Facultad de Ciencias Exactas y Naturales

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A first estimation of tsunami hazard of the Pacific coast of Costa Rica from local and distant seismogenic sources
(Springer, 2021-06-04) Chacon-Barrantes, Silvia; Arozarena-Llopis, Isabel
Costa Rica has been affected by several local and distant tsunamis in the past, but the historical information is scarce and incomplete. Its Pacific coast stretches for over a thousand kilometers, and tsunami hazard has never been evaluated for its full extent. Numerical modeling of tsunami propagation and inundation is a useful tool to assess tsunami hazard, particularly in cases with limited historical information available. Here, we perform a first estimation of tsunami hazard for the Pacific coast of Costa Rica from seismogenic sources, by numerical propagation of 57 local and distant tsunamis to a depth of 20 m. The results of our study identified tsunami sources that are particularly threatening for Costa Rica and determined locations with higher tsunami hazard. For the analysis, the Pacific coast of Costa Rica was divided into segments and subsegments based on differences in continental slope morphology. Subsegments with higher tsunami heights were Southwest Nicoya Peninsula and West Osa Peninsula, and in a lesser extent North Guanacaste, North Nicoya Peninsula, and Central Pacific. Regions with long and gentle slopes and narrow continental shelf were affected by higher tsunami waves, due to more efficient tsunami energy transmission to the shelf and reduced energy loss while traveling through a narrow shelf. On the opposite, steeper continental slopes reflected most of the tsunami energy, causing smaller tsunami heights nearshore, regardless of the shelf width. Nevertheless, other effects played a major role, like curved coastlines that focused tsunami energy, wave refraction, interference, and trapped edge waves. Distant tsunamis dominated the threat, with tsunamis coming from the Tonga-Kermadec and the Colombia-Ecuador Trenches causing the greatest heights due to directivity, and arrival times of about 15 h and 75 min, respectively. Local tsunamis had short arrival times but a localized impact, mainly at the shoreline in front of the generation region but were also affected by tsunami focusing, wave refraction, and edge waves. Outer rise and Osa sources caused the lowest impact within local sources. These results provide a guide for emergency planners to prioritize coastal locations and tsunami sources for tsunami preparedness actions and warning protocols.
Activity of aerial insectivorous bats in two rice fields in the northwestern Llanos of Venezuela
(BioOne Digital Library, 2019-05) Azofeifa Romero, Yara; Estrada-Villegas, Sergio; Mavarez, Jesus; Nassar, Jafet
Abstract. Even though agricultural lands provide abundant food to aerial insectivorous bats (AIB), our understanding of how spatio-temporal factors affect their foraging behavior in these habitats is limited and mostly restricted to temperate regions. In this study, we examined species richness, composition and patterns of activity of AIB in rice fields in the northwestern Llanos of Venezuela. Between 2013 and 2014, we conducted acoustic monitoring of AIB in two rice fields with contrasting forest cover, throughout three phases of the life cycle of this crop (vegetative, reproductive, and ripening), during the dry and rainy season. Out of 108 h recorded, we processed 12,630 files and identified 15 species and 10 sonotypes of AIB from families Molossidae, Mormoopidae, Vespertilionidae, Emballonuridae and Noctilionidae. Molossus molossus and Myotis nigricans showed the highest levels of feeding and general activity across species. The index of general activity (IGA) of AIB was higher above rice fields with more surrounding forest cover, during the dry season and throughout the entire life cycle of the plant. Relative feeding activity (RFA) did not change with respect to forest cover, season or crop phase, but a significant effect of the interaction of these factors was observed on this variable. The response of IGA and RFA to forest cover. season or crop phase was different between M. molossus and M. nigricans and among functional groups. Our results indicate that rice fields in the Venezuelan Llanos can be active feeding grounds for open space and edge-habitat foraging species of insect-feeding bats. Forest patches can promote AIB activity by favoring foraging of 'edge' species above rice fields. Higher general activity of most AIB species during the dry season suggests that rice fields are used more intensively when insect populations decrease in semi-deciduous forest patches around them. Overall, our results suggest that availability of abundant feeding areas to AIB, provided by the rice fields, together with presence of artificial and natural roosts to these bats, could ensure year-round permanence of a rich ensemble of AIB in the rice field-forest landscape in the northwestern Llanos of Venezuela. Some of these species could be the subject of field experiments to test their value in the control of rice's insect pest populations.
