Mostrar mensagens com a etiqueta William Ripple. Mostrar todas as mensagens
Mostrar mensagens com a etiqueta William Ripple. Mostrar todas as mensagens

quinta-feira, 23 de abril de 2026

A catastrophic climate event is upon us. Here is why you’ve heard so little about it


The poor and middle pay taxes, the rich pay accountants, the very rich pay lawyers – and the ultra-rich pay politicians. It’s not an original remark, but it bears repeating until everyone has heard it. The more money billionaires accumulate, the greater their control of the political system – which means they pay less tax, which means they accumulate more, which means their control intensifies.

They reshape the world to suit their demands. One of the symptoms of the pathology known as “billionaire brain” is an inability to see beyond their own short-term gain. They would sack the planet for a few more stones on the pointless mountain of wealth. And we can see it happening. Last week delivered the biggest news of the year so far, perhaps the biggest news of the century. But partly because billionaires own most of the media, most people never heard it. We might find ourselves committed to a civilisation-ending event before we even learn that such a thing is possible.

The news is that the state of a crucial oceanic circulation system has been reassessed by scientists. Some now believe that, as a result of climate breakdown changing the temperature and salinity of seawater, it is more likely than not to collapse. This system – known as the Atlantic meridional overturning circulation (Amoc) – delivers heat from the tropics to the North Atlantic. Recent research suggests that if it shuts down, it could cause both a massive drop in average winter temperatures in northern Europe and drastic changes in the Amazon’s water cycles. This could help tip the rainforest into cascading collapse and trigger further disaster.

Amoc’s shutdown is likely also to cause an acceleration of sea level rise on the east coast of the US, threatening cities. It could also raise Antarctic temperatures by roughly 6C and release a vast pulse of carbon currently stored in the Southern Ocean, accelerating climate catastrophe.

Even when the countervailing effects of generalised global heating are taken into account, a further paper proposes, the net impact in northern Europe would be periods of extreme cold – including events in which temperatures in London fall to -19C, in Edinburgh to -30C and in Oslo to -48C. Sea ice in February would extend as far as Lincolnshire. Our climate would change drastically, with the likelihood of far greater extremes, such as massive winter storms. Rain-fed arable agriculture would become impossible almost everywhere in the UK.

This shift, on any realistic human scale, would be irreversible. Its speed is likely to outrun our ability to adapt. Amoc shutdowns, driven by natural climate variability, have happened before. But not in the era of large-scale human civilisation.

The first paper proposing that Amoc might have an on-state and an off-state was published in 1961. Since then, many studies have confirmed the finding and explored potential triggers and likely implications. Until recently, Amoc collapse caused by human activity fell into the category of a “high impact, low probability” event, devastating if it happens, but unlikely to occur. Research over the past few years prompted a reassessment: it began to look more like a “high impact, high probability” event. Now, in response to last week’s paper, Prof Stefan Rahmstorf – perhaps the world’s leading authority on the subject – says the chances of a shutdown look like “more than 50%”. We could pass the tipping point, he says, “in the middle of this century”.

So why is this not all over the news? Why is it not the top priority for the governments that claim to protect us from harm? Well, in large part because oligarchic power has championed a model of climate impact that bears little relation to reality: that is, they have a hypothesis about how the world works that is completely detached from scientific findings. This model underpins official responses to the climate crisis.

It began with the work of the economist William Nordhaus, who sought to assess the economic effects of global heating. His modelling suggests that a “socially optimal” level of heating is between 3.5C and 4C. Most climate scientists see a temperature rise of this kind as catastrophic. Even 6C of heating, Nordhaus suggests, would cause a loss of just 8.5% of GDP. Climate science suggests it would look more like curtains for civilisation.

As the eminent economists Nicholas Stern, Joseph Stiglitz and Charlotte Taylor have argued, the mild effects Nordhaus forecasts are merely artefacts of the model he has used. For example, his modelling assumes that catastrophic risks do not exist and that climate impacts rise linearly with temperature. There is no climate model that proposes such a trend. Instead, climate science forecasts nonlinear impacts and greatly escalating risk. The likely impacts of high levels of heating include the inundation of major cities, the closure of the human climate niche (the conditions that sustain human life) across large parts of the globe, the collapse of the global food system and cascading regime shifts – that is, abrupt transitions in ecosystems – releasing natural carbon stores, potentially leading to a “hothouse Earth” in which very few survive. Never mind a few points off GDP: there would be no means of measurement and scarcely an economy to measure.

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quinta-feira, 16 de abril de 2026

Measuring Ecological Limits: The United States and the World


The science is clear: Our rate of economic activity is having disastrous impacts on the environment, starting with the climate so crucial to our survival. Economic activities require the use of natural resources and systematically entail pollution. Resources eventually get used up, as does the capacity of the planet to assimilate waste. We are reminded of Herman Daly’s long-running emphasis that the economy is a subsystem of the environment, not the other way around.

