Tiny glacier bears discovered in New Zealand

Polish scientist Krzysztof Zawierucha has discovered bears hiding in the snow of New Zealand’s glaciers. More specifically, he and his colleagues have described two new genera of Tardigrades living in the glaciers of the Southern Alps. Tardigrades, also known as water bears, are short fat eight legged animals usually overlooked because they are less than a millimetre long. Tardigrada is a sub classification of the Animalia kingdom (the equivalent sub-classification for humans is called Chordata, then the Mammalia class, the Primate order, the Hominidae family, the Homo genus, and finally the Homo sapiens species).

Krzysztof and colleagues collected snow samples from near the top of the Fox, Franz and Whataroa glaciers. When they melted and filtered out the water and looked at the residue under a microscope, staring right back at them were some Tardigrades (or some equivalent of staring, as they didn’t have eyes). Krzysztof, who is a Tardigrade expert, didn’t recognise the species, or even the genus. After careful consideration of their size and body parts Krzysztof figured out that he was looking at two new genera. One was peculiar for its combination of dark colour, stumpy claws, and big mouth. Krzysztof thought the dark colour could be an adaptation to the high ultra-violet radiation conditions on the snow surface. Similar colouring is found in Tardigrade that live in Central Asian glaciers, so it might be considered an example of parallel evolution. He gave the new genera the name Kopakaius, a latinised version of kōpaka, the Māori word for glacier. He gave the specific species (he only had the one example) the full name Kopakaius nicolae where nicolae is a reference to his wife Nicoletta.

A close-up view of the newly described “water bear” Kopakaius nicolae found in snow on the Fox, Franz and Whataroa glaciers. The scale bar is in micrometres, so the whole bear is about 1 mm long.

The second genera of Tardigrades he called Kararehius, a latinised version of kararehe, the Māori word for animal. This one was transparent and had an unusual combination of stomach sections and claw cuticles. Krzysztof named the species they had collected  Kararehius gregorii where gregorii is a reference to his father Grzegorz.

A close-up view of the newly described “water bear” Kararehius gregorii found in snow on the Fox, Franz and Whataroa glaciers. The scale bar is in micrometres, so the whole bear is about 0.5 mm long.

DNA analysis of the bears confirmed their differences from other Tardigrade in the world but the two genera he found were not as different as the body shapes had first indicated. The DNA analysis found that the Kopakaius nicola bears from the Whataroa glacier were genetically distinct from those found on the Fox and Franz Josef glaciers. Krzysztof argues the differences may be associated with the isolation of populations as the previously-connected glaciers have separated into independent units.

Next time you are up in the glaciers, tread carefully and keep a watch out for bears.

NIWA Snow and Ice Network Information Available

NIWA have started publishing graphs of the snow depth at ten of it’s snow and ice network (SIN) weather stations.

This is a major development. The network was installed about 12 years ago but access to the snow-depth information has to-date been by request only.

The information is published as graph images at https://niwa.co.nz/freshwater-and-estuaries/research-projects/snow-and-ice-network

The graphs don’t provide a scale on the snow-depth axes, but an average line on the graphs means it is possible to see how the current year’s snow depth is progressing in a relative way.

For reference average peak snow depth at Mueller is about 2.5 m, and at Mahanga and Mt Larkins it is about 70 cm.

If an avalanche occurs in the mountains and there is no one to hear it, does it make a sound?

Yes it does. And that sound can be used to count, measure and map avalanches. Leighton Watson from the University of Oregon in the USA, with colleagues, has tested a system of using microphone arrays to detect and characterise avalanches falling on to the Milford Road. They installed two sets of “infrasound” sensors near the Homer Tunnel in September 2020. The very next day the Waka Kotahi’s Milford Road Alliance triggered seven large avalanches in the area by dropping explosives from helicopters onto the mountain snow pack. Leighton’s microphones clearly recorded the sound of the avalanches. In fact the sounds were stronger than had been recorded anywhere else in the world. Through cunning trigonometry of the arrival time of the sound at the different microphones, Leighton was able to track and map where the avalanches were occurring. His maps were validated by the observations of the Milford Road Alliance avalanche team. The microphones were left in place for a month and continued to collect avalanche sound data, including naturally occurring night time avalanches. In each case the avalanche location was mapped. Current avalanche risk assessment relies on incomplete avalanche occurrence data, as observation techniques rely on human observation of events or debris. This is problematic in remote regions or during low visibility in storms or at night. Leighton and his colleagues have demonstrated a new approach which could improve avalanche frequency knowledge and make our mountains safer.

