I find it useful to remove the value-laden words like 'good' and 'bad' from the discussion, and instead to be more direct if we are going to use adjectives about them. Tsunamis, earthquakes, hurricanes have occurred since long before there were people. They just happen.
It isn't the decision of a god that thousands will die when those happen. It may be the result of poor decisions over many years by people, or it may just be plain bad luck. It doesn't do us much good to try and read meaning into these events. It's more useful to try to deal with the aftermath.
The event is amazing (an island moved 100' in seconds last year), though completely explainable. The results to humans are scary, sad, ennobling, profound, and many other things. The results to the environment are dramatic, cataclysmic, etc. Not good, not bad, except perhaps with regard to a specific species or outcome.
Sometimes when tragedies occur to innocent ('good') people due to the actions of sociopaths, we have more trouble explaining or accepting it. It contravenes our values, it scares us because it could happen to us, it makes us question what people are capable of. But IMO the fact that some people are sociopaths is balanced by the fact that others--many others--are altruists. Being non-Christian, I don't think that people are innately good or bad, don't believe that people have fallen from grace or are filled with sin. I think human nature is complex and doesn't lend itself to easy characterization. In fact, it alarms me when people find it easy to make such characterizations and describe people or cultures as 'evil'.