Final answer:
Changes in solar irradiation do not explain current climate changes primarily due to human-induced greenhouse gas emissions and the albedo effect from melting ice caps.
Step-by-step explanation:
Changes in solar irradiation do not explain current climate changes primarily because of human-induced greenhouse gas emissions and the albedo effect from melting ice caps. The sun's energy reaching Earth, as well as variations in solar intensity, have influenced Earth's climate in the past, but recent climate changes cannot be explained by changes in solar activity alone. Furthermore, human activities, particularly the combustion of fossil fuels, are responsible for most of the observed warming since the mid-20th century.