By Huck Fairman
A question many, if not most, New Jersey shore home owners have asked themselves.
Following the arrival of our one-in-a-hundred years storm, superstorm Sandy, in October 2012, measurements of and predictions for, sea level rise along the Jersey shore are exceeding the global averages. While this is in part due to the state’s sinking coastal lands, there are additional factors contributing to our rising sea levels.
How to evaluate all of this was the subject of a local Sierra Club’s most recent talk at Mercer County Community College. Hoping to separate science from speculation, it invited Rutgers’ distinguished professor Kenneth Miller, of the Department of Earth and Planetary Sciences, with a PhD in Oceanography, to speak both about sea level rise, and about the general condition of our atmosphere, oceans and planet.
At the outset of his talk, Dr. Miller said those who were interested in learning about sea level rise need to first consider the data.
Science, he cautioned, is not prepared to make specific, long-term projections, but what it can produce is data, and suggested trends the data supports. He also alerted the audience to the fact both global warming deniers and those warning of climate change have spun the data.
And so, Dr. Miller began by offering unvarnished data or, simply, measurements. The CO2 levels in our atmosphere have reached 409 parts per million (PPM) whereas in 1850, the CO2 level was 280. And just as clouds hold in the day’s heat, while clear skies at night allow the heat to rise into the atmosphere, so does man’s spewing large amounts of CO2 into the atmosphere hold in the solar radiation reaching the planet’s surface.
At the same time, where Arctic sea ice formerly reflected back 80-90 percent of the energy reaching it, now the exposed, darker Arctic Ocean absorbs much of it. Globally, our atmosphere has absorbed about 50 percent of the solar heat, and the oceans the other 50 percent.
Given these changes, it is not surprising for science to find global temperatures have risen significantly since 1980 and human beings are the cause. One projection science feels comfortable in estimating is if we continue increasing CO2 levels, this may well lead to a 3-degree global temperature rise by 2100.
However, the seemingly concurrent sea level rise has not one, but three related causes: (a.) the warming oceans cause thermal expansion; (b.) with Antarctic and Arctic lands losing ice (and its weight), those lands and ocean floors are rising, pushing up sea levels; and (c.) globally, melting glaciers send their water into the oceans, contributing as much as one-third of sea level rise. (However, in some cases, ocean floors are sinking, making precise measurements difficult.)
Along the Jersey shore, predictions for sea level rise range from 0.7 to 3.1 feet by 2100. But to demonstrate even small changes can result in major impact differences, Dr. Miller compared the storm tides of hurricanes Donna (10 feet), Irene (9.5 feet) and Sandy (13.9 feet).
But here again, there are competing factors. In New Jersey, ground water extraction has caused some lands to sink. Encroaching salt water kills some of the barrier vegetation, allowing storm tides to reach further inland. At the same time, the warming oceans fuel more powerful storms, with their destructive storm tides. And now, it appears the frequency of powerful storms is increasing. In March 2018, the shore experienced four powerful Northeasters in one month alone. Where storms, like Sandy, were considered one-in-a-hundred-years events, they may now be one-in-ten-years.
Given these changing realities at the shore, what can and should residents do about it? One response is to increase the use of Nature’s barriers, sand dunes and grasses, and also promote “beach nourishment.” Around bays and inlets, marshes should be cultivated to absorb the storm surges.
Another response is for residents to raise their houses. But there are different recommendations as to how high. Government recommendation is 7 feet, but Dr. Miller urged 11 feet would be safer.
But even if houses are adequately raised, what can be done to secure utility lines for electric and gas? Moreover, if streets are flooded, who will be able to reach or escape shore communities? And not only residents, but businesses and community buildings will be exposed.
Dr. Miller did not ignore the global challenges beyond the shore. Key, he noted, to global sustainability will be reducing CO2 emissions and controlling population growth. Excesses of either one can, as they have begun to, upset the balances we need to sustain the life we have known.
Dr. Miller doubted the efficacy of geo-engineering, although some technological breakthrough is theoretically possible. Less expensive, smaller nuclear power plants, and the means to deal with spent fuel, probably should become part of the mix to reduce emissions. But what he strongly urged is the role of leadership at all levels. It is essential in order to direct people and governments toward sustainable policies. He touted our current governor’s returning the state to RGGI, not as a solution in itself, but as the kind of leadership solving the crises needs.