What artists (dead or alive) painted nature in a very wild form?

Question

I'm looking for artists who painted nature in a very wild and dramatic form.

Answer 1

John Martin. 
http://en.wikipedia.org/wiki/John_Martin... 
http://commons.wikimedia.org/wiki/Catego... 
Francis Danby. 
http://en.wikipedia.org/wiki/Francis_Dan... 
http://commons.wikimedia.org/wiki/Catego... 
J.M.W. Turner. 
http://en.wikipedia.org/wiki/J._M._W._Tu... 
http://commons.wikimedia.org/wiki/J._M._... 

Also some of the Hudson River school painters, eg. 
Albert Bierstadt 
http://en.wikipedia.org/wiki/Albert_Bier... 
Frederic Edwin Church 
http://en.wikipedia.org/wiki/Frederic_Ed... 

Hudson River school; 
http://en.wikipedia.org/wiki/Hudson_Rive...

Answer 2

Winslow Homer's Maine paintings fit the bill. See "Maine and Maturity" on the site below:

You might also look at Frederick Church, though his works and those of the Hudson River School sometimes "tame" and either aggrandize or prettify natural scenes. The Hudson River School painters were, after all, heavily influenced by Romanticism.