國家地理:不再凍人的五大湖(4)

In Japan, priests at a Shinto temple have kept an almost 600-year record of when their lake freezes all the way across. Natural climate cycles emerge from that record -- dwarfed in recent decades by the human-caused warming that has gripped the planet. Merchants who used Finland's Tornio River for trade tracked the date the ice broke up each year from 1693 onward.

日本一座神道教寺廟里的僧侶們保存了一份將近600年的湖泊結(jié)冰記錄資料。自然氣候循環(huán)就是從這個記錄中得出的，但是近幾十年來，由于人類活動導(dǎo)致的全球變暖更顯著，所以這種自然氣候循環(huán)就顯得微不足道了。從1693年開始，利用芬蘭托爾尼奧河進(jìn)行貿(mào)易的商人，每年都會跟蹤冰層的破裂日期。

In Lake Superior, shipping companies have kept records of ice formation and breakup since 1857. The records show cold years with long stretches of early ice, warm years with less. But overall they are a clear signal of human-caused warming since the industrial revolution.

在蘇必利爾湖，船運公司自1857年以來一直保存著冰層形成和破裂的記錄資料。記錄顯示，寒冷的年份會有一個較長時間的早期冰期，而溫暖的年份則相對較短。但總的來說，這是工業(yè)革命以來人為因素造成的氣候變暖的明確信號。

"What's happening in the Great Lakes region is a small part of a bigger story," says Lesley Knoll. A lake expert at the University of Minnesota's Itasca Biological Station, she studies people's cultural relationships with frozen lakes.

萊斯利·諾爾表示：“五大湖地區(qū)正在發(fā)生的，只是一個大事件中的一小部分。”作為明尼蘇達(dá)大學(xué)伊塔斯卡生物站的湖泊專家，她主要負(fù)責(zé)研究人類文化與冰凍湖泊的之間關(guān)系。