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AbruptSLR

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New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« on: August 10, 2014, 01:01:10 PM »
The following link leads to a web article focused on the glacial volume loss (the first attached image shows the loss since 1977) from New Zealand's Southern Alps going back to the 1890's, with a comparison to the global glacial volume loss (see the second image):

http://www.businessspectator.com.au/article/2014/7/29/science-environment/nzs-southern-alps-have-lost-third-their-ice

Extracts: "A third of the permanent snow and ice of New Zealand’s Southern Alps has now disappeared, according to our new research based on National Institute of Water and Atmospheric Research aerial surveys.
Since 1977, the Southern Alps’ ice volume has shrunk by 18.4 km3 or 34%, and those ice losses have been accelerating rapidly in the past 15 years."

"Martin Hoelzle and associates at the World Glacier Monitoring Service have estimated estimate the 1890s extent of ice volume in New Zealand’s Southern Alps was 170 km3, compared to 36.1 km3 now. That disappearance of 75-80 per cent of Southern Alps ice is graphic evidence of the local effects of global warming."

Caption for the first image: "The Southern Alps’ total ice volume (solid line) and annual gains or losses (bars) from 1976 to 2014 in km3 of water equivalent, as calculated from the end-of-summer-snowline monitoring programme.”

Caption for the second image: "Global Glacier Thickness Change: This shows average annual and cumulative glacier thickness change of mountain glaciers of the world, measured in vertical metres, for the period 1961 to 2005. (Mark Dyurgerov, Institute of Arctic and Alpine Research, University of Colorado, Boulder, CC BY)"

« Last Edit: August 10, 2014, 07:25:13 PM by AbruptSLR »
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AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH, Glaciers
« Reply #1 on: August 10, 2014, 07:24:41 PM »
As almost all of the threads in this folder focus on Northern Hemisphere glacier, I thought that I would expand this thread to include other Southern Hemisphere (and some tropical) glaciers.

Although over a year old, the following linked reference, with a free access pdf, documents the acceleration in glacial ice melt loss from the tropical Andes since the 1970's (due to climate change):

Rabatel, A., Francou, B., Soruco, A., Gomez, J., Cáceres, B., Ceballos, J. L., Basantes, R., Vuille, M., Sicart, J.-E., Huggel, C., Scheel, M., Lejeune, Y., Arnaud, Y., Collet, M., Condom, T., Consoli, G., Favier, V., Jomelli, V., Galarraga, R., Ginot, P., Maisincho, L., Mendoza, J., Ménégoz, M., Ramirez, E., Ribstein, P., Suarez, W., Villacis, M., and Wagnon, P., (2013), "Current state of glaciers in the tropical Andes: a multi-century perspective on glacier evolution and climate change", The Cryosphere, 7, 81-102, doi:10.5194/tc-7-81-2013, DOI: 10.5194/tc-7-81-2013

http://www.the-cryosphere.net/7/81/2013/tc-7-81-2013.html

Abstract: "The aim of this paper is to provide the community with a comprehensive overview of the studies of glaciers in the tropical Andes conducted in recent decades leading to the current status of the glaciers in the context of climate change. In terms of changes in surface area and length, we show that the glacier retreat in the tropical Andes over the last three decades is unprecedented since the maximum extension of the Little Ice Age (LIA, mid-17th–early 18th century). In terms of changes in mass balance, although there have been some sporadic gains on several glaciers, we show that the trend has been quite negative over the past 50 yr, with a mean mass balance deficit for glaciers in the tropical Andes that is slightly more negative than the one computed on a global scale. A break point in the trend appeared in the late 1970s with mean annual mass balance per year decreasing from −0.2 m w.e. in the period 1964–1975 to −0.76 m w.e. in the period 1976–2010. In addition, even if glaciers are currently retreating everywhere in the tropical Andes, it should be noted that this is much more pronounced on small glaciers at low altitudes that do not have a permanent accumulation zone, and which could disappear in the coming years/decades. Monthly mass balance measurements performed in Bolivia, Ecuador and Colombia show that variability of the surface temperature of the Pacific Ocean is the main factor governing variability of the mass balance at the decadal timescale. Precipitation did not display a significant trend in the tropical Andes in the 20th century, and consequently cannot explain the glacier recession. On the other hand, temperature increased at a significant rate of 0.10 °C decade−1 in the last 70 yr. The higher frequency of El Niño events and changes in its spatial and temporal occurrence since the late 1970s together with a warming troposphere over the tropical Andes may thus explain much of the recent dramatic shrinkage of glaciers in this part of the world."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #2 on: August 10, 2014, 07:40:11 PM »

