Australian Targets

▼

Saturday, December 2, 2023

Cryosphere in peril: Calls by Scientists, President of Chile, Prime Minister of Iceland, UN Chief to phase out Fossil Fuels at COP28

Before attending COP28 in Dubai, UN Secretary General Antonio Guterres did a flying vist to Antarctica with Gabriel Boric, President of Chile, to see and talk with polar scientists on the changes to the Cryosphere and Antarctica in particular.

 "What happens in Antarctica doesn’t stay in Antarctica. " Guterres said.

"Without changing course, we’re heading towards a calamitous three-degree Celsius temperature rise by the end of the century. That means losing the West Antarctica Ice Sheet almost entirely. This alone could ultimately push up sea levels by around five meters." said the UN Chief.

The International Cryosphere Climate Initiative published its latest State of the Cryosphere report 2023 on 16 November 2023, outlining in 6 detailed chapters covering the changes and impacts of Ice Sheets, Mountain Glaciers and Snow, Sea Ice, Permafrost and Polar Oceans. The report included a forward by the President of Chile and Prime Minister of Iceland calling for a phaseout of fossil fuels to limit damages to the cryosphere, and consideration of the issue in the Global Stocktake at COP28. 

The Cryosphere and COP28

Hobart's Lord Mayor has already visited the Cryosphere Pavillion at COP28. I wonder if Climate Minister Chris Bowen will pay a visit? It might inspire him for Australia to support Fossil Fuel phaseout this decade as part of the Global Stocktake and in the cover decision.



19 November: Sea Level rise projections grossly under-estimated says major peer reviewed Cryosphere science report, Two Degrees is Too High, by International Cryosphere Climate Initiative. The report estimates that 12 to 20 metres is likely over hundreds of years from a 2C rise in temperature with dissolution of most of Greenland, West Antarctica and parts of East Antarctica. (Global News CA| International Cryosphere Climate Initiative)

12 November - At Paris summit France's President Macron pledges €1bn to fund research into melting ice caps (Guardian) Macron: “We are not talking about a threat for tomorrow, but one that is already present and accelerating. We are talking about a transformation of the cryosphere [the Earth’s ice] that already threatens millions and will threaten billions of the planet’s inhabitants with multiple direct and indirect consequences.”

Pam Pearson, founder and director of the International Cryosphere Climate Initiative, a thinktank, warned of the urgency: “Politicians think that the ice is far away. The ice does not care. It will continue melting until carbon dioxide levels stop rising and come down. But they are still rising just as fast as they were 20 years ago. Scientists are screaming that this is insanity.”

Macron, seated opposite her, looked grave, as Pearson, who spent 20 years as a US diplomat working on conflict and geopolitical concerns, continued: “I know that climate change is seen as a soft issue [compared with wars and national security]… but we can’t negotiate with the melting point of ice.”

State of the Cryosphere Report says 2°C too high,1.5°C target needed

A preface to the report by Gabrtiel Boric, President of Chile, and Katrín Jakobsdóttir Prime Minister of  Iceland as Co-Chairs and Founding Members, Ambition on Melting Ice (AMI), argues the urgency to phase out fossil fuels and the consideration in the Global Stocktake dialogs at COP28 in Dubai, of the perils facing the Cryosphere and how that will impact humans and society.

At COP28, we need a frank Global Stocktake, and fresh urgency especially due to what we have learned about Cryosphere feedbacks, worsening for each additional tenth of a degree in temperature rise. We need tangible results, and clear message about the urgency to phase out fossil fuels and for more robust financial mechanisms to finance climate action.

We have time, but not much time. Past alerts are today’s shocking facts. Present warnings will be tomorrow’s cascading disasters, both within and from the global Cryosphere, if we do not accelerate climate action and implement systemic change.

Change is hard, but change we must. Because of the Cryosphere, climate inaction is unacceptable.

The scientists who contributed to this report write in the foreward that "even the 2°C target is too high. The Paris Agreement’s “well below 2°C” can mean just one thing: 1.5°C alone" . They argue that this be enshrined in the COP cover decision, and also that the Global Stocktake set "clear guidelines to make 1.5°C a reality; a path to phase out fossil fuels; and financial mechanisms to support climate action, as well as the adaptation, and loss and damage – most of it ultimately tied to irreversible Cryosphere loss -- now inevitable even below 1.5°C; but far worse above that."

