2. Are you feelling HOT, HOT, HOT?

Hi to Everyone on ThinkQuest, from the sunny Caribbean! Picture this:

While in other countries it might be snowing right now, here in Puerto Rico (P.R.) is summer all year long! How can that be? Well, that happens because we are situated in the Caribbean in a region of the world known as the Tropics. Thanks of our Earth's inclination we receive most of the Sun's radiation, which gives our region it's characteristic year round sunny views, but also HOT climate.

That can become a problem for many of us, specially at our schools were temperatures inside our classrooms during the school year can reach above 90° Fahrenheit (32 °C).  Imagine at least 25 students, one teacher, no air conditioning and at least five fans all trying to cope with the same problem: HEAT!

Well, that is a problem that we intend to solve. So join us in our school project were we will become The Green Guards while we look for an ecological solution to one hot problem...

On the picture below you can see where in our world are the Tropics located. The Tropical Zone, it's defined as the zone that surrounds the Equator and extends from about 23.5° of latitude North to 23.5° latitude South. Is delimited on the North by the Tropic of Cancer and on the South by the Tropic of Capricorn (Earth Science, 2007).

Here in Puerto Rico our temperatures ranges from  71.1° F to 87.3° F  (Atlas Ambiental de Puerto Rico, 2007). Right now you might be thinking those temperatures are not that bad, but think about this:

• Our town of Peñuelas is located to the south, the driest and hottest area of the island.
• All our schools are made of concrete (which absorbs heat).
• Most classrooms on the island have no air conditioning systems.
• Our island's constant humidity can get as high as 82% (South East Regional Climate Center, 2007).

That translates that students and teachers, on a daily basis, feel much higher temperatures than the ones shown by thermometers, known as the Heat Index. Also affected by the heat island effect,  these can create a very hot, sweaty, and uncomfortable  environment inside our classrooms, which could affect students and teachers performance in the classroom.

Feeling the heat already?

As urban areas are being build, the environment around it changes: buildings, roads and other infrastructure replace green places and their vegetation, making the permeable and moist surface become a impermeable and dry one. These changes causes urban regions surfaces and atmosphere to become hotter than the rural surrounding ones. The difference of the temperature of this two forms is what is called the heat island effect.

According to the Environmental Protection Agency (EPA, 2009), on average, the difference in daytime sur­face temperatures between urban and rural areas is 18 to 27°F (10 to 15°C); the difference in nighttime surface tempera­tures is typically smaller, at 9 to 18°F (5 to 10°C). The EPA also notices that surface urban heat islands are typically present day and night, but tend to be strongest during the day when the sun is shining.

 A study in Atlanta, during a one-month period in July 1996, found that temperatures averaged 8–10°F higher in the urban area than in the surrounding rural areas. The heat island effect is most pronounced around sunset during spells of calm weather. This occurs when the greater vegetation surface area in rural locations allows greater radiative cooling to take place (Smith, J. 2011).

According to the online resource The free dictionary (2011),  relative humidity it's defined as the amount of water vapor found on a mass or sample of air, and depends strongly on the temperature of the place on that particular moment. Is expressed in percentages (%).

How this affect us? Well,  since warm air (and here on the tropics we have plenty of that) can hold more water vapor than cool air,  the largest the percentage of relative humidity present, the more sweaty you will get because you can evaporate less sweat from your body, making the heat more unbearable as you get more uncomfortable, sticky and even smelly! 

This, combined with the heat island effect can make our average 87.3 ° F temperature, feel much hotter.  And believe me, it happens. I LIVE HERE!!!!.