In one of the memorable lines in everyone’s favorite 1940s movie, Rick tells Ilsa, “We’ll always have Paris”. Well, maybe not.

On June 1, in an in-your-face expression of American exceptionalism, the current President announced that our country would withdraw from the Paris climate agreement, joining Nicaragua (which thought that the pact did not go far enough) and Syria (which has other things on its mind). This was in opposition to the other 195 countries in the world that have endorsed and are relying on the Paris accord to address the existential threat posed by global warming.

To paraphrase the Princeton bioethicist Peter Singer, this decision represents a moral failing of the most serious kind.

Truth be told, though, the Paris agreement itself is a questionable framework on which to hang the fate of the planet. In December 2015, 98 per cent of the nations in the world agreed in Paris to voluntarily start down a path to reduce greenhouse gas emissions to a level that would hold global temperature rise to 2 degrees centigrade by the end of the century (with an aspirational goal of holding that temperature rise to 1.5 degrees ). Note that 2 degrees centigrade has long been held to be dangerous territory.

Even at the time of the signing of the accord, achievement of this goal was highly unlikely. Global temperatures (average atmospheric temperatures above land and ocean) had already risen 1 degree centigrade above pre-industrial levels, and a warming of 1.5 degrees centigrade by the year 2100 is already locked in by the volume of greenhouse gases we have already emitted. In fact, if all of the parties to the agreement were to achieve their GHG reduction targets by the year 2030, but then kept their emissions constant, global temperatures would be highly likely to rise by at least 3.5 degrees centigrade above pre-industrial levels by 2100, with catastrophic consequences.

Even the GHG reductions agreed to in Paris, moreover, are very unlikely to be achieved. Take the U.S. goal – a 28 per cent reduction in overall emissions by 2030 from a 2005 baseline. There are a number of paths that we could take to reach that goal, but none are easy. For example, we could completely electrify our ground transport systems — no more gasoline-powered engines. Vehicles represent about 30 per cent of our national GHG emissions, so that would do the trick as long as the electricity to power them was carbon-free. However, since the automobile fleet turnover cycle in the US is 15 to 20 years long, this is very unlikely to happen. Alternatively, we could engineer a 40 per cent reduction in CO2 emissions from everything else in the energy ecosystem, including the impact of a growing economy — not an easy task. Other approaches to GHG reductions are equally daunting.

So what is to be done? Our country’s abandonment of its Paris commitment is most assuredly an abandonment of our former role as a global leader. It appears that other nations will step forward to lead at that level. For our part, state and municipal governments, including many in Massachusetts, have already signaled their willingness and resolve to fill the leadership vacuum in the U.S.

There is also an important role for grass-roots efforts. Here on the Vineyard, we have an established set of town and non-profit organizations working hard on the Island’s renewable energy future. As it has done with preservation of open space and environmental sustainability, Martha’s Vineyard can have an outsized influence as a model for other communities.

Recently, with recognition and approval by the Island towns, we have established an active-citizen-driven committee focused on sustainable energy on an Islandwide basis: the Vineyard Sustainable Energy Committee. VSEC’s role is not to supplant the efforts of existing town energy committees or the work of the Martha’s Vineyard Commission in this area, but to serve as a communications forum for information sharing and outreach, to develop a high-level sustainable and resilient energy plan for the Island, and to selectively advocate for sustainable energy policies and projects.

The World Meteorological Organization recently announced that global temperatures in 2016 were a record 1.1 degrees centigrade above pre-industrial levels, supplanting 2015 (which supplanted 2014) in that dubious category. On May 30, the concentration of CO2 in the atmosphere was 409.4 parts per million, the highest level in at least 800,000 years and 46 per cent higher than in pre-industrial times (the 18th century). It will never again be below 400 ppm in our lifetime, and it will without doubt be significantly higher.

Nevertheless, a recent survey of international experts in energy and climate reported that the majority of them were optimistic that we could indeed decarbonize our energy systems by 2050 and thus avoid the most catastrophic impacts of climate change. The VSEC members share that optimism.

With any luck, we’ll always have the Vineyard. At least most of it.

Rob Hannemann is a year-round resident of Chilmark. A former professor of engineering at Tufts University, where he taught courses in sustainable energy systems, he is chairman of the recently established Vineyard Sustainable Energy Committee.