Abstract: The Good Practice Guidance Paper (GPGP) presents four different methods, which encompasses existent different approaches to investigate the causation chain. Since 1990, the detection and attribution study of climate changes has undergone a refinement process in spatial scale of temperature rise (warming) from the global to half-hemispheric scale and from the continental to regional scale, and an expansion process in research topic from lands to oceans, and from the climate system to other related systems. The fingerprinting detection and attribution method of anthropogenic climate changes has been extensively applied in studies on spatiotemporal pattern changes of global/large scale hydrological cycle elements, such as latitudinal band average precipitation, extreme precipitation, specific humidity, lower tropospheric moisture content, and individually in the streamflow impacted by external forcings, natural runoff, snow pack and minimum temperature on a river basin scale. For the river basins recharged by precipitation and impacted by human activities, the detection and attribution studies of hydrological cycle elements mainly focus on effects of observed climatic elements and non-climatic variables on streamflow, without the emphasis on causation by the anthropogenic component of climate change. For this kind of approach, long term observed climatic and non-climatic data, advanced statistic technology and hydrological model with better physical basis are vital for the correct recognition of causation process. In the river basins with high qualified long term observed climate and non-climate data, where hydrological variables are sensitive to climate changes, the optimal fingerprinting method will be valuable in detection and attribution studies.

Key words: IPCC assesement report, climate change, hydrological cycle, detection and attribution