Pasadena, California, Data

Evaluation of Alternative Forms of the Ozone Air Quality Standard with 1971 Pasadena, California, Data Earlier, 1971 hourly average and maximum daily hourly average ozone mixing ratios at Pasadena, California, were fit to Weibull distributions. We now wish to evaluate the four forms of the ozone air quality standard with these data. For convenience all mixing ratios values will be given as pphm rather than ppm. 

Evaluation of Alternative Forms of the Ozone Air Quality Standard with 1971 Pasadena, California, Data... 

Howard, C., Ravishankara, A., Kolb, C., and Molina, M. Chemical Kinetics and Photochemical Data for Use in Stratospheric Modeling Evaluation 11, Jet Propulsion Laboratory, Pasadena, California, USA, 1994. 

FIGURE 3-2S Diurnal profiles of nitrogen compounds, Pasadena, California, July 25, 1974. NO, NO, O, and PAN in ppm inorganic aerosol nitrates in Mg/m Data from Grosjean and Friedlander and Hanst et o/. ... 

There are several highly useful sources of data on the absorption spectra and photochemistry of atmospheric species. NASA publishes on a regular basis a summary of kinetics and photochemical data directed to stratospheric chemistry (DeMore et al., 1997). However, much of the data is also relevant to the troposphere. This document can be obtained from the Jet Propulsion Laboratory in Pasadena, California. Alternatively, the data are available through the Internet (see Appendix IV). IUPAC also publishes regularly in The Journal of Physical Chemical Reference Data a summary directed more toward tropospheric chemistry (Atkinson et al., 1997a, 1997b). Finally, Nolle et al. (1999) have made available a CD-ROM containing the UV-visible spectra of species of atmospheric interest. 

The problem arose because two teams working on the Mars mission were using different sets of units. NASA s scientists at the Jet Propulsion Laboratory in Pasadena, California, assumed that the thrust data for the rockets on the Orbiter they received from Lockheed Martin Astronautics in Denver, which built the spacecraft, were in metric units. In reality, the units were English. As a result the Orbiter dipped 100 kilometers lower into the Mars atmosphere than planned and the friction from the atmosphere caused the craft to burn up. 

DeMore, W. B., J. J. Margitan, M. J. Molina, R. T. Watson, R. F. Hampson, M. J. Kurylo, D. M. Golden, C. J. Howard, and A. R. Ravishankara (1985). Chemical kinetics and photochemical data for use in stratospheric modeling, evaluation number 7. National Aeronautics and Space Administration, California Jet Propulsion Laboratory, Publication 85-37. Institute of Technology, Pasadena, California. 

As an example, we consider the fitting of a Weibull distribution to 1971 hourly average ozone data from Pasadena, California. The data consist of 8303 hourly values (there are 8760 h in a year). The maximum hourly value reported was 53 parts-per-hundred million (pphm). The arithmetic mean and standard deviation of the data are M = 4.0 pphm and M2 2 = 5.0 pphm, and the geometric mean and geometric standard deviation are 2.4 and 2.6 pphm, respectively. If one assumes that the hourly average ozone mixing ratios fit a Weibull distribution, the parameters of the distribution can be estimated from (26.51) and (26.52) to give X = 0.808 and a = 3.555 pphm. 

TABLE 26.8 1971 Hourly Average Pasadena, California, Ozone Data Fitted to a Weibull Distribution... 

The expected number of exceedances of 12 pphm, based on the Weibull fit of the 1971 Pasadena, California, hourly average data, is, from (26.64)... 

TABLE 26.P.1 Carbon Monoxide Concentrations at Pasadena, California, for 1982 Some Statistics of 1 Hour Average Data, ppm... 

As an example, we consider the fitting of a Weibull distribution to 1971 hourly average ozone data from Pasadena, California. The data consist of 8303 hourly values (there are 8760 hours in a year). The maximum hourly mean and standard deviation of the data... 

A variety of techniques to identify and quantify acid and base components in rainwater are applied to data for southern California. Charge balance calculations using major cation and anion concentration data indicate southern California probably had alkaline rain in the 1950 s and the 1960 s with the exception of the Los Angeles area which probably had acidic precipitation. Measurements of the chemical composition of precipitation collected in Pasadena, California, from February 1976 to September 1977 are compared with the charge balance and conductivity balance constraints. A chemical balance is used to determine the relative importances of different sources. The pH is found to be controlled by the interaction of bases and strong acids with nitric acid being 32% more important on an equivalent basis than sulfuric acid. The uncertainties in the various calculations are discussed. 

Why do scientists wony about units The National Aeronautics and Space Administration (NASA) recently was reminded of just why keeping track of units is so important. In 1999 a 125 million satellite was lost in the atmosphere of Mars because scientists made some improper assumptions about units. NASA s scientists at the Jet Propulsion Lab (JPL) in Pasadena, California, received thrust data from the satellite s manufacturer, Lockheed Martin Aeronautics in Denver, Colorado. Unfortunately, the Denver scientists used American units in their measurements and the JPL scientists assumed the units were metric. This mistake caused the sateUite to fall 100 km lower into the Mars atmosphere than planned. The spacecraft burned up from the friction with the atmosphere. 

Peterson, J.T. Calculated Actinic Fluxes (290-700 nm) fm Air Pollution Photochemistry Applications. U.S. Environmental Protection Agency report no. EPA-600/4-76-025, June (1976) Sander, S.P., Baker, R., Golden, D.M., Kurylo, M.J., Wine, P.H., Abatt, J.P.D., Burkholder, J.B., Kolb, C.E., Moortgat, G.K., Huie, R.E., Orkin, V.L. Chemical Kinetics and Photochemical Data for Use in Atmospheric Studies, Evaluation Number 17, JPL Publication 10-6, Pasadena, California. Website http //jpldataeval.jpl.nasa.gov/(2011)... 

FIGURE 4-22 Number of days in 1973 on which the maximal hourly average oxidant concentration equaled or exceeded 0.20 ppm at six air monitoring stations in the southern California coast air basin. Data as reported Los Angeles, Pasadena, Pomona, and Azusa reported by Los Angeles County apcd Riverside reported by Riverside County apcd and San Bernardino reported by San Bernardino County APCD. Reprinted with permission from Ktts. ... 

Fig. 6.8. Log-log plot of Wrap versus electrolyte concentration for hematite ( Fe203) colloids suspended in either CaCl2 or NaCI solution at pH 10.5. Arrows indicate critical coagulation concentrations [Eq. 6.76 data from L Liang, Effects of surface chemistry on kinetics of coagulation of submicron iron oxide particles (a-Fe2Oi) in water, Ph.D. dissertation, California Institute of Technology, Pasadena, CA, 1988. Environmental Quality Laboratory Report No. AC-5-88].

S.P. Sander, et ah. Chemical kinetics and photochemical data for use in atmospheric studies Evaluation number 15, in JPL Publication 0 02, 2006, Jet Propulsion Laboratory, California Institute of Technology Pasadena, CA. 

W. B. DeMore. S.P. Sander, D.M. Golden, R.F. Hampson,M.J. Kurylo. C.J. Howard, A.R. Ravishankara, C.E. Kolb, M.,1. Molina, ChemicalKinetics and Photochemical Data for Use in Stratospheric Modeling. Evaluation No. ii,IPL Publ. 94-26 NASA Panel for Data Evaluation, Jet PropulsionLaboratory, (California Institute of Technology, Pasadena. 1994) p. 194. 

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