Modern satellites are shaping the course of climate science

Fast forward to 2022, and we are now launching more than a thousand satellites into space each year, improving our weather forecasts, boosting our internet coverage and propelling the field of Earth science into new terrain.

The idea of using satellites to gain a new perspective on our planet began with the launch of Sputnik 1, which transmitted radio signals from orbit that scientists used to gain new insights into the ionosphere.

The scientists tapped into data from satellites tracking monthly changes in the Earth’s gravitational field for a more accurate understanding of the seasonal shifts in the sheet’s mass, to understand the impending impact on global sea levels as it melts.

With more than 150 satellites currently observing the Earth from orbit and more on the way, the toolkit for climate scientists continues to grow more versatile.

“Over the last 20 years, GRACE and GRACE-FO missions have monitored global changes in Earth’s mass every month. This has resulted in far-reaching impacts to our understanding of the distribution of water on our planet and how that’s changed over the years. Both satellites are essentially ‘smart water meters’ in space that measure month-to-month changes in the mass of ice sheets and glaciers, near-surface and underground water storage, the amount of water in large lakes and rivers, as well as changes in sea level.”

“The depth indicates the total volume of the melt water and how ‘mature’ they are. Melt ponds are key aspects of sea ice because they lower the reflectivity of the surface and that leads to more energy being absorbed by the surface. This leads to more melt and earlier loss of sea ice. Such depth data has not been available from satellites before ICESat-2.”.

By tracking things like changes in sea ice coverage or the mass of ice sheets, scientists can get an idea of how the Earth’s climate is changing, and what course it might take into the future.