Unit 2.0: Changes in natural systems are happening and will accelerate

2.1 Natural systems effects, such as temperature changes, precipitation patterns, extreme weather, sea level rise, ocean acidification, and biodiversity loss will become increasingly severe and frequent

2.2 Once a region passes a “tipping point,” it may be impossible to recover except over the very long-term

2.3 Changes in natural systems will vary widely by region based on natural geography