Explore the latest insights from top science journals in the Muser Press daily roundup (September 2, 2025), featuring impactful research on climate change challenges.
In brief:
Changing wind patterns caused upwelling failure in the Gulf of Panama
The natural phenomenon of upwelling, which occurs annually in the Gulf of Panama, failed for the first time on record in 2025.
A study led by scientists from the Smithsonian Tropical Research Institute (STRI) and the Max Planck Institute for Chemistry indicates that the weakening of the trade winds was the cause of this event. This finding highlights the climate’s impact on fundamental oceanic processes and the coastal communities that depend on them.
During the dry season in Central America, northern trade winds generate upwelling events in the ocean waters of the Gulf of Panama. Upwelling is a process that allows cold, nutrient-rich waters from the depths of the ocean to rise to the surface. This dynamic supports highly productive fisheries and helps protect coral reefs from thermal stress. Thanks to this movement of water, the sea along Panama’s Pacific beaches remains cooler during the summer season.
Scientists from the Smithsonian Tropical Research Institute (STRI) and the Max Planck Institute for Chemistry have studied this phenomenon. Their records show that this seasonal upwelling, which occurs from January to April, has been a consistent and predictable feature of the gulf for at least 40 years. However, recently researchers recorded that in 2025, this vital oceanographic process did not occur for the first time. As a result, the typical drops in temperature and spikes in productivity during this time of year were diminished.
In the recently published article in the journal PNAS, scientists suggest that a significant reduction in wind patterns was the cause of this unprecedented event, revealing how climate disruption can quickly alter fundamental oceanic processes that have sustained coastal fishing communities for thousands of years.
No upwelling in 2025 due to less wind
Over the last 40 years, a continuous data set from the Physical Monitoring Program at STRI on the temperature of the surface waters of the tropical eastern Pacific Ocean off Panama shows a consistently recurring seasonal upwelling event up to and including 2024. In addition, the MPI for Chemistry’s research yacht S/Y Eugen Seibold has been repeatedly collecting water samples and physical data on temperature and wind conditions since 2023.
Analysis of these data sets showed that the trade winds in 2025 were not sufficient to break up the stratification of the sea surface and trigger upwelling. “For the first time, we have observed how changes in an atmospheric and oceanic circulation system exceed a threshold and lead to reduced biological production,” says Ralf Schiebel, group leader at the Max Planck Institute for Chemistry.
The lack of upwelling currents led to a failure in nutrient supply and correspondingly low algae growth, which has an impact on marine food webs and leads to a decline in commercial fishing, explains Ralf Schiebel. However, further research is needed to determine the exact cause and the possible consequences for fisheries.
“It is too early to conclude that the current climate and ocean warming could lead to reduced upwelling in the tropical eastern Pacific,” says Gerald Haug, Director of the Climate Geochemistry Department at the Max Planck Institute for Chemistry.
However, the study highlights the growing vulnerability of tropical upwelling systems, which, despite their enormous ecological and socioeconomic importance, remain poorly monitored, summarize the researchers involved in the study. It also underscores the urgency of strengthening ocean-climate observation and prediction capabilities in the planet’s tropical regions.
Therefore, the research yacht S/Y Eugen Seibold is currently sailing in the tropical eastern Pacific Ocean and is currently off the Galapagos Islands collecting data and samples.
Journal Reference:
O’Dea, A., Sellers, A. J., Pérez-Medina, C., Pardo Díaz, J., Guzmán Bloise, A., Pöhlker, C., Chiliński, M. T., Aardema, H. M., Cybulski, J. D., Heins, L., Paton, S. R., Slagter, H. A., Schiebel, R., & Haug, G. H., ‘Unprecedented suppression of Panama’s Pacific upwelling in 2025’, Proceedings of the National Academy of Sciences U.S.A. 122, e2512056122 (2025). DOI: 10.1073/pnas.2512056122
Article Source:
Press Release/Material by Max Planck Institute for Chemistry (MPIC)
Thawing permafrost raised carbon dioxide levels after the last ice age
For a long time, it was the shifts between ice ages and interglacial periods that determined how much carbon dioxide was in the atmosphere. During ice ages, CO₂ levels fell, only to rise by around 100 ppm (parts per million) during interglacial periods. Previously, the main reason for this was thought to be that warmer and more mixed oceans cannot store as much carbon and therefore release it into the atmosphere between ice ages.
