The aim of this study was to classify and characterize the climate of the Pampas, a vast region in the centre of Argentina. Due to its territorial extension, a climatic zoning of the region was performed, based on the topography and the most relevant climatological parameters. Climate data from 33 stations of the National Meteorological Service were analysed considering the period 1960–2010. A cluster analysis from the hierarchical method of Ward with an interval squared Euclidean distance as a measure of dissimilarity was applied. The obtained clusters responded to the north–south temperature gradient of the Pampas, influenced by geographical features such as the Tandilia and Ventania hills in Buenos Aires Province and the Pampean hills in Córdoba. Precipitation had a northeast–southwest gradient, and the influence of the arid southwest diagonal of the Pampas was appreciated by determining a semi‐arid environment. The proximity to the sea marked the average humidity values, whereas the winds of strong intensity were registered in the south and west of the region. On the other hand, the standard precipitation index was calculated to identify wet and dry cycles in each cluster. It allowed to characterize these events considering frequency, periodicity, duration and intensity, resulting in the definition of eight climatic subregions.

RESUMEN. La Región

The south of , as most of Argentina, is a semiarid region. Its economy is based on rain-fed agriculture and livestock. Traditionally, the climate has been studied considering the analyses of monthly and annual climate parameters, but there is evidence that in this type of areas, the short-term climatic events have a substantial impact on the climate. Therefore, this study aimed at developing a climate regionalization from the analysis of daily temperature and precipitation extremes in the south of the Pampas for the period 1970-2017. Subsequently, it focuses on analyzing both trends and breakpoints of these events in the different sub-climates. To do so, we applied a Cluster-based Principal Component Analyses with a Ward hierarchical supervised method to generate a climate regionalization considering 29 daily extreme climatic indices and the elevation. We identify four sub-regions, and we analyzed trends during 1970-2017, and in the two-time series defined by applying breakpoints. Both minimum and maximum temperatures and precipitation had structural changes in the last 15 years, exposing the region to warming and dryness trends. The maximum temperature increases 0.5ºC, while precipitation decreases 30 mm. The short-term climate variability allows us to identify areas climatically more detailed and to conclude that the south of the Pampas is characterized by its high dependency on short-term climatic events. Regionalización y tendencias climáticas basadas en eventos extremos térmicos y pluviométricos diarios en el sur de la Región Pampeana (Argentina)RESUMEN. El sur es, al igual que la mayor parte de Argentina, una región semiárida. Su economía se basa en la agricultura de secano y la ganadería. Tradicionalmente, el clima Ferrelli et al. 394Cuadernos de Investigación Geográfica 45 (1), 2019, pp. 393-416 ha sido estudiado considerando los eventos térmicos y pluviométricos mensuales y anuales. Sin embargo, existe evidencia científica de que los eventos climáticos a corto plazo (diarios) tienen un impacto sustancial en el clima. El objetivo de este trabajo es desarrollar una regionalización climática a partir del análisis de las temperaturas y precipitaciones diarias extremas en el sur de la Región Pampeana durante el período 1970-2017. Complementariamente, este trabajo se enfoca en analizar las tendencias de estos eventos en cada sub-clima durante dos períodos de tiempo de la serie 1970-2017. Para generar la regionalización, aplicamos un Análisis de Componentes Principales y un Análisis de Conglomerados utilizando el método supervisado de Ward, considerando 29 índices climáticos extremos diarios y la elevación. Como resultado obtuvimos cuatro subregiones. Además, analizamos la tendencia de los 29 índices climáticos extremos diarios durante el período 1970-2017 y en dos sub-series dentro de este período definidas mediante la aplicación de puntos de interrupciones o cambios estructurales. En el sur de la región Pampeana, la temperatura y la precipitación presentaron cambios estructurales en los últimos 15 años, lo q...

