New and longer-term observations, and more extensive analyses on existing data reveal that impacts of recent changes in climate on natural systems, human and managed systems occur on all continents and across the oceans. This paper summarizes the recent findings from Working Group II contribution to the IPCC Fifth Assessment Report on the detection and attribution of observed changes, including assessment of the different types of impacted systems and progress of detection and attribution methods. And research and knowledge gap requiring more concerns are also presented in this paper.