In recent decades, changes in climate have caused impacts on natural and human systems on all continents and across the
oceans. Evidence of climate-change impacts is strongest and most comprehensive for natural systems. Some impacts on human systems have
also been attributed5 to climate change, with a major or minor contribution of climate change distinguishable from other influences. See
Figure SPM.2. Attribution of observed impacts in the WGII AR5 generally links responses of natural and human systems to observed climate
change, regardless of its cause.
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