Scientists discover 'atmospheric rivers' in the skies over Antarctica

Imagine an invisible river stretching hundreds of kilometers and flowing through the atmosphere from the tropics to the polar regions. This river does not appear on maps, has no channel or banks, yet it carries enough water vapor to alter the mass balance of the Antarctic ice sheet and influence sea levels. This is the finding of a study recently published in the scientific journal Geophysical Research Letters, conducted by a team of Japanese researchers who developed an unprecedented tool for visualizing these atmospheric rivers. According to Al Jazeera, atmospheric rivers are narrow, elongated corridors of water vapor that sweep through the atmosphere from the tropics to the poles, and have been known to scientists for decades. However, their true extent remained shrouded in mystery due to the difficulty of observing them over Antarctica, owing to the continent’s rugged terrain and dry air, which hinder traditional observation methods. Kazu Takahashi, a PhD student at the Japanese Institute for Advanced Study (SOKENDAI) and lead author of the study, summarized these phenomena by stating, “They transport moisture from the tropics and mid-latitude regions to the poles.” He added in an interview with Al Jazeera Net, “When this moisture reaches Antarctica, it can condense to form clouds and then snow, making it one of the primary sources of snowfall on the continent.” Another striking aspect of this phenomenon is its scale and significant impact. The latest study revealed that atmospheric rivers are responsible for 30% to 60% of total annual precipitation in the interior regions of Antarctica, with this proportion rising to 90% in some coastal areas along the western part of the continent. Takahashi explained that “most of the Antarctic Plateau is an extremely arid environment, where only small amounts of snow fall on ordinary days. Atmospheric rivers can bring snowfall amounts that exceed normal levels by many times in a single event.”