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1. Global stratospheric effects of the alumina emissions by solid-fueled rocket motors

Author

Danilin, M. Y, Shia, R.-L., Ko, M. K. W, Weisenstein, D. K, Sze, N. D, Lamb, J. J, Smith, T. W, Lohn, P. D, and Prather, M. J

Subjects
size distribution, model, ozone, exhaust, impact, oxide, decomposition, simulations, particles
Abstract

We simulate accumulation of Al2O3 particles in the atmosphere produced by solid-fueled rocket motors by using the Goddard Institute for Space Studies/University of California at Irvine three-dimensional (3-D) chemistry-transport model (CTM). Our study differs from Jackman et al. (1998) by applying a 3-D CTM, considering 13 size bins for the emitted particles from 0.025 to 10 μm and taking into account their washout, gravitational sedimentation, and coagulation with background sulfate aerosol. We assume an initial trimodal size distribution of Al2O3 particles (Beiting, 1997) with 2.8% by mass of the alumina emitted as particles with radius of less than 1 μm. Our test case adopts a stratospheric source of 1120 tons/yr equivalent to nine space Shuttle and four Titan IV launches annually. The calculated steady state surface area density (SAD) and mass density for the scenarios with sedimentation of alumina particles have maximum values in the lower stratosphere in the Northern Hemisphere of up to 7×10−4 μm2/cm3 and 0.09 ng/m3, respectively, or about 1000 times smaller than those of the background sulfate aerosol. Our results are sensitive to the emitted mass fractionation of alumina (EMFA) showing the values for the SAD or mass density higher or lower by an order of magnitude owing to a poorly known EMFA. Chemical implications of alumina particle accumulation for the ozone balance are estimated by using the Atmospheric and Environmental Research 2-D model assuming chlorine activation on Al2O3 surfaces via the C1ONO2 + HCl → Cl2 + HNO3 reaction with a probability of 0.02 (Molina et al., 1997). Owing to the very small Al2O3 SAD, any additional ozone depletion due to Al2O3 emissions is also small (0.0028% on a global annually averaged basis for the scenario with sedimentation, or about 4 times smaller than the ozone response to chlorine emissions only). The ozone depletion potential of the alumina emissions is about 0.03–0.08 for the scenarios using the EMFA of Beiting (1997) and larger by an order of magnitude for the EMFA of Brady and Martin (1995).

Published
2001

2. Aviation fuel tracer simulation: Model intercomparison and implications

Author

Danilin, M. Y, Fahey, D. W, Schumann, U., Prather, M. J, Penner, J. E, Ko, M. K. W, Weisenstein, D. K, Jackman, C. H, Pitari, G., Kahler, I., Sausen, R., Weaver, C. J, Douglass, A. R, Connell, P. S, Kinnison, D. E, Dentener, F. J, Fleming, E. L, Berntsen, T. K, Isaksen, I. S. A, Haywood, J. M, and Karcher, B.

Subjects
aircraft, atmospheric aerosols, earth atmosphere, exhaust gases, gas emissions, mathematical models, soot, troposphere
Abstract

An upper limit for aircraft-produced perturbations to aerosols and gaseous exhaust products in the upper troposphere and lower stratosphere (UT/LS) is derived using the 1992 aviation fuel tracer simulation performed by eleven global atmospheric models. Key findings are that subsonic aircraft emissions: 1) have not be responsible for the observed water vapor trends at 40°N; 2) could be a significant source of soot mass near 12 km, but not at 20 km, 3) might cause a noticeable increase in the background sulfate aerosol surface area and number densities (but not mass density) near the northern mid-latitude tropopause, and 4) could provide a global, annual mean top of the atmosphere radiative forcing up to +0.006 W/m² and −0.013 W/m² due to emitted soot and sulfur, respectively.

