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Spatial Modeling of Climatic Parameter Fluctuation Mapping Temperature Variation in the Bermejo Basin from 1901 to 2000
Martín de Zuviría
MaxSys Engineering GIS/RS Scientist. 176 Rideau St, Ottawa, ON K1N9P1, Canada.
Tel: (613)789-2606; Fax: (613) 789-0078. E-mail: mdezuviria@sympatico.ca
Osvaldo F. Canziani
Co-chair, IPCC Working Group II. Ave. R. Scalabrini Ortiz 1978, 1425 Buenos Aires, Argentina.
Tel/Fax: (54-11)4831-7864. E-mail: ocanz@ciudad.com.ar
Abstract
Understanding the spatial and temporary variations in climate within a zone, and their relationships with other factors, is important in activities related to climate change and the management of the natural resources, such as environmental planning, land-use planning, watershed management and territorial ordering. Even when these variations are sometimes reported in maps, the values represented there are presently often obtained by the straight application of subjective criteria, seldom supported or replaced by the systematic use of computerized techniques of spatial data analysis and modeling.
In this study, a method is presented for mapping and analyzing the temporary variations of climatic parameters linked to the global climate change. This method focuses on the use of geographic information systems (GIS) and is tested in producing temperature variation maps of the Bermejo river basin, in northwest Argentina.
To produce these maps, temperature and rainfall data of meteorological stations were first summarized for different periods from 1873 to 2000 to build up a tabular database, and a digital elevation model was produced from topographic data using GIS capabilities. Tabular and elevation data were then linked in a GIS environment to produce air temperature maps following the presented method, and maps showing temperature variations from 1901 to 2000 were derived. Ranges of air temperature most probably correlated with land-use suitability were selected, and two maps showing thermal zones were produced. These maps were crossed and a map showing the shift of the thermal zones was developed, illustrating the consequent spatial shift of land use and farming types agroclimatic suitability. Isopleths were derived from maps showing temperature and thermal zones variations, and these lines were plotted onto land-use and vegetation maps to allow the visual assessment of temperature variations within different land cover types. This led to the identification of areas most likely affected by temperature variations within different cartographic units. In addition, the original grid maps showing temperature variations were used to quantify the magnitude of these variations within each land cover type, to report them statistically and to relate these magnitudes to the degrees of the occurred impacts within each unit.
The geo-database developed during this mapping process, consisting of tables, formulae, maps and their relationships, is built up using dependency links among objects. Consequently, when input source maps, tables or formulae are improved, the dependent output maps and/or tables can be automatically recalculated. The geo-database will be also used for the development of scenarios to represent future trends of air temperature under different local and global conditions, and to locate and analyze the dynamic variation of other climatic parameters, contributing to the study of climate change and land use planning at different scales.
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