It's very hot in Florida where I live, but I have 0 expectations that the company I work at could have any measurable impact on a global issue of this magnitude, and Amazon doesn't get much closer.
I disagree. If everybody held the opinion that their actions wouldn't amount to anything, nothing would ever change. Climate change is the single largest event that will occur in our lifetimes, and we all need to help pitch in to stop the raise in global temperatures.
Amazon definitely could. Silicon Valley, as a whole? Definitely absolutely could.