Worst-hit would be the Sacramento Delta area: a giant inland sea would open up running from Gridley to near Merced. But the places where coastal and interior land would be inundated are some of the most-developed places in California, and damages would likely run beyond hundreds of triillions of dollars. The California coast is rugged and steep in many places, and along much of the state's coast a 21-meter sea level rise wouldn't change the map all that much. The map doesn't have a setting for 21 meters, so we've used the 20 meter setting to make our projections more conservative, if that is the right word. We've made use of a handy tool created a few years ago by, which you can explore easily. But we did wonder what a 21-meter sea level rise would mean to California.Īs it turns out, it would mean an environmental and economic catastrophe. We're not in a position to judge the veracity of Box's prognosis for our planet's ice caps, though he does have impressive research chops and credentials. He does tell Mooney, however, that we can postpone that eventual catastrophic melt by slowing down the activities causing the problem in the first place, especially burning fossil fuels.

That's 21 meters, or about the height of a six-story building.īox doesn't state when the rising seas will reach that point. According to Box, despite recent articles downplaying the threat of melting of the Greenland Ice Sheet, a deadly combination of increased atmospheric carbon dioxide, atmospheric methane levels already at record levels and increasing, and global soot pollution darkening ice sheets has already locked in enough melt in Greenland and Antarctica to cause 69 feet of sea level rise. Mooney quotes Ohio State glaciologist Jason Box as making the apocalyptic pronouncement, which seriously outstrips commonly-quoted estimates of sea level rise by a factor of at least three. If that's true, what would that mean for California? Science writer Chris Mooney offers an incredibly frightening prognosis for sea level in an article Thursday on the website Grist, quoting a glacier expert as saying human industrial activity has already locked in 69 feet of sea level rise. Long Beach Bay | Screen capture from Firetree flood mapping tool.

California sea of roses