Increasing or decreasing amount of sunlight that is absorbed by...

• Increasing or decreasing amount of sunlight that is absorbed by different areas of the surface of the Earth. This can affect Earth’s temperature.
• Increasing or decreasing temperatures, which can alter the distribution of snow and ice cover. By increasing snow and ice cover, especially at high latitudes, the reflection of sunlight can increase, which in turn decreases the amount of light that is absorbed by Earth’s surface.
• Changes in the Earth system that are affected by snow and ice cover, including the carbon cycle, and how much carbon (including the greenhouse gas carbon dioxide) is transferred between the atmosphere, biosphere, and ocean.

from your link.

note that they refer to changing temperature. its this that is the important factor.

the site isn't trying to say that global warming isn't an important factor in climate change. the loss of ice is particularly relevant as this is caused by increased GHGs which the physics has shown increases the atmospheric temperature. this has resulted in ice melt which reduces the global albedo (reflectivity) and so oceans and land, once covered in ice/snow, now absorb more heat.

the increased oceanic temperature is the key indicator of the reduced ice coverage. its a tipping point MC.