Global warming, climate change, all these things are just a dream come true for politicians. I deal with evidence and not with frightening computer models because the seeker after truth does not put his faith in any consensus. The road to the truth is long and hard, but this is the road we must follow. People who describe the unprecedented comfort and ease of modern life as a climate disaster, in my opinion have no idea what a real problem is.
Young impressionable adults at university are deep in the motherlode of leftist extremism. The good news is that despite that, many still have some grip on reality. The bad news is almost none of them feel like they can say it — not to their teachers, and not to other students, and about half the time, not even to their girlfriends and boyfriends. University is teaching them something after all: how to pretend to conform, and how to hide their opinion.
So, when asked, an amazing 88% of all students admitted they had pretended to hold more progressive views on campus than they truly felt. 80% had even submitted assignments that misrepresented their own views in order to fit in with their professors opinions. For some, they did it so often, it was second nature.
Imagine the effect on lecturers and researchers of being surrounded by “yes” men and gushing girls? They would be free to come up with the most grandiose mental Zeppelins surrounded by fairy floss with nary a single live spark to pop the balloon before it launched with passengers.
It is the feedback loop from hell. Every student who fakes agreement makes the orthodoxy look more popular than it really is. Other students see the synthetic consensus and stay silent. Hallowed Professors feel like Gods, certain their ideas are self-evidently correct. A small fake consensus begets a bigger fake consensus.
This lack of free speech on campus was what killed Jason Arday. Cambridge needed to hear from the skeptics of Woke orthodoxy ten years ago. They would have poked holes in the fashionable dogmas before reputations were cast in stone and the stakes became catastrophically, tragically high.
Between 2023 and 2025, we conducted 1,452 confidential interviews with undergraduates at Northwestern University and the University of Michigan.
We asked: Have you ever pretended to hold more progressive views than you truly endorse to succeed socially or academically? An astounding 88 percent said yes.
This dissonance shows up everywhere. Seventy-eight percent of students told us they self-censor on their beliefs surrounding gender identity; 72 percent on politics; 68 percent on family values. More than 80 percent said they had submitted classwork that misrepresented their views in order to align with professors. For many, this has become second nature — an instinct for academic and professional self-preservation.
So even in some of the most gender fluid institutions on Earth, only 7% “believe” gender is a broad spectrum.
Eighty-seven percent identified as exclusively heterosexual and supported a binary model of gender. Nine percent expressed partial openness to gender fluidity. Just seven percent embraced the idea of gender as a broad spectrum, and most of these belonged to activist circles.
It’s a social thing almost as much as a career-related issue. Three quarters of students don’t even tell close friends their real personal views on some topics. And “nearly half” don’t tell their intimate partners (which probably means mostly men are keeping their political opinions quiet around their girlfriends. As many as 40% of young women in the US identify as Liberal or very Liberal, while only 25% of young men did.)
Seventy-three percent of students reported mistrust in conversations about these values with close friends. Nearly half said they routinely conceal beliefs in intimate relationships for fear of ideological fallout.
We know that biological men playing women’s sports is an 80:20 issue — an issue where 80% of the population feel the same way (even at university). Out in the real world, it’s probably a 90:10 thing.
Perhaps most telling: 77 percent said they disagreed with the idea that gender identity should override biological sex in such domains as sports, healthcare, or public data — but would never voice that disagreement aloud. Thirty-eight percent described themselves as “morally confused,” uncertain whether honesty was still ethical if it meant exclusion.
Authenticity, once considered a psychological good, has become a social liability. And this fragmentation doesn’t end at the classroom door. Seventy-three percent of students reported mistrust in conversations about these values with close friends. Nearly half said they routinely conceal beliefs in intimate relationships for fear of ideological fallout. This is not simply peer pressure — it is identity regulation at scale, and it is being institutionalized.
Marvel that somehow despite the non stop agitprop for the last ten formative years, 87% of young adults at these two universities still feel heterosexual. It could be worse.
But when those who ask hard questions are not rewarded, each generation of professors become more absurd than the last. The smartest students know they won’t fit it with academia, and only the most obedient stick around.
In that case, science doesn’t even progress one funeral at a time.
New method maps tides at much finer local scales using decades of satellite images.
The new beach- scale tidal method (and the underlying CoastSat shoreline data) is explicitly positioned as a useful tool for studying sea- level rise and coastline change.
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New method maps tides at much finer local scales using decades of satellite images.
Researchers from DTU Space (Technical University of Denmark), in collaboration with the University of Oxford, Technical University of Munich (TUM), and others, have developed a technique that extracts detailed tidal information directly from satellite photographs of coastlines.
Traditional tide gauges are often spaced 50 km or more apart, leaving large gaps. Satellite altimetry also struggles near the coast.
The new approach treats the beach itself as a giant ruler:
It tracks the land- water boundary (shoreline position) across thousands of Landsat satellite images spanning more than 40 years.
By combining the movement of that waterline with the known slope of the beach, researchers convert horizontal shoreline shifts into vertical water- level (tidal) changes.
This yields tidal estimates every ~100 metres along the coast, far denser than previous methods.
Tide heights are not uniform. In some places they can differ by nearly 1 metre across a single bay only a few tens of kilometres long (for example, New Zealand’s South Taranaki Bight). These local variations matter for flood risk, coastal planning, and navigation.
The method turns what was previously treated as “noise” in satellite shoreline data into a useful signal for high- resolution tidal mapping, especially valuable in sparsely instrumented or remote coastal areas.
The study was published in Communications Earth & Environment (Nature portfolio). Professor Ole Baltazar Andersen of DTU Space is a co- author; Michael Hart- Davis (TUM) is the lead author.
CoastSat is an open- source Python toolkit (developed by Kilian Vos and colleagues at the University of New South Wales) that automatically extracts time series of shoreline positions from publicly available satellite imagery. It is optimized for sandy beaches and has been widely used for coastal monitoring worldwide.
Core Methodology (Step-by- Step)
Image Retrieval
Uses Google Earth Engine to download Top- of- Atmosphere reflectance images.
User defines a region of interest (polygon) and date range. Images are cropped to that area.
Pre- processing
Cloud masking (removes cloudy pixels).
Pansharpening (for Landsat 7/8/9) to enhance spatial resolution.
Down-sampling or re- projection of bands so all images have consistent resolution (typically ~10- 15 m after processing).
Filtering based on a cloud- cover threshold.
Image Classification
A supervised Multilayer Perceptron (neural network) classifier labels every pixel into one of four classes:
Sand
Water
White-water (breaking waves / foam)
Other land features (vegetation, rocks, buildings, etc.)
The classifier was trained on thousands of manually labelled pixels from diverse beaches.
Shoreline Detection
Computes the Modified Normalized Difference Water Index (MNDWI):
Applies an image- specific Otsu threshold on the MNDWI values (restricted to the sand and water classes) to optimally separate land and water.
Uses a marching- squares algorithm for sub-pixel resolution contouring of the waterline. This finds the precise sand- water interface rather than just the nearest pixel edge.
Time- Series Generation
The detected waterline (instantaneous shoreline) is intersected with a series of shore- normal transects (typically spaced every 100 m or user- defined).
This produces a cross- shore position time series at each transect.
Optional tidal correction can be applied later using a tide model (e.g., FES) and an estimated beach slope to convert the instantaneous waterline into a fixed-datum shoreline (e.g., mean sea level).
Accuracy
Horizontal accuracy is typically ~8-12 m (root-mean- square error) when validated against ground surveys.
Sub- pixel waterline detection itself is on the order of ~5 m for Landsat.
Suitable for detecting changes larger than ~10- 15 m; smaller variations are generally within the noise.
