If the release of information could affect you, don't trade until after its released. You are free to pretend the market is closed whenever you like.

And it's not like this risk isn't there anyway. Earthquakes rarely coordinate their timing with market hours, to name one example.

>Earthquakes rarely coordinate their timing with market hours, to name one example.

When speaking of trading and earthquakes, it's hard not to mention Nick Leeson.

The beginning of the end occurred on 16 January 1995, when Leeson placed a short straddle in the Singapore and Tokyo stock exchanges, essentially betting that the Japanese stock market would not move significantly overnight. However, the Kobe earthquake hit early in the morning on 17 January, sending Asian markets, and Leeson's trading positions, into a tailspin. Leeson attempted to recoup his losses by making a series of increasingly risky new trades (using a Long-Long Future Arbitrage), this time betting that the Nikkei Stock Average would make a rapid recovery. However, the recovery failed to materialize.

Leeson left a note reading "I'm Sorry" and fled Singapore on 23 February. Losses eventually reached £827 million (US$1.4 billion), twice the bank's available trading capital. After a failed bailout attempt, Barings was declared insolvent on 26 February.

http://en.wikipedia.org/wiki/Nick_Leeson

Trading is always open on exchanges around the world. So traders would duke it out by proxy instruments on a different exchange.

Well, depending on who is responsible for deciding when the data is released, you may have answered your own question.