What is Albedo and How Does it Affect Climate? (Credit: NOAA Climate, National Snow and Ice Data Center)
Factors that inflict climatic changes Part 2:
Part 1 here
DISCUSSION: Ever wonder why it is difficult to see when a fresh coat of snow blankets the ground as opposed to a dark colored highway? The reflectiveness of snow is much higher than the absorptive properties that dark colored surfaces possess. A name for this reflective behavior is albedo. Albedo plays a crucial role in the climate system for it explains why certain surfaces either absorb sunlight or reflect sunlight.
Albedo is more scientifically defined as the amount of solar radiation reflected from an object or surface. The reflection is usually presented as a percentage. Some hear about albedo happening in lower latitudes, but the majority of albedo news happens in higher latitudes where snow and ice coverage outweigh everywhere else. Albedo directly affects the climate of higher latitudes by the amount of solar radiation being absorbed or reflected. If more solar radiation is absorbed, then the overall climate will start to warm due to the heat being absorbed.
Albedo participates in something called a feedback loop. This feedback loop is the act of less ice reflecting less sunlight, resulting in continuous warming. This cyclical loop is a continual warming trend that results in the melting of ice and snow which will inevitably lower the albedo, thus warming the region. The melting of land ice due to lower albedo will result in darker ocean being exposed, further exploiting solar radiation by absorbing its heating capabilities. Of course, the heating of the ocean will result in the melting of land and sea ice. As noted above, this produces a cyclical loop of warming and melting.
The average global albedo is roughly around 30%. Meaning, 30% of incoming solar radiation is being reflected back out to the atmosphere. However, in the Arctic, with more prevalent areas of snow and ice, the albedo percentage increases to about 70%. In other words, 70% of incoming solar radiation being reflected back out due to the reflective behaviors of white snow and ice. This high albedo percentage helps keep the Arctic cool and reduces the melt period of glaciers, sea and land ice. In recent years, there has been a decrease in land and sea ice in the Arctic resulting in less reflective surfaces. This gives way for less reflective ocean water to take its place. The albedo percentage of ocean water is roughly around 6%. Roughly 94% of incoming solar radiation is absorbed by the oceans which then contributes to its warming.
Albedo plays a role on climate by directly contributing to either cooling or warming a given area depending on the percentage of albedo. In an age with a continual warming trend in the Arctic, much greater than anywhere else, it will be interesting to study and research further albedo statistical data and learn about its continual effect on climate.
To learn more about other interesting stories related to global climate issues, be sure to click on the following link: www.globalweatherclimatecenter.com/climate
©2018 Weather Forecaster Alec Kownacki
Leave a Reply.