advertisementadvertisementSea levels rising a few millimeters every year hardly sounds ominous, until NASA program scientist Nadya Vinogradova Shiffer offers a little perspective.advertisementadvertisement“When my kids asked me if three millimeters is a lot, I told them that is equivalent to adding an extra 300 trillion gallons of water every year,” she says. “If you put this water in milk jars, that would cover the distance from the sun to Pluto and back several times.”For 30 years, an uninterrupted sequence of international Earth-observing satellites has tracked —a gauge of human-induced...…advertisementadvertisementSea levels rising a few millimeters every year hardly sounds ominous, until NASA program scientist Nadya Vinogradova Shiffer offers a little perspective.advertisementadvertisement“When my kids asked me if three millimeters is a lot, I told them that is equivalent to adding an extra 300 trillion gallons of water every year,” she says. “If you put this water in milk jars, that would cover the distance from the sun to Pluto and back several times.”For 30 years, an uninterrupted sequence of international Earth-observing satellites has tracked —a gauge of human-induced...WW…