The world’s oceans have warmed 50 percent faster over the last 40 years than previously thought due to climate change, Australian and US climate researchers reported on Wednesday.
Higher ocean temperatures expand the volume of water, contributing to a rise in sea levels that is submerging small island nations and threatening to wreak havoc in low-lying, densely populated delta regions around the globe.
The study, which was published in the British journal Nature, adds to a growing scientific chorus of warnings about the pace and consequences rising oceans.
It also serves as a corrective to a massive report issued last year by the Nobel-winning UN Intergovernmental Panel on Climate Change (IPCC), the authors said.
Rising sea levels are driven by two things: the thermal expansion of sea water, and additional water from melting sources of ice. Both processes are caused by global warming.
The ice sheet that sits atop Greenland, for example, contains enough water to raise world ocean levels by 7m, which would bury sea-level cities from Dhaka to Shanghai.
Trying to figure out how much each of these factors contributes to rising sea levels is critically important to understanding climate change, and forecasting future temperature rises, scientists say.
But up to now, there has been a perplexing gap between the projections of computer-based climate models, and the observations of scientists gathering data from the oceans.
“The numbers didn’t add up,” said Peter Geckler, a coauthor of the study and a researcher at the Program for Climate Model Diagnosis and Intercomparison at the Lawrence Livermore Laboratory in California.
“When previous investigators tried to add up all the estimated contributions to sea level rise” — thermal expansion, melting glaciers, ice caps and ice sheets, along with changes in terrestrial storage — “they did not match with the independently estimated total sea level rise,” he said.
The new study, led by Catia Domingues of the Centre for Australian Weather and Climate Research, is the first to reconcile the models with observed data.
Using new techniques to assess ocean temperatures to a depth of 700m from 1961 to 2003, the study shows that thermal warming contributed to a 0.53mm-per-year rise in sea levels rather than the 0.32mm rise reported by the IPCC.
“Our results are important for the climate modeling community because they boost confidence in the climate models used for projections of global sea-level rise resulting for the accumulation of heat in the oceans,” Domingues said in a statement.
“The projections will in turn assist in planning to minimize impacts, and in developing adaptation strategies,” she said.
The IPCC report was strongly criticized for including only the impact of thermal expansion in its projections of sea level rises over the next century, despite recent studies showing that melting ice is a significant — and growing — factor.
The planet’s oceans store more than 90 percent of the heat in the Earth’s climate system.
The oceans also act as a temporary buffer against the effects of climate change.
CONFRONTATION: The water cannon attack was the second this month on the Philippine supply boat ‘Unaizah May 4,’ after an incident on March 5 The China Coast Guard yesterday morning blocked a Philippine supply vessel and damaged it with water cannons near a reef off the Southeast Asian country, the Philippines said. The Philippine military released video of what it said was a nearly hour-long attack off the Second Thomas Shoal (Renai Shoal, 仁愛暗沙) in the contested South China Sea, where Chinese ships have unleashed water cannons and collided with Philippine vessels in similar standoffs in the past few months. The China Coast Guard and other vessels “once again harassed, blocked, deployed water cannons, and executed dangerous maneuvers” against a routine rotation and resupply mission to
GLOBAL COMBAT AIR PROGRAM: The potential purchasers would be limited to the 15 nations with which Tokyo has signed defense partnership and equipment transfer deals Japan’s Cabinet yesterday approved a plan to sell future next-generation fighter jets that it is developing with the UK and Italy to other nations, in the latest move away from the country’s post-World War II pacifist principles. The contentious decision to allow international arms sales is expected to help secure Japan’s role in the joint fighter jet project, and is part of a move to build up the Japanese arms industry and bolster its role in global security. The Cabinet also endorsed a revision to Japan’s arms equipment and technology transfer guidelines to allow coproduced lethal weapons to be sold to nations
Thousands of devotees, some in a state of trance, gathered at a Buddhist temple on the outskirts of Bangkok renowned for sacred tattoos known as Sak Yant, paying their respects to a revered monk who mastered the practice and seeking purification. The gathering at Wat Bang Phra Buddhist temple is part of a Thai Wai Khru ritual in which devotees pay homage to Luang Phor Pern, the temple’s formal abbot, who died in 2002. He had a reputation for refining and popularizing the temple’s Sak Yant tattoo style. The idea that tattoos confer magical powers has existed in many parts of Asia
ON ALERT: A Russian cruise missile crossed into Polish airspace for about 40 seconds, the Polish military said, adding that it is constantly monitoring the war to protect its airspace Ukraine’s capital, Kyiv, and the western region of Lviv early yesterday came under a “massive” Russian air attack, officials said, while a Russian cruise missile breached Polish airspace, the Polish military said. Russia and Ukraine have been engaged in a series of deadly aerial attacks, with yesterday’s strikes coming a day after the Russian military said it had seized the Ukrainian village of Ivanivske, west of Bakhmut. A militant attack on a Moscow concert hall on Friday that killed at least 133 people also became a new flash point between the two archrivals. “Explosions in the capital. Air defense is working. Do not