第一章：为什么我们要回望一万年？

你上周的体育课因为高温红色预警取消，抱着篮球回教室时刷到推送：南方大江水位跌到近50年最低，渔民在干裂河床捡田螺，北方山区五月飘雪，刚开的樱花被打落一地。爷爷奶奶总说他们小时候冬天河面能滑冰，现在的雪落地就化；课本里写的“四季分明”好像越来越远：春天倒春寒冻得穿棉袄，秋天热到全天开空调，夏天暴雨淹地下车库，冬天干旱得连雾霾都少见。你有没有觉得，天气好像越来越不听话了？

其实不是天气不听话，是地球的气候从来就不是一成不变的。我们以为“夏天热冬天冷”是理所当然的规则，就像你以为太阳每天从东边升起是永恒真理——但在地球46亿年的历史里，这两件事都只是短短一万年里的“特殊优惠”。

如果把地球46亿年的历史压缩成24小时，每一秒就代表53333年：$4600000000 \div (24 \times 60 \times 60) \approx 53333$ 年/秒。你昨天刷了2小时短视频，在地球历史上连0.00000001秒都不到，快到你眨个眼这段时间就从宇宙里消失了。但接下来我们要讲的这一万年，刚好是这24小时里的最后0.22秒——就是你凑到钟表前看秒针走完一整圈，最后那0.22秒连“咔哒”一声都还没响完的时间。

If we compress Earth's 4.6-billion-year history into 24 hours, each second represents 53,333 years. The 2 hours you spent scrolling short videos yesterday is less than 0.00000001 seconds in Earth's history, so fast that this time disappears from the universe before you can blink. But the next 10,000 years we are going to talk about is exactly the last 0.22 seconds in these 24 hours — it is the last 0.22 seconds when you lean close to the clock and watch the second hand finish a full circle, even the "click" sound has not finished yet.

就在这短短的一万年里，人类文明从无到有，从非洲的洞穴走到了火星表面：你吃的米饭、小麦是1万年前先民在野外偶然驯化的；你课本里学的古埃及金字塔是5000年前建的，也就是这24小时的0.09秒；中国的长城最早修建于2000多年前，是0.04秒；你玩的电子游戏是100年前发明的，只有0.0019秒；你刚才上的体育课，是0.00000002秒之前的事。这一万年足够人类从靠打猎为生进化到能发射探测器去别的星球，但在地球眼里，连一眨眼都算不上。

Just in this short 10,000 years, human civilization has grown from nothing to something, from caves in Africa to the surface of Mars: the rice and wheat you eat were accidentally domesticated by ancestors 10,000 years ago in the wild; the ancient Egyptian pyramids you learned in textbooks were built 5,000 years ago, which is 0.09 seconds in these 24 hours; the earliest construction of the Great Wall of China was more than 2,000 years ago, which is 0.04 seconds; the video games you play were invented 100 years ago, only 0.0019 seconds; the PE class you just had was 0.00000002 seconds ago. These 10,000 years are enough for humans to evolve from living by hunting to being able to launch probes to other planets, but in the eyes of the Earth, it is not even a blink of an eye.

一、被我们忽略的“气候稳定”错觉

我们总以为气候稳定是理所当然的：春天该开花就开花，秋天该落叶就落叶，夏天最热也就三十七八度，冬天最冷也就零下十几度，哪怕有极端天气也是小概率事件，影响不了生活。但科学家从格陵兰和南极的冰芯里提取的气泡样本告诉我们：这种“稳定”，其实是地球46亿年历史里极其罕见的“幸运时刻”。

We always think that climate stability is a matter of course: flowers bloom in spring, leaves fall in autumn, the hottest temperature in summer is only about 37 or 38 degrees Celsius, and the coldest temperature in winter is only about minus ten degrees Celsius. Even if there is extreme weather, it is a small probability event and will not affect life. But the bubble samples scientists extracted from ice cores in Greenland and Antarctica tell us: this "stability" is actually an extremely rare "lucky moment" in Earth's 4.6-billion-year history.

