Arnie Coro, CO2KK, International Amateur Radio Union (IARU) Region II Area C Emergency Coordinator, advises users of the 40 and 20 meters bands to "be aware of possible (earthquake) emergency communications traffic taking place in and around the affected areas of New Zealand's South Island, where Christchurch is located."
According to Warren Harris, ZL2AJ, of Hastings, NZ, designated EmComm frequencies used by AREC NZ on HF for the Christchurch Earthquake are:
3.900 MHz USB 5.320 MHz USB 7.100 MHz USB
CO2KK continues: "This is a city of about 400,000 population and it was hit pretty badly because of the proximity of the epicenter of the earthquake and the fact that it was registered at a very shallow depth and very near to the city.
"The propagation on 40 meters more likely to cause problems to the New Zealanders from unintentional QRM coming from the Americas is the window that starts about two orthree hours before sunrise and lasts until sunrise at this end. A similar pattern, with a slight time shift shows up on 20 meters, too."
(You Tube video courtesy of Sky News)