Key Strengths
Fully automated and scalable to any sandy coastline with available imagery.
Provides multi- decadal records (40+ years in many places).
Open- source and designed to be usable by non-experts via Jupyter notebooks.
Limitations
Best suited to sandy beaches (performance degrades on rocky, muddy, or heavily vegetated coasts).
Affected by cloud cover, image quality, and extreme white- water conditions.
Instantaneous waterlines still contain tidal, wave setup, and runup effects until corrected.
CoastSat is freely available on GitHub (kvos/CoastSat) and underpins large regional datasets, including the Pacific Rim shoreline collection used in the recent beach- scale tidal variation study.
The new beach- scale tidal method (and the underlying CoastSat shoreline data) is explicitly positioned as a useful tool for studying sea- level rise and coastline change.
Traditional tide gauges are sparse (often tens of kilometres apart) and satellite altimetry struggles close to the coast. The CoastSat- based approach fills those gaps by turning the moving waterline on the beach into a local sea-level record:
Satellite images capture the instantaneous position of the sand– water boundary.
Combined with the beach slope, the horizontal movement of that waterline is converted into a vertical water-level (tidal and sea-level) signal.
Because the Landsat record spans 40+ years (1984- present), researchers can examine both short- term tidal patterns and longer- term changes.
Specific value for sea-level rise research
Local tidal characterisation Accurate knowledge of local tides is essential for converting raw shoreline positions into a consistent vertical datum (e.g., mean sea level). Without it, tidal “noise” can mask or distort true shoreline trends caused by sea- level rise, storms, or sediment processes.
Detecting changes in tides themselves As mean sea level rises, tidal amplitudes and phases can change (especially in shallow coastal and estuarine areas). The multi- decadal shoreline time series allow researchers to look for trends in major tidal constituents (such as the dominant M₂ tide) at beach scale, something previously difficult outside of well-instrumented sites.
Improved shoreline-change analysis Once the tidal component is properly accounted for, the remaining shoreline movement better reflects true morphological change (erosion/accretion) driven by sea-level rise, waves, and human interventions. This is critical for projecting future coastline retreat.
Gap-filling in data- poor regions Many coastlines lack long-term tide gauges. The method can provide high- resolution (≈100 m) tidal information almost anywhere there are sandy beaches and sufficient satellite coverage, supporting better local sea-level and flood- risk assessments.
Limitations to keep in mind
Accuracy depends on good beach- slope estimates and image quality.
It works best on open sandy beaches; complex or rocky coasts are more challenging.
Long-term trends in the tidal constituents extracted this way still need careful validation against traditional gauges and altimetry because of residual measurement noise and morphological changes.
In short, by treating the beach as a natural “tide gauge,” the method turns an existing global archive of satellite images into a new source of coastal water- level information, useful both for understanding present- day tides and for improving studies of how coastlines respond to rising seas.
Beach scale tidal variations observed from satellite- derived shoreline time series
Tides can vary significantly even over short distances along the coast. Using more than 40 years of Landsat satellite images (via the CoastSat shoreline dataset), the team mapped tidal variations at ~100-metre resolution along Pacific Rim beaches.
Example results:
In New Zealand’s South Taranaki Bight (~90 km long), tidal height differed by nearly 1 metre from one end of the bay to the other.
Around Christchurch, tides in Pegasus Bay were about 40 cm higher than those south of the city near the Rakaia River.
Instead of treating the moving shoreline in satellite photos as noise (the usual approach when studying beach erosion), the researchers treated it as the signal.
By tracking the waterline position and combining it with beach slope information, they converted horizontal shoreline shifts into vertical tidal height changes. This works even in areas without local tide gauges.
The method recovers major tidal constituents (especially the dominant M₂ tide) and matches well with traditional tide gauges, ocean tide models, and newer wide-swath satellite data (e.g., SWOT).
Most existing tide information is either sparse (tide gauges every 50+ km) or coarse near the coast. This approach fills those gaps at beach scale and has implications for:
Local flood- risk assessment
Coastal planning and engineering
Improving tide models
Studying long- term changes in tidal amplitudes
The full open- access paper is available at the Nature.
Coastal tidal dynamics play a crucial role in a variety of biogeophysical processes, ranging from compound flooding to sediment transport. Satellite altimetry has revolutionized our understanding of ocean tides, but coastal regions remain challenging for satellite altimetry-based observations. In recent years, important efforts have been made to produce shoreline measurements from satellite optical imagery. These datasets raise the question of whether shoreline observations can resolve tidal dynamics at fine coastal scales. Here, we show that shoreline measurements provide fine-scale insights into tidal characteristics, demonstrating variability at beach scales across the Pacific Rim. We explore how both harmonic analysis and response-based methods can be applied to these data to study a range of tidal constituents. Our results are contrasted with in situ measurements and state-of-the-art models as well as with wide-swath satellite observations. We demonstrate that satellite-derived shoreline measurements are a valuable resource for tidal research, particularly for model validation and the study of tidal constituent variability in the coastal zone.
President Maumoon Abdul Gayoom had raised sea- level concerns at the UN and Commonwealth meetings around 1987– 88, describing a potential “death of a nation,” but those were political warnings rather than dated quantitative forecasts of total submersion by a specific year.
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No, the United Nations did not predict in 1988 that all 1,196 islands of the Maldives would drown between 2008 and 2018.
The UN- UNEP only planned a study at the time.
The specific claim is a misattribution of statements by Maldivian government officials reported in contemporary news coverage.
On 26 September 1988, an AFP report (published in Australia’s The Canberra Times and elsewhere) stated:
“A gradual rise in average sea level is threatening to completely cover this Indian Ocean nation of 1196 small islands within the next 30 years, according to authorities.”
Maldives Environmental Affairs Director Hussein Shihab was quoted saying an estimated rise of 20- 30 cm in the next 20- 40 years “could be ‘catastrophic’ for most of the islands, which were no more than a metre above sea level.”
The same report noted the United Nations Environment Programme was planning a study and mentioned a separate (also unrealized) concern that drinking- water supplies might dry up by 1992.
This was a statement from Maldivian officials (following severe flooding in 1987 that damaged the capital Malé), not a formal UN scientific prediction or IPCC assessment.
President Maumoon Abdul Gayoom had raised sea- level concerns at the UN and Commonwealth meetings around 1987– 88, describing a potential “death of a nation,” but those were political warnings rather than dated quantitative forecasts of total submersion by a specific year.
Early media and some expert commentary in the late 1980s sometimes framed low- lying atolls as potentially disappearing on multi- decade timescales under high- end sea- level scenarios of the era, but the precise “all islands gone by ~2018” wording traces to the 1988 AFP report of local authorities.
The Maldives still exist.
The islands have not been submerged.
Tourism infrastructure has expanded (including airport developments), and studies have documented that many reef islands have remained stable in area or grown through natural accretion and sediment processes, even as relative sea level has risen.
Sea level has risen. Local tide-gauge and other data show relative sea-level rise on the order of roughly 3+ mm/year in recent decades in the region (e.g., ~3.4 mm/year averages cited for periods including 1987- 2018). Global mean sea level has accelerated compared with the early 20th century.
The 20–30 cm rise referenced as potentially catastrophic has not occurred on that short timescale; cumulative rise since the late 1980s is substantially less.
Vulnerability remains real.
Most islands are very low- lying (typically <1–2 m above mean sea level).
Flooding, erosion, saltwater intrusion into freshwater lenses, and storm- related impacts are ongoing concerns. Longer- term projections (e.g., toward 2100) under higher- emission scenarios continue to flag substantial risks of inundation or uninhabitability for large portions of the archipelago without adaptation (seawalls, land reclamation, elevated structures, etc.).
