To me, there is no other issue as important as global warming. While terrorism, education and healthcare loom, nothing is as important to humankind's survival as reducing greenhouse emissions. The Washington Post is issuing a series covering the subject, and is by far the most informative and actionable piece I've seen on the subject. This issue will require a global effort and leadership by the United States on a scale greater than has every been accomplished.
Today's articles are fantastic and includes tangible steps on what it will take to halt global warming. There is also a nice overview of the pieces of legislation under consideration that would require reductions in greenhouse commission. And of course there is a financial cost to all of this, which is all worth it. Track the series here, along with some nice interactive maps further articulating what it will take.