Study Reveals Climate Warming Driven by Receding Cloud Cover – Watts Up With That?

Now let’s look at the broader scientific community catching up to Dr. Spencer.

Abstract

Recent Earth energy budget observations show an increase in the sunlight absorbed by the Earth of 0.45 W/m² per decade, caused primarily by a decrease in cloud reflection. Here we decompose the solar radiative budget trends into general circulation and cloud controlling process components. Regimes representing the midlatitude and tropical storm zones are defined, and the trends in the areal coverage of those regimes which are potentially induced by circulation changes are separated from trends in the cloud radiative effect within each regime which are potentially induced by changes in local cloud controlling processes. The regime area change component, which manifests itself as a contraction of the midlatitude and tropical storm regimes, constitutes the largest contribution to the solar absorption trend, causing decreased sunlight reflection of 0.37 W/m² per decade. This result provides a crucial missing piece in the puzzle of the 21st century increase of the Earth’s solar absorption.

Key Points

• Satellite observations show that in the past 24 years the worlds storm cloud zones have been contracting at a rate of 1.5%–3% per decade
• This contraction allows more solar radiation to reach the Earth’s surface and constitutes the largest contribution to the observed 21st century trend of increased solar absorption

Plain Language Summary

Analysis of satellite observations shows that in the past 24 years the Earth’s storm cloud zones in the tropics and the middle latitudes have been contracting at a rate of 1.5%–3% per decade. This cloud contraction, along with cloud cover decreases at low latitudes, allows more solar radiation to reach the Earth’s surface. When the contribution of all cloud changes is calculated, the storm cloud contraction is found to be the main contributor to the observed increase of the Earth’s solar absorption during the 21st century.

To understand the full implications of this study, we need to parse its findings in plain terms. The paper concludes that the Earth has absorbed significantly more solar radiation over the past 24 years—0.45 W/m² per decade. The primary culprit? A reduction in cloud cover, specifically a contraction of the midlatitude and tropical storm-cloud zones. This change has resulted in less solar radiation being reflected back into space and more being absorbed by the Earth’s surface. Crucially, 0.37 W/m² of this uptick is attributed solely to this contraction in cloud coverage, a result of large-scale atmospheric circulation changes:

“This cloud contraction, along with cloud cover decreases at low latitudes, allows more solar radiation to reach the Earth’s surface. When the contribution of all cloud changes is calculated, the storm cloud contraction is found to be the main contributor to the observed increase of the Earth’s solar absorption during the 21st century.”

Let’s pause there. Climate science has long emphasized the role of anthropogenic greenhouse gases—especially CO2—in trapping outgoing longwave radiation, contributing to surface warming. Yet here we have empirical satellite observations showing that changes in shortwave radiation absorption, due to cloud dynamics, dominate recent trends in Earth’s energy imbalance. That revelation alone should be enough to shake the very foundations of climate policy, which has funneled trillions into carbon control with scant attention paid to cloud feedback mechanisms.

More damning still is the admission that these changes are likely tied to “general circulation shifts,” specifically poleward movements of storm tracks and contractions of the Intertropical Convergence Zone (ITCZ). These are phenomena long suspected in model projections but never given such a central, quantifiable role in the planetary energy budget. And here’s the kicker: these circulation shifts are said to have emerged gradually, to the tune of 1.3% to 3% per decade:

“In all three zones, the area coverage of the L‐TCC regime shows statistically significant decreases with extremes of 1.84 ± 0.38% to 3.20 ± 0.97% per decade… indicating a contraction of the midlatitude storm regions and a narrowing of the ITCZ region.”

These aren’t theoretical projections—they are based on hard satellite data from the MODIS and CERES instruments. Models, by contrast, have only roughly hinted at these changes, and often fail to reproduce them with consistency.

The paper outlines that most of the shortwave cloud radiative effect (SWCRE) change—the key measure of how much solar energy is reflected by clouds—comes not from changes in cloud properties themselves, but from the shrinking geographic area of major cloud regimes:

“In all zones, the dominant trend is the SW cloud radiative warming that is coming from the contraction of the S‐SWCRE regimes and the corresponding expansion of the W‐SWCRE regimes.”

That’s the kind of subtle, high-leverage feedback mechanism that models tend to get wrong or underrepresent entirely. And that’s a problem. Because if your model can’t accurately simulate cloud regime shifts—which appear to contribute more than 80% of the increase in solar absorption—then your forecasts for future warming are at best incomplete, and at worst, wildly misleading.

Tselioudis et al. even admit this shortcoming, noting:

“It is imperative to test the skills of climate models in simulating the observed storm‐cloud area contraction, and to use both modeling and observational analyses to understand the interactions between atmospheric dynamics shifts and storm cloud changes.”

That’s bureaucratese for “we didn’t see this coming, and we’re not sure our models can catch up.” It’s reminiscent of NASA’s Gavin Schmidt’s recent handwringing over 2023’s “unexplainable” heat spike, suggesting that “we could be in uncharted territory.” Now, we have the chart. And it doesn’t point toward CO2 alone—it points to dynamic, cloud-driven changes that no carbon tax will stop.

What this paper also inadvertently confirms is the unreliability of using long-term climate models to dictate aggressive, disruptive policies like Net Zero. The models are missing key physical processes—cloud behavior, aerosol effects, and large-scale atmospheric shifts. As the paper notes:

“The general circulation shift component constitutes the dominant term of the recent increase in absorbed solar radiation and provides a crucial missing piece in the puzzle of the 21st century radiative warming and the large heat anomaly of 2023.”

Yet these shifts are only just beginning to be understood, and their driving forces—whether natural variability, solar activity, ocean cycles, or some interaction thereof—remain far from nailed down.

Worse still, the authors openly speculate that low-latitude cloud reductions could be driven by aerosol changes—particularly the decline in ship emissions:

“This component shows a significant cloud radiative warming of 0.21 W/m²/decade that can be attributed to aerosol indirect effects on clouds including effects from the reduction of aerosol ship emissions.”

That’s right: the same well-meaning efforts to reduce pollution from ocean-going vessels may have accelerated warming by allowing more sunlight to hit the surface. Climate mitigation whack-a-mole strikes again.

In sum, Tselioudis et al.’s paper is a quietly revolutionary work—not because it introduces a new alarmist narrative, but because it destabilizes the prevailing one. It shows that:

• Cloud feedbacks, especially those driven by circulation shifts, have enormous and previously underestimated impacts on Earth’s radiative balance.
• These changes are driven by complex, poorly understood dynamics that current climate models struggle to replicate.
• Policy decisions predicated on “settled science” have been made in the absence of understanding a major component of the Earth’s energy system.

If climate science were a functioning scientific discipline rather than a priesthood, this paper would trigger a major course correction. It would cast doubt on the simplistic link between CO2 and warming, redirecting focus toward cloud physics, ocean-atmosphere interactions, and circulation dynamics. It would foster humility in the face of atmospheric complexity—not arrogance born from model outputs.

But don’t expect that anytime soon. Instead, expect the usual suspects to spin this as evidence of “even worse than we thought” warming, conveniently omitting the part where their models didn’t predict it and their policies had nothing to do with it.

In the meantime, this paper should serve as ammunition for any skeptic pointing out the absurdity of building trillion-dollar policies on the backs of incomplete and overconfident simulations. The cloud regimes are shifting. The models aren’t keeping up. And neither is the narrative.