原文網址：https://phys.org/news/2025-03-sea-ice-age-revealed-geological.html
距今11700年前末次冰期結束之後，全球海平面也隨之上升。新的地質數據讓科學家對於上升過程的速率與規模得到了更多見解，這些資訊在了解全球暖化對冰層以及海平面上升會有什麼影響的時候相當重要。
全球海平面會在未來100年快速上升，幅度可能超過1公尺。原因主要是溫室氣體的濃度增加(來源：IPCC)。北海地區的水下煤層顯示過去曾經有兩段時期也能看到此種速率：分別是在10,300年前與8,300年前。當時的冰層融化是末次冰期結束之後的快速暖化所導致。圖片來源：Deltares
這項發現最近發表於期刊《自然》(Nature)，作者為三角洲學院、烏特勒支大學、荷蘭應用科學研究院( TNO)的荷蘭地質調查機構、台夫特理工大學、荷蘭海洋研究所、里茲大學、雪菲爾大學、阿姆斯特丹大學、萊布尼茲應用地球物理研究所、德國聯邦地球科學與自然資源研究院的研究人員。
深入了解海平面上升
這份關於全新世早期海平面上升速率的新知識，對於科學家與決策者來說是很重要的參考點，尤其考量到全球暖化造成冰層快速融化使得我們正面臨類似的情境。此研究讓我們對於未來有了相當貴重的全新見解。
依照當前的溫室氣體濃度上升速率，政府間氣候變化專門委員會的氣候模型預估到了2300年海平面將上升好幾公尺，在某些情境下每個世紀甚至會上升一公尺以上。發生在全新世早期與現在及未來的海平面上升，一個重要的差別在於後者會造成嚴重許多的後果，原因得歸咎於人口的大量成長，以及現代才有的建設、城市與經濟活動。
北海區域的獨特數據
全球海平面隨著末次冰期結束而快速上升，這是因為全球暖化以及覆蓋北美與歐陸的巨大冰帽融化所導致。目前為止由於缺乏堅實的全新世早期地質數據，使得這段時間海平面的上升速率程度還尚未明瞭。
利用北海區域得到的獨特數據，研究人員最近首度計算出極為精準的結果。他們分析了一系列的鑽井數據，其位於北海稱為「多格蘭」的區域，這裡曾是連接英國與歐陸的陸橋，隨著海平面上升而沉沒在水底。
分析此區域的水下煤層，加以定年並運用電腦模擬的技術，研究人員顯示全新世早期有兩個階段的海平面上升速率的峰值曾經短暫地超過每個世紀一公尺。相較之下，目前荷蘭的海平面上升速率大概為每年3
mm，相當於每個世紀30公分，預估還會繼續增加。
除此之外，在此之前對於距今11,000年至3,000年前的海平面總上升值有很大的不確定性，過往的估計值從32到55公尺不等。新的研究排除了這些不確定性，顯示總上升值大約為38公尺。
三角洲學院的地質學家Marc
Hijma是研究主要作者，他說：「有了這項突破性的研究成果，我們對於更加了解末次冰期結束之後的海平面上升踏出了相當重要的一步。藉由詳細繪製出北海地區的數據，我們現在可以更加釐清冰層、氣候與海平面之間的複雜關係。」
「科學家與決策者都能從此得到更多見解，使得我們能對當前的氣候變遷做出更好的應對，比方說要更著重氣候調適。」
Sea level rise
after the last ice age revealed by new geological data
New geological data has given more
insight into the rate and magnitude of global sea level rise following the last
ice age, about 11,700 years ago. This information is of great importance to
understand the impact global warming has had on the ice caps and on sea level
rise.
The findings have been published in the journal Nature by researchers from Deltares,
Utrecht University, TNO Netherlands Geological Service, Delft University of
Technology, the Netherlands Institute for Sea Research (NIOZ), University of
Leeds, University of Sheffield, University of Amsterdam, LIAG and BGR.
Better
understanding of sea level rise
The new knowledge of the rate of sea level rise
during the early Holocene offers an important point of reference for scientists
and policymakers, especially as we are now faced with a similar situation with
rapidly melting ice sheets due to global warming. The research provides
valuable new insights for the future.
As a result of the current rise in greenhouse gas
concentrations, climate models by the Intergovernmental Panel on Climate Change
(IPCC) expect sea levels to rise by several meters by 2300. Some scenarios
indicate a rise of more than 1 meter per century. An important difference with
the early Holocene is that the consequences of sea level rise are far greater
today and in the future. This is due to a growth in population and the current
presence of infrastructure, cities and economic activity.
Unique dataset in
the North Sea region
Global sea level rose quickly following the last ice
age. This was as a result of global warming and the melting of enormous ice
caps that covered North America and Europe. Until now, the rate and extent of
sea level rise during the early Holocene were not known due to a lack of sound
geological data from this period.
Using a unique dataset for the North Sea region, the
researchers have now been able to make highly accurate calculations for the
first time. They analyzed a range of boreholes from the area in the North Sea
that was once Doggerland, a land bridge between Great Britain and mainland
Europe. This area flooded as sea level rose.
By analyzing the submerged peat layers from this
area, dating them and applying modeling techniques, researchers showed that,
during two phases in the early Holocene, rates of global sea level rise briefly
peaked at more than a meter per century. By comparison, the current rate of sea
level rise in the Netherlands is about 3 mm annually, the equivalent of 30
centimeters per century, and is expected to increase.
Furthermore, until now there has been considerable
uncertainty about the total rise between 11,000 and 3,000 years ago. Estimates
varied between 32 and 55 meters. The new study has eliminated that uncertainty
and it shows that the total rise was about 38 meters.
Marc Hijma, a geologist at Deltares and the lead
author of the study, says, "With this groundbreaking research, we have
taken an important step towards a better understanding of sea level rise after
the last ice age. By drawing on detailed data for the North Sea region, we can
now better unravel the complex interaction between ice sheets, climate, and sea
level.
"This provides insights for both scientists and
policymakers, so that we can prepare better for the impacts of current climate
change, for example by focusing on climate adaptation."
原始論文：Marc
P. Hijma, Sarah L. Bradley, Kim M. Cohen, Wouter van der Wal, Natasha L. M.
Barlow, Bas Blank, Manfred Frechen, Rick Hennekam, Sytze van Heteren, Patrick
Kiden, Antonis Mavritsakis, Bart M. L. Meijninger, Gert-Jan Reichart, Lutz
Reinhardt, Kenneth F. Rijsdijk, Annemiek Vink, Freek S. Busschers. Global sea-level rise in the early Holocene
revealed from North Sea peats. Nature,
2025; 639 DOI: 10.1038/s41586-025-08769-7
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