El Nino
While some forecasting methods had limited success predicting the 1997 El Nino a few months in advance1, the Columbia University researchers say their method can predict large El Nino events up to two years in advance. That would be good news for governments, farmers and others seeking to plan for the droughts and heavy rainfall that El Nino can produce in various parts of the world.
Using a computer, the researchers matched sea-surface temperatures to later El Nino occurrences between 1980 and 2000 and were then able to anticipate El Nino events dating back to 1857, using prior sea-surface temperatures. The results were reported in the latest issue of the journal Nature.
The researchers say their method is not perfect, but Bryan C Weare, a meteorologist at the University of California, Davis, who was not involved in the work, said it suggests2 El Nino is indeed predictable.
This will probably convince others to search around more for even better methods, said Weare. He added that the new method makes it possible to predict El Nino at long lead times3. Other models also use sea-surface temperatures, but they have not looked as far back because they need other data, which is only available for recent decades, Weare said.
The ability to predict the wanning and cooling of the Pacific is of immense importance4. The 1997 El Nino, for example, caused an estimated $20 billion in damage worldwide, offset by beneficial effects in other areas, said David Anderson, of the European Centre for Medium-Range Weather Forecasts in Reading, England. The 1877 El Nino, meanwhile, coincided with a failure of the Indian monsoon and a famine that killed perhaps 40 million in India and China, prompting the development of seasonal forecasting, Anderson said.
When El Nino hit in 1991 and 1997, 200 million people were affected by flooding in China alone, according to a 2002 United Nations report.
While predicting smaller El Nino events remains tricky, the ability to predict larger ones should be increased to at least a year if the new method is confirmed.
El Nino tends to develop between April and June and reaches its peak between December and February. The warming tends to last between 9 and 12 months and occurs every two to seven years.
The new forecasting method does not predict any major El Nino events in the next two years, although a weak warming toward the end of this year is possible.
词汇:
El Nino n.厄尔尼诺现象
equatorial adj.赤道的
occurrence n.发生
meteorologist n.气象学家
offset v.抵消
lead adj.领先的
monsoon n.季风
tricky adj.难以捉摸的
注释:
1. methods had limited success predicting predicting the 1997 El Nino a few months in success的含义。
2.suggests:suggest在文中的意思是表明,显示出。
3.at long lead times:lead的意思相当于in advance。at long lead times的意思是在领先很长的一段时间里。
4.of immense importance = immensely important
练习:
1.The method used by the Columbia University researchers can predict El Nino a few months in advance.
A Right B Wrong C Not mentioned
2.The Columbia University researchers studied the relationship between the past El Nino occurrences and sea-surface temperatures.
A Right B Wrong C Not mentioned
3.The Columbia University researchers are the first to use sea-surface temperatures to match the past El Nino occurrences.
A Right B Wrong C Not mentioned
4.Weares contribution in predicting El Nino was highly praised by other meteorologists.
A Right B Wrong C Not mentioned
5.According to a Chinese report, the flooding in China caused by El Nino in 1991 and 1997 affected 200 million Chinese people.
A Right B Wrong C Not mentioned
6.It takes about eight months for El Nino to reach its peak.
A Right B Wrong C Not mentioned
7.A special institute has been set up in America to study El Nino.
A Right B Wrong C Not mentioned
答案与题解:
1.B文章第一段第一句说,哥伦比亚大学的方法can predict large El Nino events up to two years in advance,而不是几个月。
2.A本题给出的信息是正确的,根据是第二段的第一句。
3.C第四段说到其他一些预测El Nino的方法也有涉及sea-surface temperatures这一因素的,但是文章没有提到是谁首先用sea-surface temperatures测定法预测El Nino的。
4.C文章中提到Weare的地方是第三段、第四段,但都没有说到气象学家髙度评价Weare在预测El Nino方面做出的贡献。
5.B第六段说到,关于中国受灾的数据是根据一份2002年的United Nations report作出的。
6.A第八段说,El Nino一般开始于4月与6月之间,到12月与2月之间达到高峰,从发生到高峰经历的时间约为8个月。
7.C通篇文章没有提到美国成立了一个El Nino研究所。
译文:厄尔尼诺
当某些预报方法不能提前几个月成功预测 1997年厄尔尼诺现象的时候,哥伦比亚大学的研究人员说他们的方法可以提前两年预测厄尔尼诺现象。这对全世界各地的政府、农民和其他寻求为厄尔尼诺带来的干旱和大雨做准备的人来说是一条好消息。
研究人员使用计算机把 1980年初 2000年之间的海面温度和后来的厄尔尼诺的发生联系起来,进而能够用之前的海面温度预测远至 1857年的厄尔尼诺现象。研究结果刊登在最新的《自然》杂志上。
研究人员说他们的方法并不完美,但加利福尼亚大学的气象学家 Bryan C.Weare说这种方法显示出厄尔尼诺是可以预测的,尽管他们已并没有参加研究工作。
Weare说:这会促使其他人去寻找里好的办法。他还补充说,新的方法使在提前很长的一段时间里预测厄尔尼诺现象成为可能。 其他的方法也使用海面温度,但他们没能回顾得那么久远是因为缺少其他的资料,而这些资料在近几十年才能够获得。
预测太平洋的升温和降温有极其重要的意义。英国 Reading的欧洲中级天气预报中心的 David Anderson说:以 1997年的厄尔尼诺为例,它导致了全球范围内约 200亿美元的损失,抵消了在其他一些地区的良性影响; 1877年的厄尔尼诺与印度遭受的季风和饥荒同时发生,导致了印度和中国约四千万人丧生,结果剌激了季节性预报的发展。
根据 2002年的联合国报道, 1991年初和 1997年厄尔尼诺爆发的时候,仅中国就有 2亿人受到洪水的侵害。
然而小的厄尔尼诺预测还是难以捉摸的,如果新的方法被认可的话,对大型厄尔尼诺现象的预测至少应该被提前一年。
厄尔尼诺总是在 4月和 6月期间发展,在 12月初 2月之间达到高峰。气候总是在 9月初 12月之间变暖,并且每 2年到 7年出现一次。
尽管气温在年底的时候有可能微弱上升,新的预测方法预计未来两年不会出现大的厄尔尼诺现象。