human impact

Heatwaves and major carbon emitters

October 24, 2025 By EarthWise Leave a Comment

A new study by ETH Zurich, one of the world’s leading universities in science and engineering, demonstrates that human-induced climate change greatly increased the likelihood and intensity of over 200 global heatwaves between 2000 and 2023. Emissions associated with each of the 180 largest producers of fossil fuels and cement contributed substantially to these events. Emissions from these so-called carbon majors accounted for 60% of humanity’s total cumulative CO₂ emissions from 1850 to 2023.

The research looked at 213 heatwaves that occurred on all seven of Earth’s continents between 2000 and 2023. The study calculated how climate change affected the intensity and likelihood of each heatwave.

According to the study, global warming made heatwaves 20 times more likely between 2000 and 2009, and as much as 200 times more likely between 2010 and 2019, compared with the period between 1850 and 1900.

Estimates are that the 180 carbon majors are responsible for about half of the change in global mean surface temperature over time. Furthermore, 14 of these 180 entities made the same contribution to climate change as the remaining 166 organizations combined.

While every one of us – individuals, countries, or companies – contributes to climate change, the carbon majors have especially significant responsibility.

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Rising heat waves tied to fossil fuel and cement production

Photo, posted May 1, 2019, courtesy of Martin Snicer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The human impact on oceans

October 21, 2025 By EarthWise Leave a Comment

Vast and powerful, the oceans have sustained human life around the world for millennia. They provide food, natural resources, and livelihoods, supporting countless communities and economies. But despite their size and resilience, the oceans are under increasing pressure from climate change and human activity, pushing them toward a dangerous threshold.

According to a new study led by researchers from UC Santa Barbara, the cumulative human impact on the oceans is forecasted to double by 2050, which is just 25 years from now. These impacts include ocean warming, fisheries losses, sea level rise, acidification, and pollution.

The research team, which includes collaborators from Nelson Mandela University in South Africa, found that the tropics and poles will experience the fastest rate of change. And coastal regions, where most human activity takes place, will bear the heaviest consequences of those changes.

The research team calls the findings sobering – not only because the impacts are increasing, but because they’re increasing so quickly.

The study, which was recently published in the journal Science, shows that ocean warming from climate change and reductions in marine biomass from overfishing are expected to be the two largest contributors to future ocean impacts. If ecosystems cannot cope with these pressures, human societies will also feel the consequences.

But the research team stresses that it’s not too late. Stronger climate policies, better fisheries management, and protections for vulnerable habitats like salt marshes and mangroves could help slow or even reduce human impacts.

The research serves as both a warning, and a chance to act before it’s too late.

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Human impact on the ocean will double by 2050, UCSB scientists warn

Photo, posted July 11, 2018, courtesy of Ed Dunens via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biosphere integrity

October 14, 2025 By EarthWise Leave a Comment

Civilization has an enormous need to utilize the biosphere, that is, the regions of the surface, atmosphere, and bodies of water of the earth occupied by living organisms. The biosphere supplies us with food, raw materials, and increasingly, climate protection.

A study by two European universities looked at functional biosphere integrity, which is essentially the plant world’s ability to regulate the state of the Earth system. Functional biosphere integrity faces massive human interference from consumption of resources, biodiversity loss, and climate change.

Highly detailed analysis modeled water, carbon, and nitrogen flows at a fine resolution over the entire planet and provided a detailed inventory year-by-year since the year 1600. Each area is then assigned a status based on its tolerance limits of ecosystem change. An area can either be a Safe Operating Space, a Zone of Increasing Risk, or a High-Risk Zone.

As the Industrial Revolution took hold, the proportion of global land area where ecosystem changes went beyond the locally defined safe zone, increased. The current analysis shows that 60% of global land areas are now out of the safe operating space and 38% are facing high risk.

Human demand for biomass continues to grow. The Earth system is increasingly stressed as humanity channels it into its own uses through harvested crops, residues, and timber. At the same time, photosynthesis activity is reduced by land cultivation and sealing off land with construction. We are not good for the biosphere.

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60 percent of the world’s land area is in a precarious state

Photo, posted September 14, 2024, courtesy of Jan Helebrant via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio