Nuclear holocaust Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! ==Likelihood of complete human extinction== {{See also|Cobalt bomb|Nuclear winter}} [[File:US and USSR nuclear stockpiles.svg|thumb|The United States and [[Soviet Union]]/Russia nuclear stockpiles, in [[Historical nuclear weapons stockpiles and nuclear tests by country|total number of nuclear bombs/warheads in existence]] throughout the [[Cold War]] and post-Cold War era.]] Many scholars have posited that a global thermonuclear war with Cold War-era stockpiles, or even with the current smaller stockpiles, may lead to human extinction. This position was bolstered when nuclear winter was first conceptualized and modelled in 1983. However, models from the past decade consider total extinction very unlikely, and suggest parts of the world would remain habitable.<ref name=tonn>{{cite journal |author=Tonn, Bruce |author2=MacGregor, Donald |name-list-style=amp |doi=10.1016/j.futures.2009.07.009 |title=A singular chain of events |journal=Futures |volume=41 |issue=10 |year=2009 |pages=706–714|s2cid=144553194 }}</ref> Technically the risk may not be zero, as the climatic effects of nuclear war are uncertain and could theoretically be larger than current models suggest, just as they could theoretically be smaller than current models suggest.<!--<ref name=bostrom2002/> "(i) For there to be an existential risk it suffices that we can't be sure that it wouldn't. (ii) The climatic effects of a large nuclear war are not well known (there is the possibility of a nuclear winter)" --> There could also be indirect risks, such as a societal collapse following nuclear war that can make humanity much more vulnerable to other existential threats.<ref name=bostrom2002>{{cite journal |author=Bostrom, Nick |title=Existential risks |journal=Journal of Evolution and Technology |volume=9 |issue=1 |year=2002 |pages=1–31, §4.2 |url=http://www.nickbostrom.com/existential/risks.html}}</ref> A related area of inquiry is: if a future nuclear arms race someday leads to larger stockpiles or more dangerous nuclear weapons than existed at the height of the Cold War, at what point could war with such weapons result in human extinction?<ref name=bostrom2002/> Physicist [[Leo Szilard]] warned in the 1950s that a deliberate [[doomsday device]] could be constructed by surrounding powerful hydrogen bombs with a massive amount of cobalt. Cobalt has a half-life of five years, and its global fallout might, some physicists have posited, be able to clear out all human life via lethal radiation intensity. The main motivation for building a cobalt bomb in this scenario is its reduced expense compared with the arsenals possessed by superpowers; such a doomsday device does not need to be launched before detonation and thus does not require expensive missile delivery systems, and the hydrogen bombs do not need to be miniaturized for delivery via missile. The system for triggering it might have to be completely automated, in order for the deterrent to be effective. A modern twist might be to also lace the bombs with aerosols designed to exacerbate nuclear winter. A major caveat is that nuclear fallout transfer between the northern and southern hemispheres is expected to be small; unless a bomb detonates in each hemisphere, the effect of a bomb detonated in one hemisphere on the other is diminished.<ref>{{cite book|author1=Max Tegmark|author-link=Max Tegmark|title=Life 3.0: Being Human in the Age of Artificial Intelligence|date=2017|publisher=Knopf|location=Doomsday Devices|isbn=9780451485076|edition=1st|chapter=Chapter 5: Aftermath: The Next 10,000 Years|title-link=Life 3.0: Being Human in the Age of Artificial Intelligence}}</ref> {{further|Human extinction#Probability}} Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page