> 🌍 电子版侧边栏：小知识：冰芯是怎么当“温度计”的？ > 冰层里封存了一万年前的空气、灰尘甚至火山灰，科学家通过测量冰中氧同位素的比例就能知道当时的温度：氧-16比氧-18更轻，温度越高，蒸发到冰里的氧-18比例就越高，精度能到0.1℃，是地球天然的“气候记录仪”。 > 📎 纸书边注：氧同位素测温法由丹麦科学家威拉尔·达格加德于1950年代发明，2000年获得诺贝尔化学奖。

地球的气候变化主要受三个因素影响：太阳辐射的变化、地球轨道参数的波动（米兰科维奇周期）、火山活动和温室气体浓度。在人类文明诞生之前的上一个间冰期（12.5万年前），全球平均温度在几百年里波动幅度能达到10℃，今天撒哈拉沙漠的位置当时是热带草原，欧洲被几千米厚的冰盖覆盖，海平面比现在低120米，你站在现在的上海海边，能一路走到日本，因为东海大陆架当时是平原。那时候还没有农业，没有城市，更没有国家，人类只能靠采集和狩猎勉强生存，一次温度骤降就能让一半的人口冻死饿死。

The climate change of the earth is mainly affected by three factors: the change of solar radiation, the fluctuation of earth's orbital parameters (Milankovitch cycle), volcanic activity and greenhouse gas concentration. In the last interglacial period before the birth of human civilization (125,000 years ago), the global average temperature fluctuated by up to 10°C in a few hundred years. The location of the Sahara Desert at that time was a tropical grassland, Europe was covered by ice caps several kilometers thick, and the sea level was 120 meters lower than it is now. If you stand on the coast of Shanghai now, you can walk all the way to Japan, because the East China Sea continental shelf was a plain at that time. At that time, there was no agriculture, no cities, and no countries. Humans could only survive by gathering and hunting. A sudden drop in temperature could kill half of the population from freezing and starvation.

而我们现在所处的“全新世（Holocene）”，刚好是过去12000年里地球轨道参数最稳定的时期，温度波动幅度只有2到3℃，刚好够人类驯化植物、发展农业、建立城市。你以为的“稳定的气候”，其实是地球给了人类文明的一个“新手保护期”，而这个保护期，马上就要到期了。

And the "Holocene" we are in now happens to be the most stable period of Earth's orbital parameters in the past 12,000 years, with a temperature fluctuation of only 2 to 3°C, which is just enough for humans to domesticate plants, develop agriculture, and build cities. The "stable climate" you think is actually a "novice protection period" that the Earth gave to human civilization, and this protection period is about to expire.

过去一万年的温度，从来就没“稳”过

很多人觉得，过去一万年的气候都是差不多的，温度上下浮动也就零点几度，根本影响不了什么。但你把过去一万年的温度变化曲线拉出来看，会发现每一次上下波动，哪怕只有1℃，都足以改变整个文明的走向。

Many people think that the climate in the past 10,000 years was about the same, and the temperature fluctuated up and down by only a few tenths of a degree, which did not affect anything at all. But if you pull out the temperature change curve of the past 10,000 years, you will find that every fluctuation, even if it is only 1°C, is enough to change the direction of the whole civilization.

```mermaid linechart title 过去一万年全球平均温度变化（相对1950-1980年平均值，单位：℃） x-axis 距今年数（万年） 1.2 1.0 0.8 0.6 0.4 0.2 0 y-axis 温度异常 -4 -2 0 2 4 line 温度 -3.5 -2.2 -0.8 1.2 0.2 -0.8 1.1 ```

这张图是科学家从冰芯、树轮、湖泊沉积物里整理出来的过去一万年温度变化曲线，你能看到几个明显的波动节点： 1. 全新世大暖期（8000-5000年前）：温度比现在高1-2℃，全球降雨量充足，中国的

你上周的体育课因为高温红色预警取消，抱着篮球回教室时刷到推送：南方大江水位跌到近50年最低，渔民在干裂河床捡田螺，北方山区五月飘雪，刚开的樱花被打落一地。爷爷奶奶总说他们小时候冬天河面能滑冰，现在的雪落地就化；课本里写的“四季分明”好像越来越远：春天倒春寒冻得穿棉袄，秋天热到全天开空调，夏天暴雨淹地下车库，冬天干旱得连雾霾都少见。你有没有觉得，天气好像越来越不听话了？

其实不是天气不听话，是地球的气候从来就不是一成不变的。我们以为“夏天热冬天冷”是理所当然的规则，就像你以为太阳每天从东边升起是永恒真理——但在地球46亿年的历史里，这两件事都只是短短一万年里的“特殊优惠”。

如果把地球46亿年的历史压缩成24小时，每一秒就代表53333年：$4600000000 \div (24 \times 60 \times 60) \approx 53333$ 年/秒。你昨天刷了2小时短视频，在地球历史上连0.00000001秒都不到，快到你眨个眼这段时间就从宇宙里消失了。但接下来我们要讲的这一万年，刚好是这24小时里的最后0.22秒——就是你凑到钟表前看秒针走完一整圈，最后那0.22秒连“咔哒”一声都还没响完的时间。

If we compress Earth's 4.6-billion-year history into 24 hours, each second represents 53,333 years. The 2 hours you spent scrolling short videos yesterday is less than 0.00000001 seconds in Earth's history, so fast that this time disappears from the universe before you can blink. But the next 10,000 years we are going to talk about is exactly the last 0.22 seconds in these 24 hours — it is the last 0.22 seconds when you lean close to the clock and watch the second hand finish a full circle, even the "click" sound has not finished yet.

就在这短短的一万年里，人类文明从无到有，从非洲的洞穴走到了火星表面：你吃的米饭、小麦是1万年前先民在野外偶然驯化的；你课本里学的古埃及金字塔是5000年前建的，也就是这24小时的0.09秒；中国的长城最早修建于2000多年前，是0.04秒；你玩的电子游戏是100年前发明的，只有0.0019秒；你刚才上的体育课，是0.00000002秒之前的事。这一万年足够人类从靠打猎为生进化到能发射探测器去别的星球，但在地球眼里，连一眨眼都算不上。

Just in this short 10,000 years, human civilization has grown from nothing to something, from caves in Africa to the surface of Mars: the rice and wheat you eat were accidentally domesticated by ancestors 10,000 years ago in the wild; the ancient Egyptian pyramids you learned in textbooks were built 5,000 years ago, which is 0.09 seconds in these 24 hours; the earliest construction of the Great Wall of China was more than 2,000 years ago, which is 0.04 seconds; the video games you play were invented 100 years ago, only 0.0019 seconds; the PE class you just had was 0.00000002 seconds ago. These 10,000 years are enough for humans to evolve from living by hunting to being able to launch probes to other planets, but in the eyes of the Earth, it is not even a blink of an eye.

一、被我们忽略的“气候稳定”错觉

The Illusion of "Climate Stability" We Take for Granted

我们总以为气候稳定是理所当然的：春天该开花就开花，秋天该落叶就落叶，夏天最热也就三十七八度，冬天最冷也就零下十几度，哪怕有极端天气也是小概率事件，影响不了生活。但科学家从格陵兰和南极的冰芯里提取的气泡样本告诉我们：这种“稳定”，其实是地球46亿年历史里极其罕见的“幸运时刻”。

We always think that climate stability is a matter of course: flowers bloom in spring, leaves fall in autumn, the hottest temperature in summer is only about 37 or 38 degrees Celsius, and the coldest temper