Evaluación de la Calidad del Agua Superficial en el cantón de San Pablo de Heredia
(Universidad Nacional (Costa Rica), 2021-06-21) Salas García, Josué; Mena Rivera, Leonardo
Con el pasar de los años, se ha manifestado un incremento significativo en la cantidad de personas que habitan este planeta; a su vez, cada uno desarrolla sus actividades por medio del uso de los recursos naturales. Un manejo desmedido de ellos está propiciando impactos reales tanto para el aire y el suelo, así como el agua; esto a causa de pensamientos enfatizados en la producción y no precisamente al tratamiento de los desechos que conlleva cada actividad (Schneider et al., 2016). El agua es un recurso que vitaliza y aporta energía a los ecosistemas, un buen estado del mismo favorece al desarrollo óptimo de las actividades humanas esto debido a que refuerzan factores tanto climatológicos, sociales y económicos así como los ciclos hidrológicos (Semmens et al., 2011; Manjari, 2014). Lamentablemente, la contaminación trae consigo impactos negativos en los ecosistemas, por ejemplo: una mayor exposición de los cultivos hacia las plagas, enfermedades transmitidas por este medio tanto para humanos como animales, y fenómenos de sequias e inundaciones (Horwitz and Finlayson, 2011; Semmens et al., 2011).
Evaluación de la Gestión de las Aguas Residuales en el Cantón de San Pablo de Heredia
(Universidad Nacional (Costa Rica), 2021-06-21) Mejía Monge, Emilio José; Pérez Salazar, Roy
Actualmente países como los que forman parte de América Latina, El Caribe o de continentes como el asiático y el africano, llamados subdesarrollados o en vías de desarrollo, poseen la problemática de la falta de tratamiento de las aguas residuales o en algunos casos llamadas aguas negras. La depuración no alcanza el 10%, en los países antes mencionados, lo que contrasta con las naciones europeas, los Estados Unidos y Canadá donde las aguas residuales son depuradas por medio de múltiples tratamientos (Avelar, 2011). Parte de la problemática actual, en las naciones subdesarrolladas, es la descarga de aguas residuales a distintos cuerpos de agua, sin ningún tipo de tratamiento, las cuales, pueden ser de tipo doméstico o industrial. Las domésticas son portadoras principalmente de materia fecal mientras que las industriales son poseedoras de una variedad de elementos tóxicos entre ellos metales pesados como el mercurio, cadmio o plomo y desechos de tipo radioactivo. Provocando una reducción en la calidad de vida para la población expuesta, además del daño al ambiente estimulado por las emisiones de gas metano, generadas por las aguas residuales, ya que es un gas de efecto invernadero el cual tiene un potencial de calentamiento 20 veces mayor que el dióxido de carbono (Avelar, 2011).
ICT professional's training programs certification. Synonymous of professional quality, continuous improvement and development
(38th Latin America Conference on Informatics, CLEI 2012 - Conference Proceedings, 2013) Mora Rivera, Sonia; Cabrera Álzate, Sandra
This article presents a summary of the experience in the accreditation process of the informatics engineering careers, from the concepts definition, documents and from the topic evaluation instruments. The article pretends to be an informative and motivational document to awaken the interest in those institutions dedicated to the superior education programs in the informatics area, highlighting the main benefits and details in one of the most important processes of any country's development: the continuous quality improvement of the superior university education. Based on a survey to students and academics of the National University informatics re-accredited career: Information Systems Engineering, it is evident the clear conscience on the accreditation process importance, being the spreading information process of its evolution and the motivation, of the stakeholders, to assume responsibility, key elements of the whole process.
