Because the past three years have shattered temperature records, researchers have been exploring whether global warming is accelerating, and if so, why. Many scientists agree that the rate at which it is increasing has picked up. This is mainly because of a reduction in air pollution following the introduction of fuel regulations for international shipping (which has resulted in fewer pollutant particles that reflect sunlight into space and seed insulating clouds).
Every Sunday in Bogota, streets across the city are closed to cars and transformed into urban parks. Shirtless rollerbladers with boomboxes drift leisurely in figures of eight, Lycra-clad cyclists zoom downhill and young children wobble nervously as they pedal on bikes for the first time. This is perhaps the most visible component of a multipronged plan to clean up the Colombian capital's air.