Researchers at the University of California, Riverside have scientifically explained how global warming can cause an ice age. This was reported by Zamin.uz.
They identified an important factor in the Earth's carbon cycle that had not received enough attention before. This factor helps explain why ancient ice ages were sharp and severe.
The research results were published in the journal “Science.” According to previous views of scientists, the climate stabilizes through the weathering of mountain rocks.
Rain absorbs carbon dioxide from the atmosphere, falls to the land, and weathers silicate rocks through water. In this process, carbon is transported to the oceans.
In the ocean, carbon combines with calcium to form shells and limestone layers, which are preserved for millions of years. This process gradually reduces the amount of carbon dioxide in the atmosphere.
According to geologist Andy Ridgwell, as the planet warms, this process accelerates, absorbing more carbon and causing the Earth to begin cooling. Previously, this system was thought to stabilize the climate smoothly.
However, geological evidence shows that some ice ages covered almost the entire planet with ice and snow. This situation is difficult to explain with a simple stability mechanism.
Researchers discovered an additional process that enhances carbon burial in the ocean at high temperatures. When the temperature rises, precipitation brings many nutrients like phosphorus to the ocean.
This leads to an increase in plankton that absorb carbon dioxide through photosynthesis. When plankton die, they sink to the ocean floor, storing large amounts of carbon.
However, this process becomes complex. Excessive plankton growth reduces oxygen levels in the ocean.
Due to oxygen deficiency, phosphorus is released back into the water, stimulating the growth of new plankton. This process becomes cyclical, leading to massive carbon burial and a sharp drop in global temperature.
Ridgwell compares this process to an air conditioning system: it usually stabilizes temperature but can cause severe cooling in some cases. Computer models have also confirmed that this mechanism is strong enough to trigger the onset of an ice age.
Scientists believe that in ancient times, the climate system operated stably because atmospheric oxygen levels were low. Today, oxygen levels are much higher, so future cooling processes may not be as severe as in those times.
Nevertheless, this mechanism could accelerate the onset of the next ice age. Experts also emphasize that this fact should not reassure people.
The next ice age may occur in hundreds of thousands of years, but today's global warming remains the greatest threat for the current generation.
