Raising a child requires hard choices and hard work. There are sacrifices and decisions along the way, and a wise person plans for eventualities based on the best information available.
Today, society faces a similar inflection point. But rather than the birth of a child presenting a stark reminder of the need to make difficult decisions, it is the voice of future generations saying, “Choose now. Choose wisely. Our future is in your hands.”
The United Nations Intergovernmental Panel on Climate Change new Sixth Assessment Report is striking in the clarity of its key message: It is “unequivocal” that human influence has warmed the planet and that widespread, rapid changes have already occurred in every region of the globe as a result. The scale and rate of changes are “unprecedented” in relation to the past hundreds to thousands of years. And there are more changes on the way.
Each of the last four decades has, in sequence, been the hottest decade on record. Anyone under the age of 40 has lived in a world unlike anything our ancestors experienced. And our children will inherit a world unknown to any human that has ever lived. The list of changes they will face is long and sadly familiar by now — and includes extreme heat, persistent drought in some areas and flooding in others, more powerful and frequent hurricanes.
The report calls special attention to new sea level rise risks. Here in coastal Massachusetts — and anywhere around the world — a child born today could live to see their world completely reshaped by steadily encroaching seas within the coming century if we do nothing today. Today’s high tide “nuisance flooding” is likely to become the year-round norm within just a few decades. In fact, all of the sea-level forecasts in the report track very closely to one another and predict about one foot of additional rise over the next 30 years, and then diverge widely depending on how likely nations are — or are not — willing to reduce carbon emissions worldwide. The report also points out that instability of certain Antarctic ice sheets in the face of continued, rapid warming has the potential to raise sea level more than twice as fast and as high as projected in any prior IPCC report.
Indeed, all predicted scenarios show that increases are likely to exceed the ability of natural accommodations to coastal flooding, such as salt marshes, to migrate with the changing coastline, something that will not be solved by building seawalls or other hard structures. Recent studies have shown that New England will experience sea level rise significantly greater than the global average.
The IPCC report also considers ways that the ocean might be able to help, if action is taken quickly so that higher rates of future warming are not locked in for future generations. The surest path to limit warming and other impacts such as ocean acidification involves adopting net-negative carbon emissions, in which governments and industries remove more greenhouse gases from the atmosphere than they put there, and store it safely elsewhere, including perhaps in the deep ocean or beneath the seafloor.
But ocean-based strategies should not be enacted without a careful assessment of their long-term viability and potential impacts to the marine environment. Before such strategies are considered, there must be in place comprehensive, scalable, and long-term coastal and ocean monitoring systems that track ocean health and vital signs, to ensure the welfare of future generations.
A measure of courage is required from us now. To hand this world to our children in a responsible manner, people should adopt the same stark and unflinching language that the IPCC has used to describe the state of our climate. Governments must be unequivocal in their policies to reverse this change by taking unprecedented action. And we in the science community must demonstrate a greater degree of courage and commitment to seek out bold new solutions, and to communicate them with greater force and clarity.
Peter B. de Menocal is the president and director and Richard W. Murray is the deputy director and vice president for Science and Engineering at the Woods Hole Oceanographic Institution.