Apparently team climate fraud got tired of being accused of hiding the inconvenient pre-1979 Arctic sea ice data, which showed a sharp increase in sea ice during the 1970s.

1990 IPCC Report

So they simply replaced it with fake data which shows a decrease during the 1970s.

ice_minmax_n.png (1613×1148)

No surprise there. Making up fake data is standard operating procedure for climate alarmists.

h/t Climate Detective