However, new research from the University of Gothenburg shows that thawing permafrost may have accounted for a significant proportion of carbon dioxide emissions.
“We have concluded that land north of the Tropic of Cancer, 23.5 degrees north, emitted a lot of carbon when the average temperature rose in the northern hemisphere after our last ice age. We estimate that this carbon exchange may have accounted for almost half of the rising carbon dioxide levels in the atmosphere,” says Amelie Lindgren, researcher in ecosystem science at the University of Gothenburg.
Carbon froze into the ground
Researchers believe that large amounts of carbon were stored during the Ice Age when grass and other plants simply froze into the ground, with wind-borne rock dust settling on top. Such deposits, known as ‘loess’, are created during ice ages and can reach tens of metres in thickness. They are found across large areas of Europe and Asia, but also in North America.
Permafrost is required for the trapping of organic material in these deposits, and even normal soil with permafrost contains more organic carbon than unfrozen soil because the cold slows decomposition rates.
Pollen analyses
By combining analyses of pollen from the last 21,000 years with climate data from models, the researchers have been able to estimate the types of vegetation that existed in different places throughout history.
“We have chosen to take a snapshot every thousand years. Once we know what type of vegetation prevailed, we can estimate how much carbon were stored in the soil. In this way, we can model how carbon exchange between the soil and the atmosphere has looked since the last ice age,” says Lindgren.
Around 21,000 years ago, the continental ice sheets reached their maximum extent in the northern hemisphere. The whole of Scandinavia and what is now Canada were covered by ice at that time, and permafrost prevailed in large parts of Siberia, China and parts of central Europe. During the period 17,000–11,000 years ago, it became warmer. This led to the thawing of the permafrost, which resulted in increased emissions of CO₂ from the ground to the atmosphere.
Natural variation
Previous analyses of ice cores show that the carbon dioxide content in the atmosphere rose as follows:
- 180 ppm (parts per million) CO₂ 21,000 years ago, when the ice age reached its peak.
- 270 ppm CO₂ 11,000 years ago, during a normal interglacial period.
According to researchers, this is a natural variation between ice ages and interglacial periods. However, despite the shrinking ice sheet and continued thawing of new areas of permafrost, the carbon dioxide content did not rise much more after that.
“We see that peatlands stored large amounts of carbon during the Holocene. Over time, the uptake in peatlands has actually compensated for the emissions that occurred from the permafrost,” says Amelie Lindgren.
Humans disrupt the carbon cycle
However, over the past 250 years, humans have disrupted the natural carbon cycle by burning large amounts of fossil carbon, mainly coal and oil. Since the Industrial Revolution in the 19th century, the carbon dioxide content in the atmosphere has increased from 280 ppm to 420 ppm today.
“There are extremely high levels of carbon dioxide in the atmosphere right now, and the permafrost is thawing as temperatures rise. What helped us the last time the permafrost decreased was increased carbon storage in peatlands and new land areas becoming available when the continental ice sheets retreated. In the future, we will have less land due to sea level rise, and it is difficult to see where we will store the carbon that will be released,” Lindgren concludes.
Journal Reference:
Amelie Lindgren, Peter Kuhry, Max Holloway, Zhengyao Lu, George Tanski, and Gustaf Hugelius, ‘Massive losses and gains of northern land carbon stocks since the Last Glacial Maximum’, Science Advances 11, 35: eadt6231 (2025). DOI: 10.1126/sciadv.adt6231
Article Source:
Press Release/Material by University of Gothenburg
New DNA test reveals plants’ hidden climate role
Few of us ever think about what happens beneath our feet when we walk through a field of wheat or clover. We see the stalks, leaves, and flowers, but in practice we have no direct access to the roots.