The following linked reference verifies that the accelerating melting of the world's largest tropical glacier, Peru's Qori Kalis outlet glacier is related to increasing temperatures rather that due to reduced precipitation (and correlated this trend with other glaciers worldwide, including other Southern Hemisphere glaciers):


Justin S. Stroup, Meredith A. Kelly, Thomas V. Lowell, Patrick J. Applegate and Jennifer A. Howley, (2014), "Late Holocene fluctuations of Qori Kalis outlet glacier, Quelccaya Ice Cap, Peruvian Andes", Geology, doi: 10.1130/G35245.1


http://geology.gsapubs.org/content/early/2014/02/24/G35245.1.abstract


Abstract: "The temporal and spatial patterns of late Holocene climate conditions provide valuable information for testing hypothesized mechanisms of recent climate changes. As a proxy for late Holocene climate in the southern tropics, we present a 10Be chronology of moraines deposited by Qori Kalis, an outlet glacier of Quelccaya Ice Cap in Peru. The Qori Kalis moraines are located downflow from the Quelccaya ice cores and provide the first glacial extent record that can be compared directly to annually resolved tropical ice core records. Qori Kalis advanced to its late Holocene maximum extent prior to 520 ± 60 yr before CE 2009, when Quelccaya ice core net accumulation values were at or below their late Holocene average. Subsequent glacial retreat between ∼520 and 330 yr before CE 2009 coincides with the highest net accumulation values of the ∼1800-yr-long ice core record. Therefore, we suggest that temperature, rather than net accumulation, was the primary driver of these glacial fluctuations. Comparison of the late Holocene fluctuations of Qori Kalis glacier with glaciers in the southern tropical Andes, Patagonian Andes, Switzerland, Alaska, and New Zealand suggests globally synchronous, centennial-scale cold events."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #3 on: August 10, 2014, 08:03:50 PM »
In the linked 2011 reference the researchers found that 270 of the largest glaciers between Chile and Argentina have melted “10 to 100 times” faster in the past 30 years than they have during any period since 1650.


N. F. Glasser, S. Harrison, K. N. Jansson, K. Anderson & A. Cowley, (2011), " Global sea-level contribution from the Patagonian Icefields since the Little Ice Age maximum", Nature Geoscience , 4, pp303 - 307
 doi:10.1038/ngeo1122

http://www.nature.com/ngeo/journal/v4/n5/pdf/ngeo1122.pdf

Abstract: "The melting of mountain glaciers and ice caps is expected to contribute significantly to sea-level rise in the twenty-first century, although the magnitude of this contribution is not fully constrained. Glaciers in the Patagonian Icefields of South America are thought to have contributed about 10% of the total sea-level rise attributable to mountain glaciers in the past 50 years. However, it is unclear whether recent rates of glacier recession in Patagonia are unusual relative to the past few centuries. Here we reconstruct the recession of these glaciers using remote sensing and field determinations of trimline and terminal moraine location. We estimate that the North Patagonian Icefield has lost 103±20.7 km3 of ice since its late Holocene peak extent in AD 1870 and that the South Patagonian Icefield has lost 503±101.1 km3 since its peak in AD 1650. This equates to a sea-level contribution of 0.0018±0.0004 mm yr−1 since 1870 from the north and 0.0034±0.0007 mm yr−1 since 1650 from the south. The centennial rates of sea-level contribution we derive are one order of magnitude lower than estimates of melting over the past 50 years, even when we account for possible thinning above the trimline. We conclude that the melt rate and sea-level contribution of the Patagonian Icefields increased markedly in the twentieth century."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #4 on: August 15, 2014, 05:36:22 PM »
The following linked reference demonstrates that global glacier mass loss is accelerating due to recent anthropogenic forcing above the extant natural component:


Ben Marzeion, J. Graham Cogley, Kristin Richter, & David Parkes, (2014), "Attribution of global glacier mass loss to anthropogenic and natural causes", Science DOI: 10.1126/science.1254702


http://www.sciencemag.org/content/early/2014/08/13/science.1254702


Abstract: "The ongoing global glacier retreat is affecting human societies by causing sea-level rise, changing seasonal water availability, and increasing geohazards. Melting glaciers are an icon of anthropogenic climate change. However, glacier response times are typically decades or longer, which implies that the present-day glacier retreat is a mixed response to past and current natural climate variability and current anthropogenic forcing. Here, we show that only 25 ± 35% of the global glacier mass loss during the period from 1851 to 2010 is attributable to anthropogenic causes. Nevertheless, the anthropogenic signal is detectable with high confidence in glacier mass balance observations during 1991 to 2010, and the anthropogenic fraction of global glacier mass loss during that period has increased to 69 ± 24%."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Clare

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #5 on: January 04, 2015, 02:56:20 AM »
Newspaper article (+ a link in it to a NYT one) about the economic impact of glacial retreat on NZ's West Coast. There is a significant tourist industry associated with this pair of glaciers, which this year have now retreated so far up their valleys as to become inaccessible by foot:
http://www.stuff.co.nz/environment/64643146/plight-of-new-zealand-glaciers-is-global-news


AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #6 on: January 27, 2015, 07:35:45 PM »
The linked article discusses how global warming will rapidly degrade tropical glaciers in the Andes:

http://www.theguardian.com/science/2015/jan/27/global-warming-glacier-depletion-andes
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AbruptSLR

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #7 on: February 10, 2015, 08:37:16 PM »
The linked article discusses the influence of air pollution from 16th century silver mines on glaciers in the Andes:

http://www.csmonitor.com/Science/2015/0210/Andean-ice-cap-yields-signs-of-16th-century-pollution
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Clare

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LRC1962

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #9 on: March 05, 2015, 06:17:55 PM »
The linked article discusses how global warming will rapidly degrade tropical glaciers in the Andes:

http://www.theguardian.com/science/2015/jan/27/global-warming-glacier-depletion-andes
A consequence can be seen in the article. Chacaltaya Glacier, Bolivia
Quote
La Paz and the neighboring city of El Alto, Bolivia, compose one of the fastest-growing urban areas in Latin America.2,3 La Paz, the world's highest capital city, depends on runoff from Andean glaciers for around 30 percent of its water supply.2,4
That is just one of the cities in the high Andeas and all of them are in the same situation. BTW Pop of La Laz is around 800,000.
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Clare

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #10 on: March 23, 2015, 06:12:54 AM »
Frans Josef glacier, New Zealand

Article with spectacular Youtube clip link below.
http://tvnz.co.nz/national-news/incredible-drone-footage-shows-franz-josef-glacier-s-retreat-6264180


Tor Bejnar

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #11 on: March 23, 2015, 04:05:52 PM »
In December 1977 I hitch hiked (via motorcycle from the coast!) to the toe of Frans Josef Glacier and walked on some beautiful blue ice.  Without hobnails or cleats, footing was rather precarious!

Image from the internet shows approximate extent then.  Curious that this glacier advanced from 1985 to 2006.
http://www.teara.govt.nz/en/photograph/10735/franz-josef-glacier-advances-and-retreats
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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #12 on: March 23, 2015, 04:26:05 PM »
Tor, a lot of the Norwegian glaciers in the West (lots of precipitation) expanded as well around 2000. Likely explanation is the increased snowfall from a warmer climate, but that doesn't help a decade or so later when much of that snow falls as rain.
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pileus

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #13 on: August 08, 2017, 11:38:06 AM »
Loong time since this thread was active, here's an update on Peru's tropical glaciers.  Elements of "places less liveable" and "tsunamis/landslides from glacier collapse" in this write up as well.

A flood of problems
Peru’s glaciers have made it a laboratory for adapting to climate change. It’s not going well.

http://www.washingtonpost.com/sf/world/2017/08/07/perus-glaciers-have-made-it-a-laboratory-for-adapting-to-climate-change-its-not-going-well/?hpid=hp_hp-top-table-main_peruglaciers-911pm-winner%3Ahomepage%2Fstory&utm_term=.6db060a2029e

LAKE PALCACOCHA, Peru

After a day of bright sunshine, a chunk of ice the size of a dump truck broke off the glacier on Mount Pucaranra a few weeks ago. It plunged into the lake below and kicked up a wave nine feet high.