Contemporary scientific estimates circulating in the late 1980s projected global sea- level rise on the order of tens of centimeters to a couple of meters over a century under various scenarios.
Maldivian officials and leaders highlighted the extreme vulnerability of their low- lying islands and used strong language about potential national catastrophe.
UNEP facilitated studies and the UN provided a forum, but there was no official United Nations prediction that the entire archipelago would be underwater by 2018.
The Maldives government has pursued adaptation and international advocacy on the issue for decades.
The Maldives hosted the Small States Conference on Sea Level Rise (14–18 November 1989).
The resulting Male Declaration on Global Warming and Sea Level Rise (transmitted to the UN) expressed deep concern about the threat of sea- level rise to low-lying island states, called for international cooperation, monitoring, and action (including support from UNEP, WMO, and others), and recognized the emerging IPCC process. It did not contain a prediction that the Maldives would drown by 2018.
A 1988 news report of Maldivian officials warning of potential catastrophic effects from modest sea- level rise within a few decades has been widely circulated (especially in skeptic commentary around 2018) as a failed “UN and experts predicted total drowning by 2018” claim.
The islands are still above water, sea level has risen more slowly than the most alarming short-term framing implied, and natural island dynamics plus human adaptation have so far prevented the worst outcomes of that particular warning.
It is adaptation time. Mitigation has failed, and no policy change, however radical, can affect global or regional climate for decades, if ever. As stated in a recent article in the New York Times:
Climate change means that the issue is most likely here to stay. Across Europe, “we think the summers are hot now,” said Joan Ballester Claramunt, a research professor at the Barcelona Institute for Global Health who focuses on climate change and health. “The future that we’re seeing, it could be much worse.”
So, why didn’t the alarmist community push for A/C and other appliances to cool the air during the summer peak? They warned about ‘hothouse Earth’ but did nothing about it.
Did climate mitigation policy work against adaptation directly and indirectly? Yes and yes. That is a major problem. In the name of social justice, climate campaigners are invited to replace wasteful, losing climate mitigation policies with here-and-now adaptation for the summer peak. For basic human needs. And now.
Alex Epstein has identified “climate mastery” as a feature of the modern energy sector (dense energies, only two centuries old). The EU/UK can do today what was done by, for example, Houstonians a century ago: adapt and thrive.
[Europe’s] green disavowal of air conditioning comes at an economic cost. As the mercury rises, business productivity suffers along with the workforce.
Europe was a set-up for heat waves:
Many European offices and apartment buildings were designed to retain heat, and air-conditioning penetration averages 19%, compared with some 90% in the U.S., according to a report this year by Allianz Research, an arm of the insurance company. One result: Even “indoor workers are not insulated” from the misery.
Policy implications?
Europe will face economic costs related to warming“even if ambitious climate mitigation goals are met,” says a report last year from Assessing Climate Change Risk in Europe, a European Union-funded research effort. But the continent can reduce the harm by better adapting. That study found broader AC adoption could have annual economic benefits of €40 to €60 billion ($46 billion to $69 billion) by 2050. An“important co-benefit” would be fewer heat-related fatalities. Crank up the cooling.
For years, environmental organizations and trial attorneys have pursued climate change lawsuits seeking enormous damages from oil and gas companies.
Following the DAPL protests, a North Dakota jury found Greenpeace liable for facilitating a coordinated and unlawful campaign against Energy Transfer – the company behind the pipeline – and the court entered a judgment of approximately $345 million.
National security is built on infrastructure long before it is tested on the battlefield. Tanks, aircraft, and troops cannot operate without fuel, electricity, and the industrial capacity behind them. Neither can the American economy. The pipelines, refineries, storage facilities, and export terminals that form the backbone of America’s energy network are therefore more than commercial assets. They are part of the nation’s strategic foundation.
Today, however, that foundation is under growing pressure from lawfare.
For years, environmental organizations and trial attorneys have pursued climate change lawsuits seeking enormous damages from oil and gas companies. The broader campaign is not simply about recovering compensation. Activists supporting it
Now, the legal fallout from the Dakota Access Pipeline (DAPL) protests appears to be opening a related but distinct front. This one could weaken accountability for illegal efforts to disrupt American energy projects and compound the uncertainty surrounding long-term infrastructure investment.
Following the DAPL protests, a North Dakota jury found Greenpeace liable for facilitating a coordinated and unlawful campaign against Energy Transfer – the company behind the pipeline – and the court entered a judgment of approximately $345 million. Yet a countersuit the organization has filed in the Netherlands challenges the American litigation that produced that verdict and seeks relief that could blunt its consequences. What happens now could affect how effectively the U.S. can protect critical energy infrastructure from unlawful interference.
If Greenpeace succeeds in using a foreign court to dilute accountability imposed by the American legal system, other activist organizations may conclude that they can disrupt energy projects without impunity. It would be as simple as seeking relief abroad when impacted parties try to hold them to account. That would embolden the tactics that make infrastructure harder and more expensive to build and undermine energy security.
Developers would face greater construction delays and security costs. Investors and insurers would price in the added risk. Legal uncertainty would leave America with less capacity and resilience when demand rises or a crisis strikes. This would not only affect economic security but embolden our adversaries to use energy as an instrument of coercion.
This should concern Europe as much as the U.S.
Russia offered the clearest recent warning after invading Ukraine, when it weaponized gas supplies and deliberately disrupted flows. The resulting shock sent European energy prices to unprecedented levels and exposed how dependence on an adversary for energy can constrain nations in a crisis. American LNG gave Europe an alternative: the continent received 68% of U.S. LNG exports in 2025 as it continued reducing its dependence on Russian energy. This experience demonstrated that energy security depends on reliable suppliers and the infrastructure needed to deliver their resources.
The broader American energy network that helped protect Europe from Russian coercion also strengthens NATO’s ability to endure a prolonged crisis. During my service as deputy commander of V Corps in Europe, I saw firsthand how reliable energy is a critical component of collective security. Given that a court in the Netherlands, a founding member of the Alliance, would consider a ruling creating a self-inflicted vulnerability on both sides of the Atlantic, it is clear that European nation energy policies and actions need to consistently reinforce the need for collective energy security.
The Dutch court should therefore reject any claim that would contradict matters decided in North Dakota or impose offsetting liability for Energy Transfer’s successful case. European policymakers should ensure that protections for public participation do not become tools for undermining accountability imposed by an allied nation’s courts.
American officials must also treat this as more than a dispute between private parties. The administration should use appropriate diplomatic and legal channels to defend American judgments and make the resilience of U.S. energy infrastructure part of the transatlantic security conversation.
The lesson from Europe is that a nation unable to secure dependable energy becomes vulnerable to those that control it. The vast energy supplies and robust network of energy infrastructure the U.S. possesses allows the country and its allies the freedom to withstand coercion and respond in a crisis. Energy security is national security, and America must preserve the legal certainty required to build and defend the infrastructure on which both depend.
Ret. Major General Bob Dees has more than 30 years of military leadership, including senior command roles in Europe. Dees brings firsthand expertise on the critical links between energy security, infrastructure resilience, and military readiness.
ropical land temperature proxies, essentially an “ancient jungle thermometer”, can be used to constrain global cooling during the Last Glacial Maximum (LGM, ~20,000–21,000 years ago), as shown in the 2026 study by Hou et al. published in Geophysical Research Letters.
