EL CAMBIO CLIMATICO Y SU PROYECCIÓN SOBRE EL NIVEL DEL MAR EN LA COSTA DEL PACÍFICO DE PANAMÁ

In order to predict the future sea level increase in the Pacific coast of Panama, the monthly data on sea level of Balboa (Republic of Panamá) from 1909 to 1998 has been examined to define the trend and the rise of the sea-level of the past century. In addition, the data from Balboa has been divided into five periods of twenty years each to be able to estimate the expected rate of change of the trend and total rise of the sea-level by the end of the current century. The sea-level at Balboa has risen about 20 centimeters in the past 100 years. But moreover, the rate of change for Balboa sea –level has constantly increased for each 20 years period indicating 1.70 cm at the beginning of the past century, while gradually increasing to nearly 8 cm at the end of the XX century. Predictions are made that this trend is likely to cause above a 50 cm sea level increase by the end of the XXI century. The global mean sea level has risen globally more than 15 centimeters in the past 100 years, and the climate change is expected to cause a further rise of about 30 centimeters by the year 2050. This warming would cause the sea to rise in two ways: through thermal expansion of ocean water and through discharges of freshwater from melting ice caps and mountain glaciers.  Para poder proyectar el aumento del nivel del mar en Panamá para el final del siglo XXI, se procesó información, de más de noventa años de datos mensuales, del nivel del mar registrado diariamente en el Puerto de Balboa entre 1909 y 1998. Se determinaron las tendencias y las regresiones para este período. En adición, se calcularon las tendencias de anomalías mensuales del nivel del mar a intervalos de veinte años, hasta el presente, para el Puerto de Balboa (Pacífico). Los resultados revelan que el aumento del nivel del mar durante el siglo XX fue de aproximadamente 20 cm para el Pacífico (Puerto de Balboa). Mas aún, el análisis estadístico indica que para la costa pacífica de Panamá el aumento de nivel del mar para cada período de veinte años fue cada vez mayor, variando desde 1.70 cm en los primeros veinte años (1909-1929), hasta cerca de 8 cm en los últimos diez años (1988-1999). Como conclusión, el análisis estadístico proyecta el aumento del nivel del mar en la costa pacifica de Panamá en más de cincuenta centímetros, desde el presente hasta el final del siglo XXI. En la escala global el aumento del volumen de agua de los océanos debido al calentamiento climático fue más de 15 cm en los últimos cien años. Se predice que el cambio climático causará un aumento del nivel del mar de cerca 30 cm para el año 2050, debido al deshielo de los glaciales y por la expansión térmica de la capa superficial del océano

EL AFLORAMIENTO COSTERO Y EL FENÓMENO DE EL NIÑO: IMPLICACIONES SOBRE LOS RECURSOS BIOLÓGICOS DEL PACIFICO DE PANAMÁ

The Panamanian Pacific is under the influence of natural environmental changes, such as the coastal upwelling and manifestation of El Niño. These events can have severe implications for the biological resources. In this study we characterized the hydrological changes in the Gulf of Panama as related to their seasonality and annual variability. The intensity of the upwelling was assessed using sea surface temperature data. We also evaluated the coral genetic diversity for the coral Pocillopora damicornis. There were obvious changes in the hydrological and biological parameters monitored in the Gulf of Panama as result of the upwelling. The historical analysis of upwelling in the Gulf of Panama indicated that the upwelling occurs in pulses related to sea surface temperatures. In conclusion, sea surface temperature is the best quantitative estimate of upwelling intensity in the Gulf of Panama. The electrophoretic analysis of isozymes in the coral Pocillopora damicornis in Panama suggest the existence of a wider genetic diversity in the thermically stable water of the Gulf of Chiriquí and in areas of moderate upwelling such as Iguana Island in the Gulf of Panama. This contrast with the limited genotypic diversity found in areas of strong upwelling such as the Pearl Islands and the Panama Bay.  La costa del Pacífico panameño está bajo la influencia de cambios ambientales naturales, como el afloramiento costero y las manifestaciones del fenómeno de El Niño, que tienen implicaciones sobre los recursos biológicos. Durante este estudio se caracterizaron las variaciones hidrológicas estacionales e interanuales en el Golfo de Panamá, se estimó la intensidad del afloramiento utilizando los datos de la temperatura superficial del mar y se evaluó preliminarmente la diversidad genotípica de los corales. Se observaron cambios notables en la calidad del agua en el Golfo de Panamá como consecuencia del afloramiento. El análisis histórico de los afloramientos en el Golfo de Panamá indica que éstos son pulsativos y con más de dos períodos y asociados a las temperaturas superficiales del mar. La temperatura representa el mejor estimado cuantitativo de la intensidad de afloramiento periódico en el Golfo de Panamá. El análisis electroforético de las isoenzimas del coral Pocillopora damicornis en Panamá sugiere la existencia de una amplia diversidad genética en las áreas térmicamente estables del Golfo de Chiriquí y en áreas de afloramiento moderado como Isla Iguana en el Golfo de Panamá. Lo anterior contrasta con la limitada diversidad de genotipos que tiene la especie en las áreas con fuerte influencia del afloramiento, como en el Archipiélago de Las Perlas y en las islas de la Bahía de Panamá