Expanding on this, steady-state economists and other post-growth advocates argue that economic growth cannot be decoupled from material throughput. This can be explained with the trophic theory of money, which follows from the trophic structure of the economy of nature. Agriculture and extraction comprise the trophic foundation of the economy, and all other sectors rely on that trophic base. Therefore, we cannot rely on “dematerialized” sectors to grow the economy while decreasing its disastrous impacts on the environment.

Therefore, consumption must be reduced, particularly in high-income countries that consume more natural resources and release more waste. But just how much do high-income countries need to reduce their economic activity to be sustainable? Two metrics help us understand sustainable limits by quantifying the relationship between the environment and the economy: ecological footprint and biocapacity.

The Conceptual Framing of Ecological Footprint and Biocapacity
The ecological footprint is a measure of the area needed to support the demands of economic activity. Biocapacity is a measure of the area available to supply natural resources and absorb waste at a sustainable rate. When the ecological footprint exceeds biocapacity, that indicates ecological overshoot. The Ecological Footprint Initiative has been measuring global ecological footprint and biocapacity since 1961. We have been in overshoot since 1971.

The ecological footprint and biocapacity are made up of comparable components, including cropland, grazing land, forest land, fishing grounds, and built-up land. In addition, ecological footprint includes a carbon component.

Scientists measure ecological footprint and biocapacity with a unit called the global hectare. They convert the productivity of different ecosystems to global hectares based on the world average productivity of a hectare. This enables comparisons between different land types, places, and years.
Ecological Footprint and Biocapacity of the United States

The United States has a high ecological footprint that is larger than its biocapacity. In 2022, there were roughly one billion hectares across the United States. When categorized into the biocapacity components and compared to global average productivity, this equates to 1.25 billion global hectares (gha) of biocapacity.

In other words, U.S. land, most notably cropland and forest land, was more productive than the global average. The average biocapacity of one hectare of U.S. cropland was 3.7 gha. One hectare of forest land provided an average of 1.6 gha of forest land biocapacity. However, this above-average biocapacity of cropland and forest land does not indicate sustainability. The country’s total ecological footprint is far higher than its total biocapacity.

In 2022, the U.S. ecological footprint of production was over 2.5 billion gha. This was similar to the ecological footprint of consumption, because the footprints of imports and exports were nearly equal. However, there were differences among the footprint components of imports and exports. The carbon component was more prominent in the ecological footprint of imports, whereas the cropland component was more prominent in exports. This means the United States imported more carbon-intensive goods and services than it exported, and exported more cropland-intensive harvests than it imported.
U.S. Trends: Better or Worse?

One good sign is that total U.S. biocapacity has been increasing over time. In 1961, total biocapacity was just over 1 billion gha, and by 2024, biocapacity had grown to 1.3 billion gha (2023 and 2024 data were forecasted).1 This is because of increases in agricultural productivity. Biocapacity is a measure of what the environment can provide for human use, not of biodiversity or ecosystem health. In fact, it has a negative correlation with biodiversity indicators. Cropland illustrates this tension well, as using fertilizers and chemicals can increase agricultural productivity at the expense of ecosystem health.

The U.S. population has also been increasing over time, which has decreased biocapacity per person. In 1961 biocapacity was 5.7 gha/person, and in 2022 was 3.8 gha/person.

Meanwhile, the U.S. ecological footprint of consumption has been increasing. In 1961 it was 1.6 billion gha, and by 2024 it reached 2.5 billion gha. Counteracting that increase to some degree is the per-person ecological footprint of consumption, which has decreased in recent years. In 1961, it was 8.9 gha/person, and in 2022, it was 7.9 gha/person. Although this is not a huge reduction, it provides a glimmer of hope that the country can reduce its footprint per person to offset population growth. However, it would need a very sizeable reduction to retreat to the safe operating space of its biocapacity.

In summary, the best available ecological footprint and biocapacity science reveals that the United States is exceeding a sustainable level of resource use for the production and consumption of goods and services. In 2022, the ecological footprint of consumption was 7.9 gha/person, and biocapacity was 3.8 gha/person. Ecological footprint is more than double biocapacity, meaning that economic activity is (over) two times the amount the United States can sustain. And with its outsized carbon footprint, the American economy is impacting the biocapacity of ecosystems on Earth.
Diving Into the Footprint Details

The carbon component makes up 64 percent of the ecological footprint embodied in the consumption of goods and services in the United States. Almost all of this carbon component (95 percent) comes from fossil fuel emissions. The largest share of these emissions (37 percent) comes from transport, of which road transport constitutes the majority. The next-largest share of U.S. carbon emissions (34 percent) comes from public and private utility companies producing electricity and heat for sale to third parties.

