Correção de sentenças "I thought about the global warming.."

Is it correct to say "I thought about the global warming when I've been to Brazil"? Or should I say "I had thought about the global warming when I've been to Brazil"? Or both are incorrect? :S

What's the translation of this for you? I'd like to know if I'm passing my thoughts correctly! :)

PS: If I've written something wrongly above, please, just let me know! :D

Thanx in advance, guys! :D
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Avatar do usuário Carls 3140 2 74
I think the first one the best option:

"I thought about the global warming when I've been to Brazil"
Avatar do usuário Rodzilla 30
I'd change "when I've been to Brazil" to "when I was in Brazil". Not sure it's wrong, but the second one just seems more natural to me.
Avatar do usuário Donay Mendonça 49075 21 73 1138
Complemento:

"I thought about global warming when I came to Brazil.''
"I thought about global warming when I went to Brazil.''
So many options! :D
But I could understand all of them!

Thanx a lot, guys! ;)