Polar amplification happens when changes to the earth’s atmosphere lead to a larger difference in temperature near the north and south poles than to the rest of the world. This phenomenon is measured against the average temperature change of the planet. It can occur when the atmosphere’s net radiation balance is affected by an increase in greenhouse gases.
Greenhouse gases are naturally present in our atmosphere. However, if they are too concentrated, they prevent heat from escaping into space and cause the earth to warm. A recent post notes that climate change due to increased greenhouse gases is causing Arctic ice to melt.
Scientists generally agree that polar amplification is primarily caused by melting ice. Ice is more reflective and less absorbent of light than land or the surface of an ocean. When ice melts, it typically uncovers darker land or sea, leading to increased sunlight absorption.
Greater absorption of this solar radiation causes more heating and leads to increased melting. Scientists refer to this phenomenon as the ice-albedo feedback, where warming causes yet more warming to occur.
The Arctic versus Antarctic amplification
Antarctic amplification affects the South Pole, while Arctic amplification is felt in the North Pole. The earth’s poles are more sensitive to changes in climate and are warming faster than the rest of the planet.
According to NASA, the rate of ice loss in Antarctica has tripled since 2012 compared to ice losses from the previous two decades. The Antarctica Peninsula is experiencing one of the most rapid temperature changes on earth.
However, climate change has impacted the Arctic more than any other place in the world. During the past 30 years, the Arctic has warmed at roughly twice the rate as the entire planet, resulting in extreme polar amplification.
How is polar amplification related to climate change?
According to most scientists, the rapid warming of the poles is due to human-caused climate change. Some of the effects climate change has had on both the North and South poles in recent history are outlined below.
Melting ice
In the past 30 years, areas of Arctic sea ice have melted that is larger than Denmark, Norway, and Sweden combined. Since the Arctic helps regulate the world’s temperature, as more ice melts there, the warmer our planet becomes. The warmer our planet becomes, the more ice melts. It’s a brutal cycle.
Rising sea levels and temperatures
As polar ice caps melt, sea levels and temperatures everywhere are rising. According to Greenpeace, the global average sea level has increased between 4 to 8 inches in the past 100 years. Warmer temperatures can cause seawater to expand and more ice to melt, both of which can cause a rise in sea level.
Melting permafrost
Permafrost is ground that is frozen solid. It can be found throughout the Arctic as land and below some shallow parts of the Arctic Ocean. As temperatures rise, permafrost melts. This process releases carbon dioxide and trapped methane into the atmosphere. Since both are potent greenhouse gases, their release exacerbates global warming. This results in more permafrost melting.
Ice loss and melting permafrost lead to further global warming. Polar amplification has grave consequences for the entire planet. Because the Arctic helps cool the earth, changes in the Arctic climate could affect the rest of the world.
These arctic changes also influence the world’s food chain. The effects of polar amplification can be felt worldwide. From phytoplankton to marine mammals like polar bears, seals, whales, and walrus, nothing is immune to climate change.