Please could you help me finding global warming video with ice melting in glass time messurment scene?
This is probably not the specific video you are looking for, but here is one:

The video Latent heat of fusion shows the effect that you mean in a real world situation where the water is not mixed well.
The video Determination of Melting Point of Ice shows it under more controlled conditions.

The video Heat in changes of state explains it with a graph.

The video Energy required to melt ice and warm the water gives you an actual calculation example and shows the energy involved in melting ice vs. heating water.