Posts Tagged ‘climate’
“It is by the deep, hidden currents that the oceans are made one”*…
A significant part of the earth’s climate infrastructure is under threat. New research suggests the Atlantic Meridional Overturning Circulation (or AMOC) could weaken by half this century with wide ranging consequences for weather, food, and sea levels across the world. Alison Smart and Charlotte Venner unpack the past and ponder the future of this critical ocean current…
London, England, and Quebec City, Canada sit at roughly the same latitude (51°N and 47°N, respectively) but have vastly different climates. Historically, Quebec City had 99 freezing days in an average year—weather you might expect from its relative proximity to the Arctic—but London only experienced three freezing days in an average year, despite being slightly further north. This difference is largely due to an ocean current called the Atlantic Meridional Overturning Circulation (AMOC), which distributes warmth from the Tropics via the Atlantic Ocean.
Now, impacts from climate change are weakening the AMOC, and it could collapse entirely in the near future. AMOC collapse would rapidly make regions of the Northern Hemisphere with historically mild weather colder and harsher, while triggering irreversible changes in the global climate.
The AMOC is both the product of a stable climate and a factor in maintaining weather patterns around the planet. To plan for future scenarios, we need to first understand how the AMOC works and what might happen if it collapses…
[Smart and Venner explain the AMOC and outline the ways in which it shapes the climate of regions around the world…]
… Even minor weakening of the AMOC can significantly impact local climates, as has happened several times in the past 12,000 years. A “Little Ice Age” occurred in Europe in the Middle Ages, likely connected to a disruption in the AMOC. Just a slight slowdown in the AMOC could make Europe colder overall, disrupt global precipitation patterns from South America to India, and worsen drought in Africa.
The more freshwater pours into the ocean, and the more ocean temperatures rise, the weaker the AMOC becomes—until, at some threshold, it could stop moving altogether.
It is possible that the AMOC will collapse entirely if warming continues. There is no agreed-upon global average temperature at which collapse becomes certain, but there are signals we can track and historical examples we can examine to predict the likelihood of collapse…
… The consequences of total AMOC collapse would be far-reaching, severe, and irreversible on timescales relevant to humans. AMOC collapse would cool parts of the Northern Hemisphere and warm parts of the Southern Hemisphere by multiple degrees Celsius and drastically alter weather around the world.
In Europe, winter temperatures would drop, cold snaps could increase, and winter storms would intensify. A 2025 research letter found that, even if global warming reached 2°C, AMOC collapse would make Europe colder than it is today, creating extreme winters in Northwestern Europe in which record cold might reach -20°C (-4°F) in London and -50°C (-58°F) in Scandinavia. Even milder cold days would increase, with approximately 150 to 180 frost days per year in Utrecht, Netherlands, compared to a historic average of about 53. Precipitation would likely shift and decrease, potentially drying out some parts of Europe and making others wetter.
Around the world, other climates would change, likely in less extreme ways.
- North America. The East Coast of North America would likely experience rapid sea level rise as the gravitational pull of the AMOC weakens, as well as cooler conditions, with some parts of Eastern Canada and the North Atlantic coast cooling by several degrees Celsius, erratic storms, weather variability, and more intense hurricanes.
- Tropics & South America. Without the AMOC, the ITCZ would shift south, potentially leading to drying in the Northern Tropics and parts of the Amazon and wetter conditions in the Southern Tropics.
- Africa. Because of the shift in the ITCZ, West Africa and the Sahel would be much drier, experiencing severe and frequent drought and reduced rainy seasons. The Sahel could possibly transition from a semi-arid climate to hot dry desert.
- Asia. Because of the shift in the ITCZ, weakened and more erratic monsoons in Asia would lead to increased drought and a higher risk of extreme precipitation events.
These changes may occur rapidly, create climate risks, and cause systemic disruption in affected regions. The collapse of the AMOC would also be a tipping point in the global climate, meaning that the changes would likely be difficult, if not impossible, to reverse on human timescales.
Once the AMOC passes a critical threshold of weakening, called a tipping point, it would continue to weaken until it collapses. AMOC collapse could also create systemic impacts that activate other tipping points as well as feedback loops that could generate further warming.