Watson, L.M., Carpenter, B., Thompson, K., Johnson, J.B., 2021. Using local infrasound arrays to detect plunging snow avalanches along the Milford Road, New Zealand (Aotearoa). Nat Hazards. https://doi.org/10.1007/s11069-021-05086-w

A last view of the North Island glaciers

Possibly the most viewed glaciers in New Zealand are those on Mt Ruapehu. Everybody who drives, flies or takes a train past this largest of the North Island volcanoes cannot help but have their eye drawn to its ice clad summits. Its quite likely that many of us are unaware that what we are seeing are the last remnants of great ice bodies that have persisted for 50 thousand years.

To help explain the special case of Mt Ruapehu glaciers, Shaun Eaves and Martin Brook have published a comprehensive review of glaciers and glaciation of the North Island in the New Zealand Journal of Geology and Geophysics.

Fourteen glaciers grace the slopes of Mt Ruapehu and represent the last of the North Islands glaciation. In the past glaciers provided extensive cover over Mts Ruapehu and Tongariro, were probably on the slopes of Taranaki and some remote basins in the Tararua Ranges and perhaps on the tops of the Kaimanawa Ranges and a niche or two in the Ruahine Ranges.

The review highlights the unique volcanic location of the Ruapehu glaciers. The glacier’s inter-twining, sometimes literally, with the area’s volcanism provides valuable age markers to assist with glacier extent aging. No other glacierised region of New Zealand has this feature.

For all the great glacier-volcanic interaction, the review has come too late for the Whakapapa Glacier. The review describes how in the 1950s the glacier flowed 1.5 km from the edge of the mountain’s summit plateau down to the slopes of New Zealand’s largest ski field. Since then it has retreated, split into two and is now nothing but a snow patch that, in some summers, leaves nothing to see.

The demise of the Whakapapa glacier appears to be the first of many as the theme of retreat and thinning is common to nearly all the mountain’s glaciers. The review suggests that next few decades are predicted to be the last for most of the remaining 14 North Island glaciers.

It might be wise to take an extra look at the white capped mountain this summer when you next drive/fly/train past. It just may be your last chance before the end of the glacial life of the North Island.

We’ve lost 216 glaciers!

Sabine Baumann from the Technical University of Munich has just finished counting New Zealand’s glaciers and found that we are missing 216 of them. Sabine carefully counted every independent area of ice larger than 1 hectare, even those bits of ice hidden under rock.

In total 2918 glaciers were found, but in 1978 there had been 3134. It seems that 216 glaciers have melted away.

The total area of glacier has shrunk by 364 km2 , that is a about the size of Manakau Harbour.

Just 15 of the glaciers were in the North Island (all on Mt Ruapehu), three less than the 1978 count.

The new glacier inventory has been published in the Journal of Glaciology

The 1978 effort was undertaken by Trevor Chinn and was published in 2001 in the Journal of Hydrology (NZ).

2021 SIRG Meeting dates

Keep the 9th to 13th February free in your calendars.

For 2021 the New Zealand Snow and Ice Research Group will join with Antarctica New Zealand for a combined meeting in Christchurch at the University of Canterbury.

The current plan is to have the snow and ice themed presentations on Thursday the 11th and Friday the 12th of February.

There will also be a one day field trip at the end (Sat 13th) for those keen to explore glacier-climate in the Canterbury high-country.

The official meeting web page is being hosted by Antarctica NZ with a link to it from the SIRG web page

So keep those dates secured in your diaries, updates coming soon!

Listen to millennial-scale glaciation

Hamish Prince, a post-graduate student in the School of Geography at the University of Otago, has put together a musical interpretation of the ‘Millennial-scale pulsebeat of glaciation in the Southern Alps of New Zealand’ (Strand et al., 2019).

This lets you listen to the (asynchronous) relationship between cold periods in the Northern and Southern hemisphere over the last 50,000 years.