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A recent 2026 study in Geophysical Research Letters (Hou et al.) estimates that global mean surface temperature during the Last Glacial Maximum (LGM, ~20,000- 21,000 years ago) was about 5.4°C colder than today, based on tropical land cooling constraints combined with climate model relationships.
Researchers compiled a multiproxy dataset of 61 tropical/subtropical (low- to mid-latitude) land temperature records from pollen assemblages, noble gases in ancient groundwater, glacial evidence (e.g., equilibrium line altitudes), and other proxies.
They estimated tropical land cooling of roughly 4.2°C relative to the present.
Using emergent relationships from 13 state-of-the-art LGM climate model simulations (linking tropical land temperatures, tropical sea-surface temperatures, and global mean temperature), they inferred tropical ocean cooling of about 2.6°C and the global figure of ~5.4°C.
A closely related preprint by the same group reported somewhat stronger cooling (tropical land −4.8°C with 95% CI −5.6 to −4.0°C; tropical SST −2.9°C; global mean −5.9°C with 95% CI −7.3 to −4.7°C), suggesting the published numbers reflect refinements.
Many earlier reconstructions (including those relying heavily on the MARGOsea-surface temperature compilation) suggested milder global cooling, often in the ~4- 5°C range or less for the tropics.
Stronger cooling estimates exist: Wikipedia notes ~6°C global average; a 2020 data-assimilation study (Tierney et al.) found −6.1°C (95% CI −6.5 to −5.7°C); noble-gas groundwater studies indicate low-to-mid-latitude land cooling of ~5.8°C (±0.6°C).
Tropical cooling has long been debated. Older CLIMAP reconstructions suggested limited tropical ocean cooling, but land proxies (pollen shifts, snowlines, noble gases from sites like Brazil) and some ocean proxies have repeatedly indicated larger changes (~5°C or more on tropical land in places).
The new work places the LGM toward the colder end of published ranges.
Because LGM CO₂ was much lower (~180- 200 ppm vs. pre-industrial ~280 ppm), a larger temperature drop implies higher equilibrium climate sensitivity (warming per CO₂ doubling).
The results make very low sensitivity (ECS ≲ ~3°C) less likely and help constrain models that underproduce glacial cooling.
Uncertainties remain: proxy scatter, dating precision, local effects, and the fact that the global number is inferred via model relationships rather than directly observed everywhere.
The approach is presented as adaptable to other periods or variables. Overall, it reinforces that the tropics experienced substantial cooling during the LGM peak and that the global climate system responded strongly to the lower greenhouse- gas levels and expanded ice sheets of that time.
Tropical land temperature proxies, essentially an “ancient jungle thermometer”, can be used to constrain global cooling during the Last Glacial Maximum (LGM, ~20,000–21,000 years ago), as shown in the 2026 study by Hou et al. published in Geophysical Research Letters.
Tropical regions (roughly 30°S–30°N) preserve a variety of climate proxies that record past land temperatures:
Pollen and vegetation assemblages (shifts in plant communities that track temperature and moisture).
Noble gases dissolved in ancient groundwater.
Glacial evidence such as equilibrium-line altitudes of tropical mountain glaciers.
Other indicators (e.g., certain geochemical or fossil records).
These provide relatively direct estimates of how much cooler tropical land surfaces were during the LGM compared with today. Because the tropics cover a large fraction of Earth’s surface and respond more uniformly than high-latitude regions dominated by ice sheets, they offer a useful anchor for global temperature reconstructions.
The researchers compiled a multiproxy dataset of tropical land temperature reconstructions and combined it with an ensemble of climate model simulations of the LGM. Within those models they identified stable statistical (“emergent”) relationships connecting:
Tropical land temperature change,
Tropical sea-surface temperature change, and
Global mean surface temperature change.
They then applied the observed tropical land cooling to these relationships. Results from the study (and its preprint) indicate:
Tropical land cooled by roughly 4.2–4.8 °C,
Tropical oceans cooled by about 2.6–2.9 °C,
Global mean surface temperature was approximately 5.4–5.9 °C colder than today.
These figures place the LGM toward the colder end of recent estimates and are colder than many reconstructions that relied heavily on earlier sea-surface temperature compilations such as MARGO.
A larger LGM temperature drop under substantially lower atmospheric CO₂ implies a more sensitive climate system (higher equilibrium climate sensitivity).
The tropical “thermometer” therefore helps tighten constraints on how strongly Earth’s climate responds to greenhouse-gas changes, while also offering a transferable method that can be applied to other time periods once sufficient proxy data exist.
An ancient tropical land- temperature record can serve as a practical thermometer that, when combined with model relationships, reveals the scale of the global chill during the peak of the last Ice Age.
MARGO stands for Multiproxy Approach for the Reconstruction of the Glacial Ocean Surface. It is a major international collaborative project (supported by IMAGES and PAGES) that produced one of the most influential reconstructions of sea- surface temperatures (SSTs) during the Last Glacial Maximum (LGM).
The primary synthesis was published in 2009 by the MARGO Project Members (led by C. Waelbroeck and colleagues) in Nature Geoscience: “Constraints on the magnitude and patterns of ocean cooling at the Last Glacial Maximum” (doi:10.1038/ngeo411).
Time interval: Strictly defined as 23–19 thousand years before present (following the EPILOG definition), narrower and more rigorous than the broader window used by the earlier CLIMAP project.
Proxies used (multiproxy philosophy):
Microfossil assemblage transfer functions (planktonic foraminifera, diatoms, dinoflagellate cysts, radiolarians).
Geochemical proxies (alkenone unsaturation index U^k_{37} and Mg/Ca ratios in planktonic foraminifera).
Data volume: Approximately 696 individual SST reconstructions from sediment cores worldwide.
Proxies used (multiproxy philosophy):
Microfossil assemblage transfer functions (planktonic foraminifera, diatoms, dinoflagellate cysts, radiolarians).
Geochemical proxies (alkenone unsaturation index U^k_{37} and Mg/Ca ratios in planktonic foraminifera).
The project emphasized that no single proxy is superior; combining them with quality assessments produces a more robust picture. Data were calibrated against a common modern temperature dataset and quality- controlled, with reliability flags assigned to individual records.
MARGO revealed stronger and more structured cooling than many earlier views:
Strongest annual-mean cooling (up to −10°C) occurred in the mid-latitude North Atlantic, with a steep temperature gradient between ~45°N and 60°N.
Cooling was more pronounced in the eastern than the western North Atlantic (contrasting with some CLIMAP patterns).
Tropical oceans (30°S–30°N) showed heterogeneous cooling, generally larger and more extensive than in CLIMAP, with greater cooling in the tropical Atlantic than in the Indian or Pacific. Western Pacific Warm Pool cooling was modest (roughly 1–3°C).
Large longitudinal (east–west) SST gradients existed in all major ocean basins—features not well captured by the climate models available at the time.
Some limited regions showed relative warmth or minimal cooling (e.g., parts of the northwest Australian margin), attributed to changes in ocean circulation.
Basin- averaged annual-mean cooling estimates (from the multiproxy dataset) were on the order of roughly −1.5 to −2.5°C depending on the ocean, with substantial spatial variability and uncertainty. Global tropical cooling was relatively modest compared with some later land-based or data- assimilation reconstructions.
Comparison with CLIMAP and Later Work
vs. CLIMAP (1970s–1980s): MARGO improved temporal definition, data density (especially in the North Atlantic and tropics), multiproxy integration, and quality control. It showed more heterogeneous tropical cooling and different longitudinal patterns.
