Petit test, Double mass curve technique, Mann Kendal Rank Test etc...which is more hydrologically significant technique for change point detection. Please help me.
Different approaches have been found to be effective for identifying different types of changes so the answer will partly depend on the nature of changes that you suspect may be an issue for your data set and the type of changes that exist in the data set. Hence, applying many of the techniques suggested so far will be useful to help learn more about your data. One additional technique to consider is Bayesian Change Point Analysis, which is available through the BCP package in R. For any changes that are found, it is important to examine the metadata for your time series to look for any changes in measurement protocols or equipment that may explain the changes as well as any known physical changes that could explain the change (i.e., a forest fire on a watershed can result in changes to the streamflow time series).
I think in order to make robust conclusion, you had better use two different methods. For example, Double mass curve and Mann Kendal Rank Test. Please refer to this paper.
Wei, X., and M. Zhang (2010), Quantifying streamflow change caused by forest disturbance at a large spatial scale: A single watershed study, Water Resour. Res., 46, W12525, doi:10.1029/2010WR009250.
- Comparison with Double mass curves if you have more than two stations in order to verify the quality of the data and also if the change is natural and not do to biases in the measurements
- Petit test as suggested by others, it detect only one change point
- The segmentation procedure of Hubert which helps to detect more than one change point
Hubert P. (2000). The segmentation procedure as a tool for discrete modeling of hydrometeorological regimes. Stochastic Environmental Research and Risk Assessment 14(4)–(5):297–304.
I think it is better to use Double mass curve which is used to check the consistency of many kinds of hydrologic data bycomparing data for a single station with that of a pattern composed of the data from several other stations in the area.
Different approaches have been found to be effective for identifying different types of changes so the answer will partly depend on the nature of changes that you suspect may be an issue for your data set and the type of changes that exist in the data set. Hence, applying many of the techniques suggested so far will be useful to help learn more about your data. One additional technique to consider is Bayesian Change Point Analysis, which is available through the BCP package in R. For any changes that are found, it is important to examine the metadata for your time series to look for any changes in measurement protocols or equipment that may explain the changes as well as any known physical changes that could explain the change (i.e., a forest fire on a watershed can result in changes to the streamflow time series).