Characterizing the Relation Between Interannual Streamflow Variability and Glacier Cover
A new study confirmed the theory that streamflow variability is dependent on relative glacier cover. From the abstract: “Meltwater from glaciers is not only a stable source of water but also affects downstream streamflow dynamics. One of these dynamics is the interannual variability of streamflow. Glaciers can moderate streamflow variability because the runoff in the glacierized part, driven by temperature, correlates negatively with the runoff in the non‐glacierized part of a catchment, driven by precipitation, thereby counterbalancing each other. This is also called the glacier compensation effect (GCE), and the effect is assumed to depend on relative glacier cover. Previous studies found a convex relationship between streamflow variability and glacier cover of different glacierized catchments, with lowest streamflow variability at a certain optimum glacier cover. In this study, we aim to revisit these previously found curves to find out if a universal relationship between interannual streamflow variability and glacier cover exists, which could potentially be used in a space‐for‐time substitution analysis.”
In a new paper published November 28, 2019, in the journal Scientific Reports, a team of researchers has outlined how smoke from fires in the Amazon in 2010 made glaciers in the Andes melt more quickly.
Bushfires raging in Australia have taken their toll on New Zealand’s glaciers. Smoke and dust from the fires drifted across the Tasman Sea and settled on glaciers in New Zealand more than 1,300 miles away. Ash covering glaciers in New Zealand is visible in photos published to Twitter. In the images, the snow and ice appears as a pinkish color.
Australia has experienced a severe bushfire season. At least 18 people have died, over 1,000 homes destroyed, millions of livestock lost, and over 15 million acres of land has burned. The smoke and dust-laden glaciers of New Zealand are representative of the second-order effects of the bushfires in Australia.
The distance the smoke and ash have traveled and the extent to which they have blanketed glaciers in New Zealand speaks to the severity of the Australian bushfires. This coating of smoke and ash poses a significant threat to New Zealand’s glaciers. It settles as black carbon, which darken glaciers’ snow and ice, absorbing heat and contributing to increased rates of melting and extending the melt season.
This week’s Photo Friday features Fox Glacier, one of New Zealand’s most famous glaciers. It is located in the Westland Tai Poutini National Park, among the Southern Alps on the South Island.
Fox Glacier begins at an elevation of over 3000 meters, and descends to a final elevation of just 300 meters above sea level. On its journey from the mountains of the Southern Alps into a temperate rainforest climate right on the coast, Fox Glacier stretches a total length of 13.1 kilometers.
Fox Glacier is a temperate maritime, or “warm glacier,” meaning its ice exists at its melting point of 0°C. This, along with the wide snow accumulation area and steep, narrow tongue of Fox Glacier, makes it extremely responsive to small temperature and mass balance changes.
From 1983 to 2008, New Zealand experienced a cluster of cold years, influenced by short-term natural climate variability. Of New Zealand’s 3,000+ glaciers, Fox Glacier was one of 58 that advanced in this time period.
From 2009 to the present, however, Fox Glacier––along with a majority of New Zealand’s glaciers––has entered a period of significant retreat. In 2017, the glacier’s length was the shortest it had ever been in recorded history, and this trend is expected to continue for the foreseeable future.
Fox Glacier, along with neighboring Franz Josef Glacier, is one of the world’s most easily accessible glaciers, and is a popular tourist attraction. Both Fox and Franz Josef feature iconic, magnificently sculpted blue ice caves.
As a result of massive retreat in recent years, Fox Glacier now is directly accessible only by helicopter––some 150,000 people a year take these scenic flight tours. On foot, visitors can hike to a scenic overlook, but logistics have limited guided walks to around 80,000 people a year, less than half of what it used to be.
In March 2019, a massive landslide blocked the Fox Glacier access road to both vehicles and pedestrians. In the months following, the small town of Fox Glacier has suffered immensely from the lack of tourism, its primary source of revenue. As of June 21, 2019, access to the road was still closed off.
Glaciers can play an important role in landscape dynamics, interacting with other factors to shape landscape development. Two days after a 7.8 magnitude earthquake struck North Canterbury, New Zealand, a landslide occurred between nearby Fox and Franz Josef glaciers. This landslide could offer insight into the role of glaciers in seismically active areas, particularly concerning the ways in which glaciers interact with earthquake-related instabilities in the landscape.
The landslide occurred at Omoeroa at around 2 p.m. (GMT +12 hours) on November 16th, closing off a section of State Highway 6 along the west coast of South Island for about three hours until debris were cleared.
