  Climate change is one of the key topics in climate science. However, previous
research has predominantly concentrated on changes in mean values, and few
research examines changes in Probability Distribution Function (PDF). In this
study, a novel method called Wasserstein Stability Analysis (WSA) is developed
to identify PDF changes, especially the extreme event shift and non-linear
physical value constraint variation in climate change. WSA is applied to
21st-century warming slowdown period and is compared with traditional
mean-value trend analysis. The result indicates that despite no significant
trend, the central-eastern Pacific experienced a decline in hot extremes and an
increase in cold extremes, indicating a La Nina-like temperature shift. Further
analysis at two Arctic locations suggests sea ice severely restricts the hot
extremes of surface air temperature. This impact is diminishing as sea ice
melts. Overall, based on detecting PDF changes, WSA is a useful method for
re-discovering climate change.
