NEW DELHI: As per a study published in the journal named Geophysical Research Letters, warming oceans have caused a decrease in Earth’s brightness. The study found that Earth is now reflecting about half a watt less light per square metre than 20 years ago. The study used decades of earthshine measurement, which is light reflected from Earth which illuminates the surface of the moon.
Researchers studied satellite measurements and found that there has been a significant drop in Earth’s reflectance, or albedo, over the past two decades. It found that Earth is now reflecting almost half a watt less light per square metre than it did 20 years ago. The study also added that most of this drop has occurred in the last three years of the earth shine data.
Philip Goode, Researcher, New Jersey Institute of Technology, said that the drop in albedo came as a surprise to scientists when the data was analysed of the last three years after 17 years of nearly flat albedo. The researchers added that dimming of the Earth can also be seen in terms of the amount of solar energy captured by Earth’s climate system.
Goode added that once the additional solar energy is in the Earth’s atmosphere and oceans, it can contribute to global warming. This is because the extra sunlight is of almost same magnitude as the total anthropogenic climate forcing over the last two decades, the researchers added.