Re the glacier model : You can make the 20th century melt bigger/smaller by moving the ELA (1961-1990) up and down, Ives should know this. He should use a value that gives in his view a sensible 1961-1990 global mass balance (this is the rate of change of volume over that period). I am not sure what value he is using.
Philadelphia Warmed Four Degrees From 1830 To 1930
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