You might not notice it on a day-to-day basis, but over a course of decades, NASA scientists have discovered that the world is getting darker.

That’s according to a new study published in the journal PNAS, which shows there is also increasing disparity between the Northern and Southern Hemispheres.

And there are a complex set of reasons behind this change, which – surprise surprise – are in part due to the ever-worsening climate crisis.

The research team were able to reach their conclusions – that Earth is becoming darker – by observing over two decades worth of satellite-collected data from NASA’s Clouds and the Earth’s Radiant Energy System (CERES) project.

And the growing difference between the ways in which the Northern and Southern Hemispheres are absorbing solar radiation is increasingly stark, as the research team explain in their study:

“The general circulation of the atmosphere–ocean system is closely linked with the distribution of radiant energy within the climate system. On average, the southern hemisphere [SH] and northern hemisphere (NH) reflect the same amount of solar radiation, and the NH emits more outgoing longwave radiation. Using satellite observations, we find that while both hemispheres are darkening, the NH is darkening at a faster rate.”

There’s many, many reasons for this – weather and non-weather related – but all come down to the same conclusion, that the changes to the hemispheres are making them drastically different.

And it’s no secret that climate change is having a significant effect on each hemisphere’s albedo (the surface reflectivity, whether it reflects more or less solar radiation), and for the most part, human effects on the environment are to blame:

“The hemispheric difference in surface warming and surface albedo in response to increasing CO2 forcing seen in climate model simulations together with any further hemispheric changes in aerosol suggests we should see an increase in hemispheric albedo asymmetry in the future. However, if clouds compensate for hemispheric asymmetry (e.g., through circulation changes), but do so over a longer timescale, the trend in the NH–SH ASR difference may reach some upper limit.”

Why is this a problem? Well, it’s all a sign of the world’s atmospheric circulation changing, which is intensifying the heating effect on the Northern Hemisphere. And while clouds were thought to redistribute this heating and maintain some kind of equilibrium, according to the study, this does not seem to be the case.

Which is not a good sign for our planet, as it continues to heat further, to unhealthy and unsustainable rates.

If you thought that was interesting, you might like to read about the mysterious “pyramids” discovered in Antarctica. What are they?