Arctic sea ice, a key component of Earth’s natural thermostat, has thinned sharply in recent years, with the northern polar ice cap shrinking steadily in surface area, government scientists said on Monday.
Thinner seasonal sea ice, which melts in the summer and freezes in the fall, now accounts for about 70 percent of the total in the Arctic, up from 40 percent to 50 percent in the 1980s and 1990s, the researchers said, citing new satellite data.
At the same time, thicker ice, which lasts two summers or more without melting, now comprises less than 10 percent of the northern polar ice cap in winter, down from 30 to 40 percent. Just two years ago, the thicker, so-called perennial sea ice made up 20 percent or more of the winter cap.
Scientists have voiced concerns for years about an alarming decline in the size of the Arctic ice cap, which functions as a giant air conditioner for the planet’s climate system by reflecting sunlight into space.
As a greater portion of the ice melts, it is replaced by darker sea water that absorbs much more sunlight, thus adding to the warming of the planet attributed to rising levels of greenhouse gases emitted into the atmosphere by human activity.
“The ice cover plays a key role in the climate,” Thomas Wagner, chief snow and ice scientist for NASA, said in a conference call with reporters. “The thicker ice particularly is very important, because it’s the thicker ice that survives the summer to stay around and reflect that summer sunlight.”
Walter Meir of the National Snow and Ice Data Center in Boulder, Colorado, said: “We’re getting an ice cover as we finish the winter and head into summer that’s much more vulnerable to the summer melt and much more likely to melt completely and expose that dark ocean.”
The decade-long trend of a contracting ice cap around the North Pole is continuing as well.
The maximum extent of Arctic sea ice this winter was measured at 15.2 million square kilometers, the fifth-lowest winter peak on record. That tally represents a loss of some 720,000km² — about the size of Texas — from the winter peak average between 1979 and 2000.
The six lowest measurements since satellite monitoring began in 1979 have all occurred in the past six years.
Meir said a strong consensus has emerged among climate scientists that the Arctic is headed for its first largely ice-free summer in the relatively near future, with forecasts running as early as 2013, though he sees that as too soon.
PATROL PARTNERS: The ‘Chiayi’ and the ‘Penghu’ departed for a two-day joint patrol of Palau’s exclusive economic zone, the CGA’s second diplomatic visit to the country The Coast Guard Administration (CGA) set a record for its southernmost deployment of a coast guard vessel as the vessels Chiayi and the Penghu reached Palau’s Pulo Anna Island on Saturday in a cooperative exercise between the two countries. The island, about 217 nautical miles (401km) southwest of Koror in the Palauan state of Sonsorol and 1,220 nautical miles from Taiwan’s southernmost point, Oluanpi (鵝鑾鼻), is the furthest south a CGA vessel has sailed. The two vessels are in Palau for the coast guard’s second diplomatic visit to the country. They docked at Malakal Harbor on Tuesday last week. The coast guard
BATCH 1: The military has plans to assign the weapons to the army to defend Taiwan proper, as well as outlying islands and the navy for the Marine Corps, the official said Taiwan is to receive 500 Stinger missiles and 178 launchers from the US by the end of the year, the first batch under a planned two-stage acquisition totaling 2,621 missiles and 763 launchers, a defense official said yesterday on condition of anonymity. The portable missiles would play a vital role in the nation’s air defense capabilities, the source said. The army plans to deploy 2,235 missiles and 657 launchers to defend Taiwan proper and outlying islands, they said, citing military documents. The navy is allotted 295 missiles and 85 launchers to arm the Marine Corps and some surface vessels that lack air defense
The government is monitoring online rumors that a pneumonic plague outbreak has spread from Russia into China, and it might enhance quarantine measures, Premier Cho Jung-tai (卓榮泰) said yesterday. During a legislative meeting, Democratic Progressive Party Legislator Wang Ting-yu (王定宇) said that rumors had circulated that the disease had spread across several Chinese provinces. He asked Cho whether the government was prepared to prevent the disease spreading to Taiwan, given the volume of traffic between the two sides, and how concerned the government was about the alleged outbreak. The Ministry of Health and Welfare had implemented border quarantine measures after briefing the Executive
The European Parliament on Wednesday adopted a recommendation on EU-China political relations that rejected China’s efforts to restrict Taiwan’s participation in international organizations and exchanges. The recommendation, addressed to the European Council, the European Commission and EU High Representative for Foreign Affairs and Security Policy Kaja Kallas, includes several references to EU-Taiwan relations and expresses support for closer ties, saying they would bring positive benefits and have strategic importance. Describing Taiwan as a valuable partner in trade and technology, the European Parliament said it “rejects China’s attempts to coerce international organizations, third countries and other actors into restricting Taiwan’s international participation and
RSS