Flux continu

The ecological concept of human carrying capacity is necessarily complicated because human beings are the ‘ultimate ecosystem engineers’ who moderate the environment for their benefit. For at least the last few hundred years, human ingenuity, access to massive stocks of fossil fuels, and technological development have driven facilitation whereby increasing human abundance has promoted higher population growth rates. However, this positive relationship broke down during the 1950s, and by 1962, the global human population entered a phase where the growth rate consistently declined as population increased. The onset of this negative phase occurred 8 years before a global biocapacity deficit began in 1970. The onset of the negative phase also varies regionally, with the lowest-income and highest fertility regions entering this phase later than higher-income regions. A Ricker logistic model fitted to the negative phase predicts that the global population could reach 11.7–12.4 billion people between 2067 and 2076.

“The battle to feed all of humanity is over,” Stanford biologist and ecologist Paul Erhlich declared on the first page of his 1968 best-seller, “The Population Bomb.” Because the “stork had passed the plow,” he predicted, “hundreds of millions of people are going to starve to death.”

Exclusive: Intelligence officers say Russian campaign could intensify ‘in months, not years’ – but that panic risks playing into Kremlin psy-ops

Exclusive: Federal government court filings claim internal company documents included warnings about products being toxic

If you’re always above average, it’s probably time to redefine what’s normal. The new normal for Earth’s climate is systematically rising temperatures.

The Prairieland case is about more than eight defendants. It is about the dangerous precedent being built around protest, political identity, and dissent.

The British-Canadian computer scientist often touted as a “godfather” of artificial intelligence has shortened the odds of AI wiping out humanity over the next three decades, warning the pace of change in the technology is “much faster” than expected. Prof Geoffrey Hinton, who this year was awarded the Nobel prize in physics for his work in AI, said there was a “10% to 20%” chance that AI would lead to human extinction within the next three decades.

Global effort needed to limit effects of pollution, industrial fishing and climate crisis, World Ocean Assessment says

The Gulf Stream is part of the Atlantic Meridional Overturning Circulation (AMOC). The AMOC is a tipping element and may collapse under changing forcing. However, the role of the Gulf Stream in such a tipping event is unknown. Here, we investigate the link between the AMOC and Gulf Stream using a high-resolution (0. 1°) stand-alone ocean simulation, in which the AMOC collapses under a slowly-increasing freshwater forcing. AMOC weakening gradually shifts the Gulf Stream near Cape Hatteras northward, followed by an abrupt northward displacement of 219 km within 2 years. This rapid shift occurs a few decades before the simulated AMOC collapse. Satellite altimetry shows a significant (1993–2024, p < 0.05) northward Gulf Stream trend near Cape Hatteras, which is also confirmed in subsurface temperature observations (1965–2024, p < 0.01). These findings provide indirect evidence for present-day AMOC weakening and demonstrate that abrupt Gulf Stream shifts can serve as early warning indicator for AMOC tipping.

There is mounting experimental evidence that lifetime exposure to increasing atmospheric CO2 levels can negatively impact the normal physiology of organisms. Directly assessing this in humans is very difficult. We analysed serum bicarbonate (HCO3−), calcium (Ca) and phosphorus (P) from 1999 to 2020 as indirect proxies for atmospheric CO2 exposure. Over this period, average bicarbonate levels in this population show an increasing trend which parallels rising atmospheric CO2 concentrations. Both. If these trends continue, blood bicarbonate values could be at the limit of the accepted healthy range in half a century, and Ca and P will be at the limit of their healthy ranges by the end of this century. This has the potential to cause a range of adverse health effects.