Special recommendations on CAP for earthquakes
Many of our publishers specify the
<area> as a
<circle> centered at
the earthquake's epicenter. We strongly suggest that you specify a non-zero
radius instead of a single point, because Google Public Alerts are shown more
to users located inside the
<area> than to users outside of the
<area>. For example, your system can select a radius from a set of
predetermined radii values depending on the earthquake's magnitude or depth. If
you must set a zero-radius circle, please note that Google will have to choose a
non-zero targeting radius to use instead. Zero-radius circles are considered
empty target areas, which Google Public Alerts doesn't support.
Since many earthquakes are centered in remote or offshore locations, we also
suggest that you specify the value of the
<areaDesc> element in terms of
the epicenter's distance and direction from a more populated or better-known
area. For example:
<areaDesc>10 km SW of Christchurch</areaDesc>
This makes it easier for users to identify the location of the quake using one or more better-known reference points.
Please include separate parameters in your CAP for information that you use to help the public understand an earthquake's strength and intensity. This might include the earthquake's magnitude, intensity, depth, or origin time. For example:
<parameter> <valueName>Magnitude</valueName> <value>6.1</value> </parameter> <parameter> <valueName>Depth</valueName> <value>12 km</value> </parameter>
Google can then parse some of these structured parameters to construct alert
titles or other strings to display on Google Public Alerts. However, it's still a good
idea to include the same information in human-readable language in your CAP
<description>, as well.
Rich media resources
If you have an intensity shakemap image, epicenter map image, or other rich
media resources that you'd like to display with your alert, please use the
<resource> element to specify the type and content of the resource file.
The following semicolon-separated syntax expresses earthquake shake intensities and locations: