Another hypothesis, published in 2021, states that the length and intensity of winters in the Southern Hemisphere can determine the time of the end of the Ice Age. This hypothesis is apparently against Milankovitch’s theory, which says that summers in the Northern Hemisphere cause climate change.
Long winters in the Southern Hemisphere change wind patterns near the tropics and can produce frequent storms in an area of the Pacific known as the “tropical warm pool” (a region of ocean that stores and releases large amounts of heat). Shifting winds can create storms in this area. Hurricanes put a lot of water vapor into the air, and water vapor can act as a greenhouse gas.
Another idea is that the salty water of the Indian Ocean spilled into the Atlantic Ocean, contributing to the end of the last ice age. The decrease in sea level had caused the interruption of the flow that went from the Pacific Ocean to the Indian Ocean, and thus the water in the Indian Ocean had become very salty. Normally, the current would dilute the very salty tropical waters of the Indian Ocean.
Changes in wind patterns and currents in the Indian Ocean could have caused the Indian Ocean to dump large amounts of salt water into the Atlantic Ocean, changing its temperature and currents in both the Northern and Southern Hemispheres.
More evidence is needed to confirm whether either hypothesis can explain why the last ice age ended, but scientists continue to investigate.