What your expectations were regarding the imperviousness of 2020 compared to 2010 and for which areas? How do define an "anomaly"? Maybe add some screenshots to help others understand the issue(s) you are referring to. You need to add more information in your question and make it more specific.

Hello! Thank you for your reply! I am currently conducting a study on the change in impervious surface area from 2000 to 2010 and 2020, and while processing the data and analyzing the statistics, I found that the rate of change in impervious surface area from 2010 to 2020 is significantly larger in some countries, relative to the rate of change from 2000 to 2010, such as Lebanon (Figure 1), and some countries in the Americas (Figure 2, El Salvador), including China (Figure 3). After reviewing the data, I found that this did not fit well with some of the statistics. Then I compared the 2020 land cover data of these countries with outliers, for example, the Sea of Galilee in Israel was identified as cropland in the 2020 data (Figures 4 and 5), and after reviewing the information, the lake still exists, and for the impervious surface surface, the comparison between 2020 and 2010 in Lebanon added many patches of impervious surface surface (Figures 6 and 7),. So there are doubts about the accuracy of the data of Global Land Cover 30m 2020 version.

How about a direct link to the documentation for the dataset you are using, Global Land Cover 30m 2020