We’ve been living in a car, parked in the same lot, for the entire day. The intense June sunlight amplifies the heat inside as we sweat and suffer. This is the case for our earth; the sun scorches its surface and atmosphere.

Although it makes Earth an optimal place for numerous lives, it often causes a wide spectrum of human health conditions, including heat rash, heat strokes, and heat cramps.

What exactly happens to the surface and atmosphere during this phenomenon? The word that explains this is albedo. Albedo refers to the ability of a surface to reflect incoming light energy. Specifically, A surface with a high albedo reflects a larger proportion of the light energy, resulting in a relatively lower temperature than those with a low albedo. Generally, urban areas have a lower albedo than natural landscapes due to the darker color of artificial architecture, including paved roads, building tops, and parking lots. This is one of the causes of the heated environment of urban areas, referred to as urban heat island effect.

There are a variety of ways to cope with this extremely high temperature in urban areas.

One approach is to alter the albedo of the surfaces through a physical replacement. In the cases of buildings, gray paints can be replaced with white paints, reducing the absorption of light energy into the building surfaces. Ultimately, the light energy is reflected back rather than being stored and converted into heat. For example, Los Angeles has been taking the initiative in applying this method on a municipal scale. So-called Cool Pavement, presented by The Los Angeles Bureau of Street Services, applies a lighter color of pavement coatings on entire city roads with the aim of reducing city temperature during the daytime of summer.

Though coating buildings with a lighter color is universally applicable and well-known by many urban planning experts, painting roads white has been entailing controversies and criticisms from the masses.

Recent studies state that white pavement can make people feel hotter, since the light energy reflected from white pavement is in fact absorbed by people walking around rather than disappearing into the atmosphere. Furthermore, White roads can significantly damage the city’s aesthetics when dust and stains accumulate, and the costs to maintain their appearance are considerable.

<Yangha Yu Northwood / 11th Grade>