This is reported here fairly often (has happened on both
of my Volvos).

The coolant overflow tank has a sensor that detects low coolant.
You are just a bit low and when you accelerate the fluid is pushed
to the back of the bottle momentarily triggering the sensor/light.

You need to top off the coolant.

Note: Don't open the coolant cap unless the engine is cold.

Older gray colored coolant overflow tank caps are known to leak a bit.
Newer blue / green /teal (depend on who you ask) are improved. You
might want to replace the cap with a newer one in case the current
one is leaking a bit when under pressure.