A year ago I published an article in Plus magazine debunking claims buzzing around the internet about a supposed recent increase in earthquakes and volcanic eruptions and so on. In that article I showed in detail how anyone can analyze publicly available data to put such claims to the test. In the current post, I present a brief update on earthquake statistics, showing that there still is no need to worry.
In the earlier Plus article, I showed how earthquake data can be downloaded from the USGS and analyzed for any trends. I chose to look at earthquakes of magnitude 5 and larger (M5+), as those are the ones that can potentially cause damage or even casualties. I showed two graphs, one with monthly earthquake counts from January 1996 to December 2016, and one with yearly counts for the same range of years. For details, also on the statistical analysis, see the original article.
This data showed that there was indeed a significant build-up in number of earthquakes from the early 2000s until 2011. However, after the major M9.0 earthquake off the coast of Japan in March of 2011, there was a clear drop in number of earthquakes, bringing it back to the level it was about 10 years earlier, and staying at that level until the end of 2016.
I have updated these statistics to include all of 2017, and this shows no change in the situation. In fact, the number of earthquakes in 2017 is roughly equal to what it was in 2000. The next plot shows the monthly counts from January 1996 until December 2017. The red line is a 12-month running average.
The next plot shows the yearly counts for 1996 until 2017. It clearly shows that after the major 2011 event, the level of earthquakes has remained at a roughly constant level, close to what it was back in 2000.
In conclusion, there is still no evidence at all that there has been a continuous increase in the number of earthquakes recently. There has been a significant increase during the first decade of the 21st century. However, since then things seem have gone back to “normal” levels again, and have stayed that way. Keep an eye out for the next update a year from now… 😉