For example, if AMOC collapse contributed to changes like a permanent dieback of the Amazon Rainforest or increased ice loss, those changes would generate their own warming effect on Earth’s climate. A 2026 paper suggests that AMOC collapse would result in substantial carbon release from oceans and add around 0.2°C in additional atmospheric warming.
Reducing greenhouse gas emissions may slow warming enough to reduce weakening and delay collapse. If collapse begins, it is unlikely we could stop it. There is no feasible technological way to reengineer ocean currents…
A bracing, but important read: “A complete guide to the Atlantic Meridional Overturning Circulation (AMOC).”
See also: “What would happen if the Atlantic Meridional Overturning Circulation (AMOC) collapses? How likely is it?”
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As we put on our sailin’ shoes, we might send interconnected birthday greetings to Andrew Sharrett; he was born on this date in 1946. An archaeologist, his application of world-systems theory to questions of change on large, often global, scale made him one of the most influential archaeologists of the late 20th/early 21st centuries. Sharrett is best known for his theory of the secondary products revolution; but his work touched on a broad range of fundamental human developmental issues: global migration and colonization, the spread of agriculture, the development of metallurgy and urbanism, and the development of new forms of consumption, to name a few. All of those dynamics were, as Sharrett observed, shaped in significant ways by the climatic conditions in which they unfolded.
“What is really amazing, and frustrating, is mankind’s habit of refusing to see the obvious and inevitable until it is there, and then muttering about unforeseen catastrophes”*…
One of the effectively-secret ingredients in the world’s economic growth over the last couple of centuries has been insurance. The ability to insure against catastrophic loss has underwritten (pun intended) the trillions and trillions of dollars of loans that have funded the construction and acquisition that has enabled the growth of both commercial endeavor and the the accumulation of personal wealth (directly through home ownership and indirectly through equity ownership in those commercial endeavors or participation in pension schemes that own that equity).
But in a way that was enitrely predictable, climate change is rendering a growing portion of the world uninsurable. Gavin Evans ponders what that might mean…
The Florida peninsula looks like a sore thumb. It juts into the Gulf of Mexico and the Atlantic, where the water is getting warmer year on year, prompting fiercer hurricanes that can blow down houses like collapsing decks of cards. Climate scientists are convinced all hell will break loose sooner or later when a monster-sized, property-destroying storm makes a direct hit on Miami or Tampa-St Petersburg. Given three near-misses in the recent past, the experts view such a calamity as inevitable. It’s a huge risk for anyone living there – they stand to lose everything – but also for those bearing the financial side of this risk, the insurance companies. Some in the industry are seeing this as a portent for their future – an impending existential threat with profound implications for the economic system.
There are no easy solutions for people still paying off mortgages and those who want to buy property along the Florida coast, because the potential payout on the back of a mammoth storm is so high that the reinsurers (who insure the insurers against catastrophe) are refusing to underwrite their clients and, with no reinsurance, there’s no insurance; and with no insurance, no mortgages; and with no mortgages, no property market. Insurance protects investments against loss and is therefore a pillar of the economic system. If it goes, economies are destabilised.
Many panicked homeowners have rushed to make their houses less risky for insurance companies by reinforcing their roofs with hurricane clips, installing impact-resistant windows, doors and shutters, and strengthening their foundations. But it’s not just storms and higher, warmer seas that concern insurers. Rising temperatures mean that the frequency, range and ferocity of wildfires are also on the rise.
So far this year, 3,374 wildfires have burned an area of Florida totalling 231,172 acres (at the time of writing), and it is even worse in California where 7,855 blazes have killed at least 31 people, destroyed more than 17,000 houses and devoured 525,208 acres of land, at an estimated cost of more than $250 billion. Here, too, homeowners rushed to make their properties more palatable to cold-footed insurers – clearing their surroundings of anything flammable, covering yards with gravel, sheathing houses with fire-resistant stucco, and replacing wooden roofs with steel.
But, even for the most diligent, insurance companies have turned tail, dumping existing clients and abandoning fire-prone and storm-prone areas altogether. On the Californian fire front, 2024 was a turning point as several insurers ceased issuing new policies because of fire-associated risks, including the United States’ biggest property insurer, State Farm, which cancelled policies in parts of Los Angeles. It is all too easy to view this cynically, but it’s happening because property insurers have been reporting year-on-year losses from climate change-related payouts.