Enough. It is time to carve a line in the snow: because of what we have learned about the Cryosphere since the Paris Agreement was signed in 2015, 1.5°C is not merely preferable to 2°C. It is the only option.

At COP28, we call on global leaders to enshrine this reality in the Cover Decision: because of the Cryosphere response, even 2°C is too high. The Paris Agreement’s “well below 2°C” can mean just one thing: 1.5°C alone.

We therefore need a Stocktake with clear guidelines to make 1.5°C a reality; a path to phase out fossil fuels and financial mechanisms to support climate action, as well as the adaptation, and loss and damage – most of it ultimately tied to irreversible Cryosphere loss -- now inevitable even below 1.5°C; but far worse above that.

For regions like the Hindu Kush Himalaya, frankly even1.5°C is too high.

The Executive Summary explains in detailed point form the arguments in the 6 specific chapters of this report on the perils facing the Cryosphere with Global Warming.

Ice Sheets

  • 2°C will result in extensive, potentially rapid, irreversible sea-level rise from Earth’s ice sheets; 3°C will further speed up this loss to within the next few centuries.
  • A compelling number of new studies, taking into account ice dynamics, paleo-climate records from Earth’s past, and recent observations of ice sheet behavior, all point to a threshold for both Greenland and parts of Antarctica well below 2°C, committing the planet to between 12–20 meters sea-level rise if 2°C becomes the new constant Earth temperature.
  • The most recent projections show a slow, but continuing pattern of sea-level rise (SLR) for many centuries even with “low emissions” (SSP1-2.6). This is an emissions pathway that peaks at 1.8°C and returns close to 1.6°C by 2100; yet the models show SLR continuing at this slow pace, indicating some level of ice loss has been irreversibly triggered even by this brief period of overshoot.
  • Many ice sheet scientists now believe that by 2°C, nearly all of Greenland, much of West Antarctica, and even vulnerable portions of East Antarctica will be triggered to very long-term, inexorable sea-level rise, even if air temperatures later decrease. This is due to a warmer ocean that will hold heat longer than the atmosphere, plus a number of self-reinforcing feedback mechanisms, so that it takes much longer for ice sheets to regrow (tens of thousands of years) than lose their ice.
  • If global leaders cause temperatures to reach this point through continued fossil emissions, they are committing the planet to extensive coastal loss and damage well beyond limits of feasible adaptation.
  • Latest projections show that only “very low” emissions and the 1.5°C Paris limit reliably maintains both ice sheets, preventing massive long-term sea-level rise.

Mountain Glaciers and Snow

  • Measurements now confirm that essentially all mountain glaciers worldwide are losing ice: some, such as those in the Alps, at distressingly rapid rates over the past two summers alone.
  • 2°C will result in extensive, long-term, essentially irreversible ice loss from many of the world’s glaciers in many major river basins, with some disappearing entirely. Snow cover also will greatly diminish. A rise of 3°C will spread and greatly speed up this loss.
  • If 2°C warming is reached, projections show that nearly all tropical glaciers (north Andes, Africa) and most mid-latitude glaciers outside the Himalayas and polar regions will disappear, some as early as 2050. Others are large enough to delay complete loss until the next century, but have already passed a point of no return. Even the Himalayas are projected to lose around 50% of today’s ice at 2°C.
  • As glaciers melt, risks of catastrophic events – landslides, sudden ice shears, and in some cases glacial lake outburst floods – will rise, affecting entire communities.
  • Winter snowpack at 2°C generally will decrease, but also become more volatile; with some years of hardly any snow, and others with record-breaking amounts that threaten infrastructure and lives.
  • Losses in both snowpack and glacier ice will have dramatic impacts on downstream dry season water availability for agriculture, power generation, and drinking. Impacts may be extreme in especially vulnerable river basins, such as the Tarim in northwest China and the Indus.
  • Continued warming, even through the brief 1.6°C peak of very low emissions (SSP1-1.9) still means that today’s very fast ice loss in glaciers globally will continue through at least the 2050s. With very low emissions, this loss will begin to slow in at least some regions around 2060, and stabilize towards the end of this century.
  • With very low emissions, some glaciers may even show slow re-growth in the 2100s, though this would occur extremely slowly (many decades to centuries). Such visible snow and ice preservation, and its benefits for freshwater resources, may be one of the earliest and visible signs to humanity that steps towards low emissions have meaningful results.

