Jesus warned us that such things would happen. More to the point, John the Revelator warned that war, economic depression (translated as "famine"), and pestilence (the pale horse; Greek chloros a sickly pale green, whence "chlorine") would kill off twenty-five percent of the people then living when the second, third, and fourth Seals break [Revelation 6:3-8]. Nor is this all, of course: recall the Sixth Trumpet, that will in its time kill one-third of the people remaining alive at that time.
And consider this: some commentators have already compared the death toll to the Flood of Noah [Genesis 6-8]. That's an exaggeration, of course, because that Flood killed all but eight people. In fact, the late tsunami is a taste--just a taste--of what is to come.