But when he looked for ways to shrink his environmental footprint, the 50-year-old found few practical instructions. Individuals will need to change the way they consume, travel and work if carbon emissions are to fall enough to keep the world from warming by more than the 1.5 degrees Celsius (2.7 Fahrenheit) that's considered safe. "We found that his footprint was pretty enormous," said Finkbeiner, who attributed a substantial share of emissions to Gratzel's extensive business travel. With the help of Finkbeiner and two environmental groups, Gratzel set about shrinking that footprint. Reusswig has spent the last year monitoring the efforts of 100 Berlin families to shrink their carbon footprint.

Source: ABC News December 11, 2018 10:20 UTC