Victor Morales, a small, catlike man with a tattered ski cap who is the lake’s solitary watchman, scrambled up to a stone hut on the side of the mountain and got on the radio. The wave had damaged an emergency drainage system meant to reduce the volume of the lake. But to his great relief, the earthen dam holding back the water was intact.

“It wasn’t a big avalanche,” Morales said.

Lake Palcacocha is a mile long and 250 feet deep, and the effect of a large avalanche would be similar to dropping a bowling ball in a bathtub. Modeling scenarios predict a 100-foot wave so powerful it would blow out the dam. Three billion gallons of ice water would go roaring down the mountain toward the city of Huaraz, burying its 200,000 residents under an Andean tsunami of mud, trees and boulders.

Lake Palcacocha is an example of the immediate threats Peru and other developing countries are facing from climate change. The country is especially vulnerable since it is home to 70 percent of the world’s “tropical glaciers” — small, high-altitude ice caps found at the earth’s middle latitudes. Their disappearance has made Peru something of a laboratory for human adaptation to climate change.

budmantis

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #14 on: September 17, 2017, 05:16:41 AM »
Pileus:

Thanks for the post. I was perusing topics I seldom follow and found your entry most interesting!.

BudM

vox_mundi

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #15 on: February 09, 2019, 12:27:41 AM »
Tasman Glacier: Huge Ice Chunks Break Off New Zealand Glacier 
https://www.bbc.com/news/world-asia-47171009



Huge chunks of ice have broken off the Tasman Glacier, New Zealand's largest.

They have filled up at least a quarter of the meltwater lake at the foot of the glacier in the Aoraki/Mount Cook National Park, reports say.

The lake started to form in the 1970s as the glacier rapidly retreated - a phenomenon thought to have been largely caused by global warming.

One guide says the chunks resemble huge skyscrapers lying on their side in the water.

https://en.m.wikipedia.org/wiki/Tasman_Glacier

The falling ice chunks led to some "chaos" on the water, Anthony Harris, a guide at Southern Alps Guiding, told the stuff New Zealand website.

A tidal surge up to two metres (6.5ft) high damaged a lake jetty and lifted a boat trailer upside down onto another trailer, Mr Harris said.

"All in all, this is the most significant event I've seen in the last five years on the Tasman."



https://i.stuff.co.nz/national/110448731/large-chunks-of-ice-break-from-tasman-glacier-on-west-coast-of-south-island
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pietkuip

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #16 on: January 02, 2020, 02:07:21 PM »
Photos that show how brown they get from the fires in Australia.

"one expert saying the incident could increase glacier melt this season by as much as 30%."

https://www.theguardian.com/world/2020/jan/02/new-zealand-glaciers-turn-brown-from-australian-bushfires-smoke-ash-and-dust

KiwiGriff

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #17 on: March 06, 2020, 08:04:55 PM »
Pink frosting on south island glaciers from Australian bush fires .

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KiwiGriff

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #18 on: August 08, 2020, 08:27:16 PM »
'There’s still a choice': New Zealand's melting glaciers show the human fingerprints of climate change
 The study looked at changes to 10 of the country’s glaciers after scientists noticed significant loss of snow during monitoring flights.
New research has found extreme melting of the country’s glaciers in 2018 was at least ten times more likely due to human-caused global heating
Quote
Twice a year, glaciologist Lauren Vargo and her colleagues set up camp beside two small lakes close to New Zealand’s Brewster glacier. Each time the trek to carry the measuring stakes takes a little bit longer as the glacier’s terminus gets further away.

Dr Vargo, a native of Ohio now working at the Antarctic Research Centre at the Victoria University of Wellington, is studying New Zealand’s glaciers from the air and on the ice.

New research just published in the journal Nature Climate Change has found that extreme melting of the country’s glaciers in 2018 was at least ten times more likely to have happened because of human-caused global heating.

Loss of ice across New Zealand’s glaciers in 2011, which was another extreme melt year, was six times more likely because of the planet’s warming, the study found, caused by an accumulation of greenhouse gases in the atmosphere mostly from burning fossil fuels.

