By drinking 32 oz of water how many calories have you burned?

Lots of sites say different things, some say you can burn 70 calories by drinking iced water, others say 100, but some also say only 2-3 calories can be burned. To be honest, I'm not sure but my best guess would be with 2-3 calories, because if it really burned up to 100 calories do you not think everybody would be trying to lose weight through drinking iced water by now?