Final answer:
When glaciers begin to grow, there is a lag between changes in insolation and changes in ice volume due to various factors, including the time it takes for the Earth's surface to cool down, the accumulation of snowfall, and the slow response of glaciers to environmental changes.
Step-by-step explanation:
When glaciers begin to grow, there is a lag between changes in insolation and changes in ice volume because of several factors.
Firstly, changes in insolation may take time to affect the temperature of the Earth's surface, including glaciers. Insolation refers to the amount of solar radiation received by the Earth, and it can be influenced by various factors such as clouds, atmospheric conditions, and the angle at which sunlight reaches the Earth's surface. Therefore, even if there is a decrease in insolation, it may take time for the Earth's surface to cool down and for glaciers to start growing.
Secondly, the growth of glaciers depends not only on temperature but also on the accumulation of snowfall. Glaciers require a sustained period of snowfall to accumulate enough ice to grow. If there is a decrease in insolation, it may result in a decrease in snowfall as well, further delaying the growth of glaciers.
Lastly, glaciers are massive bodies of ice that take a long time to respond to changes in their environment. They move extremely slowly, and it can take years or even decades for changes in temperature and snowfall to translate into visible changes in ice volume.