Vargo, the lead author of the study, told the Guardian: “As scientists we know that theoretically warm temperatures should melt ice, but the goal of the research was to formally show that link between melting and climate change.”
Graham Readfearn
https://www.theguardian.com/environment/2020/aug/04/theres-still-a-choice-new-zealands-melting-glaciers-show-the-human-fingerprints-of-climate-change

Anthropogenic warming forces extreme annual glacier mass lossLauren J. Vargo1,2 ✉, Brian M. Anderson1, Ruzica Dadić1, Huw J. Horgan 1,2, Andrew N. Mackintosh3, Andrew D. King 4 and Andrew M. Lorrey5
Quote
Glaciers are unique indicators of climate change. While recent global-scale glacier decline has been attributed to anthropogenic forcing, direct links between human-induced climate warming and extreme glacier mass-loss years have not been documented. Here we apply event attribution methods to document this at the regional scale, targeting the highest mass-loss years (2011 and 2018) across New Zealand’s Southern Alps. Glacier mass balance is simulated using temperature and precipitation from multiple climate model ensembles. We estimate extreme mass loss was at least six times (2011) and ten times (2018) (>90% confidence) more likely to occur with anthropogenic forcing than without. This increased likelihood is driven by present-day temperatures ~1.0 °C above the pre-industrial average, confirming a connection between anthropogenic emissions and high annual ice loss. These results suggest that as warming and extreme heat events continue and intensify, there will be an increas-ingly visible human fingerprint on extreme glacier mass-loss years in the coming decades.
https://www.nature.com/articles/s41558-020-0849-2.epdf
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morganism

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #19 on: April 15, 2022, 11:29:09 PM »
The Zealandia Switch drove rapid global ice retreat 18,000 years ago. Has it switched to a new level?

"A new mechanism that explains a rapid shift at the end of the last ice age – called the Zealandia Switch – is founded on New Zealand moraine evidence. This new hypothesis is challenging a long-held view about why glaciers changed in the recent and distant past.

While the Zealandia Switch focuses on global ice retreat for prehistoric times, we think it may also explain what is happening right now with our glaciers.

snip:
Glacial geologists use rare chemical isotopes trapped in rocks to trace the history of Earth’s surface with a technique called cosmogenic surface exposure dating.

This method measures how long rocks found on the surface today have been exposed to cosmic rays. Boulders that have been carried inside flowing ice have zero exposure history.

When they are dropped onto a moraine and exposed to cosmic rays from outer space, their “cosmic clock” starts and the rare isotopes begin to accumulate inside minerals in the rock.

Once exposure dates for moraine boulders are established, they are linked to detailed maps that outline ice advance and retreat sequences."
snip:
When the Zealandia Switch turns on and spins up the southern westerlies, it helps to promote water vapour export from the tropics and atmospheric circulation patterns that drive warming in both hemispheres. If the Zealandia Switch hypothesis is upheld, then the story about Quaternary ice age origins and their impacts on global climate, plant ecosystems and ancient fauna will need to be rewritten.

https://theconversation.com/the-zealandia-switch-drove-rapid-global-ice-retreat-18-000-years-ago-has-it-switched-to-a-new-level-179188

kassy

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #20 on: April 16, 2022, 07:45:39 PM »
Quote
Offshore in the Tasman Sea, microfossils from sediment cores indicate ocean currents and boundaries shifted at exactly the same time. Climate modelling can explain the simultaneous land and sea changes through a major switch of Southern Hemisphere westerly winds over the nearly-submerged Zealandia continent – hence the Zealandia Switch hypothesis.

That seems rather solid evidence.

Not good for the glaciers and who knows what other mechanisms we will trigger.
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Sebastian Jones

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #21 on: April 17, 2022, 06:24:05 AM »
Zealandia Switch?
Hmmmmmm.
Yes clearly and uncontroversially the climate began warming (relatively) fast after the Last Glacial Maximum, around 18k yrs BP.
But was the evidence described above the cause or the effect of the warming? Similarly now- we know we are warming even more rapidly than the fastest warming as we came out of the last glaciation, so is the evidence of the Zealandia Switch that we see now a result or a cause?
Everything I have learned to date about climate cycles is that they are driven by perturbations in the earth's orbit (Milankovitch cycles) and changes in CO2 in the atmosphere.
I'd really like for some of the climate experts on the forum to weigh in- probably in a different thread.....

kassy

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #22 on: April 17, 2022, 06:35:43 PM »
It is a local mechanism which happens under certain conditions which are driven by what happens on a global scale so it is caused by the usual suspects you mention. Although there is a twist.