Earthquakes and landslides are common in New Zealand due to the country’s location on the Pacific Ring of Fire, the area around the Pacific Ocean that is very seismically active. It is so named because of the prevalence of volcanic activity within the ring, which is made up by the major tectonic plate boundaries.
Earthquakes, which occur when Earth’s crust breaks along faults (fractures in the crust), send tremors outwards from the point of breakage. This particular earthquake was caused by oblique-reverse faulting (faulting that had both strike-slip and reverse components) near the boundary of the Pacific and Australian tectonic plates. Landslides, like the one that occurred between the two glaciers, are often triggered by other natural disasters, such as earthquakes or floods. In this case, the earthquake and its aftershocks triggered up to 100,000 landslides, causing local damage and blocking major roads and railway routes.
In conversation with GlacierHub, Umesh Haritashya, an associate professor in environmental geology at the University of Dayton, explained that the region in which the landslide occurred is prone to landslides even without any seismic activity. This is due to the topography of New Zealand’s Southern Alps. As such, it would not be surprising if the earthquake, landslide and glaciers are connected, he said.
While the two glaciers are found on the west coast of South Island, the earthquake occurred on the east coast of the island. The distance between the two suggests that the intensity of the tremors experienced in the area around the landslide may have been quite low. Nonetheless, a link is possible, according to Jeff Kargel, a geoscientist at the University of Arizona. “The timing of this big landslide is certainly suggestive of a direct link to the earthquake,” Kargel told GlacierHub.
“For both direct and circumstantial reasons, earthquakes, glaciers and landslides are closely associated,” Kargel explained. “There is the direct influence of glaciers that produce lots of unstable rock debris over thousands of years, and there are indirect influences, where glaciers erode the mountain topography and produce very steep slopes. These factors create conditions under which seismic activity can easily set off landslides.”
In addition, Kargel noted that glaciers occur where uplift rates have been high and the terrain is elevated to begin with. This means that either circumstantially or indirectly, glaciers and landslides can occur nearby.
Kargel further stated that large earthquakes tend to create instabilities in the landscape that are later exploited by natural processes, making landslides more frequent in the aftermath of earthquakes. “The spike in landslide activity can last for several years,” he said.
In addition to seismic activity, other causes like heavy rain after the earthquake could have contributed to the occurrence of the landslide. New Zealand’s MetService reported that the areas of the glaciers had received considerable rain, with 80-120mm falling the night after the earthquake.
“The West Coast receives an unusually high amount of rain, so slopes are already reconditioned and any seismic activity can trigger major landslides,” Haritashya explained.
The links between the earthquake, glaciers and landslides will become clearer as scientists examine similar events more fully. For now, landslides like these offer an insight into the complex interactions between glaciers, topography and seismic activity. Earthquakes can cause large amounts of disruption to people’s lives, so advancements in this field of science could prove valuable to communities as they seek to address the challenges posed by natural disasters.
While more people are visiting iconic New Zealand glaciers because of concerns that climate change might wipe out the ice masses altogether, visitors are reportedly underwhelmed by the melting, gray glaciers.
This finding is documented in a new multidisciplinary study, “Implications of climate change for glacier tourism,” released last month in Tourism Geographies. The findings were published by Emma J. Stewart and researchers at Lincoln University, in Canterbury, New Zealand, in conjunction with others from neighboring and international universities. The study examines the impacts of climate change on the Fox and Franz Josef Glaciers in New Zealand’s South Island, and how these effects have trickled down to local tourism. The tourism industry there collectively attracted over 500,000 international visitors in 2015.
These glaciers, located in Westland Tai Poutini National Park, are just two of New Zealand’s more than 3,100 glaciers, but they are the country’s most beloved and visited, and have received a flow of tourists dating back to the early 1900s. Their distinctive morphology creates glacier tongues that flow down from the high mountains to low, visitor-accessible elevations.
However, studies show that glacier recession has accelerated at an unprecedented rate in New Zealand. Previous studies estimate that Fox Glacier lost over 700 meters in length between 2008 and 2015, and that neighboring Franz Josef Glacier experienced a similar rate of reduction. Recent modeling estimates that Franz Josef Glacier will shed 62 percent of its current volume by 2100.
In order to explore perceptions of change with regard to glaciers and tourism, the researchers conducted 13 stakeholder interviews with employees from the New Zealand Department of Conservation (DOC) and commercial tourism businesses at the two glaciers. They also administered questionnaires to 500 English-speaking visitors who were returning from guided walks to view Fox or Franz Josef Glacier. Researchers asked visitors about their reasons for journeying to the sites and their overall satisfaction with their glacier visit.
