The global average level of the sea could increase by almost 2.4 meters by 2100 and 15.2 by 2300 if greenhouse gas emissions remain high, forcing humanity into an unfortunate scenario that could see most coastal cities disappear.
According to scientists, since the start of the century, global average sea-level has risen by about 0.2 feet.
The new study makes eery warnings backed up by science. With 11 percent of the world’s 7.6 billion people living in areas less than 33 feet above sea level, rising seas pose a major risk to coastal populations, economies, infrastructure, and ecosystems around the world, the study says.
Under moderate emissions, central estimates of global average sea-level from different analyses range from 1.4 to 2.8 more feet by 2100, 2.8 to 5.4 more feet by 2150 and 6 to 14 feet by 2300, according to the study, published in Annual Review of Environment and Resources.
Sea level rise varies by location and time, and scientists have developed a series of methods to reconstruct past changes and project future ones.
But despite the different approaches, a clear story is emerging with respect to the coming decades: from 2000 to 2050, the average sea level in the world will probably increase from 15 to 25 centimeters, but it is very unlikely to increase by more than 45 centimeters.
Beyond 2050, projections are more sensitive to changes in greenhouse gas emissions and to approaches to project changes in sea level.
“There’s much that’s known about past and future sea-level change, and much that is uncertain. But uncertainty isn’t a reason to ignore the challenge,” said study co-author Robert E. Kopp, a professor in the Department of Earth and Planetary Sciences at Rutgers University-New Brunswick and director of Rutgers’ Institute of Earth, Ocean, and Atmospheric Sciences.
“Carefully characterizing what’s known and what’s uncertain is crucial to managing the risks sea-level rise poses to coasts around the world,” added Kopp.
Scientists used case studies from Atlantic City, New Jersey, and Singapore to analyze how current methods for reconstructing sea level changes in the past can limit future global and local projections.
They also discussed approaches to the use of sea level scientific projections and how precise projections can lead to new sea level research questions.