For 24 years, NASA satellites have been observing the Earth from above, recording every variation in light that our planet sends back into space. Today, thanks to data from the CERES (Clouds and the Earth’s Radiant Energy System) program, scientists have discovered something disturbing: the Earth is getting darker.
And it’s not just an impression. The Earth’s albedo – that is, the amount of reflected solar energy – is visibly decreasing, and the phenomenon is much faster in the northern hemisphere:
Both hemispheres are darkening, but the northern one is doing so at a faster rate.
In practice, the North of the planet absorbs more and more solar radiation and sends less of it back into space. The result is a vicious cycle: more heat, more melting ice, less white surfaces that reflect light, and therefore even more heat.
What is happening to Earth
The Earth’s climate is based on a subtle balance, that between the light that arrives from the Sun and the heat that the Earth sends back. It is the so-called radiative balance: a sort of planetary “energy account” that decides how much the planet warms or cools.
Yet, something is going wrong. Measurements from CERES, which began in 1997, show that the atmosphere and oceans can no longer compensate for the differences between the two hemispheres.
In the northern hemisphere, in fact, the increase in solar absorption is evident:
Scientists speak openly of “limits in the ability of clouds to maintain symmetry between the two hemispheres”.
Simply put: Even clouds, which usually act as a natural filter, appear to have lost some of their effectiveness in redistributing the planet’s light and heat.
Added to this is another non-negligible fact: the northern hemisphere is warming and wetting more than the south, a sign of profound changes in global atmospheric circulation.
The Earth changing color: a bright wake-up call
The fact that the Earth is “darkening” is not just a laboratory curiosity: it is a direct signal of climate change. A planet that reflects less light is a planet that retains more energy, therefore more heat. And this, in the long term, accentuates the climate imbalance between north and south.
The authors of the study, published on PNAScall for caution: the observation period (24 years) is still too short to draw definitive conclusions. But the trend is clear: the world is becoming dimmer, and this dimming advances fastest where most humans live.
The planet isn’t just warming up — it’s also turning off the lights.
You might also be interested in:
