Albedo

The fraction of incoming sunlight a surface reflects back to space, from 0 (pitch black, absorbs everything) to 1 (perfect mirror). Fresh snow is high; dark forest and open ocean are low.

Why it matters

Albedo controls how much solar energy the planet keeps versus bounces away, so it is central to climate — shrinking bright ice exposes darker water and land, which absorb more heat and amplify warming.

Where you’ll meet it

• MODIS produces a widely used global albedo product, accounting for how reflectance changes with sun and view angle.
• VIIRS continues MODIS-style albedo measurements for ongoing climate records.
• Landsat surface reflectance supports albedo estimates at finer, field scale.

In plain terms

It’s like wearing a white shirt versus a black shirt on a sunny day — the white one bounces the heat away, the black one soaks it up.