What happened in the 17th and 18th centuries when solar output decreased just a little bit (indicated by almost no sunspots)?

Little Ice Age Period...

Explanation:

In 17th and 18th century, there was a little period of ice age in Europe and North America. However, there was no sun spots noted in  the sun that are called as solar minima yet there was a little ice age period that some refer to arise of global cooling.

Astronomers and other scientists are also working on the study of sun like stars and Earth like planets that'll eventually helps us to predict the next ice age if it is ever going to be happened.

diagram is missing, but i will try to explain your doubt.

answer:

amplitude is the maximum displacement or distance moved on a point of a vibrating body or wave measured from its equilibrium position.it is equal to half the length of vibration path.

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

hope this : d