By Harold Brown
Hurricane Sandy has been described as a harbinger of what comes with rising seas: the inundation of coastal cities, devastating storm surges, destruction of coastal wetlands and abandonment of land. The story is simple: Glaciers melt and oceans warm, causing seas to rise.
The reality, however, is anything but simple. The sea has been rising since the last ice age, but at a variable and poorly known rate. Long-term measurements are necessary to establish an accurate trend, but measurements were few in the 19th and early 20th centuries, especially in the Southern Hemisphere. More than two thirds of the 322 world sea level records listed on the National Oceanic and Atmospheric Administration (NOAA) Web site are 50…