Ruapehu’s Crater Lake temperature slowly increases, New Zealand
Te Wai ā-moe, the Crater Lake of Ruapehu volcano in New Zealand, is experiencing a mild heating trend, with temperatures rising from 8 °C (46.4 °F) to approximately 10 – 11 °C (50 – 51.8 °F). The recent changes have been noted in late October 2024, following several months of cooling that began in February of the same year.
Mount Ruapehu satellite image on October 21, 2024. Credit: CopernicusEU/Sentinel-2, EO Browser, The Watchers
The lake temperature has progressively increased from a low of 8 °C (46 °F) in early October to approximately 10 – 11 °C (50 – 52 °F) by late October.
Despite the minor increase in lake temperature, volcanic tremor remains weak, and no significant seismic activity has been recorded.
The lake began cooling in February, dropping from approximately 30 °C (86 °F) to a low of 8 °C (46.4 °F) by early October. During this period, sulfur dioxide (SO2) emissions from the lake decreased, and volcanic tremors subsided, aligning with the cooling hydrothermal system beneath the lake.
With the reduction in upward heat flow, some mineral sealing was also expected beneath the lake, potentially reducing the rate of gas emissions through the lake. Although SO2 emissions declined between February and October 2024, they did not completely cease, indicating that the vent remained partially open during this cooling period.
This observation is consistent with weak upwellings and floating sulfur strands observed on the lake’s surface.
The scientists anticipate a gradual heating trend, predicting a potential increase of about 1 °C (34 °F) per day in the coming months as part of a typical heating-cooling cycle observed at Ruapehu.
Monitoring indicators remain consistent with a low level of volcanic activity. As a result, the Volcanic Alert Level remains at 1. The Aviation Color Code remains Green.
Ruapehu Volcano, located in Tongariro National Park, is New Zealand’s most active volcano. It is characterized as a complex stratovolcano formed over 200 000 years through at least four significant cone-building episodes.
It features a predominantly andesitic massif with a volume of 110 km3 (26 miles3), surrounded by a 100 km3 (24 miles3) ring plain of volcaniclastic debris.
Historically, the volcano has experienced a series of subplinian eruptions from around 22 600 to 10 000 years ago. In contrast, frequent mild-to-moderate explosive eruptions have been recorded at its Te Wai ā-Moe (Crater Lake) vent, which likely formed about 3 000 years ago.
Lahars from the crater lake pose hazards to nearby ski areas and river valleys. Ruapehu is within a subduction zone with 14 residents within 5 km (3 miles), 298 within 10 km (6 miles), and 119 709 within 100 km (62 miles).
The volcano’s location within a UNESCO World Heritage site stresses its geological and cultural significance.
References:
1 Minor volcanic unrest continues at Mt Ruapehu as lake temperature slowly increases. Volcanic Alert Level remains at 1. – Geonet – October 31, 2024
2 Geological summary for Ruapehu – GVP – Accessed November 1, 2024
Harsha Borah is an experienced content writer with a proven track record in the industry. Harsha has worked with LitSpark Solutions and Whateveryourdose, honing skills in creating engaging content across various platforms. A gold medalist in a state-level writing competition organized by Assam Tourism, Harsha’s travelogue on Tezpur was widely appreciated. Harsha’s article, "The Dark Tale of the Only Judge in India to Be Hanged," ranks second on Google and has garnered over 11 000 views and 8 900 reads on Medium. Outside of writing, Harsha enjoys reading books and solving jigsaw puzzles.
Commenting rules and guidelines
We value the thoughts and opinions of our readers and welcome healthy discussions on our website. In order to maintain a respectful and positive community, we ask that all commenters follow these rules.