Rough Sketches of symbol designs

I just did some rough sketches of the global warming awareness symbols, but I'm not sure to choose which one to be the one for assignment yet because there's none of the symbols i really satisfy yet.
I planning to focus the natural disasters as the effect of global warming to be small area of global warming, I wondering whether is "natural disaster" is too broad? or I should choose one of the natural disasters to be more specific of the concept of my symbol.
I still very blur or confused about choosing which effects to be my main concept of my symbol.. @_@"

I like the devil symbol

I think this eyed shape symbol's idea is too broad as I put hurricane and tsunami as the examples of the natural disaster caused by global warming together in one symbol, izzit ok? or i should be more specific?

Images I found while I using Google to search for images...