President Obama gave his first major speech on climate change today at the United Nations, part of a special session convened by U.N. Secretary General Ban Ki-moon. The reason for the session? Lack of speed in international negotiations to address climate change.

You can see the president's speech here:

In addition to reaffirming the U.S. commitment to addressing climate change, the president listed some recent accomplishments: new efficiency standards for all vehicles, billions of dollars for renewable energy development, and the nation's first mandatory greenhouse gas reporting system. He even noted a plan to work with the world's other largest economies, known as the G20, to "phase out fossil-fuel subsidies so that we can better address our climate challenge."

Do you really want to start messing with the atmosphere? If not, then stop emitting so much CO₂. Or so argues the U.K.-based Royal Society, the same people who brought you Isaac Newton, Charles Darwin and Stephen Hawking. A new report by the Society analyzes so-called geoengineering—"the deliberate large-scale manipulation of the planetary environment," or consciously tweaking Earth's climate in an attempt to stave off global warming—and finds that it is feasible and worth studying carefully, but probably not something we want to get involved in.

Artificial volcanoes, mirrors in space or other climate-altering schemes might be the last, best hope for mankind if we don't get started reducing greenhouse gas emissions pronto—specifically a 50 percent reduction (at minimum) in global emissions from 1990 levels by mid-century, according to a 12-member panel convened by the Society. "Geoengineering and its consequences are the price we may have to pay for failure to act on climate change," said report chair and climate modeler John Shepherd of the University of Southampton in a prepared statement. "Used irresponsibly or without regard for possible side effects, geoengineering could have catastrophic consequences similar to those of climate change itself."

The history of engine improvements in the U.S. has tended primarily in one direction: raw horsepower. Engines have gotten bigger and more powerful over time—and that's certainly what automakers have used as a key selling point. But U.S. automaker Ford has decided to take turbocharging and direct fuel injection in another direction: fuel efficiency.

Yesterday, Ford began production of what it's calling the EcoBoost engine: a new gasoline motor that employs turbocharging, direct fuel injection, variable timing in the valves that control fuel and exhaust flow to make a smaller, lighter six-cylinder engine perform like an eight-cylinder engine.* When these technologies are combined, "you can now significantly downsize the engine," says mechanical engineer Dan Kapp, Ford's director for power train research. "The fuel efficiency comes from a much smaller displacement engine providing equal or, in most cases, superior performance to the engine you're replacing."