经济学人下载:勿忘历史(1)

After HURRICANE BETSY pummelled New Orleans in 1965,
1965年飓风贝齐席卷新奥尔良后，

causing damage so severe that "Betsy" was retired from the rotating list of names given to Atlantic hurricanes,
造成了非常严重的破坏，以至于“贝齐”从命名大西洋飓风的轮班名单上退位，

the Governor of Louisiana, John McKeithen, pledged that nothing like it would happen in his state again.
美国路易斯安那州州长约翰·麦基森承诺本州再也不会发生类似灾害。

Exactly 40 years later Hurricane Katrina brought even greater destruction to the city,
正好40年后， 飓风卡特里娜对这个城市造成了更严重的破坏，

and hazard planners were deemed to have ignored the lessons of the past.
灾害部门被认为忽视了过去的教训。

New research suggests that far from being an exception, Louisiana's forgetfulness is the rule.
新研究表明路易斯安那州的健忘绝非例外而是常事。

Collective memory for past calamities is of more than just academic interest,
对过去灾害的集体记忆不仅仅是出于学术兴趣

precisely because resilience to future calamities is thought to depend on it.
更准确的说是因为对未来灾害的恢复力被认为取决于这种记忆。

Most research on the subject has been conducted by social scientists
关于该主题的大部分研究都由社会科学家进行，

who have tracked the durability of memories over years—at most a decade—usually by means of questionnaires.
他们通常通过调查问卷的形式对多年—最多十年—的记忆持久度进行跟踪研究。

Researchers at the Czech University of Life Sciences, in Prague, led by environmental historian Vaclav Fanta,
布拉格捷克大学生命科学系的研究人员在环境历史学家Vaclav Fanta的带领下

have approached the problem differently, investigating how memories of disasters shaped decisions over several generations.
通过调查灾难记忆如何影响几代人的决策，用不同方式理解这个问题。

In a paper published recently in Nature Communications,
近期在《Nature Communications》发表的一篇论文中，

they analysed data on almost 1,300 towns and villages in the Vltava river basin in central Europe
他们分析了中欧地区伏尔塔瓦河流域近1300个小镇和村庄的数据

—drawing both on historical records and on archaeological methods such as carbon dating—
—选取了它们的历史数据和考古方法，如碳测定年代—

and compared them with the timings of floods in that basin over the course of nearly 900 years.
并对该流域近900年间发洪水的时机进行比较。

The floods studied were defined as extreme, meaning that the river's run-off was in excess of 4,000 cubic metres per second,
该团队研究的洪水均被定义为极端灾害，这意味着该条河流的流量超过了4000立方米每秒，

or almost 30 times its normal rate. Such mega-floods occur, on average, less than once a century,
几乎是正常速度的30倍。这种特大洪水发生的平均次数为一世纪不足一次，

and the researchers recorded seven of them, the first in 1118 and the last in 1845.
研究人员记录了其中的7起，第一起是在1118年，最后一起是在1845年。

In each case, new settlements appeared a significantly higher vertical distance above the river's normal level
在每种情况下，新建定居点的垂直距离都比洪水前同片区域定居点高，

than settlements built in the same area before the flood, and continued to do so for 25 years (about a generation) after the deluge.
且高于河流的正常水位，这种情况在洪水发生后持续了25年（约一代人）。