Uploaded on 2017-09-15 by Maria Alejandra López

1. Check the temperature differences in US cities SUMMER IN THE CITIES - Raleigh: The city is up to 19.0° hotter than in nearby areas. In average, is 1,8° hotter than rural areas. The city has 2 more days above 90°F each year than rural areas. - Charlotte: The city is up to 12.0° hotter than in nearby areas. In average, is -1,4° cooler than rural areas. The city has 16 fewer days above 90°F each year than rural areas. - Chicago: The city is up to 21.0° hotter than in nearby areas. In average, is 2,2° hotter than rural areas. The city has 8 more days above 90°F each year than rural areas. - Dallas: The city is up to 19.0° hotter than in nearby areas. In average, is 3,8° hotter than rural areas. The city has 39 more days above 90°F each year than rural areas. - Washington DC: The city is up to 21.0° hotter than in nearby areas. In average, is 4,7° hotter than rural areas. The city has 17 more days above 90°F each year than rural areas. This is also de No. 6 biggest difference between urban and rural temperatures. 2. Which are the main UHI effects that you can identify in your area? Colombia tracks the changes in the weather and environment in general through the analysis provided by IDEAM (Instituto de Hidrología, Meteorología y Estudios Ambientales) which is the institute in charge of hydrology, meteorology and environmental studies, that’s why in the case of Bogota, my place of residence, they have noticed that the heat island effect has increased the temperature 2°C higher than the surrounding rural are, according to a study from 2007. The average temperature of Bogotá used to be 13°, and according to those measurements the temperature is now around 13,2°C and 14,4°C, and could rise up to 15°C or 16°C by the year 2050. In fact, on February 8th of 2017, was registered the highest temperature in Bogota, around 2 p.m the temperature was 25°C, this was caused by different factors, among them is the cloudiness that was decreased by that time in the country, which has increased the radiation and the maximum temperatures in the urban areas. In the image 1 you can see that Bogotá is a very dense city, you can tell by of the quantity of buildings, roads and population. The asphalt on the streets is a big contributor to the heat island of the city due to the absorption of the heat in the hotter days, because materials like this and brick and concrete seal the soil and make it impervious, also de pollution created by the public transportation and the contamination made by the industry of bricks. The two main heat islands in Bogotá are located, one in the south of Bogotá named Bosa, and the second one is in the center of the city, here the streets let the solar radiation pass through so the cooling demand is higher. In the second image you can see the rural part in the surroundings of the city, where the field is use for farms and it helps to mitigate the contamination created by the city and absorbing all the CO2 spread along the territory, here people is trying to protect their land because of the threat of fast growing real state, trying to build and expand the city, covering this lands with asphalt and concrete and increasing the heat island effect in the city. 3. Which are the measures you would purpose? I would set a plan to work on the light color of facades and roofs, in that way the solar radiation is not stuck on this surfaces and the inner spaces could be more comfortable for people. Also plant more trees along the streets and public spaces increasing the green spaces to mitigate also the heat island canopy layer effect and keep the streets cool during the hotter days, in that way it’s possible to save some money on energy used for cooling spaces. One important thing that I would like to promote is the use of pervious concretes for the streets, this allows the streets to be cooler and let the soil breath. Is also helpful if some streets can be painted with a light color so it can produce the same effect with the roofs and facades light painted. Also I would like to promote the use and design of green roofs and urban gardens on the buildings, all these green spaces contribute also for the absorption of the CO2 in the air caused by pollution. And finally, I think is important to understand that de density of buildings in the city is a major factor that increases the heat island effect, that is why is more important to stablish all these strategies in the city already built, instead of thinking that the solution is to expand the city to let it breath, which is an idea that is only causing damages in the rural area around the city. 4. Is UHI effect concerning policy making in your area? A few years ago was created the PNACC (Plan Nacional de Adaptación al Cambio Climático), which is a plan that has the finality to reduce the vulnerability of the country and increase its capacity of action to the threats and impacts of the climate change, this plan has contributed with the strengthening of the management of the participant institutions like IDEAM and the Ministry of Environment, Housing and Territorial Development, enhancing the technological, technical and professional capacity of them, generating basic and specialized information for the country, for the sectoral and territorial planning that includes from strategies and plans of adaptation to the biophysical and ecosystemic conditions of the areas, to the sociocultural aspects of the population in the area. Another important strategy that is being applied in Bogotá and the region that the city is in, is the regional development strategy that is called “Mesa de Planificación Regional Bogotá-Cundinamarca” which, in 2005, developed three possible scenarios, and defined one of them as the most desirable one, the scenario of the “network of compact and autonomous cities”, this scenario explores the reinforcement of the links that exit in between the cities, territories, and neighboring departments. That is why it promotes the distribution of the development in several strategic points all around the region of Cundinamarca. All these strategies tend to strengthen the resilience of the territory to absorb without any trauma all the emissions of greenhouse gases, mitigating the urban heat island and taking a stand on the matter of climate change.