Compare:
Heat has an effect on wax. It makes the wax soft.
{Everything you do} {has an effect on} the climate.
X has an effect on Y = X affects Y
The phrase "carbon footprint" is a coinage that refers to the cumulative effect everything you do has on the climate.
Alternatively:
The phrase "carbon footprint" is a coinage that refers to the cumulative effect on the climate of everything you do.
The phrase "carbon footprint" is a coinage that refers to the cumulative effect of everything you do on the climate.
The book is about the effect of acid rain on crops.
The books is about acid rain's effect on crops.
The book is about the effect acid rain has on crops.
The book is about how acid rain affects crops.
The book is about the effect on crops that acid rain has.