Trend analysis of an historical series of flow and precipitation using a non-parametric statistical test

  • Eduardo Morgan Uliana Universidade Federal de Mato Grosso
  • Demetrius David da Silva Universidade Federal de Viçosa
  • Estevão Morgan Uliana Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo
  • Beatriz Silveira Rodrigues Universidade Federal de Viçosa
  • Lucas de Paula Corrêdo Universidade Federal de Viçosa
Keywords: average flow, Pettitt test, rain, stationarity, time series

Abstract

Detecting trends in flow and precipitation series has great importance for the management of water resources and can be accomplished using statistic non-parametric tests. This work evaluated the significance of trends in flow and temporal series of precipitation as well as monthly and annual precipitation trends using Pettitt’s test. The study used historical series of flow and precipitation corresponding to the period of 1939 to 2005, recorded at stations 02041003 and 57450000 of the hydro-meteorological network of Water National Agency (ANA), located in the municipality of Alegre-ES. Using the Pettitt test, it was possible to identify a change in the trend of October average flow since the year 1963. The average for this month increased 34.2% since 1963. However, the rainfall series had a positive trend in August and September since the years 1967 and 1964, respectively. The increase in the October average flow may be a consequence of an increase in rainfalls in August and September; this requires further studies which may consider the influence of climate and anthropic factors in this hydrologic cycle component. Based on the results of the study, it was concluded that the Pettitt test performed satisfactorily in detecting trends in the historic series of flow and precipitation.

Author Biographies

Eduardo Morgan Uliana, Universidade Federal de Mato Grosso
Professor - Instituto de Ciências Agrárias e Ambientais - Universidade Federal de Mato Grosso (UFMT) - Campus Sinop Mestre em Produção Vegetal (UFES); Doutorando em Engenharia Agrícola (UFV)
Demetrius David da Silva, Universidade Federal de Viçosa
Doutor em Engenharia Agrícola - Professor - Departamento de Engenharia Agrícola - Universidade Federal de Viçosa (UFV)
Estevão Morgan Uliana, Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo
Graduando em Agronomia
Beatriz Silveira Rodrigues, Universidade Federal de Viçosa
Graduanda em Engenharia Ambiental - Bolsista de Iniciação Científica da FAPEMIG
Lucas de Paula Corrêdo, Universidade Federal de Viçosa
Graduando em Engenharia Agrícola e Ambiental - Bolsista de Iniciação Científica do CNPq
Published
08/12/2014
Section
Papers