“Impact of the tsunami caused by the Hunga Tonga–Hunga Ha’apai eruption in Costa Rica on 15 January 2022”
(Springer, 2023-05-12) Chacon-Barrantes, Silvia; Rivera Cerdas, Fabio; Murillo Gutiérrez, Anthony
Hunga Tonga–Hunga Ha’apai had a large eruption (VEI 5–6) on 15 January 2022, which caused a tsunami recorded in all ocean basins. Costa Rica has made many advances in tsunami preparation over the past 9 years since the creation of SINAMOT (Sistema Nacional de Monitoreo de Tsunamis, National Tsunami Monitoring System), both on watch and warning protocols and on community preparedness. For the Hunga Tonga–Hunga Ha’apai event, the government declared a low-threat warning, suspending all in-water activities, even though the country did not receive any official warning from PTWC (Pacific Tsunami Warning Center) due to the lack of procedures for tsunamis generated by volcanoes. The tsunami was observed at 24 locations on both the Pacific and Caribbean coasts of Costa Rica, becoming the second most recorded tsunami in the country, after the 1991 Limon tsunami along the Caribbean coast. At 22 of those locations along the continental Pacific coast, observations were made by eyewitnesses, including one collocated with the sea level station at Quepos, which registered the tsunami. At Cocos Island (~ 500 km southwest of the continental Costa Rica, in the Pacific Ocean), several eyewitnesses reported the tsunami at two locations, and it was recorded at the sea level station. The tsunami was also recorded at the sea level station on the Caribbean coast. The tsunami effects reported were a combination of sea level fluctuations, strong currents, and coastal erosion, proving that the response actions were adequate for the size of the tsunami. Tsunami preparedness and the largest waves arriving during a dry season Saturday afternoon allowed the large number of eyewitness reports. This event then increased tsunami awareness in the country and tested protocols and procedures. Still, many people along the coast were not informed of the tsunami during the alert due to their remote location, the short notice of the warning, and a lack of procedures for some communities. There is thus still much work to do, particularly about warning dissemination, a direction in which communities should take an active role.
Inventario de gases de efecto de invernadero debidos al sector desechos, en el cantón de San Pablo de Heredia
(Universida Nacional, 2021-06-21) Sassa-Marín, Jihad; Sasa Marin, Mohammad Jihad
Se presenta en este informe la estimación de los gases de efecto invernadero (GEI) generados por la categoría de inventario correspondiente a residuos sólidos, en el Cantón de San Pablo de Heredia, para el año 2018. En el informe se observan dos estimaciones, una con las condiciones actuales de reciclaje, y otra si no se hubiesen efectuado las campañas de reciclaje de desechos. La estimación de los GEI se realizó de acuerdo a la metodología recomendada por el IPCC en sus guías para el año 2006 “Guidelines for National Greenhouse Gas Inventories”, así como las hojas de cálculo IPCC Waste Model. La información de residuos sólidos, incluyendo su caracterización y cuantificación histórica, fue entregada por la oficina Ambiental de la Municipalidad de San Pablo de Heredia. Además se utilizó el estudio elaborado por NAMA, e información procedente del INEC.
Microclimate of developing tubular leaves used as roost sites by bats
(BioOne Digital Library, 2019-05) Pérez - Cárdenas Nathalia; Porras - Brenes, Katherine; Auccacusi-Choque, Leydi V.; Suárez Torres, Joanna Jazmin; Brooks Laverdeza, Rosa María; Chaverri, Gloriana
Abstract. Roosts are critical for the reproduction and survival of bats and many species spend a significant portion of their lives in them; thus, individuals should carefully select sites that reduce predation risk while providing ideal microclimatic conditions. Many studies have determined that bats select warmer and more humid roosts in temperate regions, but few studies have determined if roosts selected by tropical species also provide suitable conditions. In this study we compare temperature and humidity within and outside furled tubular leaves of plants in the order Zingiberales, which are used by several tropical species as roost-sites, to determine if these structures provide microclimatic advantages to bats. We found very small differences between the internal and external temperatures of tubular leaves, and the difference further decreased as leaves developed. However, we found large differences in humidity within the tubular leaf compared to external conditions. which were strongly dependent on a leaf's diameter and genus. The internal humidity was often 20% above the external, particularly when leaves were narrower, and tubular leaves in the genus Heliconia were more humid than those in the genus Calathea. Our findings suggest that. despite being fairly exposed structures, furled tubular leaves provide suitable microclimatic conditions for tropical species.
