Global warming. Why did our climate heat up so much before the Little Ice Age?

"However, Jaworowski's views are rejected by the scientific community. Increases in CO2 and CH4 concentrations in the Vostok core are similar for the last two glacial-interglacial transitions, even though only the most recent transition is located in the brittle zone. Such evidence argues that the atmospheric trace-gas signal is not strongly affected by the presence of the brittle zone. [1] Similarly Hans Oeschger [2] states that "...Some of (Jaworowski's) statements are drastically wrong from the physical point of view"."