To meet the bold new climate change goals put in place last year, California will work to put millions of electric cars on the road, revolutionize its dairy industry and generate half of all power from solar panels and other renewable sources.

But those efforts will come up short, warn state regulators, without dramatic changes to how Californians live and travel.

The state has pledged to reduce its greenhouse gas emissions to 40% below 1990 levels by 2030. To do so, Southern Californians will have to drive nearly 12% less by that date than they did five years ago, cutting their miles on the road every day from 22.8 to 20.2, according a Los Angeles Times estimate based on data from state and regional climate and planning officials.

These driving reductions mean that Californians will have to walk, bike and use mass transit much more frequently than they do now. By 2030, residents will have to travel by foot four times more frequently than they did in 2012, alongside a nine-fold increase in bicycling over the same time, and a substantial boost in bus and rail ridership, climate officials say.