Innovative Trend Analysis Methodology
Top Cited Papers
- 1 September 2012
- journal article
- Published by American Society of Civil Engineers (ASCE) in Journal of Hydrologic Engineering
- Vol. 17 (9), 1042-1046
- https://doi.org/10.1061/(asce)he.1943-5584.0000556
Abstract
Hydrometeorological time series include recent trends, especially over the past 30 years, as a result of climate change impact according to the Intergovernmental Panel on Climate Change (IPCC). Although there are commonly used trend identification techniques, such as Mann-Kendall (MK) and Spearman’s rho (SR) tests, their validity is possible under a set of restrictive assumptions, such as independent structure of the time series, normality of the distribution, and length of data. It is also not possible to calculate trend magnitude (slope) except through regression approach, which brings additional assumptions for the theoretical validation in practical applications. This paper presents a new methodology on the basis of subsection time series plots derived from a given time series on a Cartesian coordinate system. In such a plot, trend free time series subsections appear along the 45° straightline. Increasing (decreasing) trends occupy upper (lower) triangular areas of the square area defined by the variation domain of the variable concerned. The validity of this new approach is documented through a set of Monte Carlo simulations by taking into consideration independent and dependent processes. In the new approach, all the aforementioned assumptions in the MK and SR tests are avoided, and additionally it is possible to calculate trend magnitude from square area plots. The application of this methodology is given for a set of precipitation and runoff time series from different parts of the world.Keywords
This publication has 13 references indexed in Scilit:
- Regional Analysis of Trend and Step Changes Observed in Hydroclimatic Variables around the Colorado River BasinJournal of Hydrometeorology, 2008
- Changes in U.S. Streamflow and Western U.S. SnowpackJournal of Hydrologic Engineering, 2008
- A step increase in streamflow in the conterminous United StatesGeophysical Research Letters, 2002
- Heavy Precipitation and High Streamflow in the Contiguous United States: Trends in the Twentieth CenturyBulletin of the American Meteorological Society, 2001
- Trends in floods and low flows in the United States: impact of spatial correlationJournal of Hydrology, 2000
- Streamflow trends in the United StatesGeophysical Research Letters, 1999
- Hydro-Climatological Trends in the Continental United States, 1948-88Journal of Climate, 1994
- A Nonparametric Trend Test for Seasonal Data With Serial DependenceWater Resources Research, 1984
- Estimates of the Regression Coefficient Based on Kendall's TauJournal of the American Statistical Association, 1968
- Nonparametric Tests Against TrendEconometrica, 1945