We can use essential oils for just about anything.
Plants are here to help us deal with the environment, and essential oils (I like to think of them as the 'liquid intelligence of nature') can help us cool down when we are hot!
An excellent oil for cooling is peppermint.
Just diffusing peppermint in the summertime can uplift and cool the environment.
Another great way to use peppermint is to put a drop of a therapeutic grade peppermint oil in your glass of water.