Drawing, the art or technique

Global warming is the mainly human-caused rise of the average temperature of the Earth's climate system and has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.[1] It is a major aspect of climate change which, in addition to rising global surface temperatures,[2] also includes its effects, such as changes in precipitation.[3] While there have been prehistoric periods of global warming,[4] observed changes since the mid-20th century have been unprecedented in rate and scale.[5]