The Earth has become darker: it reflects less sunlight. NASA researchers led by Norman Loeb found that from 2001 to 2024, the Earth has become darker and reflects less sunlight, especially noticeable in the north. The reason is the melting of ice and snow cover and reductions in aerosol pollution. These changes do not equally affect the southern and northern hemispheres, as natural phenomena in the southern hemisphere partially compensate for these changes.
Research Findings
In the study published in the Proceedings of the National Academy of Sciences, it was noted that the darker Earth was identified more significantly in the northern hemisphere. Norman Loeb, the leader of the NASA team, emphasized the importance of this discovery for understanding the impact of surface and atmospheric processes on the planet's energy balance.
“We found a previously unknown imbalance between the hemispheres in the reflection of solar energy,” noted Loeb. “This important discovery helps us understand how surface and atmospheric processes influence the planet's energy balance.”
Changes in the Hemispheres
It was found that the difference in received solar radiation between the northern and southern hemispheres is explained by changes in the atmosphere, water vapor content, and clouds, as well as the albedo of the Earth's surfaces. These factors have led to an increase in the darkening of the northern hemisphere. Additionally, the interaction of radiation with aerosols affects the reflection of sunlight: a decrease in aerosol pollution in the northern hemisphere and an increase in the southern. Understanding these processes is crucial for improving climate models and predicting global warming.
NASA's research shows that the Earth is becoming darker and reflecting less sunlight, particularly in the northern hemisphere. The melting of ice cover and reduced aerosol pollution are the main reasons for these changes. The prospects for climate models and understanding global changes can be enhanced through this research.