For anyone who spends much time walking around downtown Ann Arbor, it's hard not to have stumbled across one of David Zinn's whimsical sidewalk chalk drawings.

They often depict the adventures of a little green guy named Sluggo, who might be found playing in a pile of leaves, hanging out with a flying pig, or simply taking a coffee break.

In the artist's own words, they're lighthearted and trivial, and soothingly self-destructing. That is, they're meant to be temporary, to wash away with the next rain.

"He realized how satisfying it was to create temporary art in locations where it's just not expected — where you happen across it, where many people might not notice the drawing at all, but those who did sort of get that extra satisfaction of just looking in the right direction and getting that moment of surprise," said Marsha Chamberlin, chairwoman of the city's Public Art Commission.

Zinn and two other local artists were announced as this year's winners of the Public Art Commission's annual Golden Paintbrush Awards during Monday night's Ann Arbor City Council meeting.

The awards are given in recognition of public artworks that add interest to the cityscape, beautify the community and create a sense of place.

The two other awardees this year are University of Michigan art professor Jim Cogswell and Margaret Parker, who served on the Public Art Commission up until recently.

Cogswell was recognized for his large-scale mural work, dubbed the "Enchanted Beanstalk," at the new C. S. Mott Children’s Hospital. The monumental piece features imagery cut from vinyl and affixed to 660 windows on eight stories of the hospital.

"It covers 11,000 square feet of glass," Chamberlin said. "The designs are applied to the interior of the windows and are configured so that, when visible from the outside, they form an intricate, woven tapestry and connect between the levels by a clinging vine and other sort of rhythmic, sequential elements. The vines evoke the story of 'Jack and the Beanstalk.' "

At night, Chamberlin said, the mural enlivens the exterior of the building from a considerable distance. And from the inside, the vinyl is translucent. Under the direct sunlight of west-facing windows, she said, it has the effect of stained glass in the late afternoons.

The vinyl was fabricated by a local professional graphic shop and installed by Cogswell with the help of a student assistant over a period of six months

Cogswell has a number of other large-scale public artworks locally, including at the Bailey Library at Washtenaw Community College and at U-M's Ross School of Business.

Parker was recognized for her instrumental role in advancing public art in the city over the past several years and service with the Public Art Commission, including serving as its chair.

"There's probably not a public official in this room or anyone who has an ounce of civic interest or pride who has not been visited by Margaret Parker as she strove to create a vision for public art and a public art program in our city," Chamberlin said.

Chamberlin described Parker as impassioned, tireless and selfless in her dedication to public art, with a vision and enthusiasm that's been contagious.

"Through her efforts, the Public Art Commission was established," she said, giving Parker credit for attracting funding and working with city staff to develop a public art program.

"She was a guide to fellow commissioners on best practices," she said. "She worked with our first public art administrator to really get the business procedures and policies and establish the credibility of the public art program with artists and ensure the city excellent outcomes."

Chamberlin added, "She kept rolling with it for seven years and today we have a strong program that has built momentum, is getting results, so what more could you ask for?"

Ryan J. Stanton covers government and politics for AnnArbor.com. Reach him at ryanstanton@annarbor.com or 734-623-2529. You also can follow him on Twitter or subscribe to AnnArbor.com's email newsletters.