Several websites are dedicated to monitoring Earth's seismicity over time. They make an interesting comparison in terms of graphical representation, considering that they are all reporting on the same information. Check them out and decide which one you think does the best job.

Earthquake Watch is a homemade site using Google Maps to show quake locations and magnitude. It shows magnitude, but only quakes in the last day, without differentiating between quakes in the past hour and longer times. Because it's done using Google Maps, it can be centered wherever you want -- or wherever the earthquakes happen. This is in contrast to the next two options, which have a fixed map centered on the Pacific Basin.

The USGS uses a nice physiographic map as the base for their information display. A series of colored squares of different sizes show magnitude and time of the quake. This is an advantage over the first site: more information revealed in the same amount of space. Still, like the first site, the map is small -- roughly 40% of the total "real estate" available on the screen.

The IRIS Seismic Monitor is my favorite of the bunch. It has a large map (~70% of the screen) with blinking circles of different sizes and colors show information about when a quake happened: last hour, last day, last two weeks, and the past five years. It also offers an option for a huge map (larger than the whole screen). Additionally, it offers a global night shadow -- so you can see which portion of the planet is in daylight, and which half is sleeping through the night.

Labels: earthquakes, graphics