Popular search engine Google celebrated World Earth Day 2013 on April 22 with an interesting and interacting 3D doodle which intends creating awareness against a common enemy called “climate change”. Earth Day 2013 aims to raise awareness among the people on global warming and provides solutions to the people to counter climate change.On Monday visitors to the Google search page were greeted with the doodle which has a play button that can play-pause the sun or moon in four different images depicting the four seasons of autumn, winter, spring and summer. By clicking the play button one can see the moon in its crescent, half, full and gibbous phases.The animated doodle with the world Google drawn through a landscape also has animals that emerge by clicking the button and that includes a bear, a badger, fish, ants, birds and fireflies. Rain, snow and wind can also be experienced. A row of dandelions on the left is shaped like a “G”, then two caves each depicting an “o”, again a “G” in the form of a lake, a tree symbolizes the “L” and a stream from the lake shaped like an “E”.Once the play button is hit, the sun starts moving to the west to set and it coincides with rising of the moon. As night turns into day the seasons too change. If the clouds are clicked it starts to rain and if the clouds are clicked during winter it starts to snow. One can make the wind blow, make a bear or badger come out of the cave, see a moving colony of ants or enjoy birds in flight.This is the 13th Google doodle to celebrate Earth Day since it was launched forty three years ago. Each year the Earth Day is celebrated on April 22 to mark the anniversary of the birth of modern environment movement in 1970. It was the idea of the then US senator from Wisconsin, Gaylord Nelson after witnessing the ravages of the 1969 massive oil spill at Santa Barbara.He then designed a movement to create consciousness about air and water pollution which aimed at catapulting environmental protection on the political agenda. It produced results and on April 22 the next year about 20 million Americans took to the streets to demonstrate for a healthy sustainable environment.In 1990 Earth Day went global mobilizing 200 million people from 191 countries and paved the way for the 1992 United Nations Earth Summit at Rio de Janeiro and Mr. Nelson was honoured by the US president Bill Clinton in 1995 with the Presidential Medal of Freedom, the highest civilian award in the US for his role as Earth Day founder.