The State of Early Warning Systems - Reducing Disaster: Early Warning Systems for Climate Change - page 110

is being tested. The Tsunami Early Warning System for the North-eastern Atlantic,
the Mediterranean, and connected seas is also undergoing testing.
The Pacifi c basin is monitored by the Pacifi c Tsunami Warning System (PTWS),
created by 26 member states. Its activities are carried out by the Pacifi c Tsunami
Warning Center (PTWC) in Hawaii and are operated by the National Weather
Service (NWS) of the National Oceanic and Atmospheric Administration (NOAA).
NWS also maintains the Alaska Tsunami Warning Center (ATWC) that covers
Alaska, British Columbia, Washington, Oregon, and California. PTWS monitors
seismic stations of PTWC, but also of USGS and ATWC, to detect potentially tsu-
namigenic earthquakes.

6.3.3.4 Volcanic Eruptions

EWSs for volcanic eruptions are based on monitoring of precursors (i.e., seismic
activity, ground deformation, gas releases), visual observations, and surveying to
detect volcanic activity.
Volcano observatories are distributed worldwide and are available at the World
Organization of Volcanic Observatories (WOVO) website. Japan, the United States,
and most Central and South American countries (Mexico, Guatemala, El Salvador,
Nicaragua, Costa Rica, Colombia, Ecuador, Peru, Chile, Trinidad, and the Antilles)
have volcano observatories. By contrast, in Africa, only two countries (Congo and
Cameroon) have volcano monitoring observatories and the information is not pub-
licly accessible. Due to inadequate resources, a small number, fewer than 50, of the
world's volcanoes are being monitored (National Hazards Working Group 2005 ).
On a global scale, the Smithsonian institution, together with the USGS under the
Global Volcanism Program, provides online access to volcanic activity information,
on a daily and weekly basis (see Fig. 6.2 ). The information is also available through
Google Earth.
In addition, several volcanic ash advisory centers exist worldwide which provide
information to the aviation sector (London, Toulouse, Anchorage, Washington,
Montreal, Darwin, Wellington, Tokyo, and Buenos Aires).

6.3.4 Wildfi res

EWSs for wildfi res provide early warning information based on the prediction of
precursors, such as fuel loads and lightning danger. Once the fi re has begun, fi re
propagation patterns are estimated based on fi re behavior and pattern modeling.
Further details about early warning for wildfi res are provided in another chapter of
this topic.
Currently many countries have fi re-monitoring systems, such as Canada, South
America, Mexico, and South Africa. In Brazil, INPE, the Brazilian Space Research