Wednesday, March 10, 2010
Is the number of earthquakes increasing? An Interesting Analysis, worth sharing.
According to the United States Geological Survey, no.
Technology has increased the amount of earthquakes that are detected and reported. Today, there are thousands of stations, compared to about 350 in 1931. The increase of stations has allowed scientists to detect earthquakes that would not have been decades ago.
Rapid improvements in global communications have enabled news of an earthquake to spread almost instantly. Several decades ago, the USGS said, it could take weeks after an earthquake to make the newspapers, often landing on the back pages.
Population booms are also contributing the the perception that there are more earthquakes. Many of these population increases are in earthquake-prone areas, so there is a higher possibility of more casualties when a major quake strikes.
"We have not seen any statistical increase in the number of earthquakes if you look back over the tens and hundreds of years," said Paul Earle, a USGS seismologist. "However, unfortunately the recent earthquakes have impacted populated areas, which brings them into the news, and people become more aware of the earthquakes."
In 1960, Haiti had a population of 3.87 million, according to the World Bank data finder. Since then, it has more than doubled to 9.84 million as of 2008.
Based on records kept since 1900, the USGS expects a yearly total of 17 major earthquakes and one great earthquake. Major earthquakes are those between 7.0 and 7.9 on the Richter scale, while great earthquakes are classified as 8.0 and above.
Since 1990, the amount of major earthquakes has stayed relatively constant. This estimation of 17 quakes has not been exceeded, with the highest number of 16 major quakes occurring in 2009. (Taken from AccuWeather.com's Gina Cherundolo)
There are around 500 number of Rain Gauge stations available in Tamil Nadu which are maintained by WRO, TNEB and mostly by Revenue Departm...