什么是气候“临界点”（tipping point），举两个例子。
What is a climate 'tipping point'? Give two examples.
临界点指系统被推过阈值后发生不可逆或自持的突变。例如格陵兰冰盖不可逆消融、亚马孙雨林向稀树草原转变——一旦越过，即便停止排放也难恢复。
A tipping point is a threshold beyond which a system shifts irreversibly or self-amplifies. Examples: irreversible Greenland ice-sheet loss and Amazon rainforest-to-savanna transition—once crossed, recovery is hard even if emissions stop.
难度 专业 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Lenton et al.
Lenton et al.
#临界点 #冰盖 #雨林
为什么 1.5–2°C 升温可能同时触发多个气候“临界点”？
Why might 1.5–2°C warming trigger several climate tipping points at once?
冰盖、AMOC、雨林、珊瑚等系统各有阈值且彼此关联（如暖化削弱 AMOC 又改变雨林降水），升温接近区间时多个子系统可能相继越过临界点，引发级联且难逆转的变化。
Ice sheets, AMOC, rainforests and reefs each have thresholds and are interlinked (warming weakens AMOC and shifts rainforest rains); near this range several may cross points in sequence, causing cascading, hard-to-reverse change.
难度 专业 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Nature / Science 综述
Nature; Science
#临界点 #级联 #不可逆
为什么科学家担心“级联”临界点？
Why are scientists concerned about 'cascading' tipping points?
一个区域触发可能通过大气环流、洋流或碳释放影响另一区域，形成连锁反应。例如南极冰损失削弱洋流，进而改变热带降雨，放大全局风险。
One region tipping can affect another via atmospheric circulation, ocean currents or carbon release, creating chains. E.g., Antarctic ice loss weakens currents, altering tropical rainfall and amplifying global risk.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
G. Tyler Miller,《Living in the Environment》Cengage 多版
G. T. Miller, Living in the Environment, Cengage Learning, various editions
独立核验依据 · Independent verification: 核验依据 2 OPENLIBRARY 标识 /works/OL66394W：Living in the environment
#临界点 #级联 #风险