Dinosaurs 'killed off by a sudden drop in temperature and NOT by a comet'
By Daily Mail Reporter
Last updated at 2:24 PM on 23rd April 2010
Dinosaurs were wiped off the face of the Earth by a sudden drop in temperature and not by a comet striking the planet, scientists claimed today.
恐龍在地球面上被清除，由一溫度突然下降，而不是由彗星撞擊地球，科學家今天聲稱。
Researchers studying fossils in Norway have discovered that the world's seas plummeted 9C from 13C to just 4C around 137million years ago.
研究人員在挪威研究化石已發現，世界海洋在 137million年前後從13C暴跌9C至僅僅4C。
They believe this was caused by a sudden change in the Atlantic Gulf Stream - a phenomenon many experts fear is about to happen again.
他們相信這是由大西洋灣流的突然改變導致 - 一個現象許多專家擔心會即將再次發生。
Evidence? This Jurassic ammonite discovered in Svalbard, Norway reveals the sudden drop in temperature which may have contributed to the extinction of the dinosaurs, scientists believe
證據？這侏羅紀菊石在斯瓦爾巴德群島發現，挪威揭示突然下降的溫度可能造成恐龍的滅絕，科學家相信
The temperature drop during the Cretaceous period would almost certainly have wiped out an 'abundance' of the world's dinosaurs.
在白堊紀時期的氣溫下降，幾乎肯定已清除一'大量'世界上的恐龍。
The scientists behind the ground-breaking study claim this would have been the first major step dinosaurs took on their eventual road to extinction.
在突破性研究背後的科學家聲稱，這將已是第一個重要步伐，恐龍踏上它們最終的滅絕道路。
Some experts believe the creatures were wiped out by one cataclysmic event 65million years ago - such as a meteor hitting the planet.
一些專家相信這種生物消滅，是被一個 在6,500萬年前的災難性事件 - 如流星撞擊地球。
But the new research suggests they were wiped out by a series of environmental changes - starting with a drop in sea temperatures.
但新的研究提出，他們被一系列的環境變化消滅 - 開始於海洋溫度下降。
The study was conducted by a team of scientists, led by Dr Gregory Price of Plymouth University, who examined fossils and minerals from Arctic Svalbard in Norway.
研究是由一組科學家進行，由普利茅夫大學的格雷戈里派斯博士率領，在挪威檢查從北極斯瓦爾巴德群島來的化石和礦物。
Dr Price found the drop in temperatures was so severe that numerous species of dinosaur previously living in warm, shallow seas, land and swamps would have died out.
派斯博士發現溫度下降是如此嚴重，所以許多種曾生活在溫暖、淺海、陸地和沼澤地的恐龍將已死光。
He said the team's research showed the drop in temperature happened when the Earth was in a 'greenhouse' climate - similar to now.
他說隊伍的研究顯示，溫度下降發生當地球是在一'溫室'氣候 - 類似現在。
Researchers: Dr Gregory Price and Dr Elizabeth Nunn in the Norwegian Svalbard where they made their discovery
研究人員：格雷戈里派斯博士和伊麗莎白納恩博士在挪威斯瓦爾巴特群島，在那裡他們作出發現
'The drop in temperatures may well have been caused by a change in ocean circulation, much like what is being predicted for the Gulf Stream,' he said.
'In the Cretaceous period, the Atlantic was much narrower but it would have featured a similar, northerly-flowing current.
'If it had stopped working it could have resulted in the melting of the ice caps, causing a sudden drop in temperatures.
'We believe dinosaurs were most likely to be cold-blooded creatures and would have needed the warmth to keep them alive. If they were unable to migrate south they could have been wiped out.
'Climate change is now very much on the agenda in trying to determine how the dinosaurs became extinct.
'We now believe that they died out gradually and it is very possible that this could have been caused by a series of climatic changes.'
The drop in temperature is thought to have occurred because high levels of CO2 were in the atmosphere which caused global temperatures to rise and polar ice to melt - a phenomenon currently predicted for Earth.
It is the equivalent of the predicted shut-down of the Gulf Stream 'conveyor belt' - which scientists have warned could take Europe into another ice age.
Dr Price has been visiting the Svalbard since 2005, collecting fossils and samples in an area famed for a number of palaeontological discoveries, including giant marine reptiles such as pliosaurs and icthyosaurs.
He added: 'The flourishing of the dinosaurs and a range of other data indicates that the Cretaceous period was considerably warmer and boasted a high degree of CO2 in the atmosphere.
'But over a period of a few hundred or a few thousand years, ocean temperatures fell from an average of 13 degrees centigrade to between eight and four degrees.'
http://www.dailymail.co.uk/sciencetech/article-1268305/Dinosaurs-killed-sudden-drop-temperature.html
恐龍死於氣溫驟降'而不是彗星襲擊，科學家聲稱
Dinosaurs died from sudden temperature drop 'not comet strike', scientists claim
Published: 8:00AM BST 24 Apr 2010
http://www.telegraph.co.uk/science/dinosaurs/7624014/Dinosaurs-died-from-sudden-temperature-drop-not-comet-strike-scientists-claim.html
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