The line graph illustrates three of the major lakes covered by the highest percentage of surface ice between 2000 and 2020.
In general, the two lakes superior and Michigan are quite similar in trend, while lake Erie is significantly different from them. however, there is a common trend between observed between all of them, which is a sharp decline right after 2015.
firstly, lake superior has surface size of about 40% in 2000, with which a minor spike and a decrease in 2005 and 2010 is experienced, respectively, Which resulted in a dramatical spike up to 95% by 2015. Meanwhile, lake Michigan follow the quite stable trend starting at 30% in 2000 to about 25% in 2010, then a dramatical rise up to 80% till reaching 2015. Lastly, for lake Erie, the percentage remains quite constant while reaching 2015 at 90%.
Overall, It is quite interesting to note that, right after 2015 all of the three legs experience the major fail till the year 2020.
