translation.en: We know from ice core research that the transition from these cold conditions to warm conditions wasn't smooth, as you might predict from the slow increase in solar radiation.
translation.zh: 对冰芯的研究告诉我们， 从寒冷气候到温暖气候的转变 并不是非常平缓的， 你们可以通过太阳辐射的 缓慢增加中推测出来。