NEWARK, New Jersey — During the day, parking lots in downtown Newark are jammed with cars belonging to government and corporate office workers. To some observers, the full lots might seem a useful facet of urban life and a sign of a healthy city economy.

But not to everyone. At night and during the weekends, the surface lots are desolate, quiet stretches of black and cracked asphalt. Repeat this scene in other parts of this city’s downtown and you end up with many residents and urban planners complaining they are a form of urban blight. They sap the vitality of an area on the cusp of major gentrification, critics say.

There is also an economic cost: The dead spaces that cars take up don’t generate nearly enough in taxes for Newark’s coffers, and most of all, they might encourage crime. Some residents don’t feel safe around the empty lots late at night.

“I have been here for more than 20 years, and [crime] has been increasing. The synergy there is that with the crime increasing, so are the surface parking lots,” said Madeline Ruiz, an architect. “I used to feel safe.”

Nor are Newark residents alone. Many cities across the U.S. are also confronted by landscapes filled with similar ugliness, posing problems with stormwater runoff and acting as heat sinks.

Miami and Detroit suffer the same problem, says Streetblogs , a website devoted to transportation issues. This year, Rochester, New York, won the blog’s Golden Crater award, which recognizes the city with the most excessive surface parking. An aerial view of Rochester’s core shows a patchwork of blacktop and islands of buildings.

A study from the University of Connecticut compared three U.S. cities with modest parking lot growth and three with triple-digit percentage increases. It found that lot-dominated cities suffered economically. One example was Hartford, Connecticut, which loses $50 million a year thanks to its lots.

“Surface parking lots are holes in the urban fabric,” said Donald Shoup, a professor of urban planning at UCLA and an expert on parking issues in cities. “They don’t produce as much for the economy. The parking lot barely employs a few people compared to a restaurant. A parking lot doesn’t draw anybody to downtown.”