What do we call unprecedented population explosion in the 1950's?

The population explosion first started in the late 18th century(started around 1750), and it was rather small scale, form 1750 until 1950's. From 1950 on, a much more substantial and intensive population explosion started to take place in Asia, Latin America and Africa. Asia, for example had 1.4 billion people in 1950's, while in 2010, the number grew to 4.2 billion.