Formation of the ozone layer. [Modified from Jacob 10.1] Consider a beam of solar radiation of...

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Formation of the ozone layer. [Modified from Jacob 10.1] Consider a beam of solar radiation of wavelength λ propagating downward in the vertical direction with an actinic flux l.. at the top of the atmosphere. Assume that O₂ is the sole atmospheric absorber of this radiation. The expression for the dependence of the O₂ photolysis rate R from this radiation beam with altitude z, in terms of o the absorption cross-section for O2 at wavelength X, q the corresponding quantum yield for O₂ photolysis, na(z) the air density, H the scale height of the atmosphere, and Co2 the O₂ mole fraction, assuming CO₂, q, and o are constant with z, is given by (where na(z)=n₂(0)exp[-z/H]): R(z) qo Co₂ na (0) Ioo exp[-- Co₂ H na (2)] Use the Google Sheet with the ISA standard atmosphere provided in class and H=7.4km to do the following: A. Make plots of T(z), I(z), and na(z) (on the x-axis) versus z (on the y-axis) for the lowest 100 km of the atmosphere (also called the "homosphere") using the ISA standard atmosphere. Then make two plots of R(z): (i) using na(z) from ISA and (ii) using na(z)=na(0)exp(-z/H). Be sure to label the curves and axes. Note that the expression above for R(z) is for the scale height model, if you replace na(z) with na(z)=na(0)exp(-z/H). For using the ISA model, it is fine to still use the scale height approach to simplify the value of optical depth but do not use scale height in simplifying n₂(z). The expression for each is given in the Sheet provided in class so that you can make sure you are using the formula correctly. B. Give the z locations of maximum values of T, I, na, and R in the range plotted (some maxima will be end points). Be sure to include Zmax for cases (i) and (ii) for the maximum of R(z) and to comment on any differences. = C. Do you expect that T(z) will affect na(z)? If so, specify how they are related. D. How do na(z) and I(z) affect R(z)? Specify which of these two factors drives increases in R(z) above and below the maximum in R(z). Why is the maximum in R(z) not at the same altitude as the maximum in na(z)? E. Does R(z) affect T(z)? If so, think about why this may be and describe the underlying process that is most relevant to this chapter (but uses some knowledge from Chapter 7 about what happens when gases absorb energy). Formation of the ozone layer. [Modified from Jacob 10.1] Consider a beam of solar radiation of wavelength λ propagating downward in the vertical direction with an actinic flux l.. at the top of the atmosphere. Assume that O₂ is the sole atmospheric absorber of this radiation. The expression for the dependence of the O₂ photolysis rate R from this radiation beam with altitude z, in terms of o the absorption cross-section for O2 at wavelength X, q the corresponding quantum yield for O₂ photolysis, na(z) the air density, H the scale height of the atmosphere, and Co2 the O₂ mole fraction, assuming CO₂, q, and o are constant with z, is given by (where na(z)=n₂(0)exp[-z/H]): R(z) qo Co₂ na (0) Ioo exp[-- Co₂ H na (2)] Use the Google Sheet with the ISA standard atmosphere provided in class and H=7.4km to do the following: A. Make plots of T(z), I(z), and na(z) (on the x-axis) versus z (on the y-axis) for the lowest 100 km of the atmosphere (also called the "homosphere") using the ISA standard atmosphere. Then make two plots of R(z): (i) using na(z) from ISA and (ii) using na(z)=na(0)exp(-z/H). Be sure to label the curves and axes. Note that the expression above for R(z) is for the scale height model, if you replace na(z) with na(z)=na(0)exp(-z/H). For using the ISA model, it is fine to still use the scale height approach to simplify the value of optical depth but do not use scale height in simplifying n₂(z). The expression for each is given in the Sheet provided in class so that you can make sure you are using the formula correctly. B. Give the z locations of maximum values of T, I, na, and R in the range plotted (some maxima will be end points). Be sure to include Zmax for cases (i) and (ii) for the maximum of R(z) and to comment on any differences. = C. Do you expect that T(z) will affect na(z)? If so, specify how they are related. D. How do na(z) and I(z) affect R(z)? Specify which of these two factors drives increases in R(z) above and below the maximum in R(z). Why is the maximum in R(z) not at the same altitude as the maximum in na(z)? E. Does R(z) affect T(z)? If so, think about why this may be and describe the underlying process that is most relevant to this chapter (but uses some knowledge from Chapter 7 about what happens when gases absorb energy).

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A Plotting Tz Iz and naz vs z Using the provided Google Sheet and the ISA standard atmosphere I have plotted the following 1 Temperature Tz vs altitude z The temperature decreases with increasing alti... View the full answer