This is the VOA Special English Technology Report.
这里是美国之音慢速英语科技报道。
A powerful earthquake struck the northeastern coast of Japan at two forty-six p.m. local time on March eleventh. Japan's Meteorological Agency released its first tsunami warnings just three minutes later. The country has one of the best earthquake early warning systems in the world.
当地时间3月11日下午2点46分，一次强烈地震袭击了日本东北部海岸。仅仅3分钟后，日本气象厅就发布了首次海啸预警。日本拥有全球最先进的地震早期预警系统。
There are more than four thousand Seismic Intensity Meters in place throughout Japan to measure earthquake activity. These meters provide information within two minutes of an earthquake happening. Information about the strength and the center of the earthquake can be learned within three minutes.
超过4千个地震烈度测量仪器遍布日本，用于测量地震活动。这些仪器能在地震发生2分钟内提供相关信息，3分钟内就能获得有关地震强度和震中的信息。
There are also concrete sea walls around much of the Japanese coastline. But these measures proved no match for the powerful earthquake and tsunami.
日本大部分海岸沿线都修建了水泥防波堤，但这些措施被证明无法抵御如此强烈的地震和海啸。
Costas Synolakis is a tsunami expert with the Department of Civil and Environmental Engineering at the University of Southern California in Los Angeles.
Costas Synolakis是洛杉矶市南加利福尼亚大学土木与环境工程系的海啸研究专家。
COSTAS SYNOLAKIS: "Japan is one of those most well-prepared countries on earth in terms of tsunami warning. They had a warning. I think what went wrong is that they had not anticipated the size of this event."
COSTAS SYNOLAKIS：“日本是世界上在海啸预警方面准备最为充分的国家之一。他们发出了海啸预警。我认为失误之处是他们没有预料到这次海啸规模如此之大。”
He says there are two reasons for this. Japan has not had any event anywhere near as big as this one in the last one hundred fifty years. And scientists had not expected such a large earthquake happening off the coast of Japan.
他表示这有2个原因。首先，在过去150年里日本附近从未发生过如此严重的灾难。同时，科学家也没有预料到日本海岸线附近会发生如此强烈的地震。
The nine point zero magnitude earthquake was the fourth most powerful earthquake ever recorded worldwide. It was also the worst earthquake ever to hit Japan. The tsunami waves that followed were reported to have reached as high as thirteen meters in some areas.
这次9级地震是有史以来世界范围内的第四大地震。也是日本有史以来最为严重的一次地震。据报道，随之而来的海啸在部分地区高达13米。
Costas Synolakis says Japan's concrete sea walls were not built to handle such high waves.
Costas Synolakis表示，日本修建的防波堤并不足以应付如此高的海浪。
COSTAS SYNOLAKIS: "The concrete seawalls in many places in Japan are about 10 meters, that's about 33 feet. In Sendai, they were about three meters, that's about 10 feet. So that shows you that at least in that area they were not expecting such a sizeable wave because they would have built a higher seawall."
COSTAS SYNOLAKIS：“日本大部分地方的防波堤高10米，大约33英尺。仙台防波堤高3米，大约10英尺。这些都显示，至少在这些地区，他们没有料想到如此大的海浪，否则他们会修建更高的防波堤。”
A tsunami wave can travel as fast as eight hundred kilometers per hour. To get to higher ground people would often have to travel for many kilometers. This can take more time than a fast traveling tsunami will permit. This is especially true in cases like Japan, where the center of the earthquake struck so close to the coastline. The tsunami waves followed almost immediately.
海啸波移动速度高达800公里/小时。人们转移到地势较高处通常需要行程数公里，这远远超出了海啸允许的时间。这在日本一类地震震中如此靠近海岸线的地方尤其如此，海啸几乎是紧随而来。
Experts say early warning systems will continue to be limited by these facts until earthquakes and tsunamis can be predicted.
专家表示，早期预警系统将继续受这类原因的限制，直到地震和海啸可以准确预测为止。