Which of the following statements correctly identifies a natural factor affecting global climate change and its corresponding physical mechanism?
Milankovitch cycles — An increase in the Earth's axial tilt (obliquity) minimizes seasonal temperature variations, allowing winter snow to persist through the summer and trigger glaciation.
Solar output — The 11-year sunspot cycle drives permanent, long-term shifts in the Earth's climate by directly altering the composition of greenhouse gases in the troposphere.
Volcanic activity — Large explosive eruptions inject sulfur dioxide (SO2SO_2SO2) into the stratosphere, forming highly reflective aerosol plumes that increase planetary albedo and cause temporary global cooling.
Ocean currents — A sudden shutdown of the thermohaline circulation causes rapid, uniform global warming due to the accumulation of heat in deep ocean basins.
