Arctic sea ice extent refreeze has come 101% of the way since Summer Minimum per February 18th. The lowest extent year ever, 2016, by the same date, was at 96%.
Q: Where’s the data source for this plot?
A: Here: https://ads.nipr.ac.jp/vishop/#/extent
Q: How can anyone know if there is a full refreeze?
A: Easy. Use a computer. If you have e.g a 10 million km² extent melt, and then the refreeze is also 10 million km², then you have a full, or 100%, refreeze.
Q: Why would I even do that?
A: Let’s say you want to know how much ice refreezes compared to how much ice that melted away.