Subscribe Now

On a hot summer day in the United States, a traditional roof can get as hot as 185 degrees! Hot roofs contribute to the urban heat island effect, where temperatures in cities are warmer that surrounding natural areas. One way to reduce the urban heat island effect in cities is to install cool roofs, using [...]

On hot, sunny days, surface temperatures of roofs and pavement can be from 50 to 90 degrees Fahrenheit warmer than the air temperature! These hot surfaces contribute to “urban heat islands” where temperatures in cities are hotter than surrounding, less developed areas. The urban heat island effect can be particularly pronounced at night, when city [...]

Urban areas have more buildings, roads, parking lots and sidewalks than rural areas.  These hard surfaces trap heat, raising temperatures in cities by as much as five degrees Fahrenheit.  Higher temperatures in cities – known as “heat islands” – can increase the amount of energy used for air conditioning, increase air pollution levels and raise [...]

Rising temperatures can take a toll on our bodies. Usually, your body cools as perspiration evaporates off your skin. But on extremely hot days, evaporation slows and your body has to work harder to maintain a normal body temperature. The American Meteorological Society estimates that up to 1,000 people die each year from heat-related illnesses; [...]

Urban heat islands form as vegetation is replaced by asphalt, concrete and other “hard” surfaces for infrastructure like roads and buildings. These surfaces absorb rather than reflect incoming heat from the sun, causing overall urban temperatures to rise. Rising temperatures increase demand for energy for air conditioning, contribute to the creation of ground-level ozone air [...]

Thermal pollution and thermal shocks are caused by increasing or lowering the temperature of water, which can harm aquatic life.  Many aquatic animals depend on a particular temperature to reproduce and survive, and they can die even if temperatures change even slightly. Warmer water can also decrease dissolved oxygen levels, making it difficult for some [...]

“Heat islands” around urban areas form as vegetation is replaced by asphalt and concrete for roads, buildings and other infrastructure. These hard, dark surfaces absorb rather than reflect incoming heat from the sun, causing overall urban temperatures to rise. During hot weather spells, the heat island effect can raise urban temperatures by two to ten [...]

Did you know that more than 90 percent of roofs in the U.S. are dark-colored?  Dark colors absorb and hold on to heat from the sun, rather than reflecting it.  This means that at midday during the summer, dark roofing materials can warm up to between 150 and 190 degrees Fahrenheit!  A hot roof can [...]

During the heat of summer, shade from trees helps cool us and our homes.  Trees can also pay dividends by shading our streets, which keeps pavement in better condition.  Shaded streets require less maintenance and can save up to 60 percent on repaving costs over a 30-year period!  Shade from trees also cools pavements, lessening [...]

In an average summer in the U.S., about 1500 people die from excesssive heat events.  Excessive heat may disproportionately affect people in cities, where paved roads, buildings, and other “hard” surfaces absorb and trap heat from the sun.  This “urban heat island effect” means that cities do not cool down at night like rural areas do, offering [...]

Did you know that the temperature inside a car can rise by up to 40 degrees in one hour, even when outdoor temperatures are as low as 72 degrees Fahrenheit?  When the sun shines on car windows, they collect light and trap heat inside the vehicle, raising temperature quickly.  And, as the outdoor temperature rises, the effect becomes [...]

During the heat of summer, shade from trees helps cool us and our homes.  Trees can also pay dividends by shading our streets, which keeps pavement in better condition.  Shaded streets require less maintenance and can save up to 60 percent on repaving costs over a 30-year period!  Shade from trees also cools pavements, lessening the urban heat island effect [...]

Did you know that the human body has about three million sweat glandsSweating cools your body when water on the skin is removed by evaporation. Unfortunately, when hot weather is coupled with high relative humidity, your body’s cooling system doesn’t work as well because humidity slows evaporation.  Other factors also impact your body’s ability to cool, including [...]

According to estimates based on the 1990 population, extreme heat events cause close to 2,000 deaths in the U.S. every year, and 79 of these deaths occur in the St. Louis Metropolitan Area.  The elderly, infants, and people with disabilities or chronic illnesses, particularly those lacking air conditioning and transportation, and living alone, account for [...]

The National Weather Service uses the “Heat Index” to indicate how hot the weather feels to the body when temperature and humidity are taken into account.  It is important to remember, however, that the values in the Heat Index are calculated for shady conditions – it can feel up to 15 degrees hotter in direct [...]

According to estimates based on the 1990 population, extreme heat events cause close to 2,000 deaths in the U.S. every year; 17 of these deaths happen in the Louisville Metropolitan Area. If you lack air conditioning and live in an upper floor of a building, especially a building with a dark roof that is surrounded [...]

The National Weather Service uses the “Heat Index” to indicate how hot the weather feels to the body when temperature and humidity are taken into account.  It is important to remember, however, that the values in the Heat Index are calculated for shady conditions – it can feel up to 15 degrees hotter in direct [...]

In many U.S. cities, summertime temperatures can be up to 10 degrees warmer than surrounding natural areas, creating “urban heat islands.”  The structure of cities plays a major role in the development of heat islands – dark pavement and buildings absorb and trap heat, narrow streets with tall buildings can trap heat and reduce wind [...]

Did you know that urban heat islands – where pavement and buildings absorb and trap heat, making cities feel warmer than surrounding natural areas – can actually affect Houston’s weather patterns?  Scientists have found that urban heat islands cause warm air to rise, and when this air reacts with sea breezes, it creates more frequent, [...]

Pavement and buildings in cities absorb and trap heat, and temperatures can be several degrees warmer in the city than surrounding natural areas. At night, these “hard” surfaces gradually release stored heat and raise night time temperatures, offering little relief during hot weather events. Viewer Tip: Asphalt, tar, and other dark pavement and roof surfaces [...]