Photos of North Shore homes ready to fall into the ocean are certainly attention-grabbing, especially when placed with articles about sea level rise (“Turning the tide?” Insight, Star-Advertiser, Sept. 18). A news story that same day, “Preserving Waikiki,” contained a quote: “The city says that we need to plan for a 3.2-foot rise by 2030.” And a commentary by a University of Hawaii professor stated that “the potential for over 6 feet of sea level rise … is our reality now” (Island Voices, Sept. 18). Such statements bring to mind the story of Chicken Little whipping the populace into mass hysteria: “The sky is falling!”
Climate change is undoubtedly real and the sea level has been rising for thousands of years. But should state and county policies in response to climate change be based on facts or conjecture?
Starting with causes of beach erosion, we all know that big storms can cause surges exceeding 20 feet — especially on the North Shore. The second cause is tides, with the moon’s gravity being the primary cause. Tidal activity is perhaps 2.5 feet on any given day, and even higher during king tides.
Third is sea level rise (SLR), but how much? Based on very accurate satellite data from 1993 to 2021, the average rate of increase has been 0.13 inches per year, which equates to 1.3 inches per decade or 13 inches per century. And the trend has been very steady.
A bad day for a North Shore house might be the result of 20-foot storm surge, possibly coinciding with a 3-foot-high tide, plus a 1.3-inch rise in sea level over the past decade. The conclusion as to relative causation is obvious, but that’s certainly not the rhetoric. SLR is being used as the pretext for proposing sweeping land-use restrictions. Convenient to cite but perhaps misleading?
As lamented by theoretical physics professor Steven Koonin in his book “Unsettled,” “much of the public portrayal of climate science suffers from … an effort to persuade rather than inform.” Perhaps policy leaders should recognize the techniques and scare tactics being used to advance certain agendas. It has been stated that the hunt for veracity should begin with examining that “the more deviant the facts, the more improbable.” Based on the facts outlined above, it would take more than 500 years for the sea to rise 6 feet, absent some very dramatic acceleration.
Should anecdotal incidents of a few homes built on sand on less than one mile of shoreline dictate a major expansion of restrictions along the remaining 111 miles of Oahu shoreline? The Honolulu City Council is considering Bill 41, which would have sweeping implications — a 50% increase to the recently enacted statewide setback of 40 feet, plus an erosion-based formula that could mean setbacks totaling 130 feet. On an 80-foot frontage lot, that means no construction on more than 10,000 square feet.
Testimony on Bill 41 surfaces numerous concerns, such as forced dilapidation of existing structures. And the financial impact of proposed setback increases could easily amount to billions. Is the City and County prepared to pay fair compensation for such takings? And what about implications to City and County property tax revenue resulting from reduced property assessment values?
No one can predict the future with certainty, but our view is that the sky is not falling. Are we being led astray by those who use endangered North Shore houses as pretext for sweeping land use restrictions, when SLR is actually a minimal factor?
Perhaps it’s time for the City Council to consider tabling Bill 41 to see if the pace of SLR over the next few years is consistent with the historic rate of 1.3 inches per decade or the conjectured rate of 3.2 feet by 2030. And as for the further conjectured rate of 6 feet being “our reality now,” we leave judgment as to the credibility of this statement to the reader.
Retired U.S. Air Force meteorologist John Kim and retired businessman Ed MacNaughton represent the Practical Policy Institute of Hawaii.
