Maria Laura Bettolli

Pastura natural de salto (Uruguay): relación con la variabilidad climática y análisis de contextos futuros de cambio climático

NATURAL PASTURE IN SALTO (URUGUAY): RELATIONSHIP WITH CLIMATE VARIABILITY AND ANALYSIS IN THE CONTEXT OF FUTURE CLIMATE CHANGE. This work aimed to evaluate the relationship between natural pasture yield and climate variability in the district of Salto (Uruguay), and to analyze the possible implications of future climate change. Daily and monthly data from Salto meteorological station for the period 1961-1990 were used together with experimental data of pasture yield for the period 1980-1994. Moreover, NCEP reanalyses of daily data as well as daily outputs from General Circulation Models HadCM3 and CSIRO-Mk2 were

Surface Circulation Types and Daily Maximum and Minimum Temperatures in Southern La Plata Basin

AbstractLa Plata basin is one of the most important agricultural and hydropower-producing regions in the world. Extreme climate events such as cold and heat waves and frost events have a significant socioeconomic impact. This work analyzes the influence of the surface circulation in southern South America on daily maximum temperature TMAX and daily minimum temperature TMIN in southern La Plata basin. A Z test for the comparison of mean values and a Kolmogorov–Smirnov test for the comparison of distributions of TMAX and TMIN associated with each circulation pattern were performed. Specific daily surface circulation types are found to contribute to TMAX and TMIN anomalies and to have a predominant occurrence in the development of the extreme temperature events in the region. The TMAX spatial response to the regional low-level circulation is more homogenous and extended than is the response of TMIN.

Climate Change Impacts on Atmospheric Circulation and Daily Precipitation in the Argentine Pampas Region

The relevant findings of the Intergovernmental Panel on Climate Change (IPCC, 2007) highlight the increment of the global mean temperature and the need to understand how this increment will affect the climate variability and change of the regional environment. The changes in the climate are a consequence of both internal variability of the climate system and external factors, the latter being both natural and anthropogenic. The Fourth Assessment Report of IPCC describes the scientific progresses that have been achieved by researchers in the understanding the observed changes of the climatic system, the processes involved, and the establishment of future climate change projections (IPCC, 2007). The number of studies that discuss this problematic have increased considerable during the last years. However, there are many issues that need further investigation, in particular for developing countries. Extreme climate anomalies have a negative impact on the population and economy of the affected regions. The climate has a fundamental role for regions where the economy is based on agriculture. The process of growing crops can be seriously affected by extreme temperatures, and the precipitation can be a limiting factor which conditions the success or failure of the production. The region of interest in this study is the Pampas region, which comprises the most productive agricultural lands of Argentina. The most important grains of the country, like soybean, corn, wheat and sunflower are grown in this region. Together with their byproducts, these crops promote the social and productive system of the region, and are one of the principal sources of fiscal incomes. In the campaign of 2008/09, more than 24 million hectares, compared to of the country’s total of 28 million cultivated hectares of these grains, corresponded to the Pampas region (http://www.sagpya.mecon.gov.ar/). This region, located in the center east of Argentina, southeastern South America, have an extension of more than 600.000 km2. Since the grains are cultivated extensively without artificial irrigation, the precipitation is one of the climatic variables of main influence for the production, and is also a condition for the management of the crops. Therefore, the spatial and temporal distributions of the precipitation in the region, and its surplus or deficit, are of extreme importance for the successful harvests.