Nuclear Winter

The extreme events which have been discussed differ in their characteristic spatial scales of importance. Each event which causes wind-throw occurs on a smaller spatial scale than a pollution event, as recently seen by the very extensive scale of the Chernobyl fallout (Johnston, 1987). At an even greater scale, the projected extent of the nuclear winter will be global (Covey, 1987). Examples of this hierarchy of scales of events are shown in Table 1. 

For the first time in human history, the future of mankind is in our own hands. Onto the road leading to a sustainable and peaceful future, we ourselves have placed several "roadside bombs." We must safely pass these. We must avoid energy wars, the collapse of the global economy, creating a drastic change in the climate or bringing a nuclear winter. 

Turco R. P., Toon O. B., Ackerman T., Pollack J. B. and Sagan C., Nuclear Winter global consequences of multiple nuclear explosions. Science, 222, 1283-1292 (1983). 

Although various restrictions have been placed on carbon particulate emissions from different types of power plants, these particles can play a beneficial, as well as a detrimental, role in the overall plant process. The detrimental effects are well known. The presence of particulates in gas turbines can severely affect the lifetime of the blades soot particulates in diesel engines absorb carcinogenic materials, thereby posing a health hazard. It has even been postulated that, after a nuclear blast, the subsequent fires would create enormous amounts of soot whose dispersal into the atmosphere would absorb enough of the sun s radiation to create a nuclear winter on Earth. Nevertheless, particulates can be useful. In many industrial furnaces, for example, the presence of carbon particulates increases the radiative power of the flame, and thus can increase appreciably the heat transfer rates. 

Opponents of the nuclear winter theory argue that there are many problems with the hypothesized scenarios either because of the model s incorrect assumptions (e.g., the results would be right only if exactly the assumed amount of dust would enter the atmosphere, or because the model assumes uniformly distributed, constantly injected particles). Other critics of the nuclear winter scenario point out that the models used often to not include processes and/or feedback mechanisms that may moderate or mitigate the initial effects of nuclear blasts on the atmosphere (e.g., the moderating effects of the oceans). 

The nuclear winter scenario remains scientifically controversial because the exact level of atmospheric damage, along with the extent and duration of subsequent processes cannot be agreed upon with full confidence. 

Turco, R.P., O.B. Toon, T.P. Ackerman, J.B. Pollack, Carl Sagan, Nuclear Winter Global Consequences of Multiple Nuclear Explosions, Science, 222,4630 (1983). 

Weinberger, Casper. The Potential Effects of Nuclear War on the Qimate, Nuclear Winter, Joint Hearing before the Committee on Science and Technology and the Committee on Interior and Insular Affairs, U.S. House of Representatives. GPO 1985) 274-277. 

White Paper. Nuclear Winter Scientists in the Political Arena. Physics in Perspective. 3 1 (2001 ) 76-105. 

Nuclear Winter, terrorism, as well as the increased incidence of rural/urban wildfires as the public penetrates previously unsetded regions makes the situation urgent. 

Estimation of Risk. The estimation of risk contains uncertainties, based on the lack of specific data (such as exposure information) and/or the lack of understanding of the mechanism of toxic action of a compound. Between the extremes of acturial risk, which is based on enough information that "time has removed the uncertainty," such as the probability of death as cited in an insurance table, and theoretical risk, which is based on probabilistic calculations of events which have never actually occurred (e.g., nuclear "winter" (7)) lies a wide continuum into which most estimates of human health effects fall. In real-life situations, many assumptions are made in evaluating risk in order to make a conclusion, and these assumptions lead to uncertainties in the final result. These uncertainties should be understood as limitations to the best guess science can presently make. Although one response to this uncertainty, in the face of an outcome as fearsome as cancer, is to deny that there is a lack of certainty, the more reasonable response is to try to estimate the uncertainty, making it clear that any estimate is bracketed by these possible errors. 

Obtaining clinical candidates through in-licensing and acquisition has become so competitive, in fact, that in 2005 the median acquisition deal cost pharma companies 170 million, almost triple the 2004 price of 57 million. To the biotech industry, strapped for cash in the wake of the nuclear winter of 2002, this is a welcome relief, even if it means having to sell an innovative small company lock, stock, and barrel. 

Less efficient machines required two-thirds of a century to assemble a nation of the dead the nuclear death machine could manage it in half an hour. The nuclear death machine has become capable of creating not merely cities of the dead or nations of the dead but a world of the dead. (Even before detailed studies appeared of the potentially widespread disaster known as nuclear winter, the World Health Organization had estimated— in 1982—that a major nuclear war would kill half the population of the earth two billion people.) Therefore, Elliot deduces ... 

Harwell, Mark A. 1984. Nuclear Winter. Springer-Verlag. 

Powers, Thomas. 1984. Nuclear winter and nuclear strategy. Atlantic. Nov. 

It should also be understood that a profound perturbation of the earth s heat balance would be a probable consequence of nuclear war, were such an event ever to occur. The explosions in such a war might inject enough soot into the upper atmosphere to greatly reduce the amount of solar radiation reaching the surface for many weeks or months. The resulting temperature drop has been termed nuclear winter. A similar cooling may have occurred... 

After the nuclear winter was over, and mankind was eliminated from the planet, only Simon and the people of his neighborhood remained behind—saved by lessons stored in a lowly and near-extinct mushroom. 

Red Prometheus Engineering and Dictatorship in East Germany, 1945-1990, Dolores L. Augustine A Nuclear Winter s Tale Science and Politics in the 1980s, Lawrence Badash Jesuit Science and the Republic of Letters, Mordechai Feingold, editor... 

Dust in air. Will ash from your company s smokestack fall on your company s property, in the nearby town, or in the ocean How long would a nuclear winter last ... 

In these examples it is impractical to measure the actual process. The particles are either too small (approximately 1 / m for some dust) and/or the terminal velocity is too slow (nuclear winter is predicted to last 1-10 years). We would much rather take measurements on more convenient systems, such as a plastic sphere of diameter 1 cm falling through water. We will apply dimensional analysis to reveal how to scale the results of our experiments to interesting but experimentally inaccessible real processes. 

You are required to make some simple calculations here to estimate how long a nuclear winter would last (Sutija and Prausnitz, 1990). The large-scale generation of smoke and dust from urban and forest fires following a nuclear war would lead to a dust cloud in the stratosphere. The dust cloud would block solar radiation and cause a substantial reduction in temperature (as much as 20-40 °C) over large parts of the world (Turco et ai, 1990). Assuming that each dust particle diameter is 10 pm and that each particle settles Independently of the others, determine the duration of the nuclear winter if the particles have been carried to a height of 50 km by the nuclear blasts and subsequent fires. The particle density is 2 g/cm. (Ans. 105 days.)... 

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