Sea Ice

  • Perhaps more so than for any other part of the cryosphere, 2°C is far too high to prevent extensive seaice loss at both poles, with severe feedbacks to global weather and climate.
  • By 2°C, the Arctic Ocean will be sea ice-free in summer not occasionally, but almost every year; and for periods of up to four months (July–October). The most recent projections show frequent ice-free conditions by 2050 even with “low emissions” (SSP1-2.6), a carbon pathway that peaks at 1.8°C.
  • Open water in the Arctic for several months will absorb more heat from polar 24-hour sunlight conditions. A warmer Arctic will increase coastal permafrost thaw – adding more carbon to the atmosphere – and speed Greenland Ice Sheet melt and resulting sea-level rise.
  • It also means that any Arctic sea ice recovery may take many decades, even with a subsequent return to lower atmospheric temperatures, because the water will hold that heat far longer.
  • In the Antarctic, complete loss of sea ice every summer seems plausible at 2°C if current trends continue, and would almost certainly speed up loss from the Antarctic ice sheet and resulting sea-level rise. Record-low conditions in 2023 around much of Antarctica indicate that its threshold for complete summer sea ice loss might be even lower than for the Arctic.
  • Studies consistently indicate that Arctic sea ice will still melt almost completely some summers even at 1.5°C, but not each year and only for a brief period (days to a few weeks) when it does. Only “very low” emissions (SSP1-1.9, which peaks at 1.6°C) can maintain summer Arctic sea ice, and lead to some recovery by 2100, when temperatures begin to decline below 1.4°C.
  • Negative impacts on sea ice-dependent Indigenous communities and ecosystems will still be significant, however, since at least one ice-free summer is now inevitable before 2050 even with “very low” emissions, according to the IPCC.

Permafrost

  • 2°C – and even 1.5°C – is too high to prevent extensive permafrost thaw and resulting CO2 and methane emissions that will cause temperatures to continue to rise, even once human emissions reach zero, unless offset by extensive negative emissions/carbon drawdown; but 1.5°C will decrease the size of such emissions significantly.
  • 2°C means 4–8°C in the Arctic where most permafrost is located, with parts of the Arctic warming 2–4 times faster than the rest of the planet. In addition, up to half of recent permafrost thaw has occurred during extreme heat events of up to 12°C above average, as a result of “abrupt thaw” processes where coastlines or hillsides collapse, or lakes form; exposing much deeper and greater amounts of permafrost to thaw.
  • Once thawed, permafrost begins emitting CO2 or methane, even if temperatures later drop below freezing. These emissions are irreversibly set in motion and will not slow for 1–2 centuries, meaning that future generations must offset them (draw down carbon) at scales the size of a major emitter.
  • At 2°C, annual total permafrost emissions (both CO2 and methane) would probably total the size of the entire European Union’s emissions from 2019 (≈200Gt total by 2100 and about twice that by 2300). Permafrost thaw at 2°C might also be accelerated further by loss of Arctic sea ice in summer for several months, as the open water absorbs more heat; and by increased wildfires in Siberia and North America.
  • Even at 1.5°C, studies indicate significant permafrost thaw and related emissions, but these will be less in scale since temperatures will “only” average 3–4°C higher than today in the Arctic. “Very low” emissions (SSP1-1.9 also result in temperatures declining to below 1.4°C by the end of this century, preventing most additional new thaw.
  • Annual permafrost emissions will still need to be offset by future generations, but should be 30–50% less, more on the scale of India in 2019 (150Gt by 2100).

Polar Oceans

  • 2°C will result in year-round, essentially permanent corrosive ocean acidification conditions in extensive regions of Earth’s polar and some near-polar seas; with widespread negative impacts on key fisheries and species.
  • This is because all 2°C emissions pathways lead to CO2 levels in the atmosphere well above 450 ppm, the critical level for polar oceans identified decades ago by marine scientists. The Arctic and Southern Oceans already are bearing the brunt of acidification impacts because they absorb CO2 faster. Some near-polar oceans, especially the Barents, North and Baltic seas, also would have acidification levels rivaling that of the poles.
  • Shell-building animals, and commercial fisheries that rely on them in the food chain – valuable species such as krill, cod, salmon, lobsters, king crab, to name just a few – may not survive in the wild or when cultivated in these corrosive waters. With warmer ocean temperatures and lack of protective sea ice for several months each summer, marine heat waves and extreme acidification events will cause additional losses.
  • These “overshoot” corrosive conditions, set by peak atmospheric CO2 levels, are essentially irreversible, lasting 30–70,000 years.
  • The “very low” emissions pathways resulting in temperatures close to the 1.5°C Paris limit would on the other hand reliably maintain atmospheric CO2 well below 450 ppm; the most ambitious (SSP1-1.9) sees CO2 levels peak at 430 ppm. This will limit corrosive stressing conditions to mostly seasonal damage in smaller sections of the Arctic and Southern Oceans, spreading marginally from what is already seen as shell damage today.
  • This 430 ppm threshold is very close however: the May 2023 monthly average CO2 level at Mauna Loa Observatory was 424 ppm. Destructive compound events combining marine heatwaves and extreme acidification have already caused population crashes even at today’s 1.2°C.