In a review of Strand et al., 2019, it was suggested that if North Atlantic cold periods were a jazz rhythm, New Zealand’s glaciers accent the back beat. To explore the potential ‘anti-phased timing’ Hamish created a drum beat using the timing of both events, ordered from oldest to most recent. The timing of Northern Hemisphere cold periods were standardized and used to define the bars in the music. The position of New Zealand glacier advances were then placed in the music relative to these. A four bar rhythm appeared from the data and from this Hamish wrote a short composition. This lets you listen to the (asynchronous) relationship between cold periods in the Northern and Southern hemisphere from the last 50,000 years.

Such link in the rhythm of the North Atlantic cold periods and the Lake Pukaki moraine dates suggest some sort of a connection between New Zealand and Northern Hemisphere glacial fluctuations over the last 50,000 years.

New Zealand glaciers play reggae.

If the jazz rhythm of cold climate is defined by North Atlantic iceberg activity, then New Zealand’s glaciers accent the back beat.
That is the finding of Peter Strand and collaborators as described in their recent paper in Quaternary Science Reviews.
The signature beat of Northern Hemisphere cold periods during the last glacial period (since about 90,000 years ago) are known as Heinrich events.
Hartmut Heinrich found layering of rock sediment on the bed of the Atlantic that wasn’t local. It had arrived by iceberg transport. Dating when each of these layers of foreign rocks were deposited provided a good indication of when the Northern Hemisphere was cold. Other efforts to date Northern Hemisphere cold periods aligned well to Heinrich’s rock layer dates, so his name has been associated with these cold Northern Hemisphere events.

When considering the current rapid change in global temperatures, it is not unreasonable to look to the past to see how temperature changes were manifest.
One point of interest is whether there is synchronisation of Northern and Southern Hemisphere temperatures.
The lines of rock on the hillsides above New Zealand’s Lake Pukaki represent past extents of a former glacier. Peter Strand and his colleagues found that each rock-line was deposited by the glacier at different times during the last glacial period.
If the Northern and Southern hemisphere temperatures were synchronised, then the dates of these moraines should align with the Heinrich events.
They don’t.
The dates of these moraines fall between the Heinrich events. It seems that when the Northern Hemisphere was cold, The Pukaki glacier was in retreat, and when the Northern Hemisphere was warm, the Pukaki glacier advanced to build these moraines.

 

Trevor Chinn 1938 – 2018

It is with great sadness that the New Zealand branch of the International Glaciological Society and the wider snow and ice research community acknowledge the passing of Dr Trevor Chinn.
Trevor died yesterday morning (20th December 2018) following a recent stroke.

Trevor was an integral part of snow and ice research in New Zealand for over 50 years. His knowledge of the New Zealand and Antarctica cryosphere was immense, he had an impressive publication record, and undoubtedly, the best known knowledge of glaciers large and small across the entire Southern Alps. His passion for the mountains, and drive to better understand snow and ice processes, meant that Trevor spent many hours in the field. He was a key player in the initiation of New Zealand’s first glacier mass balance programmes on Tasman and Ivory Glaciers, and later pioneered the end-of-summer snowline monitoring programme, which has evolved to one of the most comprehensive glacier data sets in the Southern Hemisphere. Trevor had an energy and spark that was contagious. He loved to engage with students and delighted in encouraging the next generation of scientists – especially with a cheeky challenge to their hypothesis or interpretation.

Trevor’s outgoing personality meant that he was not only good at doing science but great at communicating science. He was the go-to person for media and education. His ability to take complex scientific processes and explain them to a general audience was legendary, especially the way his animated explanations were often accompanied by one of his original glacier-cartoons!

Trevor was awarded a Doctor of Science from the University of Canterbury in 2007, having completed a Masters in Geology there back in 1975.

In 2016, in recognition of his outstanding service and contribution to glaciological research in New Zealand and Antarctica, the International Glaciological Society awarded Trevor with the prestigious Richardson Medal.

Our hearts and thoughts go out to Trevor’s family and friends, and to all those whom this ‘glaciologist- extraordinaire’ touched during his amazing life.

A memorial service is being planned to celebrate Trevor’s life in the New Year. We will provide details of this nearer the time.