Insurance companies survive by making more money from covering risk than they lose from these risks, which is why they prefer clients less likely to claim (insofar as they can predict the risk involved) and require them to pay substantial excess to discourage claims. When payouts rise above the premium intake, insurance companies either hike up these premiums or withdraw. But when that risk is considered catastrophic, potentially affecting many thousands of clients, as with Floridian storms and Californian fires, it is the reinsurers who are the first to retreat because they will ultimately bear most of the cost.
Reinsurers aggregate payout patterns to establish the likelihood of having to make huge payouts from future natural catastrophes. They do this by gathering exposure data from existing insurers in a geographical area, and by examining catastrophe models (computer simulations that estimate potential losses from natural perils). When they put all this together with detailed analysis of conditions within the area, they come up with a figure for their total potential loss if a catastrophic event strikes.
This is why reinsurers focus so intensely on climate change. Take a glance at the websites of big ones like Swiss Re and Munich Re and you get a sense of how central this is to their calculations – a concern that has spread to property insurers who are starting to hire climate consultants. Even more than market volatility, climate is their biggest headache. ‘You won’t meet a single insurance or reinsurance CEO who doesn’t believe in climate change,’ the insurance investor and former Lombard Insurance CEO James Orford told me. ‘They see it in the numbers – a combination of more extreme, less predictable events, combined with big losses of sums insured. All the modelling suggests these are uninsurable risks.’…
[Evans recaps the history of insurance, starting in Genoa, in the mid-14th century, with the insuring of maritime expeditions; examines the current state of play; examines the efforts (and gauges the weaknesses) of state’s efforts to step up with coverage when insurers step away; then considers another role for states…]
If states do withdraw from insurance and reinsurance, some of the most lucrative areas of the US, Canada, Europe, Asia, Africa and Australia will be devastated: no mortgages and no banks, leading to more ghost towns and villages. ‘It ends with depopulation and abandonment,’ said Agarwala. ‘Climate change reduces the operating space for humanity.’ In the UK, rising sea levels and coastal erosion could literally reduce operating space, putting 200,000 British homes at risk by 2050. There’s no coastal-erosion insurance, which puts more burden on the state, mainly to pay for new defences, but also to help people move.
Governments can take action in other ways, by investing greater sums in risk-prevention and management. There are signs of this happening such as the ‘fire-hardening’ and storm-prevention efforts in Florida, and improved flood defences in the UK; meanwhile, the EU’s Recovery and Resilience Facility is being used in several countries to build and renovate operations centres to cope with wildfires, and to buy firefighting helicopters.
In future, it is likely that voters will demand that their state and national governments do far more, regardless of the cost. They will want tougher building codes, including limitations on building in risky areas; expensive fire-prevention and fire-fighting schemes; better flood and storm defences; improved early catastrophe management, involving relocating people from risky areas and, when disaster strikes, rapid life-saving interventions such as large-scale emergency evacuations. If the insurance industry is forced to retreat by the climate crisis, all of this infrastructural investment will require vast chunks of taxpayers’ money. It is hard to avoid the feeling that this is part of our destiny, and that the sore thumb of the Florida peninsula is pointing us to the future…
Whole regions of the world are now uninsurable, bringing radical uncertainty to the economy: “The insurance catastrophe,” from @aeon.co.
See also: “An Uninsurable Country” (a report form NRDC), “The Insurance Crisis Is So Desperate People Are Turning Socialist” (a gift article from Bloomberg), and “The Uninsurable Future: The Climate Threat to Property Insurance, and How to Stop It” (from Yale Law Review)
* Isaac Asimov
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As we cover up, we might send highly-charged birthday greetings to a man who made foundational contributions both to the detection of climatic conditions and to a technology that may help allieviate climate change: John Frederic Daniell was born on this date in 1790. Named the first professor of chemistry at the newly founded King’s College London in 1831, he was an avid meteorologist. He invented the dew-point hygrometer known by his name and a register pyrometer; in 1830 he erected a water-barometer in the hall of the Royal Society.
