Some quotations from the above Scientific American article
...civilization itself could disintegrate.
...breakdown of governments and societies.
In the 20th century the main threat to international security was
superpower conflict; today it is failing states.
A fourth of this year's US grain harvest - enough to feed 125 million
Americans or half a billion Indians at current consumption levels -
will go to fuel cars.
The grain required to fill a 25-gallon SUV tank with ethanol could feed
one person for a year.
...leading to an epic competition between cars and people for
the grain supply...
The world's most populous nation may soon be importing massive
quantities of grain.
....for every one degree Celsius above the norm, wheat, rice and
corn yields fall by 10 percent.
Similar in scale and urgency to the US mobilization for
World War II, Plan B has four components: a massive effort
to cut carbon emissions by 80 percent from their 2006 levels by
2020;the stabilization of the world's population at eight billion
by 2040; the eradication of poverty; and the restoration of
forests, soils and aquifers.
....meeting these goals may be necessary to prevent the collapse
of our civilization.
Can we stabilize population before countries such as India,
Pakistan and Yemen are overwhelmed by shortages of the water
they need to irigate crops?