New NASA research shows that the Earth is reflecting less sunlight into space, with the effect particularly pronounced in the Northern Hemisphere. A team led by Dr. Norman G. Loeb from NASA’s Langley Research Center analyzed 24 years of satellite data tracking solar radiation, albedo, and the Earth’s radiation balance. Their findings indicate that since 2001, both hemispheres have become darker, absorbing more energy overall.
Radiation absorption has increased by 0.83 watts per square meter per decade, with the Northern Hemisphere absorbing an extra 0.34 watts per square meter. While ocean and air currents partially offset this, a net gain of 0.21 watts per square meter per decade persists, signaling a growing imbalance in the planet’s energy system.
Several factors contribute to reduced reflection: Arctic ice and snow loss exposes darker surfaces, decreasing albedo; reduced air pollution in Europe, China, and the US means fewer aerosols, clouds, and reflected radiation; and while Southern Hemisphere bushfires and the Hunga Tonga eruption have temporarily boosted reflection, the long-term effect is minor.
The consequences are significant. Earth’s diminished reflectivity means more stored energy, especially in the Northern Hemisphere, potentially leading to additional warming for Europe and North America. Researchers stress that these trends must be integrated into climate models to better predict how global systems will respond and whether the Earth can restore its long-term energy balance.