But Daniell is better remembered as a chemist (and physicist), especially for his invention of the Daniell cell, an element of an electric battery much better than voltaic cells, the standard before him. Indeed, the Daniell cell is the historical basis for the contemporary definition of the volt (the unit of electromotive force in the International System of Units). All advances in battery technology since then were “from” the base that Daniell laid.
“There are things done today in electrical science which would have been deemed unholy by the very men who discovered electricity, who would themselves not so long before have been burned as wizards”*…
Climate change continues. There is broad evidence (and consensus) that our environment, thus our ways of life, our livelihoods— indeed, our lives— are threatened. On the heels of a call from Trump to world leaders to abandon the climate fight, followed by a disappointing COP30 conference, it’s easy to be discouraged. But that, of course, is no answer.
Rather, we have to find ways to mitigate the damage that we’ve already locked in, even as we acclerate a transition to clean energy… which begins by (re-)framing and (re-)focusing the challenge. Ember, a clean energy think tank, suggests a candidate that, while it speaks to the moral obligations addressed by one of the models it means to augment/replace, has a more positive orientation…
Humanity is graduating from burning fossil commodities to harnessing manufactured technologies—from hunting scarce fossils to farming the inexhaustible sun, from consuming Earth’s resources to
merely borrowing them.This isn’t a marginal climate substitution. It’s an energy revolution.
The magnetic centre is the electron: we are revolutionising how we generate, use, and connect
electrons. Solar and wind are conquering electricity supply. EVs, heat pumps, and AI are electrifying major new uses. Batteries and digitalisation are connecting supply and demand.Three reinforcing shifts. One energy revolution. The electrotech revolution.
At its core, this revolution is driven by physics, economics, and geopolitics. After all, the arc of energy
history bends towards solutions that are leaner, cheaper and more secure.Short-terms setbacks matter, but fundamentals matter more. And the fundamentals are stacked in electrotech’s favour.
Physics. Electrotech makes a mockery of setting fossils on fire and losing two-thirds of the energy to heat. Electrotech is three times as efficient.
Economics. Technologies get cheaper with scale. Commodities get more expensive the deeper you dig.
Geopolitics. Three quarters of the world is dependent on fossil imports. 92% of countries have renewables potential over 10x their current demand.
Electrotech has grown exponentially for decades. The difference today is that it’s too cheap to contain and too big to ignore. If current exponentials hold for five more years, global fossil demand will fall off its plateau.
Welcome to the Age of Electrotech…
A long and meaty presentation: “The Electrotech Revolution- the shape of things to come,” from @ember-energy.org.
One notes that the electrification that Ember pushes has other advocates, many of whom have been vocal for years; c.f., e.g., Saul Griffin. Still, another voice in the chorus is welcome.
* Bram Stoker
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As we plug in, we might send charged birthday greetings to Franz Aepinus; he was born on this date in 1724. A mathematician, scientist, and natural philosopher, he is best known for his research, both theoretical and experimental, into electricity and magnetism. Aepinus’ Tentamen theoriae electricitatis et magnetismi (1759; “An Attempt at a Theory of Electricity and Magnetism”) was the first work to apply mathematics to the theory of electricity and magnetism. And his experiments led to the design of the parallel-plate capacitor, a device used to store energy in an electric field.
“We are the first generation to feel the effect of climate change and the last generation who can do something about it”*…
One of the issues that vexes coordinated response is a paradox that lies at the heart of the phenomenon: Earth’s climate is chaotic and volatile. Climate change is simple and predictable. How can both be true? Joseph Howlett explains…
The Earth’s atmosphere is nothing but freely roaming molecules. Left alone, they would drift and collide, and eventually even out into a mixture that’s dynamic, yet stable and broadly unchanging.
The sun’s rays complicate things. Energy enters the Earth system in daily cycles, the bulk of it going to whichever half of the planet is tilted toward the sun (and experiencing summer). The molecules in that half acquire more energy than others, which sets the global atmosphere steadily swirling. Depending on the season and location, molecules in our atmosphere might traverse warm land, then cold seas. They might encounter a mountain range that forces them to high altitudes, where the air pressure is low and water condenses. Then they might become part of large-scale phenomena, such as currents, atmospheric rivers, turbulent jet streams and continental fronts.
These phenomena are erratic. They interact at every scale and manifest as weather, from clear sunny days to blustery blizzards and the anomalous events — from hurricanes and polar vortices to hailstorms and tornadoes — that are happening with increasing intensity. Any thought of stability is illusory; no patch of molecules dances in isolation.
The result, from seemingly simple inputs of molecules and energy, is emergent, incalculable chaos. Some individual molecule in the room you are sitting in is careening about blindly and colliding with its immediate neighbors. Zoom out — block to city, field to landscape, region to continent — and patterns appear and intermix. Complexity abounds and compounds. Nothing in the atmosphere is untethered from the rest of the global picture.
We live with this unpredictable mess of an atmosphere every day. We tote around unopened umbrellas, or refresh weather apps and watch our weekend plans dissolve. Anticipating conditions any further out than a week or two is a fool’s errand. The Earth is a complex dynamical system — an interwoven mass of moving parts, each of which requires a different branch of science to understand. Even with advanced knowledge, sophisticated algorithms and modern instruments, it defies and eludes us.
Yet this engine of chaos is now under our influence. It is incontrovertible fact that we are changing the Earth’s temperature by adding more carbon dioxide to the atmosphere. We know exactly how we are changing it — that when we double the proportion of carbon dioxide in the thin layer that rests over the surface of the Earth, the planet will become 2 to 4 degrees Celsius warmer, overall, than it is today. This conclusion has remained essentially unchanged since 1896, when the Swedish scientist Svante Arrhenius arrived at an estimate of 2 to 5 degrees. (Using an extraordinarily simplified picture of Earth, he made a number of mistakes that, in the end, balanced out.) Some details may remain uncertain, some chaos untamable, but the basic conclusion is a matter of unwavering scientific agreement — 97% is a rare degree of consensus on almost any subject. We are nearly as sure of this as we are of the causes of infectious disease, or how stars form, or the fact that life evolves through natural selection.
oth things are true: The climate system is vastly complex, and we’re certain about what we are doing to it. How can we be so confident in a hundred-year projection when we can’t predict the weather with any reliability more than a week out?
“How can it be that both are true?” said Nadir Jeevanjee, an atmospheric physicist at NOAA’s Geophysical Fluid Dynamics Laboratory, a leading institution for cutting-edge simulations of the atmosphere. “It’s a huge tension that’s lurking behind the whole conversation.”
It turns out that complexity can be a veil concealing more basic truths. An enormously complicated system can yield simple answers. You just have to ask a simple enough question…
Read on for Howlett’s fascinating– and important– explanation: “The Climate Change Paradox,” from @quantamagazine.bsky.social.
And for a reminder that this matters (as though we need one…): “Human-Caused Warming Tripled the Death Toll of European Heat Waves This Summer, New Report Shows,” from @insideclimatenews.org.
* Barack Obama
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As face reality, we might recall that on this date in 1988, the #1 song in the U.S. was Bobby McFerrin‘s “Don’t Worry, Be Happy,” the first a cappella song to reach the top of the Billboard Hot 100 chart, a position it held for two weeks.
(Produced by Colossal Pictures, Directed by Drew Takahashi)
“Sooner or later everyone sits down to a banquet of consequences”*…
A report issued by International Chamber of Commerce late last year found that extreme weather cost $2tn globally over last decade; the U.S. suffered the greatest losses. As Damian Carrington reports, a leading insurance executive is warning that urgent action is needed to save the conditions under which markets – and civilization itself – can operate…
The climate crisis is on track to destroy capitalism, a top insurer has warned, with the vast cost of extreme weather impacts leaving the financial sector unable to operate.
The world is fast approaching temperature levels where insurers will no longer be able to offer cover for many climate risks, said Günther Thallinger, on the board of Allianz SE, one of the world’s biggest insurance companies. He said that without insurance, which is already being pulled in some places, many other financial services become unviable, from mortgages to investments.
Global carbon emissions are still rising and current policies will result in a rise in global temperature between 2.2C and 3.4C above pre-industrial levels. The damage at 3C will be so great that governments will be unable to provide financial bailouts and it will be impossible to adapt to many climate impacts, said Thallinger, who is also the chair of the German company’s investment board and was previously CEO of Allianz Investment Management.
The core business of the insurance industry is risk management and it has long taken the dangers of global heating very seriously. In recent reports, Aviva said extreme weather damages for the decade to 2023 hit $2tn, while GallagherRE said the figure was $400bn in 2024. Zurich said it was “essential” to hit net zero by 2050.
Thallinger said: “The good news is we already have the technologies to switch from fossil combustion to zero-emission energy. The only thing missing is speed and scale. This is about saving the conditions under which markets, finance, and civilisation itself can continue to operate.”
Nick Robins, the chair of the Just Transition Finance Lab at the London School of Economics, said: “This devastating analysis from a global insurance leader sets out not just the financial but also the civilisational threat posed by climate change. It needs to be the basis for renewed action, particularly in the countries of the global south.”
“The insurance sector is a canary in the coalmine when it comes to climate impacts,” said Janos Pasztor, former UN assistant secretary-general for climate change.
The argument set out by Thallinger in a LinkedIn post begins with the increasingly severe damage being caused by the climate crisis: “Heat and water destroy capital. Flooded homes lose value. Overheated cities become uninhabitable. Entire asset classes are degrading in real time.”
“We are fast approaching temperature levels – 1.5C, 2C, 3C – where insurers will no longer be able to offer coverage for many of these risks,” he said. “The math breaks down: the premiums required exceed what people or companies can pay. This is already happening. Entire regions are becoming uninsurable.” He cited companies ending home insurance in California due to wildfires.
Thallinger said it was a systemic risk “threatening the very foundation of the financial sector”, because a lack of insurance means other financial services become unavailable: “This is a climate-induced credit crunch.”
“This applies not only to housing, but to infrastructure, transportation, agriculture, and industry,” he said. “The economic value of entire regions – coastal, arid, wildfire-prone – will begin to vanish from financial ledgers. Markets will reprice, rapidly and brutally. This is what a climate-driven market failure looks like.”
No governments will realistically be able to cover the damage when multiple high-cost events happen in rapid succession, as climate models predict, Thallinger said. Australia’s disaster recovery spending has already increased sevenfold between 2017 and 2023, he noted.
The idea that billions of people can just adapt to worsening climate impacts is a “false comfort”, he said: “There is no way to ‘adapt’ to temperatures beyond human tolerance … Whole cities built on flood plains cannot simply pick up and move uphill.”
At 3C of global heating, climate damage cannot be insured against, covered by governments, or adapted to, Thallinger said: “That means no more mortgages, no new real estate development, no long-term investment, no financial stability. The financial sector as we know it ceases to function. And with it, capitalism as we know it ceases to be viable.”
The only solution was to cut fossil fuel burning, or capture the emissions, he said, with everything else being a delay or distraction. He said capitalism must solve the crisis, starting with putting its sustainability goals on the same level as financial goals.
Many financial institutions have moved away from climate action after the election of the US president, Donald Trump, who has called such action a “green scam”. Thallinger said in February: “The cost of inaction is higher than the cost of transformation and adaptation. If we succeed in our transition, we will enjoy a more efficient, competitive economy [and] a higher quality of life.”…
It’s time, if not past time, to act: “Climate crisis on track to destroy capitalism, warns top insurer,” from @dpcarrington.bsky.social in @theguardian.com.
Further to the point: “Get ready for several years of killer heat, top weather forecasters warn.”
See also: “Q&A: Kiley Bense on Climate Journalism in a New Information Environment.”
(Image above: source)
* Robert Louis Stevenson
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As we contemplate craziness, we might recall that it was on this date in 2011 that the Wallow Fire started. A wildfire that started in the White Mountains near Alpine, Arizona, it was named for the Bear Wallow Wilderness area where the fire originated.
The fire eventually spread across the stateline into western New Mexico. By the time the fire was contained on July 8, it had consumed 538,049 acres of land, 522,642 acres in Arizona and 15,407 acres in New Mexico. It was the largest wildfire in Arizona history and did an estimated estimated cost was $109 million in damages. Smoke from the Wallow Fires and others in Arizona and New Mexico extended through Texas and Oklahoma up into the Great Lakes region, affecting air quality for large areas east of the Rocky Mountains.
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