Compléter environmentVersion en ligne gap filling par Katalin Karakó 1 We experience weather extremities more and more often . A climate is bringing about a series of changes . Polar icecaps may , which would result the sea rising . Crop are decreasing , which may lead to famines . It is in all our interests to prevent an ecological . According to , global carbon dioxide must be cut by 50% by 2050 . One way to do that is through energy . This means developing that use less electric and designing vehicles with lower fuel . We must also make use of energy sources , like the Sun , the wind and the water . These do not carbon dioxide into the : at the same time they are at our in unlimited , unlike fuels .