Shattered thresholds

The Philippines is grappling with a sea level rise that’s triple the global average, experts said at the 11th International Weather and Climate Forum in Paris. Average sea levels here rose 60 centimeters, wrote Liza Cruz of News 5. The global average, since 1900, has peaked at 19 centimeters.

Key glaciers in West Antarctica, meanwhile, are in “irreversible retreat,” reports a US National Aeronautics and Space Administration (Nasa) study. Warming ocean water is eroding the glaciers’ fronts and sea bed in a “runaway process.” That’d result in a four-foot (1.2-meter) global sea level rise.

“A threshold had been crossed,” notes Dr. Tom Wagner of Nasa. The results were not crunched out by computer simulations or numerical models. They are based on interpretation of observations. “This is important. Sometimes it can get lost on the general public when they’re trying to understand climate change and implications.”

These will impact the Philippines, warns Dr. Wendy Clavano of Environmental Science for Social Change. Using a vulnerability index that factors in erosion rates to wave lengths, Clavano foresees that rising sea levels will be highest along the Pacific seaboard. That slices from Samar to eastern Mindanao, the Zamboangas, plus the provinces of Romblon and Marinduque in the Sibuyan Sea.

Very high risk areas include the coasts of La Union and Pangasinan, fronting Lingayen Gulf, Lamon Bay in Quezon and Camarines Norte, and Camotes Sea off western Leyte. Also threatened are northern Bohol and northeastern Cebu, Guimaras Strait, along northwestern Negros Occidental, plus Cuyo in the central Sulu Sea and Iligan Bay that abuts Misamis Occidental. Add to that northern Zamboanga del Norte, and Bislig Bay, Surigao del Sur.

Rising sea levels clamp a hefty economic bill. By 2100, the mean cost of climate change for Indonesia, the Philippines, Thailand and Vietnam could be equivalent to losing 6.7 percent of combined GDP each year, says the Asian Development Bank. “That’s more than twice the global average loss.”

“The things happening to my country and to other [nations] are not in the norm,” President Aquino said in an interview with Development Asia, an ADB publication. “Increasingly powerful storms seem to be the new norm.” “Building back better” ranges from empowering local governments to be the “first responders” as the national government seeks to reinforce its emergency capacity, so when—not if—the next disaster strikes, it should find a resilient nation.

The continued melting of the West Antarctica ice sheet, however, appears unstoppable, caution two scientific papers published on May 5 by the journals Science and Geophysical Research Letters.

The University of Washington’s Ian Joughin wrote one of the reports. Using computer models and measurements of ice flow in the Thwaites glacier, the team concludes: Even if the warmer oceans, now eroding the ice, dissipate, it’d be “too little, too late… There’s no stabilization mechanism.”

The melting of the ice has “passed the point of no return,” says Eric Rignot, a glaciologist at the University of California, Irvine, in the other study. There are no mountains to slow down the retreat.

“The only thing more frightening than what science learned about climate change is the unanticipated consequences that we have yet to learn,” the New York Times noted in publishing the two reports.

Both studies fulfill a 1978 prediction by John Mercer of Ohio State University that “rapid human-driven release of greenhouse gases” would wreck the West Antarctica ice sheet. Many scoffed at Mercer then. “But in recent years, scientists confirm that events unfolded in ways Mercer predicted.” He died in 1987, spared the pain of seeing his nightmares come true.

Pennsylvania State University’s Richard Alley, who was not involved in the two studies, found them “compelling.” He had long kept a wary eye on changes affecting the Greenland ice sheet. “It shook me a little bit,” he said. There is potentially enough sea level rise that “many of the world’s coastal cities would have to be abandoned.”

Sea level rise is a “major force” against which countries like the Philippines can do little, said Michael Williams of the World Meteorological Organization. But “there’s a lot to be done with disaster risk prevention, alert systems.”

Buckle up for continuing risks, added Jean-Pascal van Ypersele, vice chair of the Intergovernmental Panel on Climate Change. “Drastically change the way structures are built in coastal areas that resist better in very high winds, very strong rain. That increases resilience.”

Are the traditional bahay  kubo, with  nipa  roofs and  sawali  walls, obsolete? Or will more just be flattened when the next stronger typhoons lash? Read the journal Nature Thursday. It published a new study by three Massachusetts Institute of Technology professors.

Kerry Emmanuel, James Kossin and Gabriel Vecchi say that tropical storms, between 1982 and 2012, surged poleward: three miles per decade in the Northern Hemisphere and 38 miles per decade in the Southern Hemisphere.

The tropics now sprawl over a larger area. That jacks up ingredients required for hurricanes to flourish. “The latitudes at which these storms reach maximum intensity seems to be increasing over time. This poleward jog is the first ‘robust’ signal that the buildup of greenhouse gases from human activity is influencing tropical storms,” the authors add. “The trend is statistically significant at a pretty high level.”

Shattered thresholds from rising seas deserve greater attention. Too many here are hyperventilating over the three (or four?) versions of Janet Lim Napoles’ testimony on the pork scam.

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E-mail: juanlmercado@gmail.com

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