It is hard to find patterns of weather shifts in geological data especially if you go way back in time.
For recent history we can combine lots of resources like dendrochronology and lake sediments. The Southern Hemisphere data is much more sparse so the microfossils really help.

The twist:

Quote
These connections raise the possibility that human activities have flicked the Zealandia Switch to a higher level of the “ON” position, and it may remain stuck there for the foreseeable future. If what unfolds is anything similar to when the Zealandia Switch curtailed the ice age during the Last Glacial Termination, we can expect big, fast and global climate re-organisation impacts.

So there is clear evidence for a strong switch in the past and data at something similar occurring now.

The relevant part is that the big lack in climate models is the clouds. Most of our historical data comes from what used to be the normal climate but we are outside that boundary already (every year is about 1,2 warmer then normal).

If the historical Switch is legit the climate model needs to be able to reproduce it with proper historical input. Once it does that we should of course run it with recent historical input and see where this takes us.

The authors are the head of NIWA and 4 other professors.
Not so sure about the claim in the last paragraph of the article it's too strong or it needs a whole lot of extra explanation.
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kassy

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Re: New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« Reply #23 on: April 22, 2022, 09:26:44 AM »
Frozen no more: Indonesia’s only tropical glacier could melt away as soon as 2025

JAKARTA: Primary school students in Indonesia are taught that the country has something significant, a tropical glacier in Papua’s Jayawijaya mountains which is the only one in the region.

Located at Jaya summit or Puncak Jaya in the Indonesian language, some people call it the Eternity Glacier.

However, in a few years, teachers may not be able to tell their students about this geographical trivia.

After existing for about 5,000 years, the days of the glacier are numbered as research shows that it is melting and there is only a little left of it.

“The year when the glacier would be gone is between 2025 to 2027,” Mr Donaldi Permana, a climate research and development coordinator with the country’s meteorological, climatological and geophysical agency (BMKG) told CNA. He has studied the glacier extensively since 2009.

...

Other tropical glaciers in South America and Africa are also melting, Mr Permana noted.

However, as the elevation of Puncak Jaya is lower as compared to the other mountains with tropical glaciers, the one in Indonesia will disappear sooner.

THE MELTING IS ACCELERATING

Earlier studies have measured the area of the glacier, said Mr Permana.

Based on the soil maturity and vegetation distribution patterns around the glacier, it was concluded that the glacier area was about 19 sq km in 1850, he said.

Satellite imagery later showed that the glacier area was down to only 2 sq km in 2002.

By 2018, the size was only 0.46 sq km. Last year, it was 0.27 sq km. This means that the melting has accelerated over time.

To learn more about the glacier, Mr Permana and his colleagues extracted ice cores from it in 2010 by drilling 32m down to the bedrock. The ice cores were then taken to be examined.

The team also installed polyvinyl chloride (PVC) pipes to measure how much of the glacier is melting by looking at its thickness.

In 2015, they found that the pipe was exposed by 5m. “This means 1m of depth was gone per year,” Mr Permana noted.

They also noted that in 2016 when El Nino caused drier and warmer weather over Indonesia, the melting accelerated.

“From 2015 to 2016, in just one year, we lost 5m of depth,” he added.

He said that from 2016 to 2021, a further 12.5m of depth has been lost.

“Based on those figures, we can conclude that there is an acceleration (of melting),” he said. This was expected because when the glacier melts, the area around it becomes bigger, absorbing more solar radiation, added Mr Permana. 


..

“Maybe this (Indonesian) glacier’s contribution is not so significant because the initial area is not so big compared to the ones in South America or Greenland … But the animals and trees around the Papua area could be impacted by the melting, although unfortunately there is no study on this yet.”

Mr Permana also revealed that there is an indigenous tribe living around the area who worships the glacier. However, there has so far been no known study about this group and how they may be affected if the glacier disappears.

...

https://www.channelnewsasia.com/asia/indonesia-only-tropical-glacier-puncak-jaya-melting-2631916
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