Influence and limitations: MARGO became a standard benchmark for evaluating paleoclimate models (e.g., PMIP) and for estimating climate sensitivity. However, its relatively modest tropical and global-mean cooling has been criticized or revised by later work. Some studies argue it underestimates cooling in certain regions due to proxy limitations, calibration issues, or sparse coverage (especially in the Pacific and Southern Ocean). Newer compilations (e.g., TEA20) and data-assimilation products that blend proxies with models often indicate stronger overall LGM cooling (global SST anomalies closer to −3°C or more in some reconstructions).
The MARGO dataset (including gridded products on a 5° × 5° grid, individual site data, and reliability assessments) is publicly archived at:
NOAA/NCEI World Data Service for Paleoclimatology.
PANGAEA.
It remains widely used as a foundational reference, even as researchers develop updated multiproxy compilations and model- data fusion approaches that incorporate additional proxies and address spatial gaps.
In the broader context of LGM climate research and equilibrium climate sensitivity debates, MARGO’s relatively mild tropical cooling has historically supported lower- to- moderate sensitivity estimates.
More recent reconstructions that find stronger tropical and global cooling (including some land- proxy and emergent- constraint studies) tend to favor higher sensitivity values once pattern effects and other forcings are accounted for.
“Reassessing Last Glacial Maximum Cooling With Proxy-Constrained Emergent Relationships”
The study addresses the challenge of reconstructing global temperatures from sparse, unevenly distributed paleoclimate proxy data. It applies an emergent constraint framework:
Researchers assembled a new multiproxy dataset of tropical land temperature reconstructions for the Last Glacial Maximum (LGM, roughly 20-21 ka).
They identified robust statistical (“emergent”) relationships in an ensemble of paleoclimate model simulations linking tropical land temperature change, tropical sea- surface temperature (SST) change, and global mean surface temperature change.
Proxy- based tropical land cooling was then used to constrain the harder- to-observe tropical SST and global mean values.
From the preprint abstract:
Tropical terrestrial (land) temperature change: −4.8°C (95% CI: −5.6 to −4.0°C).
Constrained tropical SST change: −2.9°C (95% CI: −3.6 to −2.3°C).
Constrained global mean surface temperature change: −5.9°C (95% CI: −7.3 to −4.7°C).
A contemporaneous news summary of the published paper reported slightly milder central values (tropical land ≈ −4.2°C, tropical oceans ≈ −2.6°C, global ≈ −5.4°C), still pointing to relatively strong LGM cooling.
These estimates indicate a colder LGM climate than reconstructions that rely heavily on the MARGO SST compilation (which generally suggested milder tropical ocean cooling).
Broader Implications
The results support stronger glacial cooling, consistent with some independent lines of evidence (e.g., noble- gas groundwater studies showing substantial low-latitude land cooling).
Stronger LGM cooling (under substantially lower CO₂ concentrations) tends to favor higher equilibrium climate sensitivity (ECS) and makes very low ECS values less plausible.
The authors emphasize that the emergent- constraint approach is flexible and can be adapted to other time periods or climate variables once sufficient proxy data and model ensembles are available.
The paper uses tropical land proxies plus model- derived relationships to argue for relatively large LGM cooling (centered around 5.4- 5.9°C globally), placing the LGM toward the colder end of recent estimates and providing a transferable methodological framework for paleoclimate reconstruction.
Authors: Alicia Hou and colleagues (Thibaut Caley, Thomas Extier, Manuel Chevalier, Mathilde Brugère, Didier Swingedouw, Masa Kageyama, and Pascale Braconnot)
Abstract
Reconstructing global temperatures from sparse proxy data remains a key uncertainty in paleoclimate science. Here, we apply an emergent constraint framework that combines statistical relationships from paleoclimate model simulations with proxy-based estimates to infer unknown climate variables. We compiled a new multiproxy data set of tropical land temperature reconstructions for the Last Glacial Maximum (LGM), which implies tropical terrestrial cooling of −4.2°C (−5.0 to −3.5°C, 95% Confidence Interval, CI). Applying our emergent constraint framework to this terrestrial temperature reconstruction, we derived updated estimates of tropical sea surface temperature (−2.6°C; −3.3 to −2.0°C, 95% CI) and global mean surface temperature (−5.4°C; −6.5 to −4.4°C, 95% CI). These observation-based estimates support LGM cooling toward the colder end of published ranges, implying that very low equilibrium climate sensitivity (ECS < ∼3°C) is unlikely. Our method is adaptable for different time periods and climate variables, providing a flexible framework for integrating proxy and model information.
The boss of British Gas’s owner has warned the UK faces fuel shortages this winter as stockpiles fall to just 30% owing to an over-reliance on imports.
The boss of British Gas’s owner has warned the UK faces fuel shortages this winter as stockpiles fall to just 30% owing to an over-reliance on imports. The Telegraph has more.
Chris O’Shea, the Chief Executive of Centrica, said Britain had “almost no gas in storage in the UK for the coming winter”.
O’Shea said low gas reserves in the UK were a “huge concern” and that the country had “for too long” relied on other countries for energy imports while underinvesting in storage and power plants.
Britain’s gas facilities were around 30% full this week, down from 46% at the same time last year. They were more than 90% full in the two years before that.
Gas levels are currently at the lowest level for August since records began, according to Bloomberg data.
It follows the dramatic fall in tanker traffic through the Strait of Hormuz during the Iran war, which usually accounts for a fifth of the world’s oil and gas shipping.
O’Shea wrote on LinkedIn: “We have almost no gas in storage in the UK for the coming winter, and this is a huge concern as energy security is national security.”
European gas prices have doubled since the start of the Iran war.
Dutch TTF, the European gas benchmark, rose to more than €69 per megawatt hour on Tuesday, its highest level since March.
The jump in gas prices comes just a day after Ofgem increased its cap on energy prices by 4%, putting average household gas and electricity bills at £1,723 a year.
“The fatal conceit of ‘experts’ and ‘planners’ is promoting coercive social policy based on incomplete or wrong knowledge that the perpetrator thinks is God-like given and true. Ingmar Rentzhog is a danger, not prophet, in this regard.”
The Swedish website We Don’t Have Time declares itself to be “The World’s Largest Media Platform for Climate Action.” It is added: “We are democratizing knowledge about climate solutions to inspire and mobilize global action toward a prosperous, fossil-free future.”
A “prosperous, fossil-free future”? What is this group about? Start with the CEO and founder, Ingmar Rentzhog, who recently posted a sad plea, “The Biggest Lie Ever Told Is Only Four Words Long (August 20, 2026).
After ten years, he began, “I mostly feel exhausted.”
I have spent ten years inside the climate crisis, more or less around the clock. My two youngest children have never really known a father whose work was anything else. Ten years of broadcasts, climate weeks and COPs across continents. Ten years of being away, working late, raising money and fighting to keep this work alive.
After ten years, I thought I would feel that we had accomplished something. That all those years, all that work, all that sacrifice had moved us somewhere.
Ingmar Rentzhog’s pity party is a testament to a false cause and predictable fail. Consumers want the best energies. Most people want to make their own decisions and not be subject to ‘experts’ and government planners. “Don’t tread on me” means voluntary transactions between consenting adults, with government neutral. This is the moral high ground versus government intervention, which is all about coercion.
The big lie, Rentzhog insists, is that “we have more time.” But 83 million deaths from climate change [by 2100] hang in the balance–a Nature Communications study said so. (Remember John Holdren’s one billion possible deaths by 2020?) Rentzhog struggles with this knowledge.
That is the part I still struggle to carry home. How do I spend all day talking about progress, then look at my own children and explain that we are still not doing enough, and that they may end up paying an unbearable price because we kept telling ourselves there was still time?
So I do what most parents do. I ask about school. We eat dinner. We talk about ordinary things. And for a few hours, I try to live as though these were ordinary times.
Poor fellow. Perhaps a case can be made for others at the dinner table to stage an intervention to get Dad out of the climate cult. “A harder life, or the risk of no livable life at all” sure makes for bad company and a life at the margins.
Ingmar Rentzhog knows what the rest of us do not see.
Every parent knows the instinct to say “everything will be okay.” It is love, and it is exactly the instinct this lie exploits…. the hardest thing I have learned in ten years: it is not sustained mainly by greed. It is sustained by decent people who need it, because the truth feels unsayable to the people they love.
Megalomania? The fatal conceit of ‘experts’ and ‘planners’ is promoting coercive social policy based on incomplete or wrong knowledge that the perpetrator thinks is God-like given and true. Ingmar Rentzhog is a danger, not prophet, in this regard.
Betsy Rosenberg, a climate alarmist engaged with me on social media, sent me Rentzhog’s article. It was supposed to wake me up to the climate crisis. Instead, I responded:
The article is a tissue of errant analysis. “We Don’t Have Time turns ten,” is old, tired exaggeration. Climate alarmism has been predicted and falsified time and again. This is a reason why the public is not moved by the climate extremists (here).
Other fallacies, such as “ExxonKnew,” are easily rebutted [here]. The tobacco analogy? James Hansen, the father of the alarm, stated: “Let’s be clear: the frequent comparison of the fossil fuel and tobacco industries is nonsense. Fossil fuels are a valuable energy source that has done yeomen service for humankind.”
Regarding the way forward, with mitigation having failed over many decades, it is time for a total reset with government demoted and the masses promoted. Freedom, not climate statism.
The Dutch Ministry of Defense has published its Energy Security Roadmap, a national strategy to ensure that its armed forces have reliable energy supplies. While produced by a single NATO member, the document reflects a broader reality: Energy security is inseparable from military power.
The Dutch Ministry of Defense has published its Energy Security Roadmap, a national strategy to ensure that its armed forces have reliable energy supplies. While produced by a single NATO member, the document reflects a broader reality: Energy security is inseparable from military power.
The “roadmap” defines energy security as the continuous availability of reliable and affordable energy for both peacetime activities and military operations. It explicitly references NATO’s “single fuel policy,” which standardizes military logistics around liquid fossil fuels, particularly kerosene, to guarantee interoperability between allied forces. Currently, more than 95% of Dutch military aircraft, ships, and vehicles are powered by hydrocarbons.
Nonetheless, the European Union’s (EU’s) decarbonization proponents continue to demonize fossil fuels and advance wind and solar technologies that account globally for slightly more than 3% of energy supplies after two decades of subsidies. Even the Dutch document pays homage to EU decarbonization, but the need for liquid hydrocarbons will not be satisfied by climate rhetoric.
The bottom line for U.S. policymakers is that EU energy policy must be considered in assessing the continent’s defense capability.
The significance of the Dutch security document extends beyond military logistics. It is a wakeup call that energy is not simply an environmental or economic issue. It is fundamentally an issue of national security. Armed forces, industrial production, transportation networks, and critical infrastructure all depend on abundant and reliable energy. Without it, military readiness, economic strength, and national autonomy decline.
Throughout history, energy has been the foundation of state power. Nations with secure access to affordable energy possess stronger economies, greater military capabilities, and more freedom of action. Nations dependent on external suppliers expose themselves to coercion and worse.
Global energy trends reinforce these facts. According to the 2026 Statistical Review of World Energy, 86% of global primary energy consumption was fed by fossil fuels. Despite growth in renewable technologies, the world remains overwhelmingly reliant on oil, natural gas, and coal. Many major powers are adapting to this reality, as the Brussels bureaucracy seems to ignore it.
China, for example, is expanding renewable generation while simultaneously building new coal capacity and securing control over supply chains for strategic minerals. This strategy prioritizes energy availability and resilience as foundations of national power. China is strengthening both its economic position and its long-term security.
This intersection of energy policy with defense capability may be an existential crack in the EU’s “green” facade. The European Union remains heavily dependent on imported energy and critical raw materials, while many industries face significantly higher energy costs than competitors in the United States and Asia. Rising costs have contributed to pressures on steel, chemicals, and manufacturing, industries that form the backbone of a nation’s defense.
Armies require fuel, but they also need steel, chemicals, machinery, shipbuilding capacity, electronics, and advanced manufacturing. A nation that struggles to sustain competitive industrial production will have difficulty producing tanks, munitions, drones, aircraft, and warships at the scale required in a crisis.
As the EU has demonized fossil fuels in the name of climate policy, industrial electricity prices have risen to about twice U.S. levels and about 50% above China’s. Last year, steel output fell to its lowest level since 1960. ThyssenKrupp is cutting 11,000 jobs from its steel division, and that is just one example. This deindustrialization is incompatible with a robust defenseand sovereignty.
NATO’s military capabilities depend not only on budgets and troop numbers but also on the energy supplies and industrial foundation that support them. The Dutch strategy implicitly recognizes that operational readiness begins with energy security.
The United States has reinforced its strategic position through abundant domestic oil and gas production, which supports both economic growth and projection of military power. Meanwhile, Europe refuses to take full advantage of domestic energy reserves, clinging to economically destructive policies that can only undermine the security of the West.
The lesson of the Dutch Energy Security Roadmap is that energy security is a prerequisite of national security. An alliance that seeks to deter adversaries and maintain sovereignty cannot afford to overlook that connection.
Dr. Samuel Furfari has been teaching energy geopolitics since 2003 and served as an official at the Directorate-General for Energy of the European Commission for 36 years. He is the author of more than 20 books on energy policy and geopolitics.
This commentary was first published at Daily Signal August 26.
Saharan dust outbreaks over Europe are a well- documented, recurring meteorological process driven by wind patterns that lift mineral particles from North African deserts and transport them across the Mediterranean.
It is a natural weather phenomenon.
Saharan dust fertilization is a major natural biogeochemical process.
AI generated by Grok
Saharan dust outbreaks over Europe are a well- documented, recurring meteorological process driven by wind patterns that lift mineral particles from North African deserts and transport them across the Mediterranean.
There is no credible evidence linking the current or typical events to deliberate “massive atmospheric interventions,” geoengineering, or related conspiracy claims.
It is a natural weather phenomenon.
Weather services, satellite imagery (including NASA), and models from sources such as Copernicus and national meteorological agencies describe a large plume of Saharan dust being carried northward by southerly/southwesterly winds associated with an African high- pressure system and related atmospheric circulation.
This has produced yellowish/milky skies, reduced visibility, elevated PM10 levels, and in some places “muddy rain” across parts of Italy (including Sicily and Sardinia), Spain, France (Corsica, Alpes-Maritimes, southern Alps), and neighboring areas.
Concentrations were particularly noticeable around 27- 28 August 2026, coinciding with a heatwave that also brought very high temperatures (locally >40 °C in southern Italy and the islands). Forecasts indicated gradual reduction of the dust load afterward.
These descriptions match standard forecasting language used by services such as Windy and national agencies; the plumes are visible on satellite and modeled aerosol products because they are real mineral dust, not something introduced artificially.
How the natural process works:
Strong surface winds or convective activity over arid Saharan/Sahel source regions (e.g., via low-level jets, cold pools, or synoptic systems) lift fine mineral particles.
Once aloft, the dust is carried in layers (sometimes as a Saharan Air Layer) by large-scale winds. In the Mediterranean sector this often involves southerly flow linked to high pressure over North Africa or troughs that draw African air northward.
