Musings: Rising Tide

The Garden Island today had an article about something that many of us who live on the windward side have been noticing for months: the ocean is coming closer and closer to the road at Wailua Beach.

The sea's advancement calls into question the wisdom of Mayor Bernard Carvalho's decision to locate the Path right on the beach. It's clear, given the current conditions, that there is insufficient width to construct the Path on the sand and ensure there's still some beach left for the public.

Though one expert says the long-term trend at that beach is toward accretion, even episodic erosion could jeopardize not only the Path, but the beach itself by interfering with the natural movement of the sand.

Now's the time for the mayor and the Path people to return to the drawing board and figure out another route. While the late Bryan Baptiste thought it would be cool to ring the island with recreational cement, current events associated with global warming show that to be a foolhardy concept.

Consider the new piece in Rolling Stone about how ice is Greenland is quickly melting:

The rapid loss of ice is only the latest in a chain of events that have upended conventional understanding of how the Earth's "cryosphere" – its frozen places – behave. Taken together, the events offer new insight into how fast the world's seas are likely to rise as a result of global warming...

"When I took my first course in glaciology," [Byrd Polar Research Center scientist] JasonBox says, "conventional thought had the reaction time of the ice sheets to heating on the order of 10,000 years."

But in a series of scientific epiphanies beginning in 2002, researchers using GPS have found that melting on the ice's surface can cause large sections of the ice sheet to break free of its moorings in hours, not millennia. In 2006, scientists discovered that ice was suddenly pouring into the ocean at twice the rate previously measured, spurred by a pulse of warm ocean temperatures that undercut the glaciers from below.

What's more, the ice sheet darkens as it melts, which works to further accelerate the melting.

Box had conservatively predicted that it might take up to a decade before the surface of Greenland's ice sheet melted all at once. That it actually happened in just a few weeks only underscores how consistently cautious ice scientists have been in forecasting the threat posed by global warming. Now, however, that caution is being replaced by well-founded alarm. "Greenland is a sleeping giant that's waking," says Box. "In this new climate, the ice sheet is going to keep shrinking – the only question is how fast."

And melting ice means rising seas – seas that in all likelihood are going to rise faster than scientists have predicted and cause more severe coastal flooding  much sooner than expected. It's time to stop pouring millions into shoreline infrastructure and start moving it mauka.