Humboldt County ... Arcata is located in Humboldt County. The county had a population of 134,623 people at the 2010 Census. With it's population of 17,231 people, Arcata represented 12.8% of the county's total.
Here's a chart that shows what day Earth Day is celebrated from 2014 - 2021. Earth Day is celebrated around the world on April 22. Some cities start celebrating a week in advance, ending the recognition of Earth Week on April 22nd. Others host month long events to stress the importance of teaching about our environment. The United Nations celebrates Earth Day each year on the March equinox, which is often March 20, a tradition which was founded by peace activist John McConnell in 1969.
Some people celebrate Earth Day on the first day of Spring, which is the vernal equinox that occurs on or around March 21st. In 1970, U.S. Senator Gaylord Nelson proposed a bill designating April 22 as a national day to celebrate the earth. Since that time, Earth Day has been officially observed in April. At present, Earth Day is observed in 175 countries, and coordinated by the nonprofit Earth Day Network. The passage of the Clean Air Act, the Clean Water Act, and the Endangered Species Act are considered to be products associated with the 1970 Earth Day.