Astronaut: Assuming you're not just trolling, simply go to redcross.org, savethechildren.org, islamic-relief.com, or any of the other major humanitarian orgs. They might have special drives for particular disasters, but I don't think you can earmark your funds to specifically help the victims of a particular disaster. In fact, I'd be suspicious of an organization that claimed to -- good chance it's a scam.
If I remember correctly (it's very possible I do not) red cross has the lowest margin of administrative fees; so more of your money goes to the victims.
But why not just adopt a young orphan sex slave with that money instead?