| 2004 Carbon Dioxide Trends in Salt Lake City | |||||||||
| By:Aaron Guercio, Diane Pataki, Andrew Schauer | |||||||||
| Introduction: This poster displays some of the 2004 data gathered as part of the multi-disciplinary UTES project (Urban Trace Gas Emissions Study). One of the goals of this project is to better understand carbon dioxide dynamics in an urban setting. CO2 is an excellent tracer of atmospheric pollutants and greenhouse gases. Likewise CO2 is an important study species due to its own role in climate change. | |||||||||
| The Salt Lake Valley was chosen for this study due to its geographic diversity. The valley is literally a basin, surrounded by mountains. Within the basin can be found urban, suburban, and rural regions. The Salt Lake Valley is one of the few areas in North America where urban growth is expanding directly onto undeveloped rural land. Sites were selected throughout the valley to exploit this diversity. Site A (University of Utah) is a suburban site characterized by individual homes and mature cultivated tree coverage. Site B (Downtown SLC) is an urban local, complete with skyscrapers, traffic, and few 'green' spaces. Site C (Kennecott farmland) is rural and dominated by winter wheat fields. | |||||||||
| Site A: (University of Utah) Suburban site. | |||||||||
| Site B: (Downtown SLC Library) Urban site. | |||||||||
| Site C: (Kennecott) Rural site. | |||||||||
| 5-minute CO2 Concentration Data from Urban Local (Site B). Note the higher peak concentrations in relation to the other sites. Likewise inversion events can be seen in the elevated baseline concentrations in the winter. The black line at the bottom of the plot are 'background' CO2 concentration data from Wendover Utah (provided by NOAA CMDL). | |||||||||
| 5-minute CO2 Concentration Data from Suburban Local (Site A). This site has intermediate peak CO2 concentrations in relation to the urban and rural sites. Inversion events are still visible in the winter months. | |||||||||
| 5-minute CO2 Concentration Data from Rural Local (Site C). Low CO2 concentrations characterize this site year-round. Data are very near to background concentrations recorded at Wendover. | |||||||||
| Data were collected every five minutes at the three sites using the CO2 'profiler' system seen at the right. When this system is coupled with 2 calibration tanks, buffer volumes, and controlled temperature environments, data accuracy is typically within 0.5 ppm, often better. | |||||||||
| The data at each site clearly show diurnal and seasonal trends in CO2 concentrations across the Salt Lake Valley. On a daily basis concentration spikes appear during peak commuting times, showing some of the human impact on carbon dynamics. Likewise the effect of photosynthetic activity in reducing CO2 concentrations can be seen between sunrise and sunset of each day. On a larger scale, winter CO2 concentrations illustrate the cumulative effects of natural gas combustion for heating homes, gasoline combustion during the commute, and reduced photosynthetic activity due to low temperature. This results in elevated CO2 concentrations as well as occasional massive spikes. Storm fronts, inversions, temperature gradients, even wildfires can be seen in the data. Clearly intensive monitoring of CO2 concentrations is an important tool in understanding pollution dynamics as well as climate change. Data gathered from CO2 networks like that of Salt Lake City will provide ideas on how best to combat the aforementioned problems, as well guidance to planning commissions on preventative measures they can take as they participate in city planning and zoning. The Salt Lake CO2 monitoring network has been expanded to five stations, each providing online, real-time, CO2 concentration data as well as meteorological data. The network can be found at: http://ecophys.biology.utah.edu/CO2SLC/CO2SLCmap.html | |||||||||