Climate change : less light reflected from earth

A recent study Climate change is causing less light reflected from Earth

An image taken from the International Space Station in 2011 of Earth's brightness on the Moon (NASA)

Suggests a recent study published in the journal "Geophysical Research in Letters" (Geophysical Research Letters) on August 29 / August last that the acceleration of climate change on the ground negatively affects the brightness. Earthshine refers to the light that is reflected from the Earth on the dark side of the Moon, which is also called Earthshine.

Clouds and the brightness of the earth

Because they reflect about half of the sunlight that strikes them, clouds are a complex part of the climate puzzle, which has prompted scientists to investigate how they respond to climate change and see how this response will affect climate in the future.

In their new study, researchers from the New Jersey Institute of Technology in California, USA, focused on studying the link between the Earth's brightness and the movement of clouds over the Pacific Ocean.

And as stated in a report - published on the "Live Science" website - the team of researchers relied on observational data from satellites, in addition to observations recorded over two decades of the "sunshine of the earth" phenomenon.

Scientists at the Big Bear Solar Observatory in southern California have been studying how Earth's brightness fluctuates since 1998. They note that these measurements are only relative, and more accurate data, whether from a lunar observatory or from a satellite, must be used. Miniature, or the so-called "space cube" (cubesat).

Thus, the researchers used data from the Clouds and Earth Radiant Energy System (CERES) Project of NASA's Earth Observation Analysis Unit, which has been operating since 1997 with instruments from a group of NASA satellites and the National Oceanic and Atmospheric Administration (NOAA).

The brightness of the earth and the brightness of the sun

Examining the two sets of data, the team found that the amount of light reflected off the Earth had decreased over the course of two decades, by roughly 0.5%, or half a watt of light per square metre.

Monitoring data from satellites has shown that most of this change has occurred during the last three years of data the team examined in 2017, while data from the Clouds and Earth's Radiant Energy System project show a sharper decline as they end into 2019.

Data from the Earth's Clouds and Radioactive Energy System Project also showed the disappearance of bright clouds at low altitudes over the eastern Pacific Ocean off the western coast of the Americas, where scientists are also recording sharp increases in ocean surface temperatures.

And when the light is not reflected back into space, this means that it will remain confined to the Earth, which may increase the pace of climate change that we are currently witnessing.

Finally, it is necessary to highlight an important result as well, which is summarized in the independence of the brightness of the Earth from the brightness of the sun, as the latter witnessed two events of inactivity and extreme activity in the period in which these data were monitored, but this was not related - in any way - to a decrease in the brightness of the Earth. Reflection of light off the ground. Therefore, scientists believe that the change in the amount of light reflected by the Earth must come from a change in the Earth itself.