[zamadatix]

Remember this is relative to temperature at the start of the graph (2000) not 2020.

But yes, there is a delay between "stop producing emissions" and "temperature starts going down". CO2 is already high, simply stopping additional output doesn't make the current amount go away overnight and there is still plenty of ice to melt over the seasons in the meantime.

[DennisP]

Specifically there's a delay of 10 to 30 years between releasing CO2 and getting the full temperature increase from it, just like there's a delay between turning on a stove burner and boiling water in a pot.

On top of that simple heating time, there are feedback effects like melting permafrost releasing additional greenhouse gases, and (as you mentioned) melting ice reducing the planetary albedo.