If you have a spinning top, and apply friction, the top slows.
Since we have put up these huge windmills, that might cause friction that could slow the Earths rotation.
I have invented a new crisis: GLOBAL SLOWING!
China beat you to it....wezz all dooommmed!
“Three Gorges Dam crosses the Yangtze River in Hubei province, China. It is the world’s largest hydroelectric power station by total capacity, which will be 22,500 MW when completed. When the water level is at maximum....it will flood a total area of 632 km2 of land. The reservoir will contain about 39.3 cubic km (9.43 cubic miles) of water. That water will weigh more than 39 trillion kilograms (42 billion tons).
A shift in a mass of that size will impact the rotation of the Earth due to a phenomena known as “the moment of inertia”, which is the inertia of a rigid rotating body with respect to its rotation. The moment of inertia of an object about a given axis describes how difficult it is to change its angular motion about that axis. The longer the distance of a mass to its axis of rotation, the slower it will spin. You may not know it, but you see examples of this in everyday life. For example, a figure skater attempting to spin faster will draw her arms tight to her body, and thereby reduce her moment of inertia. Similarly, a diver attempting to somersault faster will bring his body into a tucked position.
Raising 39 trillion kilograms of water 175 meters above sea level will increase the Earth’s moment of inertia, and thus slow its rotation. However, the impact will be extremely small. NASA scientists calculated the shift of such a mass will increase the length of day by only 0.06 microseconds, and make the Earth only very slightly more round in the middle and more flat on the top. It will also shift the pole position by about two centimeters (0.8 inch). Note that a shift in any object’s mass on the Earth relative to its axis of rotation will change its moment of inertia, although most shifts are too small to be measured (but they can be calculated).”
https://futurism.com/how-infamous-hydroelectric-dam-changed-earths-rotation
We better sound the alarm next spring when days start getting longer.