Ozone Investigations on the Lower Troposphere. by Farhana Nabi. Abstract. Tropospheric Ozone. Stratospheric Ozone. Data/Results. Considered as “good ozone”. Lies from 12 km – 50 km above the sea level. Formation:
by Farhana Nabi
Continuing investigations of ozone concentrations in the lower troposphere are underway to ozone concentrations in New York City. The objective of these experiments is to determine factors related to the variability on the concentrations of ozone in the atmosphere. The emphasis of this investigation is on the relationship between the urban heat island effect and ozone concentrations in the New York City metropolitan. Relevant parameters include ozone partial pressure, temperature, humidity, pressure, ozone mixing ratio, wind direction, and wind speed. The data is retrieved from sounding launches at the Brookhaven National Laboratory. The two main instruments for the soundings are a radiosonde and an ozonesonde. The ozone data is also being correlated with satellite imagery and surface ozone observations from the EPA.
What is Ozone?
In order to gather data on the concentrations of ozone in New York City, several sounding balloon were launched at Brookhaven National Laboratory.
What is the Urban Heat Island Effect?
The objective was to determine how meteorological variables affect ozone concentration and to make preliminary observations on the effects of the urban heat island (UHI) on ozone concentrations in New York City. According to the data (Figures 5, 6, 11, and 12) it is determined that temperature and ozone concentration are directly related. However, this correlation is not always exact because other factors such as pressure and altitude also change ozone concentrations. From Figures 5 and 11 it is determined that altitude and ozone concentration are inversely related. From Figures 6 and 12 it is observed that ozone concentration is directly related to pressure. Although there are several factors related to ozone concentration the most significant is temperature. If we compare Figures 1 and 7, we see that in the New York City metropolitan area there was a significant increase in ozone concentration despite there being a temperature difference of only about 5⁰F. From this observation and our knowledge of urban heat islands a hypothesis was drawn that the New York City urban heat island will be a center for the growth of tropospheric ozone. However, when data regarding the temperatures in New York City and it’s surrounding areas was collected, it was observed that even though New York City is an urban heat island, its ozone concentrations were less than that of its surrounding areas. Looking at Figures 13 and 14 it is observed that while the low temperatures in New York City are higher than that of the surrounding areas, the high temperatures in New York City are often lower than that of the surrounding areas. While we are unsure of the reasons why, one theory we came up with was that the changes in temperature and ozone could be due to the fact that New York City is surrounded by water; therefore, in the summer it will be cooler than areas surrounded by land. It can be concluded that, although New York City is an urban heat island, this was not a major factor in the ozone concentration changes in New York City. To draw further conclusions and support our observations, soundings at the Brookhaven National Laboratory will continue to take place and surface ozone concentrations will continue to be observed.
Dr. Shermane Austin
Dr. Leon Johnson