Quantifying Earth system interactions for sustainable food production via expert elicitation

Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production

Respuesta ambiental en el Pacífico frente a la subducción de la dorsal asísmica de Cocos (Panamá y Costa Rica)

Environmental response in the Pacific to aseismic Cocos Ridge subduction (Panama and Costa Rica). The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic communities, we reconstructed benthic assemblages from Neogene fossiliferous formations in Burica and Nicoya peninsulas of Panama and Costa Rica. Paleoecological and paleoenvironmental conditions were reconstructed by comparing community structure from bulk fossil samples with dredge collections from modern Tropical American seas, using principal component analysis. Our results indicate that during the early Pliocene, before the closing of the Isthmus, some oceanic islands existed with moderate upwelling in the Burica region. After the closure, during the late Pliocene and early Pleistocene the collision of the DAC caused an uplift of the seafloor, where water depth of 2 300m became shallow waters of less than 40m depth. Meanwhile, upwelling intensified in the open ocean the uplift that had formed small islands in coastal areas of Burica, creating protected areas and limiting the upwelling effect that was given in open ocean. The subduction of the DAC continued until the islands were joined to the mainland and gradually disappeared, allowing the return of the upwelling. During the middle Pleistocene a second process of accelerated uplift with speeds of 8m/1 000 years provoked again the elevation of the seafloor and later the elevation of the Talamanca Range. The new range formed a barrier that blocked the passage of the Trade winds, created new ecological conditions and optimized and allowed the growth of the best coral reefs in the coasts of the tropical Eastern Pacific (POT) between Panama and Costa Rica.Con el fin de evaluar el efecto de la Subducción de la Dorsal Asísmica de Cocos (DAC) durante las etapas finales de la formación del Istmo. Realizamos muestreos con bultos en afloramientos fosilíferos en las penínsulas de Burica y Nicoya. Las condiciones paleoecológicas y paleoambientales fueron reconstruidas a partir de la comparación entre la estructura de las comunidades fósiles, con las comunidades modernas dragadas de los mares de Panamá, usando análisis de componentes principales. Los resultados indican que antes del cierre del Istmo, existieron islas oceánicas y un afloramiento moderado en Burica. Posterior al cierre, el choque de la DAC provocó la elevación del fondo marino y las aguas que se encontraban a 2 300m pasaron a 40m. El afloramiento se intensificaba en mar abierto pero la dorsal había formado islas en Burica que limitaban el efecto del afloramiento en la costa. La subducción de la DAC continuó y las islas se unieron gradualmente a tierra firme y desaparecieron, permitiendo el afloramiento. Durante el Pleistoceno medio un segundo proceso de levantamiento acelerado continuó elevando el fondo marino y formó la Cordillera de Talamanca. La cordillera creó una barrera que bloqueó el paso de los vientos Alisios y originó condiciones ecológicas y optimas que permiten el crecimiento de los mejores arrecifes de coral costeros del Pacífico oriental tropical (POT) entre Panamá y Costa Rica

Quantifying Earth system interactions for sustainable food production via expert elicitation

Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production

Options for keeping the food system within environmental limits

The food system is a major driver of climate change, changes in land use, depletion of freshwater resources, and pollution of aquatic and terrestrial ecosystems through excessive nitrogen and phosphorus inputs. Here we show that between 2010 and 2050, as a result of expected changes in population and income levels, the environmental effects of the food system could increase by 50–90% in the absence of technological changes and dedicated mitigation measures, reaching levels that are beyond the planetary boundaries that define a safe operating space for humanity. We analyse several options for reducing the environmental effects of the food system, including dietary changes towards healthier, more plant-based diets, improvements in technologies and management, and reductions in food loss and waste. We find that no single measure is enough to keep these effects within all planetary boundaries simultaneously, and that a synergistic combination of measures will be needed to sufficiently mitigate the projected increase in environmental pressures.</p