PACON Keynote Speaker James Hansen Says One-Meter Sea Level Increase ‘Almost Guaranteed’

Scientist sees ‘a very dangerous situation’

These might well have been the headlines in tomorrow's Honolulu newspapers if they had covered the Pacific Congress on Marine Science and Technology (PACON). But they didn’t, so the remarks of keynote speaker Dr. James Hansen, director of NASA’s Goddard Institute of Space Studies, about the effects of climate change on Hawaii and the rest of the planet are covered only here at Hawaii Energy Options.

Hansen may have said nothing that he hasn’t addressed previously, but his remarks about the inevitability of sea level rise would have been headline news in Honolulu. He’s a prolific writer and speaker (a Google search on his name returns 295,000 hits), and a March column by New York Times writer Andrew Revkin (a participant at the Blue Planet Summit) details Hansen’s recent assertions about the importance of carbon dioxide targets that won’t stop but only slow and hopefully reverse damaging climate change.

Hansen spoke using video and data links from New York to avoid laying down a big fat carbon footprint in flying to Honolulu for PACON. Most of his talk covered CO2 target levels (not more than 350 parts per million in the atmosphere; we're at 385 now), but his wind-up remarks about sea level change would have captured the attention of the local media.

Experts Are Worried

Hansen said that experts in this area will admit privately that a sea level rise of 1 meter is “almost guaranteed” due to the warming that's already occurred that is responsible for the ongoing thermal expansion of warming sea water, melting of sea ice and glaciers and other changes. He said he’s disappointed at the reticence of scientists to talk openly about it, a point he made emphatically in his “Scientific Reticence and Sea Level Rise” paper published in May 2007.

When asked about this reticence, Hansen noted “there’s little reward in ‘crying wolf’” because of the short-term negative impacts in doing so, whereas the gain in predicting something decades in the future won’t be realized until the same length of time has passed. He continued:

“I think that if you talk with all the people who work on the ice sheets and see what’s happening now, they’re getting very worried. If you look at the Paleoclimate record, you see evidence that sea levels went up 5 meters in a century, and that was with forcings much lower than what we’re discussing. I think it’s a very dangerous situation.”

Talking to Youth

Here’s another link on his “scientific reticence” theme, and we’ll let Google searches substitute for a detailed report on Hansen’s comments today. But his answer to the final question from the audience is worth some space here.

The questioner – Paula Keener-Chavis, director of NOAA’s Education Program, Ocean Exploration Program – noted Hansen’s rather downbeat assessment of climate change implications and asked what he tells children about the future and whether he can give them an overall message of hope. Hansen’s reply:

“That’s a good question. I have three grandchildren now, and I spent last weekend planting milkweeds and hollyhocks with a granddaughter and my one grandson. These are the plants that supply food for monarch and painted lady butterflies. You just have to get them to appreciate nature and understand the impact humans are having on the rest of the life on the planet. This education of the public – both adults and children – is really difficult partly because special interests are trying to educate them differently and convince them this climate issue is either wrong or greatly exaggerated. So it’s a problem we’re struggling with all the time, and I don’t claim to have a good answer actually.”

The answer Hansen did offer was unquestionably sobering for anyone concerned about their children’s and grandchildren’s futures.