New records of historical tsunamis obtained from Costa Rican newspapers
(American Geophysical Union, 2020-12-14) Chacon-Barrantes, Silvia; Murillo Gutiérrez, Anthony; Rivera Cerdas, Fabio
Costa Rica has few records of historical tsunamis, due to traditionally low populated coasts and moderate tsunami potential, among other reasons. As part of the writing of the first tsunami catalog of Costa Rica, the authors performed an extensive search of reports that can be associated with tsunamis on newspapers from 1851 to 1992, at the Costa Rica National Library database (SINABI, 2020). The dates searched were related to 25 earthquakes originated in Costa Rica, Nicaragua and Panamá, from 1851 to 1992, with Mw > 6.0 or MMI > VII. Also, four remote tsunamis were considered: 1906 Colombia, 1952 Kamchatka, 1960 Chile and 1964 Alaska. For each event, we searched newspapers starting from the day after the earthquake until 15 days after. We found reports that refer certainly to tsunamis for the 1906 Colombia and 1941 Osa (5 December) earthquakes. For both tsunamis there were records from witnesses at other locations in Costa Rica, and the 1941 tsunamis (5 and 6 December) were the first recorded in tide gauges in Costa Rica. We also found entries on newspapers that might refer to tsunamis but cannot be conJrmed, linked to 1916 Papagayo, 1916 Bocas del Toro and 1924 Tárcoles earthquakes. Bocas del Toro tsunami was registered in Panamá; the other two earthquakes were caused by subduction in the Middle America Trench and thus very likely caused tsunamis; although there are no records linked to them. These three events were classified as probable tsunamis for the catalog. For the 1905 Nicoya Gulf earthquake, we found a reference of coastal landslides that might be related to the tsunami experienced in Cocos Island. Here we geolocalize the entries found and discuss them in terms of what is known from the respective earthquake and tsunami. We could not Jnd any information in the newspapers related to the tsunamis: 1950 Nicoya, 1952 Kamchatka, 1960 Chile, 1964 Alaska,1983 Golfito, 1990 Cóbano, 1991 Valle de la Estrella and 1992 Nicaragua, despite they were recorded at tide gauges and/or observed by witnesses. This was particularly unexpected for the tsunamis of 1991 and 1992, as they were the largest recorded at Caribbean and Pacific coasts of Costa Rica, respectively. The reports of abnormal sea level changes in newspapers provided a valuable complement to the records from other sources, and for some events are the only record available.
Numerical Simulations of the 1991 Limón Tsunami, Costa Rica Caribbean Coast
(Pure and Applied Geophysics vol.174 2945-2959 2017, 2017) Chacon-Barrantes, Silvia; Zamora, Natalia
The second largest recorded tsunami along the Caribbean margin of Central America occurred 25 years ago. On April 22nd, 1991, an earthquake with magnitude Mw 7.6 ruptured along the thrust faults that form the North Panama ́ Deformed Belt (NPDB). The earthquake triggered a tsunami that affected the Caribbean coast of Costa Rica and Panama ́ within few minutes, generating two casualties. These are the only deaths caused by a tsunami in Costa Rica. Coseismic uplift up to 1.6 m and runup values larger than 2 m were measured along some coastal sites. Here, we consider three solutions for the seismic source as initial conditions to model the tsunami, each considering a single rupture plane. We performed numerical modeling of the tsunami propagation and runup using NEOWAVE numerical model (Yamazaki et al. in Int J Numer Methods Fluids 67:2081–2107, 2010, doi: 10.1002/fld.2485 ) on a system of nested grids from the entire Caribbean Sea to Limo ́n city. The modeled surface deformation and tsunami runup agreed with the measured data along most of the coastal sites with one preferred model that fits the field data. The model results are useful to determine how the 1991 tsunami could have affected regions where tsunami records were not preserved and to simulate the effects of the coastal surface deformations as buffer to tsunami. We also performed tsunami modeling to simulate the consequences if a similar event with larger magnitude Mw 7.9 occurs offshore the southern Costa Rican Caribbean coast. Such event would generate maximum wave heights of more than 5 m showing that Limo ́n and northwestern Panama ́ coastal areas are exposed to moderate-to-large tsunamis. These simulations considering historical events and maximum credible scenarios can be useful for hazard assessment and also as part of studies leading to tsunami evacuation maps and mitigation plans, even when that is not the scope of this paper.
