translation.en: So CO2, methane, and ice sheets were feedbacks that amplified global temperature change causing these ancient climate oscillations to be huge, even though the climate change was initiated by a very weak forcing.
translation.zh: 因此，二氧化碳、甲烷和冰盖 都是放大了 全球温度变化的反馈， 尽管气候变化最初是因小小的变化而起， 这些古老的气候变化指数 也会变得非常大。