Arctic’s 40-year record low temperatures spawn rare clouds
Image credit: Branca Cristina via SpaceWeather. Captured on December 22, 2023, at Locarno, Switzerland
NASA’s MERRA-2 climate model reveals that the Arctic stratosphere has reached a 40-year record low for December, creating a sudden appearance of polar stratospheric clouds (PSCs) far beyond their usual Arctic confines.
Recent observations have revealed a remarkable surge in polar stratospheric clouds (PSCs), often referred to as the most beautiful clouds on Earth due to their aurora-like colors.
This sudden increase is attributed to a 40-year record low in temperatures within the Arctic stratosphere for the month of December, as indicated by NASA’s MERRA-2 climate model.
PSCs form under extremely cold conditions, typically around -85 °C (-121 °F), in the otherwise cloudless stratosphere. The unusual cold snap has caused these clouds, usually confined to the Arctic, to descend all the way to mid-latitudes.
Notable sightings have been reported over Locarno, Switzerland, Torun, Italy, and Lausanne, Switzerland, locations well beyond the normal range of PSCs.
This phenomenon represents a significant deviation from the typical January start of the PSC season. The current extreme cold wave has not only given rise to an early onset of these clouds but also suggests the potential for increased occurrences in the coming weeks.
On December 24, 2023, the Arctic stratosphere is warming but it’s still cold enough for polar stratospheric clouds.
References:
1 Record-cold weather in the stratosphere – SpaceWeather – December 23, 2023
The Watchers team and our contributors bring the latest on extreme weather, earthquakes, volcanic eruptions, space weather, and all things science. We're all about making sense of the natural world and keeping you informed on what’s happening. Got a tip or a question? Hit us up using the form at newstips!
Published in the last 24 hours
- In 1943, a flight instructor in Texas flew a two-seat training plane into the eye of a hurricane because he was curious, then landed and took the base weatherman up for a second pass Epicenter
- A soy sauce maker used fire to guide villagers through Japan’s 1854 tsunami, then funded a seawall that protected most of Hiro in 1946 Epicenter
- In 2013 a landslide fell onto Svínafellsjökull in southeast Iceland, leaving thicker ice at the foot of the slope; that ice is now moving away and the mountainside has shifted 1 to 3 cm. Epicenter
- Kīlauea's north vent threw lava about 660 feet (200 m) high for six hours on 5 November 2026; the summit is now reinflating, with the next episode forecast for 16 to 21 November. Epicenter
