2010年06月05日09:43
來源：國際在線
南太平洋小島毛琵地，海平面上升並沒有讓這些小島受到太大威脅。
據德國媒體6月3日報道，科學家曾表示，由於氣候變暖，海平面正在不斷升高，許多小島有被海水淹沒的危險。但從太平洋上空航拍的一些照片來看，這種擔心似乎有些多余。由於珊瑚的存在，雖然海水正不斷上漲，但小島們的面積卻增加了。
由於海平面上升，氣候學家長期以來一直警告稱，海島和沿海地區將被海水淹沒。在聯合國氣候大會上，還有代表稱那些島國有“亡國之憂”。之前，馬爾代夫政府也稱本國可能會因氣候變化沉入海面以下。
然而近日，學者在美國的科技期刊雜志《全球及星球變化》(Global and Planetary Change)上發表文章稱，盡管海平面在上升，但在過去60年中，很多太平洋小島的面積卻增加了。奧克蘭大學的保羅·肯奇和斐濟的地球研究學者亞瑟·韋伯通過對上世紀50年代太平洋的27個小島的航拍照片和衛星圖片與現在的資料進行對比，得出結論：隻有4個小島的面積變小了，剩下的23個面積沒變甚至變大了。曾被認為世界上最危險的島國圖瓦盧，全國沒有任何地方海拔高度超過5米，在過往這些年中，領土也由曾經的7個珊瑚島增加到現在的9個，盡管在這段歲月裡，海平面上升了0.12米。
馬紹爾群島：由於珊瑚石的堆積，很多島嶼的面積增加了，當然島內的部分沒有變化。
衛星圖片展示出驚人的結果：南太平洋小島並沒有因為海平面上升而縮小。實線表示的是今天的海岸線，虛線表示的是1984年的海岸線位置。
圖瓦盧的一座島嶼在過去60年中海岸線不斷外擴。
http://scitech.people.com.cn/BIG5/11791261.html
太平洋島嶼 '在增長而不是縮小'：由於氣候變化
Pacific islands 'growing not shrinking' due to climate change
Low-lying Pacific islands regarded as "poster child" examples of the threat from rising sea levels are expanding not sinking, a new study has revealed.
地勢低窪的太平洋島嶼被視為海平面上升威脅的“範例”，實情是正在擴大而不是下沉，一項新的研究顯示。
By Paul Chapman in Wellington
Published: 7:00AM BST 03 Jun 2010
An aerial view shows Tarawa, Kiribati, South Pacific Photo: REUTERS
空中視景顯示南太平洋基里巴斯塔拉瓦 圖片：路透社
Scientists have been surprised by the findings, which show that some islands have grown by almost one-third over the past 60 years.
科學家們已因發現而感到吃驚，它顯示一些島嶼在過去 60年已增長差不多三分之一。
Among the island chains to have increased in land area are Tuvalu and neighbouring Kiribati, both of which attracted attention at last year's Copenhagen climate summit.
在島鏈中已增加土地面積的有圖瓦盧和鄰島基里巴斯，兩者在去年哥本哈根的氣候峰會都引人注目。
In the study, researchers compared aerial photographs and high-resolution satellite images of 27 islands taken since the 1950s.
在研究中，研究人員比較自1950年代以來，27 島嶼的空中拍攝照片和高解像衛星圖像。
Only four islands, mostly uninhabited, had decreased in area despite local sea level rises of almost five inches in that time, while 23 stayed the same or grew.
只有4個島嶼已減少面積，大部分是無人居住的，儘管本地海平面那時上升近5吋，而23個島嶼保持不變或上升。
Seven islands in Tuvalu grew, one by 30 per cent, although the study did not include the most populous island.
圖瓦盧的七島增長，一個約30%，雖然研究並不包括人口最多的島嶼。
In Kiribati, the three of the most densely populated islands, Betio, Bairiki and Nanikai, also grew by between 12.5 and 30 per cent.
在基里巴斯，三個人口最稠密的島嶼，貝蒂奧，拜裡基和Nanikai，也增長約12.5%至30%之間。
Professor Paul Kench, of Auckland University, who co-authored the study with Dr Arthur Webb, a Fiji-based expert on coastal processes, said the study challenged the view that the islands were sinking as a result of global warming.
奧克蘭大學教授保羅 Kench，他與一個以斐濟為基地在海岸過程方面的專家阿瑟韋布博士共同撰寫研究，說研究挑戰那看法，全球變暖結果使島嶼下沉。
"Eighty per cent of the islands we've looked at have either remained about the same or, in fact, got larger.
“百分之八十的島嶼我們已查看的，一係保持大致相同，或事實上，變得更大。
"Some have got dramatically larger," he said.
“有些已變得顯著擴大，”他說。
"We've now got evidence the physical foundations of these islands will still be there in 100 years," he told New Scientist magazine.
