I can’t say this with any authority, but I think the biggest effect would be in weather patterns and the subsequent downstream effects of having different weather.
Nah, the biggest effect would be in every single thing at or above ground level being instantly shot eastward at somewhere between 0 and 1,000 miles per hour. After that the weather is pretty much irrelevant because anything that would experience it would be dead as shit.
I mean, sure, there will be some people on the lower end of that 0-1,000 MPH curve that are not in very close vicinity to any objects to splort against. Inupiat, Aleut, Sami, Yamalo-Nenets... anyone inside the arctic circle should be relatively fine, speed-wise.