ANALYSIS OF METEOROLOGICAL STATIONS SITUATION ON URBAN, SEMIURBAN OR NONURBAN AREAS IN BRAZIL
ISBN 978-85-88783-11-9
Authors
1Nascimento, D.; 2Brito, B.
1PONTIFÍCIA UNIVERSIDADE CATÓLICA DE GOIÁS Email: diego.tarley@gmail.com
2PONTIFÍCIA UNIVERSIDADE CATÓLICA DE GOIÁS Email: brenda.12leg@hotmail.com
Abstract
Even when dealing with direct measurements, data records by meteorological stations have several problems, such as: 1) the quality of records that depend on the type of material used in stations; 2) poor and uneven density of the network of stations; 3) errors in readings caused by poor choice of location; 4) defects which instruments can present and result in failures or anomalous data datasets; 5) changes of equipment or even the place where the weather station is located and; 6) changes in coverage and land use where the instruments are located. In time of discussion about global climate change, little attention has been given to the conditions of cover and land use at the site and the surrounding meteorological stations. Considering the growth of cities, many stations formerly located in rural areas, are currently incorporated in urban areas. In this sense, the present work aims to analyze the situation of the meteorological stations in urban, semi-urban and non-urban areas in Brazil, in order to ascertain that these are incorporated into the urban centers and, in addition, give issues as to the influences of urbanization in the data record. For this propose, conventional and automatic meteorological stations of the official network of the National Institute of Meteorology (INMET) were intercepted by image night lights stabilized on the surface (stable lights) recorded at Operational Linescan System (OLS) aboard the Defense Meteorological Satellite Program (DMPS ). The image of night lights for the year 2012, with a spatial resolution of 1 km was compiled. The digital value for the pixels classified has on urban, non-urban or semiurban by natural breaking from histogram. Of the total of 710 meteorological stations of the INMET network, 342 are located in urban areas (52.5%), 198 in semi-urban areas (26.8%) and 170 in non-urban areas (20.7%). However, that amount of meteorological stations INMET, 237 are conventional stations, in which the recorded data is read and annotated by experts and sent to the center by a collector means any communication, and 473 are based on automatic stations, consisting of unit central memory (data logger) that makes the record and make them available to the center automatically. This division (conventional VS automatic) there is a considerable difference in the proportion between stations located in urban, semi-urban or non-urbanized areas. Among the 237 conventional stations, 155 are located in urban areas (65.4%), 56 in semi-urban (23.6%) and 26 in non-urban areas (11%). Therefore, 89% of these stations are located in areas of influence of urbanization. In turn, the amount of automatic stations (473), 187 are located in urban areas (39.5%), 142 in semi-urban (30%) and in non-urban areas 144 (30.5%) - indicating a homogeneous distribution over these three conditions and land use. In this work, it is seen that most of the INMET network meteorological stations are located in urban or semi-urban areas, which suggests that the meteorological data currently recorded are suffering the influence of urbanized areas. This fact can explain the variations or changes in the time series of data records, particularly of the air temperature. Since the replacement of natural vegetation to coverage and land use, associated with the heat generated by buildings and anthropogenic activities, changes in atmospheric composition and changes in the speed and flow of the winds, promotes the modification of the energy balance in the urban atmosphere - resulting in climate change at the local scale of cities, that is, the urban climate.
Keywords
Meteorological; Station; Situation