Greenland, the world’s largest island, is defined by a climate of profound, relentless cold. The true severity of the Greenlandic climate is the result of a unique confluence of atmospheric, terrestrial, and oceanic factors. The extreme cold is not solely a consequence of its far northern location, but rather an amplification of that latitude by a massive, permanent ice sheet and surrounding frigid currents. To understand why this landmass is so cold requires examining how solar energy is received, how the landscape interacts with that energy, and how the surrounding water reinforces the Arctic conditions.
High Latitude and Low Solar Energy
Greenland’s position, spanning latitudes from approximately 60°N to over 83°N, means it receives a vastly reduced amount of solar energy compared to regions closer to the equator. This is due to the low angle at which the sun’s rays strike the Earth’s surface. When sunlight hits at a low angle, the same amount of solar energy is spread out over a much larger surface area, resulting in less concentrated heating per square meter.
The low angle also forces incoming sunlight to travel a longer path through the atmosphere. This extended journey increases the chances of the solar radiation being scattered or absorbed by atmospheric gases, clouds, and particles before reaching the ground surface.
During the winter, the effect of high latitude plunges much of the island into the complete darkness of the polar night. For months, the sun does not rise above the horizon, resulting in a net annual energy deficit where the land radiates more heat back into space than it receives. For a location like northern Greenland (around 82° N), the annual total solar insolation can be extremely low. The short summer period is unable to compensate for the long, dark winter, setting the baseline for Greenland’s freezing temperatures.
The Role of the Greenland Ice Sheet
The massive, ancient ice sheet covering approximately 80% of Greenland acts as the primary amplifier of the cold initiated by the island’s latitude. Its effect on temperature is dominated by its extremely high albedo, which measures how reflective a surface is. Fresh snow constantly refreshes the surface and reflects up to 84% of incoming solar radiation back into space. This high reflectivity prevents the sun’s limited energy from being absorbed and converted into heat, effectively cooling the surface. Even bare glacial ice, which is darker, still maintains a significant albedo, reflecting between 20% and 60% of solar energy.
Beyond its reflective surface, the sheer physical size of the ice sheet further contributes to the cold by creating high elevation. The ice forms a dome-like shape, reaching elevations of over 3,200 meters (nearly 10,500 feet) in the interior. According to the atmospheric lapse rate, temperature decreases with increasing altitude, typically by about 6.5 degrees Celsius for every 1,000 meters of elevation gain. This immense altitude means the central, highest parts of the ice sheet are consistently colder than the coastal regions at sea level. The permanent mass of ice and the overlying cold air dome function as a massive reservoir of frigid air that spills outward and downward, constantly reinforcing low temperatures across the entire island.
Influence of Ocean Currents
The ocean surrounding Greenland plays a significant, reinforcing role in maintaining the island’s low temperatures, primarily through the circulation of cold water. The most influential factor is the East Greenland Current, which flows southward along the entire eastern coast of the island. This current is a conveyor belt of frigid, low-salinity water originating from the Arctic Ocean. Crucially, the East Greenland Current exports the majority of the Arctic’s sea ice, carrying vast fields of ice floes southward toward the North Atlantic. The presence of this immense volume of ice and near-freezing water keeps the eastern coastal environment locked in an Arctic climate.
While a branch of the warm North Atlantic Current, known as the Irminger Current, flows near the southern and western coasts, its warming influence is largely mitigated. The East Greenland Current’s cold outflow often mixes with or dominates the western side, and the ice sheet shields the interior from any oceanic warmth. The cold currents and the export of ice thus perpetually chill the ocean-air boundary.