I’ve often mentioned my love for apocalyptic fiction. Now I can get my fix from reality. The Center for Strategic and International Studies released a new report entitled “The Age of Consequences: The Foreign Policy and National Security Implications of Global Climate Change.” It envisions three scenarios: “expected,” “severe”, and “catastrophic.” I haven’t read the whole report yet, so here’s Real Climate’s summary with my comments:

The “expected” scenario calls for 1.3 °C of warming globally above 1990 levels, by the year 2040. Changes in precipitation and sea level prompt migration at a scale sufficient to challenge the cohesion of nations. The potential responses to this scenario are broken down into specific regions with their particular historical and political settings. Just to pick a region at random, Nigeria in West Africa will suffer accelerated desertification with climate change, prompting intensified migration into the megacity of Lagos, which is itself threatened by sea level rise. Compounding Nigeria’s misfortune, there is oil in the Niger Delta, and as global oil supplies dwindle, the strife and corruption that oil brings a weak nation will only intensify.

This is highly conservative. 2°C of warming can only be avoided with action now.

In the “severe” scenario, the globe warms by 2.6 °C by 2040 and sea level rises about a half a meter. Scientists in 2040 conclude that the eventual collapse of Greenland and the West Antarctic ice sheets has become inevitable in the centuries that follow. Agricultural production declines in the arid subtropics and in increasingly flooded river deltas. Again to pick a random example from the report: the river systems in the American Southwest collapse, leading to impoverishment of Northern Mexico and increased migration pressure in the U.S. Resource stress in Latin American leads to a tendency toward populist, Chavez-type governments, and more extensive regions of de facto anarchy such as found today in parts of Colombia.

The river systems in the American Southwest are already collapsing, due to decreased snowpack. A brand new report in Science finally links water shortages in the West directly to climate change. I’m hightailing it back to nice wet New England as soon as I get my degree.

The “catastrophic” scenario assumes positive feedbacks in the carbon cycle to warm the planet by 5.6 °C by the year 2100, and sea level has risen by 2 meters. I feel compelled to note that if this is supposed to be a worst-case scenario, I personally can imagine worse in terms of sea level rise. In the social realm the crystal ball gets murkier as the report progresses from expected to severe to catastrophic, but one important ingredient in the prognosis for the catastrophic scenario is the migration of millions of people, a scale unprecedented in human history, potentially enough to undermine the stability of civilized governance. One participant recommended that we check out the movie Mad Max, only imagine it hotter.

Well, shit. Zero emissions now!