The dust can travel hundreds to thousands of kilometers, producing hazy/yellowish skies, depositing reddish- brown residue when mixed with rain, and temporarily raising particulate levels. It is most common in spring but occurs in other seasons, including summer under the right patterns.
This has been observed and studied for decades (and longer in historical records). Models, lidars, photometers, in-situ sampling, and satellites routinely track it.
Recent studies (including analyses of monitoring data from ~2012- 2021) indicate increases of roughly 10- 25% in desert dust concentrations over parts of Europe, with higher averages in the south.
Drivers discussed in the literature include shifts in atmospheric circulation that more frequently draw African air masses northward and increased aridity/desertification in source regions, both influenced by climate change.
These are natural emissions whose transport and intensity can be modulated by a warming climate; they are not evidence of intentional large- scale spraying.
The same dust can affect air quality, health (especially for sensitive groups), visibility, solar irradiance, and even Alpine snowmelt when it settles.
Assertions that these events result from deliberate geoengineering, “chemtrails,” or intentional release of toxic materials have been repeatedly examined and rejected by atmospheric scientists, meteorological services.
Saharan dust naturally contains iron oxides (including hematite, which contributes to color and weak magnetism) and other minerals from the desert surface; laboratory analyses of residues match this mineralogical profile rather than industrial spraying.
Contrails (water- vapor trails from aircraft) are distinct and unrelated.
There is no verified mechanism or evidence that “massive atmospheric interventions” are producing the observed plumes, which align with wind fields, satellite aerosol optical depth, and dust- transport models.
The yellowish skies and dust currently noted over parts of Europe are the expected result of a classic Saharan dust outbreak under the prevailing weather pattern.
Frequency and intensity can vary with climate and circulation changes, but the phenomenon itself is natural and long- established.
The Saharan Air Layer (SAL) is a well- defined, elevated mass of warm, dry, and dusty air that originates over the Sahara Desert and is frequently transported westward over the tropical North Atlantic Ocean (and sometimes northward toward the Mediterranean and Europe).
It typically forms in late spring through early fall, peaks from mid- June to mid- August, and occurs in outbreaks every 3- 5 days.
Strong surface heating over the Sahara creates a deep, well- mixed boundary layer of hot, dry air laden with mineral dust.
As this air moves westward over the cooler, moister marine boundary layer of the Atlantic, it becomes elevated (base typically ~1-1.5 km, ~850- 900 hPa, top often 3-5+ km, ~500- 550 hPa near the African coast, with the base rising and top descending farther west).
Thickness is commonly 2- 2.5 miles (~3- 4 km). It is associated with the mid- level African Easterly Jet (AEJ; strong easterly winds of 25- 55 mph / 10- 25 m/s, often at 2- 4.5 km altitude). Dust loads can be substantial (tens of millions of tons transported annually), and relative humidity is often ~50% lower than typical tropical air.
Satellite observations (visible, infrared, water vapor channels), lidars, radiosondes, and models routinely track it due to its distinct temperature, humidity, wind, and aerosol signatures.
Primary Effects
1. Suppression of tropical cyclone (hurricane) formation and intensification (most studied impact) The SAL acts as a natural inhibitor in the Atlantic main development region, especially early in the season (June–July). Key mechanisms form a “trifecta”:
Extreme dryness — Promotes evaporative cooling and downdrafts that disrupt convection and the storm’s heat engine. Clouds encountering this dry air often collapse.
Enhanced vertical wind shear — The AEJ increases shear, tilting the vortex and misaligning thunderstorms (analogous to tipping a skateboarder).
Warmth and stability — Dust absorbs solar radiation, maintaining warmth aloft and creating a temperature inversion (stronger convective inhibition, ~40% higher on average). This acts like a “lid,” limiting upward motion. Dust can also slightly cool sea surface temperatures by reducing insolation.
Effects are generally stronger on weaker systems (tropical depressions/storms) than mature hurricanes. Some studies note nuanced or context- dependent roles (e.g., possible early-stage enhancement in certain positions relative to the storm, or variable impacts on cloud microphysics), but the dominant consensus from NOAA and observational work is suppression. SAL activity often declines by late August and early September, coinciding with the peak of the Atlantic hurricane season.
2. Radiative and thermodynamic effects Mineral dust scatters and absorbs shortwave (solar) radiation while interacting with longwave (infrared). Typical impacts include:
Surface cooling (shortwave reduction of tens of W/m², e.g., up to –40 W/m² in strong cases; atmospheric warming within the layer).
Net heating rates inside the dust layer often positive (shortwave heating of +0.3 to several K/day near concentration peaks, modulated by longwave cooling). Enhanced water vapor sometimes present in the upper SAL can dominate heating rate calculations and shift peaks.
Stabilization of the layer and reduced mixing below; possible influences on the marine boundary layer and ITCZ convection (weakening/southward shift in some cases).
Broader climate effects: cooling of the ocean surface, potential feedbacks on circulation. acp.copernicus.org
3. Air quality, health, and visibility Dust (PM10 and finer fractions) degrades air quality, reduces visibility (sometimes to tens of meters in intense “calima” events over the Canary Islands or elsewhere), and produces hazy skies with vivid orange, red sunrises and sunsets. Health impacts include respiratory irritation, exacerbated asthma/COPD, and increased hospital admissions in downwind regions (Caribbean, southeastern U.S., Mediterranean, Europe). Fine particles can penetrate deep into lungs.
Clouds and precipitation — Can serve as cloud condensation/ice nuclei (microphysical effects); overall tendency toward suppression of low-level convection in affected areas.
Aviation and surface activities — Reduced visibility can disrupt flights and transport.
Regional weather — Contributes to hazy conditions and can interact with local systems over the Mediterranean/Europe when plumes move northward (as in recent European dust events).
Longer- term or large-scale: Links to Sahel rainfall variability, North Atlantic Oscillation-like patterns, and climate trends (e.g., historical increases in dust linked to drought periods).
SAL intensity and westward extent vary with source- region emissions (tied to drought, winds, and land conditions), synoptic patterns (tropical waves, high pressure), and climate factors.
It is a natural phenomenon first characterized in the early 1970s, continuously monitored by NOAA and others because of its importance to tropical meteorology. While dust transport to Europe is related (via similar Saharan sources and winds), the classic “SAL” designation emphasizes the elevated Atlantic structure and its tropical cyclone interactions.
The SAL’s dominant, well- established effects are thermodynamic and dynamic suppression of Atlantic tropical cyclones via dryness, shear, and stability, combined with radiative cooling at the surface, atmospheric heating within the layer, and downwind air- quality degradation.
Research continues on microphysical nuances and climate feedbacks, but the core impacts are robustly supported by satellite, aircraft, and modeling evidence.
Mineral dust (primarily from deserts such as the Sahara, which accounts for roughly half of global atmospheric dust) is one of the most abundant aerosols by mass and exerts complex, multi-faceted effects on Earth’s climate system. These include direct radiative interactions, indirect effects on clouds, biogeochemical feedback, and influences on the cryosphere and atmospheric circulation.
Dust scatters and absorbs shortwave (solar) radiation while absorbing and emitting longwave (infrared/thermal) radiation:
Shortwave (SW): Generally produces a cooling effect at the top of the atmosphere (TOA) by reflecting sunlight back to space and reducing surface insolation. Central estimates of the SW direct radiative effect (DRE) are around −0.40 W m⁻² (range roughly −0.10 to −0.70 W m⁻²). Surface cooling can be stronger regionally (e.g., tens of W m⁻² during intense Saharan outbreaks).
Longwave (LW): Produces a warming effect by trapping outgoing terrestrial radiation (similar to a greenhouse gas). Observationally constrained estimates are about +0.25 ± 0.06 W m⁻², higher than many climate models that underrepresent coarse dust and LW scattering.
