There are two causes of sea level from rising temperatures, melting ice and thermal expansion, which are roughly equal. But without the temperature rise the sea will do nothing. Then a small bounce back from the loss of ice from the ice age adds a little more. Local differences are also down to tectonic plates, so Britain is tilting so one side will go higher and the other lower. Likewise many low lying islands are on a tectonic plate which is falling, but that of course is independent of the temperature. But (although they are not entirely reliable are many times more consistent than the comparable temperature records as seen in my previous entry) local sea levels are pretty easy to follow as you only basically need a man with a pole and a tape measure and far harder to cheat. Satellites do it as well now, tide gauges/bobs and are then collected and added to get the world averages per year. But as local levels can only cause local disasters here is Tuvalu's. Where is the cause of the reason they are demanding our money again?
Bottom line, you can check yourselves, the land ice (Arctic ice can't cause the rise as only Greenland contains the stuff which can and that's not likely to melt in our lifetimes, so is irrelevant), and 90% is in Antarctica which is steadily growing. If Antarctica continues to grow, without a vast and sudden melt of the Greenland glacier there is nothing there to cause a rise. Where could it come from? And for the thermal expansion you'd need (I'm sure the equation is around) a temperature rise so much beyond anything currently possible it isn't worth considering. What's the point of thinking about something which both isn't happening and whatever the Hansens of this world are spouting are almost impossible, not because of individual opinions but current and historical data. Plus the prediction of long term temperature trends beyond the huge thousands of year ice age cycles are impossible as they are chaotic. And before anyone blames CO2 the 33C greenhouse effect the UN use has 1C from CO2, which would double if it doubles unless it has positive feedback. It has increased 50% already, and the attributed rise from 0.7C was 0.4, less than expected. There are no new phenomena to cause a delayed or surprise feedback, it was never expected to be, it is either there or not, and with that experiment half run observation tells you what exactly?