WE ARE THE WORLD : Great L.A. Clean Up begins with Earth Day activities close to home.

Mother Earth, make way for the 1993 Great L.A. Clean Up.

Earth Day, marking its 23rd anniversary this year, is usually set aside as a time to think clean and green, spruce up the outdoors, and resolve to revere the globe’s resources. But this year, organizations in the South Bay join groups throughout Los Angeles in a broader celebration of the environment through the 1993 Great L.A. Clean Up.

Earth Day is officially commemorated next Thursday, but organizations citywide will sponsor events beginning today through May 2 as part of The 1993 Great L.A. Clean Up. The cooperative effort by more than 140 community, government, environmental and entertainment organizations encompasses Earth Day and the anniversary of the riots that erupted last spring.

More than 100 events, including coastal cleanups and graffiti paint-outs, festivals, concerts, lectures and vigils, are aimed at restoring the city’s natural and urban environments while easing community tensions.

Here is a partial list of South Bay events that have been scheduled as part of Earth Day or the Great L.A. Clean Up.

EL SEGUNDO

* The El Segundo coastal sand dunes will get a lift from restoration crews organized by Heal the Bay from 9 a.m. to noon Saturday, April 25 and May 1, and by Rhapsody in Green on Sunday, April 24 and May 2. Information: (310) 394-4552 or (213) 654-5821.

* Paint, pesticides and other toxic household waste can be safely disposed of at the Household Hazardous Waste Roundup on April 24 from 9 to 11 a.m. in Parking Lot G of Hughes Aircraft at Sepulveda Boulevard and Hughes Way. Information: (310) 699-7411 Ext. 1622.

REDONDO BEACH

* Everything you ever wanted to know about decomposing refuse can be learned at a composting class taught by the City of Redondo Beach at 10 a.m. Saturday in Wilderness Park. Information: (310) 372-1171.

* A coastal cleanup sponsored by the Surfrider Foundation is scheduled for April 24 from 9 to 11 a.m. in front of the Chart House Restaurant. Divers will clear debris underwater while land crews scour the beach. Water sampling will be demonstrated. Information: (310) 540-5356.

SAN PEDRO

* The public is invited to the Cabrillo Marine Museum Beach Cleanup and Activities Fair from 8 a.m. to 4 p.m. April 24. After the cleanup, visitors can tour the museum, visit information booths and view videos on ecology and the environment. Information: (310) 548-7563.

TORRANCE

* The South Bay chapter of Gray Panthers will present several speakers who will address environmental problems at a meeting Saturday at 9:30 a.m. Information: (310) 370-2140.

* A free seminar, “How, What, Why Recycle?” sponsored by Torrance-South Bay YMCA in association with VOICE, will address the importance of recycling on Monday at 7 p.m. Information: (310) 325-5885.

* Friends of the Earth will host Earth Fest ’93 Tuesday from 11 a.m. to 2 p.m. on the library lawn of El Camino College. The event will feature speakers, food and music. Information: (310) 327-1251.

* Friends of Madrona Marsh welcome the public to the third annual Earth Day Walk on the Madrona Marsh preserve beginning at 4 p.m. Thursday. A brief dedication of the temporary Natural History Center is also planned. Information: (310) 32MARSH.

* Learn how to compost and recycle while enjoying music by the Mineral Spirits on Thursday from 7 p.m. to 9:30 p.m. in the Torrance Cultural Arts Center Meeting Hall. Larry Agran, 1992 presidential candidate and former mayor of Irvine, and representatives from the Sierra Club and Heal the Bay will speak. More than 30 high school and community conservation organizations will provide exhibits on topics from organic gardening to alternative transportation. Information: (310) 545-1384.

WILMINGTON

* Try spotting a mud turtle or red-winged blackbird during Discovery Day at Ken Malloy Harbor Regional Park from 10 a.m. to 3 p.m. April 24. The day’s events, co-sponsored by the park’s advisory board and the Los Angeles City Department of Recreation and Parks, include canoe rides, nature walks, a photography exhibit and hands-on workshops for children. A free concert will be given by the Palos Verdes Symphonic Band at 11:45 a.m. outside the boathouse at the south end of Machado Lake. The park is at 25820 S. Vermont Ave. Information: (310) 548-7515.

For a complete schedule of events throughout the city, call the 1993 Great L.A. Clean Up at (310) 821-2722.