For our coverage of the 40th anniversary of Earth Day, we spent a lot of time talking to people who work on the big picture -- sustainability leaders at large companies, people driving change at environmental NGOs, and so on.

But to get a look at how Earth Day celebrations take shape on the ground, we turned to the GreenBiz Intelligence Panel, our group of more than 2,000 executives and thought leaders in the area of corporate environmental strategy and performance.

We sent our panelists a short questionnaire about Earth Days past, present and future, and received, as per usual, an overwhelming number of thoughtful responses. Combined, these responses illustrate how environmentalism's big day takes shape in offices around the country.

How they Celebrate

It's perhaps not surprising that almost 73 percent of respondents say their firms recognize Earth Day in some way or other, and 52 percent say they're doing more now than they were five years ago.

What these companies are doing runs the gamut. Although there are, of course, a large number of "Every Day is Earth Day" types of non-responses, in the broadest sense, Earth Day-specific activities break down as the chart below shows.

Click for full-sized image.

Some examples of on-site events for employees include movie screenings ("No Impact Man," "Garbage! The Revolution Starts at Home"), competitions for personal sustainability efforts, company-wide lunches, bike-to-work days, and dumpster dives to showcase the amount of waste a company creates.

Other companies encourage their employees to volunteer in the community and/or for the environment on Earth Day; some contribute money to environmental causes, and some host customer- and public-facing events highlighting green projects and products that individuals can do every day.

Despite the ever-present concept of "Every Day is Earth Day," among our Intelligence Panel responses, only a tiny group thinks Earth Day is only a distraction from the other 364 days of the year or is too commercialized and shouldn't be celebrated at all.

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