solar radiation budget and the maximum uhi levels of the metropolitan area
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Solar radiation budget and the maximum UHI levels of the Metropolitan area. Tahsina Islam No Mentor. UHI. Urban heat island: Comparison of non-urban and urban temperatures Absolute value: Urban temperature (minus) rural temperature (equals) urban heat island Compared: spacial scales - PowerPoint PPT PresentationTRANSCRIPT
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Solar radiation budget and the maximum UHI levels of the Metropolitan areaTahsina Islam
No MentorUHIUrban heat island:Comparison of non-urban and urban temperaturesAbsolute value: Urban temperature (minus) rural temperature (equals) urban heat island
Compared: spacial scalestimes scalesradiometric scalesmaps of surface temperature from remote sensingshows direct comparison between urban and non-urban areas
Variations in New York citys urban heat island strength over time and spaceS. R. Gaffin1, C. Rosenzweig1, R. Khanbilvardi2, L. Parshall1, S. Mahani2, H. Glickman2, R. Goldberg1, R. Blake3, R. B. Slosberg4, D. Hillel1
Quantifying the influence of land-use and surface characteristics on spatial variability in the urban heat islandMelissa A. Hart & David J. SailorPortland, Oregon
Vehicle temperature traverses were used to determine spatial differences in summertime air temperature across the metropolitan area in the afternoon.
Materials and Methods
Results
Magnitude of Temperatures
Magnitude of UHI levelsAssessment of the Urban Heat Island in Casa Grande, Arizona Brent C. Hedquist, Department of Geography, Arizona State University
Early studies : T(u-r) (difference between background rural and highest urban temperatures) is directly related to city size (Oke 1973).
For North American and European settlements, the following equation illustrates how a prediction of the maximum heat island, or T(u-r)(max), can be made by taking the log of the population (p):The optimal equation, which explains the most variance in the maximum heat island and includes average wind speed is:
Materials and Mathods
4 day period
March 15 18 2004
Fixed Station versus 9 areas chosen by researchers
Fixed Station Asos III National Weather Service Station
Results
SOLAR RADIATION AND URBAN HEAT ISLANDSWERNER H. TERJUNG AND STELLA S-F. LOUIE
top of one building (w1), continues down the side of that building h1, crosses the street d, ascends the side of the second building h., and terminates on the top of the latter we
Calculations continued
Research Proposal Problem: What would be the maximum UHI levels of 5 stations in the metropolitan area?In these areas what would be the radiation budget compared to Manhattan?
Hypothesis: The maximum UHI levels would correlate with the previous UHI levels taken. Manhattan's radiation budget would be much less as the buildings are so much tallerMaterials and Methods
8 suburban areas approximately100 km away from Central Park in NYCHOBO RH/Temperature Sensors in each location variable proofAverage of all 8 areas- control groupEach Metropolitan area experimental groups
Control Group: Manhattan radiation budgetExperimental Group: 5 areas selected outside of Manhatten
Results
Variable taken into consideration: Trees add to the amount of shade and lessen radiation budgetResults: Maximum UHIMax UHI will correlate with the UHI levels of previous research of each stationNot much difference occurs in UHI from 2002 recordOcean Parkway would have highest max UHIW 56th ST would have lowest max UHI
DiscussionUHI is important in understanding NYCs climate changeContributes to PLANYC 2030 : Climate Change goals being reachedKnowing how NYC ranks amongst other cities around the worldEvaluate how much NYC is contributing to global warming
Citations Oke, T.R., 1981. Canyon geometry and the nocturnal UHI: comparison of scale model and field observations. Journal of Climatology, 1 (14), 237254.Santamouris, M., et al., 2001. On the impact of urban climate on the energy consumption of buildings. Solar Energy,70 (3), 210216.Williamson, T.J. and Erell, E., 2001. Thermal performance simulation and the urban microclimate: measurements andprediction. In: Proceedings of 7th IBPSA. Rio de Janeiro, Brazil: International Building Performance Simulation Association, 159166.Hedquist, Brent C. "Assessment of the Urban Heat Island in Casa Grande, Arizona." Journal of the Arizona-Nevada Academy of Science 38.1 (2005): 29-39. JSTOR. Web. 20 June 2010. .Terjung, Werner H., and Stella S-F Louie. "Solar Radiation and Urban Heat Islands." Annals of the Association of American Geographers 63.2 (1973): 181-207. JSTOR. Web. 20 June 2010. .