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Spatial and temporal analysis of the LST-NDVI relationship for the study of land cover changes and their contribution to urban planning in Monte Hermoso, Argentina AbstractThe aim of this work was to study the spatial distribution of Land Surface Temperature (LST) and its relationship with diverse urban land covers and the Normalized Difference Vegetation Index (NDVI). The study area was Monte Hermoso city, which is located in the southwest of Buenos Aires province, Argentina. To obtain the LST and NDVI parameters, satellite images from LANDSAT 5 TM and LANDSAT 7 ETM+ sensors were seasonally processed for the period 2008-2012. Visual interpretation techniques and empirical intervention were applied to design an urban land cover map on which LST and NDVI were analyzed by tracing four transects oriented in latitudinal and longitudinal directions. Each urban cover presented a particular behavior of these parameters. Furthermore, significant results for the relationship between LST and NDVI were observed (with α 0.1 and 0.05) with R 2 , Pearson, and Spearman indices values higher than 0.7. Finally, LST variation in diverse land covers was observed as a consequence of urban growth and the alteration of the vegetation coverage. Therefore, it was concluded that the spatial and temporal variation of LST values may indicate modifications in urban land covers. The information obtained in this study would be a useful tool to guide future urban management studies and policies. Keywords: Land Surface Temperature (LST); Normalized Difference Vegetation Index (NDVI); seasonal distribution; satellite imagery processing; Monte Hermoso Resum. Anàlisi espacial i temporal de la relació TST-NDVI per a l'estudi dels canvis de cobertura del sòl i la seva contribució per a la planificació urbana (Monte Hermoso, Argentina)L'objectiu d'aquesta investigació va ser estudiar la distribució espacial de la temperatura de superfície terrestre (TST), la seva relació amb diferents cobertures del sòl urbà i l'índex de vegetació de diferència (NDVI). L'àrea d'estudi seleccionada va ser la ciutat costanera de Monte Hermoso, localitzada al sud-oest de la província de Buenos Aires (Argentina). Per fer-ho, es van processar imatges satel·litàries LANDSAT 5 TM i 7 ETM + per al període 2008-2012 de manera estacional. Amb aquestes imatges es va calcular la TST i l'NDVI. Posteriorment, es van aplicar tècniques d'interpretació visual i es van fer sortides al camp per dissenyar un mapa de cobertures del sòl urbà. Sobre aquestes, es va analitzar la variació de la TST i l'NDVI mitjançant el traçat de quatre transsectes orientats en sentit latitudinal i longitudinal. Cadascuna d'aquestes cobertures va presentar un comportament particular dels paràmetres calculats. D'altra banda, es van observar resultats significatius de la relació TST-NDVI (amb α de 0,1 i 0,05), amb valors de R 2 , índexs de Pearson i Spearman més grans de 0,7. Finalment, es va evidenciar que el canvi en les cobertures del sòl, producte del creixement urbà, va modificar els valors estacional...

ABSTRACT. Community-based natural resource management (CBNRM) is a concept critical to managing social-ecological systems but whose implementation needs strengthening. Scenario planning is one approach that may offer benefits relevant to CBNRM but whose potential is not yet well understood. Therefore, we designed, trialed, and evaluated a scenario-planning method intended to support CBNRM in three cases, located in Colombia, Mexico, and Argentina. Implementing scenario planning was judged as worthwhile in all three cases, although aspects of it were challenging to facilitate. The benefits generated were relevant to strengthening CBNRM: encouraging the participation of local people and using their knowledge, enhanced consideration of and adaptation to future change, and supporting the development of systems thinking. Tracing exactly when and how these benefits arose was challenging, but two elements of the method seemed particularly useful. First, using a systematic approach to discuss how drivers of change may affect local social-ecological systems helped to foster systems thinking and identify connections between issues. Second, explicitly focusing on how to use and respond to scenarios helped identify specific practical activities, or "response options," that would support CBNRM despite the pressures of future change. Discussions about response options also highlighted the need for support by other actors, e.g., policy groups: this raised the question of when and how other actors and other sources of knowledge should be involved in scenario planning, so as to encourage their buy-in to actions identified by the process. We suggest that other CBNRM initiatives may benefit from adapting and applying scenario planning. However, these initiatives should be carefully monitored because further research is required to understand how and when scenario-planning methods may produce benefits, as well as their strengths and weaknesses versus other methods.

<p>La transformación del medio natural por la acción humana alcanza su máxima expresión en las ciudades, donde afecta en modo especial las condiciones climáticas. La climatología urbana ha adquirido relevancia como respuesta a los problemas ocasionados por el crecimiento urbano en nuestro planeta. Las estimaciones prevén que en los próximos años más del 60 % de la población habitará en ciudades. Entonces, es necesario comprobar si este incremento podría perjudicar a sus habitantes y su entorno. En este contexto, el objetivo principal de esta investigación fue estudiar el clima local y micro-local de la ciudad de Bahía Blanca (Argentina) y comparar los resultados con estudios previos. De esta forma se pudieron evaluar los efectos de la variabilidad climática, del aumento de la población, etc. en el clima local con la finalidad de diseñar una propuesta de manejo urbano sostenible. La ciudad está localizada en el sudoeste de la provincia de Buenos Aires en el partido homónimo (38º 35'S, 62º 13'W) (Figura 1). El trazado de su plano es en forma de damero interrumpido en ciertas ocasiones por la altura. Su temperatura media anual de 15,5 ºC y las precipitaciones medias anuales de 654 mm.</p>

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