Published
1998

4. Comparison of ER-2 Aircraft and POAM-III, MLS, and SAGE-II Satellite Measurements During SOLVE Using Traditional Correlative Analysis and Trajectory Hunting Technique

Author

Danilin, M. Y, Ko, Malcolm K. W, Bevilacqua, R. M, Lyjak, L. V, Froidevaux, L, Santee, M. L, Zawodny, J. M, Hoppel, K. W, Richard, E. C, Spackman, J. R, and Jackman, Charles H

Subjects
Geophysics
Abstract

We compared the version 5 Microwave Limb Sounder (MLS) aboard the Upper Atmosphere Research Satellite (UARS), version 3 Polar Ozone and Aerosol Measurement-III (POAM-111) aboard the French satellite SPOT-IV, version 6.0 Stratospheric Aerosol and Gas Experiment 11 (SAGE-II) aboard the Earth Radiation Budget Satellite, and NASA ER-2 aircraft measurements made in the northern hemisphere in January-February 2000 during the SAGE III Ozone Loss and Validation Experiment (SOLVE). This study addresses one of the key scientific objectives of the SOLVE campaign, namely, to validate multi-platform satellite measurements made in the polar stratosphere during winter. This intercomparison was performed using a traditional correlative analysis (TCA) and a trajectory hunting technique (THT). Launching backward and forward trajectories from the points of measurement, the THT identifies air parcels sampled at least twice within a prescribed match criterion during the course of 5 days. We found that the ozone measurements made by these four instruments agree most of the time within 110% in the stratosphere up to 1400 K (approximately 35 km). The water vapor measurements from POAM-III and the ER-2 Harvard Lyman-alpha hygrometer and JPL laser hygrometer agree to within 10.5 ppmv (or about +/-10%) in the lower stratosphere above 380 K. The MLS and ER-2 ClO measurements agree within their error bars for the TCA. The MLS and ER-2 nitric acid measurements near 17-20 km altitude agree within their uncertainties most of the time with a hint of a positive offset by MLS according to the TCA. We also applied the AER box model constrained by the ER-2 measurements for analysis of the ClO and HN03 measurements using the THT. We found that: (1) the model values of ClO are smaller by about 0.3-0.4 (0.2) ppbv below (above) 400 K than those by MLS and (2) the HN03 comparison shows a positive offset of MLS values by approximately 1 and 1-2 ppbv below 400 K and near 450 K, respectively. It is hard to quantify the HN03 offset in the 400-440 K range because of the high sensitivity of nitric acid to the PSC schemes. Our study shows that, with some limitations (like HN03 comparison under PSC conditions), the THT is a more powerful tool for validation studies than the TCA, making conclusions of the comparison statistically more robust.

Published
2001

6. Quantifying denitrification and its effects on ozone recovery

Author

Mergenthaler, J. L, Hamill, P. J, Newman, P. A, Pumphrey, H. C, Danilin, M. Y, Santee, M. L, and Tabazadeh, A

Abstract

Atmosphere Research Satellite observations indicate that extensive denitrification without significant dehydration currently occurs only in the Antarctic during mid to late June.

Published
2000

7. Trajectory Hunting: A Case Study of Rapid Chlorine Activation in December 1992 as Seen by UARS

Author

Danilin, M. Y, Santee, M. L, Rodriquez, J. M, Ko, M. K. W, Mergenthaler, J. M, Kumer, J. B, Tabazadeh, A, and Livesey

Subjects
Environment Pollution
Abstract

Trajectory hunting (i.e., a technique to find air parcels sampled at least twice over the course of a few days) is applied to analyze Upper Atmosphere Research Satellite (UARS) measurements in conjunction with the Atmospheric and Environmental Research, Inc. (AER) photochemical box model. As a case study, we investigate rapid chlorine activation in the Arctic lower stratosphere on December 29, 1992 associated with a polar stratospheric cloud (PSC) event. Eleven air parcels that have been sampled several times along 5-day trajectories at the 465 K (approx. 46 hPa), 520 K (approx. 31 hPa), and 585 K (approx. 22 hPa) levels were investigated. For the first time, the latest versions of the Cryogenic Limb Array Etalon Spectrometer (CLAES, version 9) and Microwave Limb Sounder (MLS, version 5) data sets are analyzed, and their consistency is assessed. A detailed sensitivity study with the AER photochemical box model along these trajectories leads to the conclusion that for the December 24-29, 1992 episode (1) the individual CLAES version 9 ClONO2 and MLS version 5 ClO measurements are self-consistent within their uncertainties; and (2) most of the time, UARS measurements of ClO, ClONO2, HNO3, and aerosol extinction at 780 cm (exp -1) agree within the range of their uncertainties with the model calculations. It appears that the HNO3 and aerosol extinction measurements for four parcels at 520 K look more supportive for the nitric acid trihydrate (NAT) scheme. However, the uncertainties in the individual UARS measurements and U.K. Meteorological Office temperature do not allow a definite discrimination between the NAT and supercooled ternary solution (STS) PSC schemes for this chlorine activation episode in December 1992.

