Before
After
I had been living in Beijing for a long time and the biggest natural disaster we had there was sandstorm. It was very annoying but nobody would get killed. After I came to Singapore, another disaster free place, the biggest worry would be tsunami as Singapore is a small island country. Luckily we never had any and hopefully there won't be any in future.
We've seen many reports on the earthquakes and tsunami, the damage and casualties. But tornado is really far from my knowledge and most of time we could only see it from American movies. I might not have a chance to get to know its huge power until I read this report.
Quote from Wiki:
A tornado is a violent, dangerous, rotating column of air that is in contact of both the surface of earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. They are often referred to as a twister or cyclone. Tornadoes have been observed in every continents except Antarctica. However, the vast majority of tornadoes in the world occur in the Tornado Alley region of the US.
A tornado moves through Tuscaloosa, Alabama
A typical tornado has winds of 110 mph (175 km/h) or less, is approximately 250 feet (75 m) across, and travels a mile (1.6 km) or so before dissipating. However, tornadic behavior is extremely variable. Even the smallest tornado can kill.
Just two weeks ago at least 47 people died as storms tore a wide path from Oklahoma to North Carolina. Meanwhile the worst drought in more than 40 years intensified across Texas, with high winds and heat causing massive crop losses. Then on 28 April, this deadliest twister outbreak in nearly 40 years, killed at least 259 people in seven states. Even the US. president Barack Obama had announced he would visit Alabama where dozens of tornadoes struck.
So, here is my question, are we able to detect the tornadoes early enough to alert the residents to reduce damage and avoid deaths? What can we do?
In fact, study in warning of tornadoes began in US. in the mid-20th century. Before the 1950s, the only method to detect a tornado was by someone seeing it on the ground. Often, news of a tornado would reach a weather office after the storm. But, with the advent of weather radar, areas near a local office could get advance warning of several weather. The first public tornado warnings were issued in 1950 and the first tornado watches and convective outlooks in 1952. In 1953 it was confirmed that hook echoes are associated with tornadoes. By recognizing these radar signatures, meteorologists could detect thunderstorms likely producing tornadoes from dozens of miles away.
After the implementation of the WSR-88D network in the U.S., the probability of detection of tornadoes increased substantially. The average lead time rose from 4 minutes to 13 minutes, and a 2005 NOAA report estimated that as a result of improved warnings that there are 45% fewer fatalities and 40% fewer injuries annually. Other than the U.S. and Canada, very few other nations have specific tornado watch and warning services.
Although technology has improved and we are now equipped with powerful radar and even satellites to help forecast tornadoes, it is still not possible to detect and issue advance warnings all the time. Lessons are learnt and the experience gained through painful disasters.
I hope to see more and more advanced methods are innovated to detect tornadoes, and such tragedies would never happen again. And I am pleased to be living in such a peaceful and safe country as Singapore. I'd also like to thank my Geography teacher as he refers me to read the news about tornado and many other geographic facts which are very interesting and helpful.
In fact, study in warning of tornadoes began in US. in the mid-20th century. Before the 1950s, the only method to detect a tornado was by someone seeing it on the ground. Often, news of a tornado would reach a weather office after the storm. But, with the advent of weather radar, areas near a local office could get advance warning of several weather. The first public tornado warnings were issued in 1950 and the first tornado watches and convective outlooks in 1952. In 1953 it was confirmed that hook echoes are associated with tornadoes. By recognizing these radar signatures, meteorologists could detect thunderstorms likely producing tornadoes from dozens of miles away.
After the implementation of the WSR-88D network in the U.S., the probability of detection of tornadoes increased substantially. The average lead time rose from 4 minutes to 13 minutes, and a 2005 NOAA report estimated that as a result of improved warnings that there are 45% fewer fatalities and 40% fewer injuries annually. Other than the U.S. and Canada, very few other nations have specific tornado watch and warning services.
Although technology has improved and we are now equipped with powerful radar and even satellites to help forecast tornadoes, it is still not possible to detect and issue advance warnings all the time. Lessons are learnt and the experience gained through painful disasters.
I hope to see more and more advanced methods are innovated to detect tornadoes, and such tragedies would never happen again. And I am pleased to be living in such a peaceful and safe country as Singapore. I'd also like to thank my Geography teacher as he refers me to read the news about tornado and many other geographic facts which are very interesting and helpful.
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