Comparison of rainfall forecast models in parana in the presence of a gold standard

Submitted by Rosangela Silva (rosangela.silva3@unioeste.br) on 2020-03-03T18:21:24Z No. of bitstreams: 2 MARCIO PAULO DE OLIVEIRA.pdf: 18106561 bytes, checksum: 8ed0167eca3f5516ccd489a4516d78fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2020-03-03T18:21:24Z (GMT). No. of bitstreams: 2 MARCIO PAULO DE OLIVEIRA.pdf: 18106561 bytes, checksum: 8ed0167eca3f5516ccd489a4516d78fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2019-12-18 The forecasts of agrometeorological variables are applied to guide several agricultural activities. The rainfall forecasts are important due to the impacts, which water excess or deficit can cause on the development of agricultural crops. The forecasts are performed by several national centers with parameterizations that can produce different forecasts for a certain agrometeorological variable in the same site. Thus, this trial aims at carrying out comparisons in the presence of a gold standard for georeferenced rainfall forecasts in some regions of Paran´a State - Brazil. The first research studied the state of Paran´a, from October to March of cropping years 2011/2012 to 2015/2016. The forecasts were clustered in fiveday periods for step 24-hour, and ten-day for step 240-hour, in which the data are from the Canadian Meteorological Center (CMC), European Center for Medium-Range Weather Forecasts (ECMWF), National Centers for Environmental Prediction (NCEP) and Center for Weather Forecasting and Climate Studies (CPTEC) according to the base Interactive Grand Global Ensemble (TIGGE). The measures gold standard were obtained from meteorological stations of the SIMEPAR Technological Institute. The results showed some variability when selecting the forecasting centers for the studied sites, mainly in mesoregions of Paran´a state. The Western Paran´a mesoregion area was studied in the second trial, from October to March of the soybean cropping years 2010/2011 to 2015/2016. The predictions of CMC, ECMWF, NCEP and CPTEC centers at the 240-hour were compared with the gold standard, which is obtained by mean values of observations from National Water Agency - Brazil (ANA) meteorological stations within a 0.36◦ radius of the centroid of the predicted site (pixel) clustered in ten-day periods. The agreements were obtained with normal distribution, and normality was achieved by Yeo-Johnson transformation with data divided into four ranges. The results indicated variability based on centers which were chosen in the mesoregion, according to the precipitation range. The third trial was based on the second paper data and the agreements were obtained using the three-parameter gamma distribution and the gamma difference distribution. The agreements with gamma distribution modelling ratified the variability of selecting centers in the Western Paran´a mesoregion for each range. As previso˜es de caracter´ısticas agrometeorol´ogicas s˜ao utilizadas para orientar diversas atividades agr´arias. A previs˜ao da precipita¸c˜ao pluviom´etrica destaca-se devido aos impactos que o excesso ou o d´eficit h´ıdrico pode causar no desenvolvimento de culturas agr´ıcolas. As previso˜es s˜ao realizadas por diversos centros nacionais que utilizam parametriza¸co˜es que podem produzir distintas previso˜es para certa vari´avel agrometeorolo´gica em uma mesma localiza¸c˜ao. Assim, o objetivo deste trabalho foi realizar compara¸co˜es na presen¸ca de um gold standard em previso˜es de precipita¸c˜ao pluviom´etrica georreferenciadas em regio˜es no estado do Paran´a - Brasil. No primeiro trabalho, a regi˜ao de estudo foi o estado do Paran´a, no per´ıodo de outubro a marc¸o dos anos-safra de 2011/2012 a 2015/2016. Foram comparadas as previso˜es no passo de 24 horas, agrupadas em quinqu´ıdios, e no passo de 240 horas que correspondem a decˆendios. Os dados utilizados neste estudo s˜ao dos centros Canadian Meteorological Center (CMC), European Center for Medium-Range Weather Forecasts (ECMWF), National Centers for Environmental Prediction (NCEP) e Centro de Previs˜ao de Tempo e Estudos Clim´aticos (CPTEC) da base Interactive Grand Global Ensemble (TIGGE). As medidas gold standard foram obtidas de esta¸co˜es meteorolo´gicas do Instituto Tecnol´ogico SIMEPAR. Os resultados mostraram variabilidade na sele¸c˜ao de centros de previs˜ao para as localiza¸co˜es em estudo, inclusive em mesorregio˜es do estado do Paran´a. No segundo trabalho, a ´area utilizada foi a mesorregi˜ao Oeste do Paran´a no per´ıodo de outubro a mar¸co dos anos-safra de soja de 2010/2011 a 2015/2016. As previs˜oes dos centros CMC, ECMWF, NCEP e CPTEC no passo 240 horas foram comparadas com o gold standard, obtido pelo valor m´edio de observa¸co˜es das esta¸co˜es da Agˆencia Nacional de ´Aguas (ANA) em um raio de 0,36◦ do centroide da localiza¸c˜ao prevista (pixel), e agrupadas em decˆendios. As concordˆancias foram obtidas com a distribui¸c˜ao normal e a normalidade foi alcan¸cada a partir da transforma¸c˜ao de Johnson, nos dados divididos em quatro classes. Segundo a classe de precipita¸c˜ao em estudo, os resultados indicaram variabilidade na escolha dos centros na mesorregi˜ao. As concordˆancias do terceiro trabalho foram obtidas com o uso da distribui¸c˜ao gama de trˆes parˆametros e da distribui¸c˜ao de diferen¸ca de gama. As concordˆancias com essa modelagem confirmaram a variabilidade da selec¸˜ao de centros na mesorregi˜ao Oeste do Paran´a para cada classe.