Volcanic Eruption Linked to Green TidesA huge plankton bloom in the North Pacific is traced to a volcanic eruption and offers a test in iron fertilization.
在北太平洋的一個巨大浮游生物繁盛期，被追溯到一次火山噴發，並提供鐵施肥試驗。
By Larry O'Hanlon
Tue Oct 12, 2010 11:00 PM ET
Translationm by Autumnson Blog
Phytoplankton from the subarctic Pacific. The plankton was among a large and unusual plankton bloom that resulted from a volcanic eruption. Click to enlarge this image.Angelica Peña, Fisheries and Oceans Canada
來自亞北極太平洋的浮游植物。浮游生物是其中一個大而不尋常的浮游生物繁盛期，由火山噴發造成的。點擊放大這圖片。
當歸佩尼亞，加拿大漁業和海洋
A large and very unusual plankton bloom in the North Pacific has been tracked, whodunnit style, to the eruption of a remote volcano in the Aleutian Islands. The volcano-plankton connection is the iron-rich volcanic ash that was launched out of the Kasatochi volcano and then rained down into the ocean.
在北太平洋的一個大而非常不尋常的浮游生物盛期已被追踪，whodunnit風格，對阿留申群島的一個遠程火山噴發。該火山浮游生物關係是含鐵豐富的火山灰，被Kasatochi火山射出和然後如雨下到海洋。
"People have hypothesized about it in the past," said researcher Roberta Hamme of the University of Victoria, regarding the possibility that volcanoes can have such an effect on iron-poor seas. "This the first time we have observed it."
“人們已在過去假設它，”維多利亞大學研究員羅伯塔哈梅說，認為火山在缺鐵的海洋可以有這樣的影響的可能性。 “這是第一次我們觀察到它。”
Hamme is the lead author on a paper in Geophysical Research Letters which shows how data from two spacecraft, two research ships, buoys and a robotic ocean glider all came together serendipitously to implicate the volcano well after the event had occurred in the summer of 2008.
She and a diverse group other researchers had found signs of the unprecedented bloom, but it wasn't until they all started talking to one another at a meeting that they discovered they had encountered something in common affecting one to two million square kilometers of ocean.
That's what got Hamme looking at the satellite images of volcanic ash Aleutian eruptions. The Kasatochi volcano stood out because it was timed right and had a wide plume of ash which covered the vast area of the plankton bloom.
"I hadn't put any credence in it until we eliminated the other possibilities," Hamme told Discovery News.
The same sort of plume was not seen in the North Atlantic from the recent Icelandic volcanics, says Hamme, because those waters are not iron deficient. In the north Pacific, just about everything is present for plankton to thrive except iron. So all it takes is a jolt of iron to start a plankton explosion.
The discovery also provides scientists with data on the largest case of ocean iron fertilization ever measured. According to the field measurements, the bloom sucked up 0.01 petagrams of carbon (10 million metric tons). That's just half of one percent of how much carbon the oceans take up all year and an even smaller fraction of the 6.5 petagrams or so of carbon humans release into the atmosphere by burning fossil fuels.
Hamme and her colleagues compared the carbon uptake to that of a deliberate iron fertilization experiment done in the same part of the ocean called in 2002. The Subarctic Ecosystem Response to Iron Enrichment Study (SERIES) managed to get plankton revved up over 1,000 square kilometers of ocean.
"Certainly the take home message is that the purposeful experiment had never been able to get greater than 1,000 square kilometers," said Philip Boyd of the National Institute of Water and Atmospheric Research, University of Otago in Dunedin, New Zealand. Boyd was a key scientist in the SERIES experiment.
"It's a pretty big kahuna," said Boyd regarding the accidental experiment created by the volcanic eruptions. Yet the amount of carbon update, as in the smaller deliberate experiments, is not impressive. "It's a pretty valuable study and certainly I'll be talking about it," said Boyd.
Despite this, there are some geoengineering people who will likely ignore the study, said Boyd, and continue trying to sell iron fertilization as a way to sequester atmospheric carbon.
"If I were a geoengineer and had a couple of venture capital people on the line I'd direct them elsewhere," Boyd said.
http://news.discovery.com/earth/volcanic-eruption-linked-green-tides-plankton.html
蟾蜍可在5天前預知地震發生
維多利亞河神秘地變成瑩光綠色
印尼Cangkringan火山爆發發送熔岩和氣體
許多'休眠'火山可能隨時爆發
日本鹿兒島櫻島火山大地震同日晚上噴發
美國夏威夷、危地馬拉火山開始噴發
印尼計劃利用野生動物作為地震和海嘯預警工具
沒有留言:
發佈留言