Rising carbon dioxide levels lead to long-term warming, but full effects take thousands of years due to slow natural processes. New research shows high-latitude regions may warm more than short-term climate models currently predict. Let’s know more.
It’s well known that increasing levels of carbon dioxide in the atmosphere lead to a rise in Earth’s atmosphere. However, the complete effects of this warming do not always occur immediately. Due to slow natural processes such as the ocean absorbing heat and changes in the carbon cycle, it can take decades or even thousands of years for the planet to reach a new stable temperature.
Climate models are used to predict how quickly and to what extent Earth will warm. Yet, these models sometimes differ in their predictions about when the planet will settle into this new temperature. One reason for this uncertainty is known as the “pattern effect.” This refers to how the uneven warming of the ocean’s surface influences weather patterns. These factors can either accelerate or slow down the overall warming process, making climate predictions complex.
Using Earth’s History as a Guide
To better understand how the climate might change over long periods, scientists examine past climates; this is called paleoclimate data. By studying times when the Earth was warmer than today, they can identify patterns that help predict future conditions.
A research team led by Yi Ge Zhang studied sea surface temperature records from the past 10 million years. The aim was to observe how different areas of the ocean warmed as carbon dioxide levels increased over very long timescales. Their findings were published in the journal AGU Advanced.
The Western Pacific Warm Pool as a Reference
The researchers focused on the Western Pacific Warm Pool, which is the largest and warmest area of surface water on the planet. They used its temperature as a reference point and compared it with temperatures from 17 other ocean regions to identify a global warming pattern. They them compared these ancient warming patterns with results from climate models. These models simulated the possible effects of carbon dioxide levels rising to four times their preindustrial levels.
Similar Patterns Over Thousands of Years
Both the ancient data and the models sowed similar long-term warming trends, especially in high-latitude regions such as the poles. This means that areas like the North Pacific, North Atlantic, and Southern Ocean warmed more over thousands of years.
However, when comparing these patterns to temperature trends from the past 160 years, the results were different. This is because current warming is still influenced by processes such as the ocean absorbing heat. The ancient data reflects the full effect of warming after thousands of years, when the climate has reached a new balance.
What This Means for the Future
The study suggests that it will take thousands of years for Earth to reach a new temperature balance after the current increase in CO₂. In the future, warming is expected to be more pronounced in middle and high-latitude regions than what short-term climate projections indicate. This means that areas like the North Pacific, North Atlantic, and Southern Ocean may experience more warming than previously thought, especially over long timescales. High-latitude warming is likely to be more noticeable over thousands of years rather than just over a century.
Understanding these long-term patterns helps scientists make better predictions about how Earth’s climate might change in the distant future.