Data from NASA satellites reveal that the Earth is reflecting less sunlight than it did two decades ago, with the Northern Hemisphere showing the most pronounced decline. Dr. Norman G. Loeb and colleagues at NASA’s Langley Research Center analyzed solar radiation, albedo, and radiation balance data from 2001 to 2025, concluding that both hemispheres have darkened and are absorbing more energy.
Overall, the planet’s radiation absorption has risen by 0.83 watts per square meter per decade, with the Northern Hemisphere accounting for 0.34 watts per square meter. Although ocean currents and atmospheric circulation offset some of this gain, a net increase of 0.21 watts per square meter per decade remains, indicating that previously assumed balance mechanisms are faltering.
Key contributors to reduced reflection include shrinking Arctic ice and snow, decreasing aerosols and clouds due to reduced pollution in major regions, and temporary increases in Southern Hemisphere reflection from bushfires and the Hunga Tonga volcanic eruption.
The implications are serious for global climate. More absorbed energy translates to long-term warming, particularly for Europe and North America. Scientists emphasize that these changing reflection patterns need to be considered in future climate modeling, as it remains uncertain whether natural mechanisms will restore equilibrium or if this asymmetry will continue to intensify.