我們現在有證據，這些島嶼的實質基礎，在100年內將仍然在那裡，”他告訴新科學家雜誌。
He said the study suggested the islands had a natural ability to respond to rising seas by accumulating coral debris from the outlying reefs that surround them.
"It has long been thought that as the sea level goes up, islands will sit there and drown. But they won't," Professor Kench said.
The trend is largely explained by the fact that the islands comprise mostly coral debris eroded from encircling reefs, which is pushed up on to the islands by wind and waves.
Because coral is a living organism, it continues to grow and establish itself in its new home, so the process becomes continuous.
Land reclamation and deposition of other sediment also contribute to the process.
"These islands are so low lying that in extreme events waves crash straight over the top of them," Professor Kench said.
"In doing that they transport sediment from the beach or adjacent reef platform and they throw it on to the top of the island."
But the two scientists warn that people living on the islands still face serious challenges from climate change, particularly if the pace of sea level rises were to overtake that of sediment build-up.
The fresh groundwater that sustains villagers and their crops could be destroyed.
"The land may be there but will they still be able to support human habitation?" he said.
Naomi Thirobaux, a student from Kiribati who has studied the islands for a PhD, said no one should be lulled into thinking erosion and inundation were not taking their toll on the islands.
"In a populated place, people can't move back or inland because there's hardly any place to move into, so that's quite dramatic," she said.
http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/tuvalu/7799503/Pacific-islands-growing-not-shrinking-due-to-climate-change.html
低窪的太平洋島嶼'在增長而不是下沉' 當海平面上升
Low-lying Pacific islands 'growing NOT sinking' as sea levels rise
By Daily Mail Reporter
Last updated at 12:43 AM on 4th June 2010
The island nation of Tuvalu which has been threatened by rising sea levels
島國圖瓦盧一直受到海平面上升威脅
Low-lying islands in the Pacific are 'growing' to counter rising sea levels, a study has found.
Scientists feared that many small islands would disappear under rising sea levels caused by climate change.
But researchers in New Zealand measured 27 islands where ocean levels have risen 4.8 inches in the past 60 years and found that just four had diminished in size.
Coral debris eroded from encircling reefs was pushed up on to the islands' coasts by winds and waves as weather patterns changed.
Professor Paul Kench, of Auckland University's environment school, said this showed that islands are coping with the changes.
He said: 'It has been thought that as the sea level goes up, islands will sit there and drown. But they won't. The sea level will go up and the island will start responding.
'They've always changed, but the consistency [with which] some of them have grown is a little surprising.'
Tuvalu, a coral-island group that climate change campaigners have predicted will be drowned, has its highest point just 14 feet above sea level but has actually grown in the past 60 years, the study in New Scientist found.
The research, which appeared in this week's New Scientist, found that seven of Tuvalu's nine islands had grown by more than 3 percent on average over the past 60 years.
In 1972, Cyclone Bebe dumped 346 acres of sediment on the eastern reef of Tuvalu, increasing the area of Funafuti, the main island, by 10 percent.
Another island, Funamanu, gained nearly 30 percent of its previous area.
On World Environment Day in 2008, Kiribati President Anote Tong warned parts of his island nation were already being submerged, forcing some of Kiribati's 94,000 people living in shoreline village communities to be relocated from century-old sites.
Worst case scenarios showed Kiribati would disappear into the sea within a century, he said at the time.
Professor Kench added: 'In other words, they (the islands) are slowly moving ... migrating across their reef platforms.'
'As the sea-level conditions and wave conditions are changing, the islands are adjusting to that.'
But he warned an accelerated rate of sea-level rise could be 'the critical environmental threat to the small island nations,' with 'a very rapid rate of island destruction' possible from a water depth beyond a certain threshold. That threshold currently is unknown.
Australian sea level oceanographer John Hunter said the findings 'are good news and not a surprise.'
'Coral islands can keep up with some sea-level rise, but (there's also) ocean warming ... and ocean acidification ... that are certainly problematic for the corals.
'Sea-level rise can actually make the islands grow - as it apparently is doing,' said Hunter.
http://www.dailymail.co.uk/sciencetech/article-1283669/Low-lying-Pacific-islands-growing-sinking-sea-levels-rise.html
編者的話：太平洋島嶼不因全球變暖下沉
EDITORIAL: Pacific islands not sinking from global warming
New study debunks Al Gore's hysterical fairy tale
新研究踢爆戈爾的歇斯底里童話
7:14 p.m., Friday, June 11, 2010
http://www.washingtontimes.com/news/2010/jun/11/pacific-islands-not-sinking-from-global-warming/
衛星照片顯示：北極海冰短期內不減反增
海平門：海平面在過去50多年並沒有上升
Disc:
http://www.discuss.com.hk/viewthread.php?tid=12354392&page=1&extra=page%3D1#pid253673485
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