Global "nuclear winter" also due to regional nuclear war
Even a localized nuclear war with around 100 15-kiloton bombs would have catastrophic effects on the global climate - far beyond the actual conflict area. This was the result of the simulations by a research team led by Owen Toon from the University of Colorado in Boulder. Around 2.6 to 16.7 million people worldwide could fall victim to the consequences of climate change, calculated the scientists, who concentrated primarily on the consequences of the smoke that would be released into the atmosphere by firestorms in the cities hit.
Previously, they had calibrated their climate models using known data on the effects of volcanic eruptions, because large eruptions have similar consequences for the climate, as they also emit very large amounts of dust and ash into the atmosphere. For example, a year-long drop in average temperature and resulting crop failures and famine followed the 1815 eruption of Indonesia's Tambora volcano, considered one of the largest in the last five hundred years. But a nuclear war on the scale described by the authors would disrupt the climate even more severely and for longer, the calculations show.
According to the researchers, the "saber rattling" of the young nuclear powers North Korea, India and Pakistan as well as growing tensions in the Middle East are fueling fears of such a regional nuclear conflict. Up to forty countries could use their plutonium stocks to build up a sufficiently large nuclear weapons arsenal. Moreover, with fifty Hiroshima-type bombs, the amount of explosive power that Toon and his colleagues used as a basis for the scenarios is so small that even the smallest nuclear powers could muster it in a crisis.