IMPACT OF CLIMATE CHANGE ON THE SUGAR CANE IRRIGATION WATER DEMAND IN THE GRAMAME RIVER WATERSHED | IMPACTO DAS MUDANÇAS CLIMÁTICAS NA DEMANDA DE ÁGUA PARA IRRIGAÇÃO DA CANA-DE-AÇÚCAR NA BACIA HIDROGRÁFICA DO RIO GRAMAME

Inglés. Climate change is a recurring theme as it impacts various sectors of society, including water resources, reflecting directly on human beings' activities. In this context, the objective of this study was to assess the impacts produced by climate change on the sugarcane water demands for irrigation in four municipalities within the Gramame River watershed. For this, the irrigation water demand was estimated from the calculation of the evapotranspiration of the sugarcane culture. The temperature data used in these estimates were obtained from the projections of three Regional Circulation Models: ICHEC-EC-EARTH-RCA4, MPI-ESM-LR-RCA4, and MPI-ESM-LR-REMO2009 taken from the Coordinated Regional Climate Downscaling (CORDEX). These demands were estimated for two intervals of years (2006-2037 and 2038-2069) and for two greenhouse gas emission scenarios, RCP 4.5 and RCP 8.5. The patterns of the temperature projections of the three models were evaluated and corrected in order to reduce uncertainties. The results indicate that the MPI-ESM-LR-REMO2009 model was the one that best represented the temperature in the current climate (1961-2005). Furthermore, the increase in temperature due to climate change affects irrigation water demand in the near future (2006-2037) with slight effects, and in the distant future (2038-2069) with stronger impacts.

Portugués. IMPACTO DAS MUDANÇAS CLIMÁTICAS NA DEMANDA DE ÁGUA PARA IRRIGAÇÃO DA CANA-DE-AÇÚCAR NA BACIA HIDROGRÁFICA DO RIO GRAMAME     YASMIM CRISTINA LEIROS MEIRA1 E RAFAEL CARNEIRO DE SOUZA BARROS2   1 Departamento de Engenharia Civil e Ambiental, Universidade Federal da Paraíba, Cidade Universitária, s/n, Conj. Pres. Castelo Branco III,58051-900, João Pessoa, Paraíba, Brasil, yasmimleiros@gmail.com. 2 Departamento de Engenharia Civil e Ambiental, Universidade Federal da Paraíba, Cidade Universitária, s/n, Conj. Pres. Castelo Branco III,58051-900, João Pessoa, Paraíba, Brasil, rafaelhc3@gmail.com.     1 RESUMO   As mudanças climáticas podem impactar variáveis climatológicas relacionadas com o processo de evapotranspiração das plantas e consequentemente, a demanda de água para irrigação das culturas. Este estudo busca avaliar os impactos gerados pelas mudanças climáticas nas demandas de água para irrigação da cana-de-açúcar em quatro municípios inseridos na bacia hidrográfica do Rio Gramame. Para isso, a demanda de água para irrigação foi estimada a partir do cálculo da evapotranspiração da cultura da cana-de-açúcar. Os dados de temperatura utilizados nessas estimativas foram obtidos das projeções de três Modelos de Circulação Regional: ICHEC-EC-EARTH-RCA4, MPI-ESM-LR-RCA4 e MPI-ESM-LR-REMO2009, retirados do Coordinated Regional Climate Downscaling (CORDEX). Essas demandas foram estimadas para dois intervalos de anos (2006-2037 e 2038-2069) e para dois cenários de emissão de Gases do Efeito Estufa, RCP 4.5 e RCP 8.5. Os padrões das projeções de temperatura dos três modelos foram avaliados e corrigidas afim de reduzir as incertezas. Os resultados indicam que o modelo MPI-ESM-LR-REMO2009 foi o que melhor representou a temperatura no clima atual (1961-2005), e que a demanda de água para irrigação será impactada levemente pelo aumento da temperatura decorrente da mudança climática no futuro próximo (2006-2037) e de forma mais significativa no futuro distante (2038-2069).   Palavras-chave: modelos de circulação regional, evapotranspiração, temperatura.     MEIRA, Y.C.L.; BARROS, R.C. DE S. IMPACT OF CLIMATE CHANGE ON THE SUGARCANE IRRIGATION WATER DEMAND IN THE GRAMAME RIVER BASIN     2 ABSTRACT   Climate change is a recurring theme as it impacts various sectors of society, including water resources, reflecting directly on human beings' activities. In this context, the objective of this study was to assess the impacts produced by climate change on the sugarcane water demands for irrigation in four municipalities within the Gramame River Basin. For this, the irrigation water demand was estimated from the calculation of the evapotranspiration of the sugarcane culture. The temperature data used in these estimates were obtained from the projections of three Regional Circulation Models: ICHEC-EC-EARTH-RCA4, MPI-ESM-LR-RCA4, and MPI-ESM-LR-REMO2009 taken from the Coordinated Regional Climate Downscaling (CORDEX). These demands were estimated for two intervals of years (2006-2037 and 2038-2069) and for two greenhouse gas emission scenarios, RCP 4.5 and RCP 8.5. The patterns of the temperature projections of the three models were evaluated and corrected in order to reduce uncertainties. The results indicate that the MPI-ESM-LR-REMO2009 model was the one that best represented the temperature in the current climate (1961-2005). Furthermore, the increase in temperature due to climate change affects irrigation water demand in the near future (2006-2037) with slight effects, and in the distant future (2038-2069) with stronger impacts.   Keywords: regional circulation models, evapotranspiration, temperature.