Stakeholders showed widespread agreement that the region’s glacier tourism industry was largely inspired by visitor perceptions of the glaciers as a “bucket list” item or as a “last chance” tourism trip. The notion of “last chance” glacial tourism encapsulates visitors’ desires to observe, photograph, or interact with threatened or rare physical features and natural landmarks. The study suggests that New Zealand’s high levels of glacier tourism are largely due to visitors’ desire to visit these iconic natural landmarks before they disappear.
The study also reveals that stakeholders and tourists alike perceive the glaciers as highly significant to the region and to New Zealand.
“The glaciers are first and foremost the reason why people stop at Franz and Fox,” a DOC employee stressed.
A Franz Josef tourism manager echoed these sentiments, telling his interviewers, “If the glaciers were not here, these towns would not be either.”
“[The glaciers] are hugely significant to New Zealand – culturally, naturally and economically. They are icon destinations on the South Island,” one of the study’s two lead researchers, Emma Stewart of Lincoln University, told GlacierHub in an email.
Yet while stakeholders are in widespread agreement of the glaciers’ importance to the region, and the time-sensitive nature of the possibilities of visiting them, the study’s interviews reveal that visitors are also expressing less wonder at the sight of the once majestic glaciers.
In the survey, one DOC ranger said, “I would feel much better if the glaciers were coming forward, they always look better, whereas now it’s just a dirty old strip of ice up around the corner.”
The study noted that “significant segments of the visitor population” found that their expectation of the size and condition of the glaciers “exceeded the reality.”
On average, 50 percent of interviewed visitors expected the glacier to be “bigger,” 45 percent expected the ice would be “cleaner” and 35 percent thought the glacier would be “more spectacular.” The surveyors noticed that visitor satisfaction often correlated with how high up on the glacier the visitors travel.
The glaciers’ rapid retreats and the resulting increased risk of rockfall hazards have impeded visitor access, particularly higher up on the glacier, and especially on Franz Josef.
Co-author Heather Purdie of the University of Canterbury told GlacierHub via email that guided walks to Franz Josef recently were suspended.
“Guided walks that used to access the glaciers on foot from the lower valley are now no longer possible,” she wrote.
She notes that now, visitors can only participate in a guided walk tour by flying to the glaciers by helicopter. This option’s high price is prohibitive for many visitors, though.
Overall, access is becoming limited. “People cannot get as close to the glacier as they used to,” Purdie continued.
These findings highlight concerns that glacial tourism may decrease with increased glacial melting. One accommodation provider suggested that, “If the glaciers are established enough as a tourist icon then people will come even if it is not like it used to be.” However, the provider then added, “Maybe I am naïve to think that people will still come here without the glacier.”
Yet the study simultaneously argues that perceptions of the “last chance to see” phenomenon of glaciers might simultaneously increase glacial tourism in the region.
The study is the first of its kind to report highly adaptive capacities of glacial tourism stakeholders, such as DOC employees and glacial tourism companies. Among the stakeholders interviewed, the study reported strong evidence of the understanding of biophysical trends and a demonstrated ability to flexibly and successfully facilitate glacial access and glacier product availability and to maintain high levels of visitor satisfaction, by actions such as introducing helicopter rides to survey the glacier and modifying walking tour routes to increase safety and better showcase the glacier as it melts.
The authors hope that Westland Tai Poutini National Park’s case-specific adaptive strategies to adapt their glacial tourism sectors to climate change can extend beyond New Zealand.
“Given that glaciers are retreating globally,” Stewart said. “[The study] has implications for more local, and possibly neighboring glacier experiences, such as the Tasman and Hooker Glaciers in the Aoraki/Mount Cook National Park.”
Close-Up Drone Video of an Erupting Volcano Melts Face off GoPro Camera in Iceland
Director of aerial imaging for drone maker DJI, Eric Cheng, and nature photographer Ragnar Th. Sigurdsson were able to fly a Quadcopter mounted GoPro camera into an active eruption in the Bardarbunga volcanic system, Iceland.
Read the full story here. For more of GlacierHub’s coverage on the recent Icelandic volcano eruption and the effect on nearby glaciers, click here and here.
Jackson Gallagher’s Glacier Fiasco
Actor Jackson Gallagher star of the Australian television soap opera, “Home and Away”, and three other climbers were forced to run for their lives when rocks came falling down above them on top of the Franz Josef glacier in New Zealand.
Chile’s San Quintín Glacier Viewed from Space
Melting into a lake full of glacier-churned ‘rock flour,’ Chile’s San Quintín glacier can be seen emptying into the Northern Patagonian Ice Field in a recent satellite photo.