Following up on Jamais' June 2004 post about the European Project for Ice Coring in Antarctica, or EPICA, new results published this week verify that "the relationship between climate and CO2 that had been deduced from the Vostok core appears remarkably robust," according to RealClimate.
Secondly, these results will allow paleoclimatologists to really look in detail at the differences between the different interglacials in the past. The previous 3 before our current era look quite similar to each other and were quite short (around 10,000 years). The one 400,000 years ago (Marine Isotope Stage 11, for those who count that way) was hypotheisied to look more like the Holocene and appears to be significantly longer (around 30,000 years). Many of the details though weren't completely clear in the Vostok data, but should now be much better resolved. This may help address some of the ideas put forward by Ruddiman (2003, 2005), and also help assess how long our current warm period is likely to last.
The study shows that carbon dioxide levels have increased significantly over the last two centuries, from 280 to 380 parts per million. According to Edward Brooks, a geosciences specialist at Oregon State University, quoted in an Associated Press article, "There's no natural condition that we know about in a really long time where the greenhouse gas levels were anywhere near what they are now. And these studies tell us that there's a strong relationship between temperature and greenhouse gases. Which logically leads you to the conclusion that maybe we should worry about temperature change in the future."
An article in the UK Guardian, linked from a comment on the RealClimate post, refers to analysis of cores drilled along the eastern seaboard, suggesting that "oceans will rise nearly half a metre by the end of the century, forcing coastlines back by hundreds of metres." Professor Kenneth Miller is quoted as saying there's little we can do at this point to stop the sea level from rising, prompting a clarification from Gavin Schmidt at RealClimate: "Miller's point is that sea level will continue to rise under any conceivable scenario (as seen in the 'committed climate change' papers by Meehl et al and Wigley earlier this year....while cuts in emissions will not prevent sea level rise, they may prevent the worst case scenarios in the medium to long term."
MSNBC also published an article, "Tiny bubbles, rising seas point to warming."
Mitigation/Adaptation: Jamais' post, What's the Best Path to CO2 Reduction, has good information on potential mitigation strategies, as well as the WikiPedia entry on Mitigation of global warming. The leading global effort at mitigation, of course, is the Kyoto Protocol. As Jamais posted when the Kyoto Treaty became active, "Kyoto is a reframing exercise, a memetic engineering project. It forces us to respond and, by being transparent in its failings, forces us in turn to come up with something better."
So do we give up now? Is it concensus that there is nothing we can do to stop the oceans rising?
As far as I know, the overwhelming consensus has been exactly that for a long time now. Even if we stopped all emissions today, we also will still face some warming/climate change.
How much they will rise under different scenarios, and how much we can do to mitigate and/or adapt are all still being debated.
This is no time to give up though: we're finally winning the public perception battle.