Regional Tsunami Service Providers The Pacific Tsunami Warning Center (PTWC), Honolulu, USA serves as the interim Regional Tsunami Service Provider for the ICG/CARIBE EWS. The Sub-regional center in Alaska (US National Tsunami Warning Center), USA works closely with the PTWC and currently provides warning services to Puerto Rico and the US and British Virgin Islands. The centers issue tsunami alerts to designated national authorities who then take action to protect their populations. The US Caribbean Tsunami Warning Program (CTWP) was established in Mayaguez, Puerto Rico in 2010. The CTWP monitors the tsunami monitoring, detection and warning capabilities and supports CTIC in the enhancement of tsunami readiness through outreach, education and training activities in the Caribbean and Adjacent regions in support of the ICG/CARIBE EWS.