6.1
Albedo effect

Did you know?
Did you know that pollutants from eastern and southern Europe can travel as far north as Svalbard and east Greenland?
Did you know that forest fires far to the south send smoke and particles to the Arctic?
See story 5.1
Did you know that we can identify where the dust on the glacier comes from by its fingerprints?
See story 2.2
Did you know that there are many different types of pollutants reaching the Arctic?
See story 2.1

Get Active!
Black Ice Experiment
You will need:
Instructions
In one cup, fill with enough water to fill half of the ice cube tray.
In the other cup, fill with enough water to fill the other half of the ice cube tray. In this cup, add a few of drops of black food colouring until the water turns very black.
Fill one side of the ice cube tray with the clear water and the other half of the ice cube tray with the black water.
Wait a couple of hours until both sides of the ice cube tray have frozen solid.
Once frozen, remove the ice from its tray and put black ice into one bowl and clear ice into another bowl.
Put a lamp on top of both bowls, where the light is hitting both sets of ice equally – if your lamp is unable to do this, use two separate lamps/light sources, or you can put it outside if the sun is shining!
Time how long it takes for each bowl of ice to melt.
Why did one melt faster than the other?
In this experiment, the black ice represents ice and snow polluted by black carbon in the Arctic and the clear ice represents clean ice and snow in the Arctic. As we can see from this experiment, the colour of ice impacts its reflectivity and a darker colour can cause ice to melt much faster. This is important in the Arctic where areas of ice and snow are vast.
What exactly is black carbon?
Black carbon (BC) also known as soot, is small particles that are emitted into the atmosphere naturally, for example by wildfires as well as unnaturally, by humans burning diesel fuel. BC is particularly harmful to the environment in two ways, by turning white surfaces black (like Arctic ice and snow) and by warming the air in the atmosphere. For this experiment, we looked at how BC causes ice melt in the Arctic when it lands on ice and turns it a darker colour. BC is suggested to have caused more than 30% of warming in the Arctic.
How does BC melt ice?
When black carbon particles land on ice and snow, they make them much darker than the pure white we think of when we think of the Arctic . The darker surfaces reduce the Albedo, or reflectivity of the area.
What is the albedo effect?
Have you ever stepped outside on a hot day in a black T-Shirt and felt hotter than if you were in a white one? That is due to albedo. Albedo, translated into "whiteness" in Latin, is a term used to measure reflectivity. This is usually used on Earth to explain how surfaces reflect sunlight in order to cool down the planet, two of the most extensive surfaces that do this are snow and ice. White surfaces reflect light much more than darker surfaces. Therefore, when black carbon lands on snow and ice, less sunlight is reflected back into space. This causes the snow and ice to absorb more heat and melt much faster than they would if they were lighter in colour, meaning less reflection of sunlight is happening, causing even more melting and rising sea levels.
Ice is essential!
Ice is important as it reflects sunlight back into space to cool the Earth.
For animals, ice acts as a place to rest, birthing grounds and protection from predators such as the killer whale. Animals that highly depend on ice include polar bears, seals, walruses and even phytoplankton!
For humans, it acts as a way to hunt animals for food and clothing and even to establish floating research stations.
References