Roots, however, are central. They anchor plants in the soil, supply them with water and nutrients, and contribute to carbon storage in the ground. But because roots are hidden, researchers have for decades struggled to measure how much biomass lies below and how it is distributed among species.
“We have always known that roots are important, but we have lacked a precise tool to measure them. It’s a bit like studying marine ecosystems without ever being able to dive beneath the surface of the water,” says Henrik Brinch-Pedersen, professor at the Department of Agroecology, Aarhus University.
From muddy boots to genetic fingerprints
Until now, researchers typically measured roots by digging up large soil samples, washing the roots free, drying, and weighing them. This is a lengthy process, and the finest roots are often destroyed along the way. That is a major problem, since fine roots are the most active in absorbing nutrients and releasing carbon to the soil environment.
The new method is instead based on droplet digital PCR (ddPCR), a DNA technology in which a soil sample is divided into tens of thousands of microscopic droplets, each of which is analyzed for the presence of DNA.
The researchers use a genetic marker called ITS2, which works like a fingerprint for each species. In this way, they can not only see that roots are present but also identify which species they belong to and how much biomass they represent.
“It’s a bit like giving the soil a DNA test,” says Henrik Brinch-Pedersen. “We can suddenly see the hidden distribution of species and biomass without digging up the whole field.”
International recognition
The method was developed by a research team consisting of Nurbanu Shynggyskyzy, Claus Krogh Madsen, Per L. Gregersen, Jim Rasmussen, Uffe Jørgensen, and Henrik Brinch-Pedersen. It has been published in the renowned journal Plant Physiology and has already received special attention in an accompanying News & Views article, where international experts highlight it as a breakthrough.
What can it be used for?
The new technology opens up a wide range of applications:
- Climate research: Accurately measuring how much carbon different crops store in the soil is crucial for documenting and improving agriculture’s climate contribution;
- Plant breeding: The method enables researchers to select varieties that send more biomass belowground without reducing aboveground yields;
- Biodiversity: In grasslands and mixed crops, it is now possible to see how species compete or cooperate underground, something that was almost impossible before.
“We see great potential in using this method to develop varieties that store more carbon in the soil. It could become an important tool in future agriculture,” says Henrik Brinch-Pedersen.
Roots as a climate solution
It is no coincidence that researchers are focusing on roots. While we usually think of wind turbines and electric cars as climate solutions, plant root systems also hold great potential in the form of biological carbon storage.
When plants grow, they draw CO₂ from the atmosphere and send part of the carbon into their roots. There, it can remain stored in the soil for decades, or even centuries, if we can develop cropping systems that maximize this potential.
Without precise measurement tools, however, it has been difficult to document the effect. This is where the new DNA technology could become a gamechanger.
Limitations and next steps
The method is not without challenges. For example, genetic hybrids such as ryegrass and Italian ryegrass can be difficult to distinguish because their DNA is so similar. And the method requires developing specific DNA probes for each species researchers wish to measure.
“For us, the most important thing is that we have shown it can be done. That is the foundation we can build upon. Our vision is to expand the DNA library so that in the future we can measure many more species directly in soil samples,” says Henrik Brinch-Pedersen.
Where researchers previously depended on time-consuming fieldwork, the new method allows root analysis to be carried out quickly, precisely, and on a much larger scale.
That means researchers can now take a precise look into the underground world that has so far remained hidden.
Journal Reference:
Nurbanu Shynggyskyzy, Claus Krogh Madsen, Per L Gregersen, Jim Rasmussen, Uffe Jørgensen, Henrik Brinch-Pedersen, ‘Digital PCR enables direct root biomass quantification and species profiling in soil samples’, Plant Physiology 198, 3: kiaf276 (2025). DOI: 10.1093/plphys/kiaf276
Article Source:
Press Release/Material by Camilla Brodam Galacho | Aarhus University (AU)
Featured image credit: Gerd Altmann | Pixabay