For many people, these details highlight the importance of decarbonizing electricity and heat generation and shifting transportation to less emissions-intensive modalities, such as rail. However, the emissions reductions needed to bring the United States back within its biocapacity are so immense that “green” alternatives aren’t sufficient. Americans must also reduce consumption of electricity and heat, as well as the distance they travel, because “green growth” is not possible.

In 2022, cropland made up 18 percent of the U.S. ecological footprint of consumption. Of the cropland ecological footprint, 84 percent was used for crops consumed by people and pets, 15 percent was used to feed livestock, and less than 0.5 percent was used to feed fish. Almost 700 million metric tons of crops were harvested, and just over half was maize. The second most harvested crop was soybeans at 17 percent of total harvests.

Yet the proportion of ecological impact does not equal the proportion of total harvests. For instance, maize made up 52 percent of crop harvests (metric tons) and 43 percent of the cropland ecological footprint of production (gha) in 2022. On the other hand, soybeans accounted for 17 percent of harvests (metric tons) and 32 percent of cropland ecological footprint of production (gha). Therefore, soybeans had almost double the ecological impact per metric ton of harvest in the United States.
The United States in the Global Context

The United States consumes far more than its share of the Earth’s natural resources. The global average ecological footprint of consumption was 2.7 gha/person in 2022. The United States crushed that benchmark at 7.9 gha/person. The average U.S. citizen consumed resources at almost three times the rate of the average global citizen.

Here’s another way of thinking about this: The United States is responsible for twelve percent of the world’s ecological footprint of consumption. Yet the U.S. population only amounts to four percent of the world population. This represents a highly disproportionate environmental impact.

The U.S. ecological footprint per person is even higher than that of most other high-income countries. The average ecological footprint of consumption in high-income countries is 6.1 gha/person.

There are important debates about best practices for presenting ecological footprint and biocapacity data. Often, the ecological footprint of a territory is compared to the biocapacity of that territory. For example, U.S. ecological footprint is compared to U.S. biocapacity. This implies that a country achieves sustainability if its ecological footprint is lower than its biocapacity.

Many criticize this approach as an unfair representation of sustainability, because some countries are blessed with exceptionally high biocapacity. For instance, in 2022, the ecological footprint in Canada was 8.4 gha/person, and the biocapacity was 14.4 gha/person. Canada’s biocapacity was clearly higher than its ecological footprint. However, its ecological footprint per person was in the top ten highest in the world. Therefore, perhaps it is also important to compare a country’s ecological footprint to world average biocapacity (global ecological balance) in addition to the country’s biocapacity (local ecological balance).

In 2022, global biocapacity was 1.5 gha/person, significantly lower than the U.S. ecological footprint of 7.9 gha/person. In other words, U.S. citizens consume resources and emit carbon at five times the global average sustainable rate.

Ecological footprint and biocapacity data illustrate that we are using natural resources and releasing waste at unsustainable rates, in the United States and around the world. It shows that this has been happening for decades. The United States and other high-income countries are disproportionately responsible for this state of overshoot. They must pump the brakes on resource consumption and waste emissions if we are to exist within local and global sustainable limits. They must pump the brakes, in other words, on the economy.


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Vídeomensagem de Brian Czech explicando o conceito Trophic Theory of Money

sábado, 7 de janeiro de 2023

Documentário - The Scientist's Warning (legendado)


P.S. Clique em "definições" e seleccione legendas em "Português"

O "Aviso dos Cientistas Mundiais à Humanidade" foi um documento escrito em 1992 por Henry W. Kendall e assinado por cerca de 1.700 cientistas de renome. Vinte e cinco anos depois, em novembro de 2017, 15.364 cientistas assinaram o "Aviso dos Cientistas Mundiais à Humanidade: Um Segundo Aviso" escrito por William  Ripple.

William Ripple é o principal autor do "Global Scientists' Warning to Humanity: A second Notice", publicado em 13 de novembro de 2017. Este artigo inclui 15.364 co-signatários cientistas de 184 países. O artigo sugere que "para evitar a miséria generalizada e a perda catastrófica da biodiversidade, a humanidade deve praticar uma alternativa mais ambientalmente sustentável aos negócios como sempre". Em 2020, a Ripple liderou o Alerta dos Cientistas Mundiais sobre uma Emergência Climática, declarando com mais de 11.000 co-signatários cientistas de 153 países que "o planeta Terra está enfrentando uma emergência climática" e apresentando seis etapas para evitar os piores efeitos  das Alterações Climáticas.

Além de ser um pesquisador altamente citado,Ripple é o diretor da Alliance of World Scientists, uma organização independente com mais de 25.000 membros cientistas que atua como uma "voz coletiva internacional de muitos cientistas em relação ao clima global e às tendências ambientais. "

Advertência dos Cientistas do Mundo à Humanidade: um Segundo Aviso (Texto em Português)