worse than we thought – tides!

Global sea levels have risen faster than previously thought over the past century, suggesting that climate change is having a greater than expected impact on the rising oceans, a study has found.

Previously, researchers gathered tide gauge records from around the world, averaged them together from different regions and then averaged those rates together again to create a global estimate, said Dr Eric Morrow of Harvard University.

“But these simple averages aren’t representative of a true global mean value. Tide gauges are located along the coasts, therefore large areas of the ocean aren’t being included in these estimates and the records that do exist commonly have large gaps,” he said.
Independent, 15 Jan 2015