What is the Heat Island effect?

The Heat Island effect, also referred to as the effect of the urban thermal island, is a situation where the average temperature of the area is higher than in the vicinity of rural areas. In most cases, this is due to the fact that materials in urban areas such as concrete and asphalt absorb a lot of sunlight and store them in large thermal materials. The secondary cause is the heat of waste heat generated by massive energy use. The accumulation of heat affects not only the city itself, but also on the surrounding areas of the wind, which generally sees by 10% by up to 30% of the annual rainfall than the up area. The difference in urban temperatures compared to the regional average is most visible at night and especially during winter. One of the main causes of the elevated temperature is that in the urban environment of a large building block a large part of the sky, which is much cooler on Night than Earth, so the heat does not diminish as quickly as in rural areas without large buildings.

Another cause is the introduction of large rows of new materials that absorb and maintain thermal energy from the sun. For example, asphalt absorbs much more sunlight than normal ground, thanks to its dark color, and asphalt and concrete tend to maintain heat much better than the average stain of the Earth. As a result, sunlight is absorbed as heat into parking, sidewalks and streets and distraction takes much longer than the surrounding continuous regions.

There are significant health risks associated with the thermal island and, depending on the region, mortality during thermal waves in urban areas may be significantly increased. Already high temperatures can rise even higher, because heat is absorbed and imprisoned in cities and without the prepared output of to bleeding at night, for those who were affected by heat, there may be little relief. Although only about 1,000 deaths of extreme heat are in the United States, it is considered to be a significant part of them caused by increasedMi temperatures of the urban environment.

Maybe even more dramatic are the financial cost of Heat Island. Higher temperatures during the summer mean increased electricity costs per energy to keep the interiors cold. The city in Los Angeles estimates that this phenomenon is spent every year for another $ 100 million (USD) every year. As a result, several innovative cooling programs were designed to reduce the annual costs and to increase their standard of living.

planting trees that reflect light and cool the environment, using lighter color surfaces, planting living roofs and coating roads with reflective layer are generally used tactics to reduce the effect of the thermal island. In the CEN program from Los Angeles, one proposed program focuses on spending $ 1 billion USD for harassment of approximately a quarter of the road in the city, setting ten million trees and deploying five million houses. Annual savings are estimated at approximately $ 170 million in e ENergia and for another $ 360 million in healthcare, while the project pays for only two years.