With half the decade gone, only 4 months contribute to the collapse, while 8 months do their best to resist and compensate:

January packs 10% more volume in the 2010s than in the late 1900s.
February packs 14% more volume in the 2010s than in the late 1900s.
March packs 18% more volume in the 2010s than in the late 1900s.
April has 75% lower net refreeze volume in the 2010s than in the late 1900s.
May melts 92% more volume in the 2010s than in the late 1900s.
June melts 37% more volume in the 2010s than in the late 1900s.
July melts 14% less volume in the 2010s than in the late 1900s.
August melts 20% less volume in the 2010s than in the late 1900s.
September has 36% lower net refreeze volume in the 2010s than in the late 1900s.
October packs 17% more volume in the 2010s than in the late 1900s.
November packs 25% more volume in the 2010s than in the late 1900s.
December packs 12% more volume in the 2010s than in the late 1900s.