What will be the consequences of the melting of the Arctic Ocean?

1. Impact on organisms in the Arctic Ocean

The reduction of sea ice in the Arctic Ocean directly affects various organisms living on and under the sea ice. One of polar bears' main food sources is seals that breathe or rest on Arctic sea ice, and polar bears are far less mobile than seals underwater. Therefore, the reduction of sea ice has seriously affected the hunting success rate of polar bears, leading to a sharp decline in their populations in recent decades.

In addition, although the melting of sea ice has a smaller impact on the volume of seawater than the melting of land ice sheets, it directly affects the salinity of seawater in sea ice areas. This significant reduction in salinity will change the living conditions of some plankton, thereby disrupting the entire marine food chain.

2. Impact on global climate

The reduction of Arctic sea ice will in turn affect the global climate. Since liquid water has a greater heat capacity than ice, once the Arctic Ocean loses its sea ice cover in summer, it will absorb and store more heat, disrupting the existing climate state in many aspects such as ocean currents and atmospheric circulation.

The extremely low-temperature air mass over the Arctic is surrounded by a circle of high-speed polar circulation and will not spread easily. Some studies have found that the disappearance of sea ice will weaken this high-speed polar circulation, causing cold air masses in the Arctic to spread to lower latitudes. In recent years, extreme cold weather has continued to occur in North America and Europe in winter, which is actually the result of global warming.

3. Shortening shipping

Reducing sea ice in the Arctic Ocean also has advantages. For example, in terms of shipping, the Arctic Ocean route has become possible, which will greatly shorten the navigation distance from the Pacific coast to Western Europe and Northern Europe, and provide many new and faster waterways connecting the East and the West. Compared with shipping via the Suez Canal, Can save 40% of transportation time and fuel costs.

4. Invasive alien species

Sea ice has long been a huge obstacle preventing ships and species from crossing the Arctic Ocean. Today, shipping is the most common route for invasive species in the ocean, accounting for 69% of newly introduced species, followed by aquaculture at 41% (non-native species can have more than one introduction route).

The most common method is ship ballast water. Organisms can also hide in the scale on the ship's hull, while forest pests, mosquitoes, etc. can survive on cargo pallets and ship cargo during long-term voyages ( Such as tires) etc.

Cold weather in the Arctic Ocean and shortened voyages caused by melting sea ice help invasive species such as oysters, barnacles and crabs survive. Cold water slows down organisms' metabolic rates, allowing them to survive with less food.

Extended information

The decrease in sea ice in the Arctic Ocean is also related to factors such as the tilt of the earth. Because the Earth's axis of rotation was once more tilted than it is now, causing the poles to receive more heat radiation, it is likely that there was an ice-free summer in the Arctic 10,000 years ago. However, changes in geological factors are extremely slow, at least in units of tens of thousands of years, so the current dramatic changes in sea ice area cannot be explained from this perspective.

A recent study published by American scientists in the academic journal "Climate" shows that the Arctic Ocean is likely to usher in its first "ice-free summer" in 2034.

Human carbon emissions are the most important factor affecting climate change over the past 200 years. If humans do not make substantial changes in reducing carbon emissions, the global average temperature will rise by more than 1.5 degrees Celsius by the end of this century. Without leap-forward technological development, this temperature increase will have irreversible effects. An ice-free summer in the Arctic Ocean may be just the beginning.

China Meteorological Administration-"Ice-free Summer" in the Arctic Ocean

People's Daily Online-Accelerating melting of the Arctic Ocean will bring threats of species invasion