Albedo Effect, the Science Behind Climate Change
One of the most simple concepts that plays the most complicated role in the state of our ever-changing environment
By Nishant Sharma
Climate change is a dynamic issue that, now more than ever, poses a huge threat to us all. The planet is warming to a degree beyond what many species can handle. This has catastrophic effects; few include: altering or eliminating habitat, reducing food sources, causing drought and other species-harming severe weather events, and even directly killing species that simply can’t stand the heat. When it comes to global warming there are certain risks that we can curtail — like carbon emissions. However, there are some factors that are out of our control and so we must do what we can to mitigate the risks that endanger the entire human race. The media has played a huge role in the dissemination of knowledge regarding carbon emissions, energy efficiency, recycling and many more actionable factors. However, it is also pivotal to understand the elements that are a part of nature’s balance. One of these concepts that are often overlooked, is the albedo effect.
The term ‘albedo’ is derived from the Latin for ‘whiteness’. In essence, albedo is the reflectivity of a certain object. With regards to climate change, it is a measure of the total amount of sunlight (solar radiation) reflected by a surface. The implications of the albedo effect can be seen in our everyday routines. The basic principle is analogous to strategies employed by people who live in hot places. Buildings are constructed with white exteriors, as white surfaces have a higher albedo: they reflect a larger amount of sunlight back into space. People wear light colours in summer rather than dark ones for the same reason (Shell, 2011). The albedo of the entire Earth’s surface is the predominant factor that contributes to climate change, and the rise in global temperature. The Earth’s surface contains a vast array of shades, right from the dazzling white of ice and snow, to the dark surfaces of oceans and forests. Each biome has its own unique impact on the Earth’s temperature. Most light is reflected back by the snow and ice, while the darker oceans absorb energy. The absorption of light by dark water bodies is a natural process that humans have taken for granted for over a century now. Oceans help keep the Earth warm because they absorb a lot of heat (approximately 90%). This warming increases water vapour, which acts as a greenhouse gas and helps to keep temperatures within optimum ranges.
The problem arises when the ice caps start to melt. Apart from the Antarctic-sea ice (increasing by approximately 1% per year), nearly all the ice on the planet is melting. As the area of white, reflective surfaces decreases, more radiation is absorbed by the earth. Thus increasing temperature to an extreme level. Furthermore, the loss of Arctic ice is not only a point of concern surrounding the albedo effect, but it also instigates a positive feedback loop. With the increase in ice-melt, the temperature of the water increases. As a result, this melts the ice from underneath, while man-made CO2 emissions in the atmosphere warm the surface. Furthermore, an increase in humidity positive correlates to the quantity of water vapour — a potent greenhouse gas — which melts, even more, ice, in turn restarting the entire loop. Each repeat of this perilous feedback loop gets more and more pronounced. Regardless, an increase in water vapour can also be attributed to an increase in the number of clouds. It isn’t just the earth’s surface that has reflective qualities. Clouds have an extremely contrasting role with regards to maintaining global temperature. On one hand, they help reflect sunlight, contributing to the cooling of the albedo effect. But on the other hand, they also contribute to the retainment of heat due to the high concentration of condensed water vapour.
As mentioned previously, the albedo effect is an ecological constituent and plays an important role in many environmental processes. However, what are we as humans doing to interfere with this natural process? The most evident form of involvement is the sharp increase in carbon emissions all across the world. The rising atmospheric CO2 concentration has catastrophic impacts on optimum global temperature. The rise in temperature, due to increased CO2 emissions, in turn, amplifies arctic ice-melt. Consequently influencing a huge reduction in the area of “reflectable” surfaces such as glaciers, and other forms of ice. Furthermore the looming threat of overpopulation, ultimately instigating a sharp increase in urbanization levels, is also a huge factor that contributes to the albedo effect. Highly developed areas such as urban cities can experience higher average temperatures than the surrounding suburban or rural areas. This phenomenon is also known as the “heat island effect” (North Carolina Climate Office, 2015). The abundance of darker materials such as concrete and asphalt used to construct pavements, roofs, and roads significantly decrease the albedo of the urban area (more heat is absorbed). Thus resulting in an increase in temperature. Moreover, the absence of vegetation also contributes to the heat island effect. Trees, green roofs, and vegetation can help reduce urban heat island effects by shading building surfaces, deflecting radiation from the sun, and releasing moisture into the atmosphere (EPA, 2015).
Ultimately it all boils down to society, and whether we choose to take action, or choose the easy, convenient way out. We’re the ones who chose to interfere with natural processes. And for what? Material gain? Personal interest? In the end, coexistence with the environment is one of the most essential things. Destroying forests, oceans, and ice-caps aren’t going to get us anywhere. “In the end, you will be your own undoing. You can’t escape you” — Ted Dekker. If we don’t change now, we will be the cause of our own downfall.
Works Cited
Cain, Fraser. “Albedo Effect.” Universe Today, 25 Dec. 2015, www.universetoday.com/39937/albedo-effect/.
“Climate Science Glossary.” Skeptical Science, www.skepticalscience.com/earth-albedo-effect.htm.
GnY, et al. “The Albedo Effect and the Reflectance of Solar Heat.” Geography and You, 17 May 2018, geographyandyou.com/reflectance-of-solar-heat/.
“National Snow and Ice Data Center.” Thermodynamics: Albedo | National Snow and Ice Data Center, nsidc.org/cryosphere/seaice/processes/albedo.html.
Perkins, Sid. “Core Concept: Albedo Is a Simple Concept That Plays Complicated Roles in Climate and Astronomy.” PNAS, National Academy of Sciences, 17 Dec. 2019, www.pnas.org/content/116/51/25369.
