The report addresses key research findings from the Earth elements of sky, sea, ice, land, life and people. The report points to human impacts on the environment, such as the use of fossil fuels, agriculture, land use as well as the use of aerosols as factors in the Earth's changing climate. They say it is "extremely likely that human activities have had a net warming effect since 1750." Researchers say the evidence of a changing planet is not solely based on one field of science. They note that a wide range of scientists - from ecologists to social scientists - have documented examples of climate change's impact on the Earth.