期刊名称:Cuadernos de Investigación Geográfica = Geographical Research Letters
印刷版ISSN:0211-6820
电子版ISSN:1697-9540
出版年度:2019
卷号:45
期号:1
页码:393-416
DOI:10.18172/cig.3707
出版社:Universidad de La Rioja
摘要:The south of Pampas (36° 32’-40° 44’ S; 63° 24’-60° 30’ W), 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.
关键词:Short-term climatic variability; climatic sub-regions; trends; structural changes; south of Pampas.