When a bomb is detonated below , feet but high enough that the fireball of the detonation does not actually touch the Earth's surface, it is considered an air blast. Both types of blasts yield different destructive outcomes to the surrounding areas. When a nuclear bomb is detonated close or on the ground, it produces radioactive fallout.
Upon explosion radioactive particles such as fission products, radiated soil and weapon waste are sent into varying levels of the atmosphere. Depending on the direction and power of the wind, radioactive fallout can travel extremely long distances. Unlike surface blasts, air blasts produce almost no local fallout upon detonation. It can be very intense, but its range is limited. For large nuclear weapons, the range of intense direct radiation is less than the range of lethal blast and thermal radiation effects.
However, in the case of smaller weapons, direct radiation may be the lethal effect with the greatest range. Direct radiation did substantial damage to the residents of Hiroshima and Nagasaki. Human response to ionizing radiation is subject to great scientific uncertainty and intense controversy.
It seems likely that even small doses of radiation do some harm. Fallout radiation is received from particles that are made radioactive by the effects of the explosion, and subsequently distributed at varying distances from the site of the blast. While any nuclear explosion in the atmosphere produces some fallout, the fallout is far greater if the burst is on the surface, or at least low enough for the firebalI to touch the ground.
The significant hazards come from particles scooped up from the ground and irradiated by the nuclear explosion. The radioactive particles that rise only a short distance those in the "stem" of the familiar mushroom cloud will fall back to earth within a matter of minutes, landing close to the center of the explosion.
Such particles are unlikely to cause many deaths, because they will fall in areas where most people have already been killed. However, the radioactivity will complicate efforts at rescue or eventual reconstruction.
The radioactive particles that rise higher will be carried some distance by the wind before returning to Earth, and hence the area and intensity of the fallout is strongly influenced by local weather conditions. Much of the material is simply blown downwind in a long plume. Rainfall also can have a significant influence on the ways in which radiation from smaller weapons is deposited, since rain will carry contaminated particles to the ground. The areas receiving such contaminated rainfall would become "hot spots," with greater radiation intensity than their surroundings.
Ground Zero The term "ground zero" refers to the point on the earth's surface immediately below or above the point of detonation. Blast Effects Most damage comes from the explosive blast. Thermal Radiation Effects Approximately 35 percent of the energy from a nuclear explosion is an intense burst of thermal radiation, i. Direct Nuclear Radiation Effects Direct radiation occurs at the time of the explosion. Those in underground shelters who survive the initial heat flash will die as all the oxygen is sucked out of the atmosphere.
Outside the area of total destruction there will be a gradually increasing percentage of immediate survivors. However most of these will suffer from fatal burns, will be blinded, bleeding and suffering massive internal injuries. Survivors will be affected within a matter of days by radioactive fall-out. Radiation-induced cancers will affect many, often over twenty years later.
Nuclear weapons cause severe damage to the climate and environment on a scale incomparable to any other weapon: the Red Cross estimates that a billion people around the world could face starvation as a result of nuclear war. Taking into account the effects a nuclear bomb would have, it is no surprise that CND campaigns against nuclear weapons.
They are immoral and expensive weapons of mass destruction, which have no military or strategic function in the face of 21st century threats. Your support goes a long way! Get the latest updates on our campaign. Email address Sign up.
0コメント