Albedo Alert!

 

Our planet has been warming up at an unprecedented rate. For the record, last year was the warmest. Ever. Scientists have been scrambling to understand exactly why.

We know that the extraordinary heat is fueled by the burning of fossil fuels and El Niño. However, these are not sufficient to explain the unusually rapid temperature rise.

Now a new study published in the journal Science says it has identified one more culprit, namely, the absence of clouds. Clouds reflect sunlight back into space and the fewer clouds results in more sunlight reaching the earth. “Albedo” is the fraction of lightthat a surface reflects. If all the light is reflected, the albedo is equal to 1. If 30% is reflected, the albedo is 0.3. The albedo of Earth's surface (atmosphere, ocean, land surfaces) determines how much incoming solar energy, or light, is immediately reflected back to space. This can have an impact on climate. 

Apparently, this recent rapid surge in warming is being supercharged by a dearth of low-lying clouds over the oceans. Low-level clouds tend to thrive in a cool and moist lower atmosphere. As the planet’s surface heats up, this can cause them to thin or dissipate entirely, setting up a complicated feedback loop where low clouds are disappearing because of global warming, and their disappearance then drives further warming. If this is happening, futurewarming projections may be underestimated and “we should expect rather intensewarming in the future.”