The argument for nuclear disarmament is rooted in the terrible effects and aftereffects of nuclear weapons, which were seen first hand in Hiroshima and Nagasaki. From the immediate thermal and shock effects to long term environmental damage, a nuclear detonation exacts terrible human costs. And weapons available today are many times more devastating than the ones detonated in Japan in 1945. Unlike the Hiroshima (15 kilotonnes) and Nagasaki (25 Kt) bombs, yields of the most powerful bombs developed during the Cold War can be measured in megatonnes (1 Mt = 1,000 Kt). The most powerful nuclear explosion ever recorded — the Russian Tsar Bomba in 1961 — had a yield of 50 Mt, more than 3,800 times that of the bomb detonated over Hiroshima. As the Nobel Committee recognises Japanese atom bomb survivors’ organisation Nihon Hidankyo for its “efforts to achieve a world free of nuclear weapons”, a look at what a nuclear detonation actually looks like. The blast A nuclear explosion itself will kill tens of millions of people (depending on where it takes place), and flatten entire cities. The most immediate effect of such an explosion would be a lethal burst of direct nuclear radiation (lasting under a second) whose effects can spread over many kilometres. But direct radiation is seldom experienced. This is because the thermal and shock effects of nuclear bombs have a larger radius of impact. Simply put, humans (and most things) will literally be vapourised, with the heart of the explosion registering temperatures hotter than the Sun’s million degree Celsius core. A massive fireball will form, which for a 1 Mt explosion will spread to almost two kilometres in diameter, emitting unbearable light and heat. This thermal flash may last many seconds, and lead to fires and severe burns to explosed flesh as far as 50 km from a large H-Bomb explosion. Thus, beyond people close to gound zero getting vapourised to death, a nuclear explosion will claim many more lives via deadly firestorms as buildings and other structure will spontaneously combust. Moreover, the blast wave from the explosion, responsible for most of the physical destruction, will lead to building collapses, objects flying all over the place, send people hurtling around, and cause internal bleeding. Moreover, fumes from raging fires will also kills ome people due to oxygen deprivation and carbon monoxide poisoning. Many people injured during the explosion will likely perish because the region’s health infrastructure would be completely destroyed. The fallout Unique to a nuclear explosion are its longterm aftereffects — the radioactive fallout. Nuclear reactions create additional radioactive material, that is, material made up of unstable atoms containing too much energy. When these atoms release energy, they are said to decay. This process involves the emission of various subatomic particles such as alpha particles, beta particles, neutrons, and gamma rays. This radiation is highly toxic for humans and other living beings. After a nuclear explosion, the immediate lethal nuclear radiation will likely last for weeks, and claim many more lives. But the actual fallout may linger for decades. Over the first 9 weeks of a nuclear explosion, it is estimated that roughly 10% of deaths will be due to the effects of radiation, with 90% deaths being due to thermal injuries or blast effects. However, the effects of radiation will manifest themselves in the form of various cancers and genetic damage over the coming years and generations. In fact, even very low levels of nuclear radiation can drastically increase incidence of cancers and certain other diseases, meaning that the effects of a nuclear explosion will go well beyond the blast radius itself. According to some estimates, roughly 2.4 million people worldwide will eventually die from cancers due to atmospheric nuclear tests conducted between 1945 and 1980. The environment and climate will also feel the effects of a nuclear explosion, especially if there is a global nuclear armageddon. Scientists do not rule out permanent changes to the planet’s climate and environment. A nuclear winter, a product of Earth being completely wrapped by the cloud from nuclear explosions, would lead to rapid global cooling, crop failures, and upend human civilisation and the economy.
