Melting Ice Sheets Push Sea Levels Higher, Threatening Coastal Philippines

About 12.5 trillion tons of ice from glaciers in Greenland and Antarctica have melted since 1979, enough frozen water to stack ice 5 feet deep across the entire continental United States, according to a major scientific report. For the Philippines, an archipelago of over 7,000 islands, this is not just a distant polar concern. It is a direct threat to our shores, our farms, and our people.

A warming Earth is accelerating the melting of the planet's two major ice sheets. Five-sixths of the melt comes not from hotter air, but from warmer waters eating away at the ice from below and the sides, with glaciers flowing into the oceans, according to a study published in the journal Scientific Data. That is bad news for future sea level rise, the study's authors said.

What does the ice melt mean for sea levels?

All that melted ice turned into nearly 3 quadrillion gallons of water, which pushed global sea levels up about an inch since 1979, on top of other climate factors raising ocean heights, the report said. An inch may not sound like much, but for every third of an inch of sea level rise, another 2 to 3 million people get flooded at least once a year, said lead study author Ines Otosaka, an ice scientist at Northumbria University in England.

Consider that many of our own coastal communities, from Manila Bay to the Visayas and Mindanao, already experience flooding during high tides and typhoons. A continued rise will only make these events more frequent and more destructive.

How fast are the ice sheets melting?

The international collaboration of polar scientists, headed by the European Space Agency, had in the past only looked at ice sheet melt since the 1990s based on European satellite data. But by incorporating NASA satellites, the scientists were able to chart ice sheet volumes in Antarctica back to 1979 and in Greenland back to 1972.

It showed that in the 1970s, 1980s and into the 1990s, the ice sheets were relatively stable. Then melt started happening, and it really kicked in during the 2010s, Otosaka said. The Jakobshavn glacier in Greenland is now retreating up to 164 feet a day.

“The ice sheets are melting away fast,” said study co-author Eric Rignot, an ice scientist at University of California, Irvine. “We are melting the polar regions, sea level is rising worldwide and will exacerbate the vulnerability of coastal regions.”

Is the melting accelerating?

“There is a clear trend that the ice sheets are losing more mass and it has been increasing from decade to decade, especially if you look at the ice being discharged to the ocean,” Otosaka said. “And that's quite clear that there's a link to climate change.”

The accelerating numbers seemed to pause from 2020 to 2023, but the study's authors said it more reflected short-term weather variations, not long-term trends. Otosaka said the study stopped with 2023 data, but she has looked at measurements since and found the accelerating trend has picked back up.

A lot of the stability in Antarctica was because East Antarctica had record snowfall, which compensated for the rapid melting in the less stable West Antarctic Ice Sheet, the authors said. The three-year hiatus was “just a bump in the record,” Rignot said. “The long rise is climate and the threat is crystal clear.”

Why should Filipinos worry about a collapse scenario?

The biggest changes scientists saw are in what they call dynamic processes, which are more abrupt and active than the slow steady melting from the air, and that is something prone to trigger runaway “tipping points,” Otosaka said. New York University ice scientist David Holland said that is what concerns him “because most of the ice loss is dynamical and that is exactly what you would expect in an ice sheet instability collapse scenario.”

“The 'wild cards' of Antarctic mass loss continue to pose a challenge for human management of the planet, a clear and present danger, but many decades in the future,” said University of Colorado ice scientist Ted Scambos, who was not part of the study. “We are now as a society smart enough to know the future, but not prudent enough to act upon the knowledge.”

The international team used 45 independent surveys and 27 different satellites. “The use of relatively independent methods gives me greater confidence in the result,” said Holland. “The upward trend is real.”

What can we do?

For our country, this report is a reminder that climate change is not a far-off problem. It is here, and it is affecting our coastline, our fishermen, and our farmers. We must support sustainable practices, protect our mangroves, and prepare our communities for the changes that are already underway. The science is clear. The question is whether we have the will to act.