If the atomic bomb is used in the 3rd world war, what will happen to this world.

According to the Federation of American Scientists in 2019, the total number of atomic bombs in the world is 16 thousand. Of which 4,300 are in instant use condition. The rest can be activated in a very short time. The bombs used in Hiroshima and Nagasaki had a destructive power of 20,000 tons of TNT. At present, the average destruction capacity of stockpiled bombs is equivalent to 1.2 million tons of TNT. Of course, 70 times the power does not mean that they will destroy 80 times more area. In general, they have the potential to completely destroy a city 25 times larger than Hiroshima. However, the average intensity of destruction will be at least seven times that of Hiroshima. That is, if a bomb of this size is dropped in the center of London or New York City, they will be virtually wiped out. A single bombing of five populated cities, such as Shanghai, Peking, Karachi, Lagos and Istanbul, would kill at least 100 million people.

Today, more than half of the world's population (360 million) live in cities. 40 percent (146 crore) of them live in big cities. Given the military and economic importance, if bombs were dropped on large cities alone, about 1.5 billion people would die in the first 24 hours of the war. An estimated 1.5 billion people living in villages near cities will be seriously injured, with almost no access to medical care. It could kill another 500 million people. Aviation, telephone, internet, electricity, drinking water supply will be completely out of order. Roads, railways and shipping will collapse due to the destruction of fuel oil reserves. An estimated 500 million people will die within a year of the world's primary food crisis due to the destruction of a large portion of stored food. The use of technology in agriculture will come down to almost zero and declining food production will lead to global famine. As a result, the world's population will halve (350 million) in the next decade. Even if universities, laboratories and industrial establishments are destroyed, some part of the technology will still survive which could start a new civilization.

But the problem is elsewhere. Scientists estimate that the radiation from the 16,000 atomic bombs that will be spread over the Earth's surface could be enough to cause the extinction of fauna on Earth. About 2,000 atomic bombs have been tested so far, all underground or under the sea. The radiation emitted from these explosions could not reach the surface. Hiroshima, Nagasaki or Chernobyl have received enough environmental support to mitigate radioactivity. But the Earth does not seem to have the capacity to neutralize the amount of radioactivity that would spread to the earth's surface if such a large number of bombs exploded at once.

Part of the idea of ​​scientists is that radioactivity will not be limited to the area where the bomb will be dropped. Rather, it will spread to the atmosphere in the form of clouds and reach uninhabited areas and even distant Pacific island nations. All terrestrial animals will become extinct within the next 200 years. Only terrestrial plants and aquatic animals (especially marine animals) will survive. However, the idea of ​​a large part of scientists, there is no reason for the spread of radioactivity. And even if it did spread, it would take thousands or even millions of years for its response to be felt in the animal and plant world. As a result, even after an all-out nuclear war, half of the world's surviving people will be able to rebuild their civilization. If it is too much, maybe the journey will start from a century or a half back.