Nutritional and Chemical Composition of the Costa Rican Guava (Psidium friedrichsthalianum [O. Berg] Nied): An Underexploited Edible Fruit with Nutritional and Industrial Potential
(ACS Publications, 2021-10-22) Muñoz Arrieta, Rodrigo; Esquivel-Alvarado, Daniel; Alfaro-Viquez, Emilia; Reed, Jess D.; Álvarez Valverde, Víctor; Rodríguez Salazar, Massiel; Rodríguez, Gerardo; Reed, Jess D.
The nutritional and chemical composition of the Costa Rican guava was evaluated by proximate analysis, amino acids, sugars, organic acids, vitamins, and minerals composition. The fatty acid and proanthocyanidin (PAC) profiles were also determined. Proximate analysis showed that Costa Rican guava has a moisture content of 82.10 g/100 g, crude fat 0.91 g/100 g, protein 0.51 g/ 100 g, dietary fiber 7.10 g/100 g, and carbohydrate 8.48 g/100 g. Arginine is the predominant essential amino acid. Sucrose and citric acid are the predominant sugar and organic acid, respectively. Apart from ascorbic acid, niacin is the predominant vitamin. Sodium and calcium are the predominant minerals. Linoleic and α-linolenic acids are the predominant fatty acids. Costa Rican guava PAC contain exclusively B-type interflavan bonds with molecular masses typical of (epi)catechin monomers. To the best of our knowledge, this is the first study to provide a detailed description of the nutritional and chemical composition of the Costa Rican guava.
Propuesta para la valoración de opciones de saneamiento por humedales artificiales
(Universidad Nacional (Costa Rica), 2021-06-21) Alfaro-Chinchilla, Carolina
The 2017 México Tsunami Record, Numerical Modeling and Threat Assessment in Costa Rica
(Springer, 2018-03-30) Chacón-Barrantes, Silvia
An Mw 8.2 earthquake and tsunami occurred off- shore the Pacific coast of Me´xico on 2017-09-08, at 04:49 UTC. Costa Rican tide gauges have registered a total of 21 local, regional and far-field tsunamis. The Quepos gauge registered 12 tsunamis between 1960 and 2014 before it was relocated inside a harbor by late 2014, where it registered two more tsunamis. This paper analyzes the 2017 Me´xico tsunami as recorded by the Quepos gauge. It took 2 h for the tsunami to arrive to Quepos, with a first peak height of 9.35 cm and a maximum amplitude of 18.8 cm occurring about 6 h later. As a decision support tool, this tsunami was modeled for Quepos in real time using ComMIT (Community Model Interface for Tsunami) with the finer grid having a resolu- tion of 1 arcsec (* 30 m). However, the model did not replicate the tsunami record well, probably due to the lack of a finer and more accurate bathymetry. In 2014, the National Tsunami Moni- toring System of Costa Rica (SINAMOT) was created, acting as a national tsunami warning center. The occurrence of the 2017 Me´xico tsunami raised concerns about warning dissemination mechanisms for most coastal communities in Costa Rica, due to its short travel time.

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