Antarctic Sea Ice Extent Anomaly to mid July 2023. Source: Prof Eliot Jacobson

Early warning signs from East Antarctica

Webinar from the Cryosphere Pavillion at COP28 in Dubai on 2 December 2023

Early Warning Signs of Sea Level Rise from the World’s Largest Ice Sheet in East Antarctica.

"The East Antarctic Ice Sheet (EAIS) is the world’s largest ice mass, storing over 52 meters of sea level equivalent (SLE). It is often viewed as less vulnerable to global warming than the West Antarctic (5.3 m SLE) and Greenland ice sheets (7.4 m SLE), but recent work has detected worrying signs from East Antarctica and its surrounding oceans, suggesting that we are close to a threshold that might see several meters added to sea level over the next few centuries. This event will summarize the latest science on the EAIS, much of it since IPCC AR6, that points to the clear danger of exceeding 1.5 °C.

Contacts: Durham University, University of Tasmania (UTAS), Monash University"

Climate scientist Ella Gilbert: We can’t save the West Antarctic. So what now?

Polar climate scientist Ella Gilbert discusses the latest research on West Antarctic Ice sheet collapse in Nature Climate Change Naughten et al. (Oct 2023), Unavoidable future increase in West Antarctic ice-shelf melting over the twenty-first century


Transcript of Speech by Antonio Guterres on Antarctica

Brief speech after returning from Antarctica where the UN Secretary General talked to Antarctic scientists.

Antarctica has been called the sleeping giant.

And it is being awoken by climate chaos.

Antarctic sea ice is at an all-time low.

New figures show that this September, it was 1.5 million square kilometres smaller than the average for the time of year – an area roughly the size of Portugal, Spain, France and Germany combined.  

The Greenland ice sheet is also melting fast – losing over 250 gigatons of ice every year. 

All of this spells catastrophe around the world.

What happens in Antarctica doesn’t stay in Antarctica. 

And what happens thousands of miles away has a direct impact right here.

We live in an interconnected world. 

Fossil fuel pollution is heating our planet, unleashing climate anarchy in Antarctica. 

The Southern Ocean has taken the majority of the heat from global warming.

That means ice melting into the ocean at record rates.

Melting ice means sea-levels rising at record rates.

That directly endangers the lives and livelihoods of people in coastal communities across the globe.

It means homes are no longer insurable.

And it threatens the very existence of some small island states.

Without changing course, we’re heading towards a calamitous three-degree Celsius temperature rise by the end of the century.

That means losing the West Antarctica Ice Sheet almost entirely.

This alone could ultimately push up sea levels by around five meters.

We are trapped in a deadly cycle.

Ice reflects the sun’s rays. As it vanishes, more heat is absorbed into the Earth’s atmosphere.

That means more heating, which means more storms, floods, fires and droughts across the globe. And more melting. Which means more heating.

This destruction is a direct result of our fossil fuel addiction.

So as leaders gather for COP28, my message is clear:

Break this cycle.

And act now: to limit global temperature rise to 1.5 degrees Celsius, protect people from climate chaos, and end the fossil fuel age.

We must not let all hopes for a sustainable planet melt away.



References

UN Secretary General, 25 November 2023, Secretary-General's video message from Antarctica https://www.un.org/sg/en/content/sg/statement/2023-11-25/secretary-generals-video-message-antarctica 

ICCI, 2023. State of the Cryosphere 2023 – Two Degrees is Too High. International Cryosphere Climate Initiative (ICCI), Stockholm, Sweden. 62 pp. https://iccinet.org/statecryo23/

Nature Climate, Naughten et al. (23 Oct 2023), Unavoidable future increase in West Antarctic ice-shelf melting over the twenty-first century https://www.nature.com/articles/s41558-023-01818-x


at

No comments:

Post a Comment