Net direct effect: Often near-neutral to weakly cooling (e.g., −0.15 ± 0.35 W m⁻² or broader estimates of −0.2 ± 0.5 W m⁻² for the effective radiative effect including adjustments). The sign and magnitude remain uncertain due to mineralogy (especially iron oxides that control absorption), particle size distribution (fine vs. coarse/giant particles), and vertical distribution. Recent constraints from satellite mineralogy data (e.g., EMIT) have significantly reduced uncertainty in SW effects.
Dust warms the atmosphere within the dust layer (via absorption) while cooling the surface below, which can stabilize the atmosphere and alter local circulation.
Clouds: Dust acts as cloud condensation nuclei (CCN) and ice- nucleating particles, influencing cloud albedo, lifetime, and precipitation efficiency. Effects can either enhance or suppress precipitation depending on conditions; overall impacts are highly uncertain.
Cryosphere: Dust deposition darkens snow and ice (reducing albedo), accelerating melt, particularly important over glaciers, the Tibetan Plateau, and polar regions.
Atmospheric dynamics: Regional effects include influences on the West African monsoon, African Easterly Jet, Saharan Air Layer stability, and tropical cyclone activity (as discussed previously). Dust can also affect solar power generation by reducing irradiance.
Dust delivers iron, phosphorus, and other nutrients to the ocean and land:
Ocean iron fertilization stimulates phytoplankton growth in iron- limited regions, enhancing primary production and the biological carbon pump (export of organic carbon to the deep ocean). This contributes to atmospheric CO₂ drawdown.
Estimates indicate dust supports a few percent of global ocean export production, with higher regional importance (e.g., Southern Ocean, North Atlantic).
Historical and glacial- interglacial variations in dust flux are linked to significant CO₂ and climate changes. Asian (glaciogenic) dust often has higher bioavailability of ferrous iron than aged Saharan dust.
These effects create climate feedbacks: cooling from increased dust can reduce atmospheric CO₂ further via enhanced ocean uptake.
Global dust mass loading has increased by an estimated 55 ± 30% since pre- industrial times (driven largely by North African and Asian sources due to land- use change, desertification, and climate shifts). This has produced a small net cooling effective radiative forcing of about −0.07 ± 0.18 W m⁻², partially offsetting greenhouse gas warming. Many climate models underrepresent this historical increase.
Future projections are highly uncertain and diverge widely across models, depending on changes in aridity, winds, vegetation, and land use. Increased dust could enhance cooling and fertilization effects in some scenarios, while decreased dust in others could reduce them.
The best current assessment is that mineral dust exerts a net cooling influence on climate (effective radiative effect ≈ −0.2 ± 0.5 W m⁻²), though the large uncertainty range means a weak warming cannot be ruled out.
Key challenges include accurately representing particle size (especially super- coarse dust), mineral composition, optical properties, cloud interactions, and biogeochemical feedback in models.
Mineral dust is a critical climate agent that both responds to and influences climate change through radiative, cloud, and nutrient pathways. Its effects are strongest regionally near major sources (e.g., North Africa, Asia) but have global reach via long- range transport.
Saharan dust fertilization is a major natural biogeochemical process.
Mineral dust from the Sahara (Earth’s largest dust source) transports essential nutrients, primarily iron (Fe), plus phosphorus (P), and others, across the Atlantic and beyond.
This supports phytoplankton growth in nutrient- limited ocean regions and replenishes soils in ecosystems such as the Amazon rainforest. The process influences marine productivity, the carbon cycle, and climate feedback.
Dust is lifted by winds over arid Saharan/Sahel sources (notably the Bodélé Depression in Chad) and transported mainly westward via the Saharan Air Layer and trade winds.
Roughly hundreds of teragrams (Tg; 1 Tg = 1 million tons) of dust are emitted annually from North Africa, with a substantial fraction deposited in the Atlantic Ocean (estimates around 200–300 Tg yr⁻¹ into the Atlantic overall) and smaller amounts reaching the Americas.
Key nutrients include:
Iron: Critical micronutrient for photosynthesis, respiration, and nitrogen fixation. Much of the iron in fresh dust is not immediately bioavailable (locked in mineral forms). Atmospheric processing during long- range transport—photochemical reactions, acidic processing, cloud interactions—increases solubility and bioreactivity. Studies of seafloor sediments show that the farther dust travels, the higher the proportion of bioavailable iron (as reactive forms are preferentially consumed by organisms before reaching the seafloor). Solubility can rise from <1% near sources to several percent farther west.
Phosphorus and others: Important for terrestrial systems and can co- limit marine productivity or stimulate nitrogen- fixers.
Deposition occurs via dry settling or wet deposition (rain scavenging), which can enhance nutrient release (especially under acidic conditions).
In iron- limited regions (parts of the tropical/subtropical Atlantic, and more broadly high- nutrient low-chlorophyll zones), dust deposition stimulates phytoplankton.
Effects include:
Improved physiological health/photosynthetic efficiency of phytoplankton communities (especially in stable low- latitude waters).
Increased biomass in seasonally varying or higher-latitude areas.
Stimulation of nitrogen- fixing organisms (e.g., Trichodesmium), which can alleviate nitrogen limitation and boost overall productivity.
Blooms of heterotrophic bacteria such as Vibrio in response to iron pulses (observed increases of 5-30× within 24 hours in Caribbean/Atlantic surface waters).
Global estimates suggest atmospheric dust deposition supports ~255 Tg of carbon per year in primary production (about 4.5% of global annual export production), with regional contributions much higher (20-40% of exported particulate carbon flux in some areas).
In the Southern Ocean, dust- iron supports an estimated ~33% of annual net community production under modern conditions (higher, ~64%, during dustier glacial periods).
Dust also acts as ballast: mineral particles increase the sinking rates of organic matter, enhancing carbon export to the deep ocean.
Sediment- trap studies in the North Atlantic gyre show roughly twice the carbon fluxes (and higher export efficiency) compared with dust- poor South Atlantic regions, linked to both fertilization (including N- fixation) and mineral ballasting.
Saharan dust is a key phosphorus source for the Amazon. Amazonian soils are nutrient- poor; rainfall and flooding leach P, but annual dust inputs (estimates of ~20- 40 Tg dust, delivering ~22,000 tons of P) roughly balance these losses, sustaining rainforest productivity. Iron and other micronutrients also benefit canopy and soil microbes/plants. Similar (though smaller scale) nutrient inputs occur to Caribbean islands, Florida, and even European forests via northward transport.
By boosting primary production and carbon export, dust fertilization contributes to atmospheric CO₂ drawdown (the “biological pump”).
This is part of glacial- interglacial climate dynamics: higher dust fluxes during glacial periods enhanced Southern Ocean productivity and helped lower CO₂. Dust also has direct radiative effects (cooling) and can influence circulation, precipitation, and regional climate variability (e.g., equatorial Atlantic SST and rainfall patterns).
Uncertainties remain around exact bioavailability fractions, the relative roles of Fe vs. other nutrients, scavenging of dissolved iron by dust particles themselves, and responses under future climate (changing dust emissions due to aridity, land use, or circulation shifts). Models and observations continue to refine these estimates.
Saharan dust acts as a natural fertilizer linking desert source regions to distant marine and terrestrial ecosystems.
Its iron (increasingly bioavailable with transport distance) and phosphorus drive productivity, support food webs, and influence global carbon cycling- effects documented through satellite chlorophyll observations, sediment cores, shipboard experiments, sediment traps, and modeling.
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