fourth Assessment Report and a set of the radiative forcing series used to drive them are analyzed using modern econometric techniques. Results show that both temperatures and radiative forcing series share similar time-series properties and a common nonlinear secular movement. This long-term co-movement is characterized by the existence of time-ordered breaks in the slope of their trend functions. The evidence presented in this paper suggests that while natural forcing factors may help explain the warming of the first part of the century, anthropogenic forcing has been its main driver since the 1970’s. In terms of Article 2 of the United Nations Framework Convention on Climate Change, significant anthropogenic interference with the climate system has already occurred and the current climate models are capable of accurately simulating the response of the climate system, even if it consists in a rapid or abrupt change, to changes in external forcing factors. This paper presents a new methodological approach for conducting time-series based attribution studies.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA