如果發生核戰會怎樣？：英語精讀講義

70 years ago the nuclear bombs dropped over Hiroshima and Nagasaki exploded 文化背景

70年前，投向廣島和長崎的核彈爆炸了

and to this day remain the only use of nuclear weapons for warfare. 片語搭配

而直到今天，這仍是核武器唯一一次被用於戰爭。

But with around 15,000 warheads remaining in the world, 用詞

但如今全球仍有約1.5萬枚核彈頭，

what happens if we have a nuclear war?

如果爆發核戰爭，會發生什麼事？

The impact of a single nuclear bomb depends on many factors like the weather, weapon design,

一枚核彈造成的影響取決於許多因素，例如天氣、武器設計、

geographical layout of where the bomb hits,

核彈命中地點的地理環境，

and if it explodes in the air or on the ground.

以及它是在空中還是地面爆炸。

Approximately 35% of the energy comes in the form of thermal radiation or heat. 講解

約35%的能量會以熱輻射，也就是熱能的形式釋放。

Since thermal radiation travels at approximately the speed of light,

由於熱輻射的傳播速度接近光速，

the flash of light and the heat comes several seconds before the blast wave.

強光和熱能會比爆炸衝擊波早幾秒抵達。

And this causes flash blindness to anyone looking, 用詞

這會讓所有直視它的人出現閃光失明，

a temporary blindness of a few minutes.

也就是持續幾分鐘的暫時性失明。

With a 1 megaton bomb, 用詞

以一枚100萬噸當量的核彈為例，

which is 80 times larger than the Hiroshima bomb,

它的威力是廣島原子彈的80倍，

but much smaller than many modern nuclear weapons,

但仍遠小於許多現代核武器，

those 21 km away would experience flash blindness on a clear day

在晴朗的白天，21公里外的人會出現閃光失明，

and even up to 85 km away on a clear night.

而在晴朗的夜晚，最遠85公里外的人也會如此。

Thermal radiation burns happen closer to the bomb with first-degree burns occurring around 11 km, 用詞

在離核彈更近的地方，熱輻射會造成燒傷：約11公里處會出現一度燒傷，

second-degree burns at 10 km,

10公里處是二度燒傷，

and third-degree burns destroying skin tissue at 8 km.

8公里處則是會破壞皮膚組織的三度燒傷。

Third-degree burns that cover over 24% of the body will likely be fatal without quick medical care.

如果三度燒傷覆蓋身體超過24%，沒有及時接受治療就很可能致命。

These distances are variable depending on the weather and what clothing you're wearing. 片語搭配

這些距離會因天氣和你所穿的衣物而異。

White clothing, for example, can reflect some of the energy

例如，白色衣物可以反射部分能量，

while darker clothes absorb it. 文法

深色衣物則會吸收能量。

At its center, the Hiroshima explosion was estimated to be 300,000 °C, 文法

據估計，廣島爆炸中心的溫度高達30萬°C，

which is over 300 times hotter than the temperature bodies are cremated at. 文法

比遺體火化時的溫度高出300多倍。

This intense heat reduces a body to its basic elements.

這種極端高溫會把人體分解成最基本的元素。

The radiation from the blast also behaves like sunlight,

爆炸產生的輻射也像陽光一樣傳播，

so objects cast shadows where the radiation doesn't directly hit. 片語搭配

因此在輻射沒有直接照射到的地方，物體會留下影子。

But most of the energy released in a nuclear explosion is in the blast,

但核爆釋放的大部分能量都形成了爆炸衝擊波，

which drives air away from the site of the explosion,

它會將空氣從爆炸地點猛烈推開，

creating a sudden change in air pressure that can crush objects or knock them down. 文法

造成氣壓瞬間改變，足以壓碎物體或將其掀倒。

If we use a 1 megaton bomb as an example again, 表達脈絡

再次以一枚100萬噸當量的核彈為例，

within a 6 km radius,

在半徑6公里內，

there would be an estimated 180 tons of force on the wall of every two-story building 文法

每棟兩層樓建築的牆面估計都要承受180噸的衝擊力，

with wind speeds of 255 km/h.

風速可達每小時255公里。

Within a 1 km radius,

在半徑1公里內，

the peak pressure is four times greater and wind speeds reach 756 km/h.

峰值壓力會增至4倍，風速達到每小時756公里。

The human body can endure this amount of pressure.

人體本身可以承受這麼大的壓力。

However, the winds would create fatal collisions with nearby objects,

然而，強風會將人吹去撞上附近物體，造成致命傷害，

so deaths would largely be from collapsed buildings.

所以死亡主要會由建築物倒塌造成。

All this at 1 megaton.

而這一切，還只是一枚100萬噸當量核彈的威力。

Compare that with the largest nuclear bomb ever detonated, 表達脈絡

再拿它和史上引爆過的最大核彈相比：

the 50 megaton Tsar Bomba dropped on an isolated island in Russia, 文化背景

那就是投在俄羅斯一座偏遠島嶼上的5,000萬噸當量「沙皇炸彈」，

and you're looking at 3,333 Hiroshima bombs combined. 慣用語

其威力相當於3,333枚廣島原子彈加在一起。

If you happen to survive all this, 文法

如果你碰巧在這一切中倖存下來，

now you have to worry about radiation.

接著還得擔心輻射。

Now, not all radiation is harmful. 文法

當然，並非所有輻射都有害。

We're exposed to different forms of radiation every day like our phones, 片語搭配

我們每天都會接觸不同形式的輻射，例如手機產生的輻射，

but ionizing radiation at the center of a nuclear bomb has enough energy to rip electrons from atoms. 講解

但核彈中心的游離輻射能量足以將電子從原子中剝離。

But the amount of radiation you encounter is greatly affected by whether you're outside or inside, 文法

不過，你接觸到的輻射量會因許多因素而大不相同，例如你在室外還是室內，

in a wooden structure or a cement structure, and so on.

身處木造結構還是水泥結構中，等等。

Exposure to 600 REM radiation has a 90% chance of creating fatal illness, 用詞

受到600 REM的輻射，有90%的機率會引發致命疾病，

while a dose of 450 REM is estimated to create a fatal dose within half of those affected.

而450 REM的輻射劑量，估計會讓一半受影響的人死亡。

But even those who recover still suffer long-term.

即使康復，倖存者仍會承受長期影響。

Molecular bonds and strands of DNA are broken,

分子鍵和DNA鏈會斷裂，

and while most repair, around a quarter don't, 文法

雖然大部分都能修復，但約有四分之一無法修復，

which can result in future genetic mutations and increased probability of cancer. 片語搭配

這可能導致日後出現基因突變，並提高罹癌機率。

Then there is the fallout. 講解

此外，還有放射性落塵。

When a bomb is detonated on or near the surface of the Earth,

當核彈在地表或地表附近引爆時，

the blast creates a crater and the material that used to be deposited in the crater

爆炸會炸出一個彈坑，原本位於彈坑範圍內的物質

is carried up into the air as vaporized dirt particles,

會化為汽化的塵土顆粒，被捲入空中，

forming the familiar mushroom cloud.

形成我們熟悉的蕈狀雲。

These particles become radioactive and eventually condense

這些顆粒會帶有放射性，最後凝結，

and come back down as fallout.

再以放射性落塵的形式落回地面。

Depending on wind conditions,

視風況而定，

radioactive fallout can travel for hundreds of miles.

放射性落塵可以飄到數百英里之外。

And though it can fall in the form of black rain,

雖然它有時會以黑雨的形式落下，

for the most part, you can't detect fallout with your senses. 片語搭配

但大多數時候，你無法透過感官察覺放射性落塵。

Luckily, fallout radiation decays fairly quickly,

幸運的是，落塵的放射性會相當快地衰減，

and within 2 weeks material will have declined to about 1% of its initial radiation level. 文法

兩週內，其輻射量就會降至初始水準的約1%。

But you would have to stay in a shelter until then.

但在那之前，你必須一直待在避難所裡。

So, what if a multi-bomb nuclear war broke out? 講解

那麼，如果爆發一場動用多枚核彈的核戰爭，會怎樣？

A recent study imagined what 100 detonated warheads,

最近一項研究設想了100枚核彈頭爆炸的情境，

the approximate size of a Hiroshima bomb,

每枚威力大約相當於一枚廣島原子彈，

would look like if India and Pakistan went to war.

藉此推演印度與巴基斯坦開戰會是什麼景象。

These two nations have relatively small stockpiles of weapons

這兩個國家的武器庫存相對較少，

compared to countries like the US, Russia, and China.

尤其是與美國、俄羅斯和中國等國相比。

However, this would still do huge damage. 片語搭配

儘管如此，破壞仍會極為嚴重。

After the nuclear exchange, 用詞

在核武交鋒之後，

5 megatons of black carbon would immediately enter the atmosphere,

500萬噸黑碳會立刻進入大氣層，

causing global temperatures to fall and receive 9% less rain annually.

導致全球氣溫下降，每年降雨量減少9%。

Though these changes sound small,

雖然這些變化聽起來不大，

they could be enough to trigger crop failures and famine. 文法

卻足以引發農作物歉收和飢荒。

A separate study estimated 2 billion people would starve in the wake of a 100 A-bomb war. 慣用語

另一項研究估計，一場動用100枚原子彈的戰爭過後，將有20億人挨餓。

So, what should you do?

那麼，你該怎麼辦？

We created a video called How to Survive a Nuclear War

我們製作了一支名為《如何在核戰爭中生存》的影片，

that looks into strategies for safety in the event of a nuclear bomb near you, 講解

其中探討了附近發生核爆時的安全應對策略，

which you can click on here to check out.

點這裡就可以觀看。

Don't forget to subscribe for more weekly science videos every Thursday

別忘了訂閱，每週四收看更多科學影片，

and click that bell to make sure you get notifications for our videos.

還要按一下鈴鐺，確保能收到我們的影片通知。

We'll see you next week.

我們下週見。