Published
2000
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8. Utilization of UARS Data in Validation of Photochemical and Dynamical Mechanisms in Stratospheric Models

Author

Ko, M. K. W, Rodriquez, J. M, Hu, W, Danilin, M. Y, and Shia, R.-L

Subjects
Geophysics
Abstract

The proposed work utilized Upper Atmosphere Research Satellite (UARS) measurements of short-lived and long-lived species, in conjunction with existing photochemical "box" models, trajectory models, and two-dimensional global models, to elucidate outstanding questions in our understanding of photochemical and dynamical mechanisms in the stratosphere. Particular emphasis was given to arriving at the best possible understanding of the chemical and dynamical contributions to the stratospheric ozone budget. Such understanding will increase confidence in the simulations carried out by assessment models.

Published
1998

9. Nitrogen Species in the Post-Pinatubo Stratosphere: Model Analysis Utilizing UARS Measurements

Author

Danilin, M. Y, Rodriguez, J. M, Hu, W, Ko, M. K. W, Weisenstein, D. K, Kumer, J. B, Mergenthaler, J. L, Russell, J. M., III, Koike, M, and Yue, G. K

Subjects
Environment Pollution
Abstract

We present an analysis of the impact of heterogeneous chemistry on the partitioning of nitrogen species measured by the Upper Atmosphere Research Satellite (UARS) instruments. The UARS measurements utilized include: N2O, HNO3 and ClONO2 (Cryogen Limb Array Etalon Spectrometer (CLAES), version 7), temperature, methane, ozone, H2O, HCI, NO and NO2 (HALogen Occultation Experiment (HALOE), version 18). The analysis is carried out for the data from January 1992 to September 1994 in the 100-1 mbar (approximately 17-47 km) altitude range and over 10 degree latitude bins from 70 deg S to 70 deg N. Temporal-spatial evolution of aerosol surface area density (SAD) is adopted according to the Stratospheric Aerosol and Gas Experiment (SAGE) II data. A diurnal steady-state photochemical box model, constrained by the temperature, ozone, H2O, CH4, aerosol SAD and columns of O2 and O3 above the point of interest, has been used as the main tool to analyze these data. Total inorganic nitrogen (NOy) is obtained by three different methods: (1) as a sum of the UARS measured NO, NO2, HNO3, and CIONO2; (2) from the N2O-NOy correlation, (3) from the CH4-NOy correlation. To validate our current understanding of stratospheric heterogeneous chemistry for post-Pinatubo conditions, the model-calculated NOx/NOy ratios and the NO, NO2, and HNO3 profiles are compared to the UARS-derived data. In general, the UARS-constrained box model captures the main features of nitrogen species partitioning in the post-Pinatubo years. However, the model underestimates the NO2 content, particularly, in the 30-7 mbar (approximately 23-32 km) range. Comparisons of the calculated temporal behavior of the partial columns of NO2 and HNO3 and ground based measurements at 45 deg S and 45 deg N are also presented. Our analysis indicates that ground-based and HALOE v.18 measurements of the NO2 vertical columns are consistent within the range of their uncertainties and are systematically higher (up to 50%) than the model results at mid-latitudes in both hemispheres. Reasonable agreement is obtained for HNO3 columns at 45 deg S suggesting some problems with nitrogen species partitioning in the model. Outstanding uncertainties are discussed.

Published
1998

10. Trajectory Hunting: Analysis of UARS Measurements Showing Rapid Chlorine Activation

Author

Danilin, M. Y, Santee, M. L, Rodriquez, J. M, Ko, M. K. W, Mergenthaler, J. M, Kumer, J. B, and Tabazadeh, A

Subjects
Environment Pollution
Abstract

Trajectory hunting (i.e., a technique to find air parcels sampled at least twice over the course of a few days) is applied to analyze Upper Atmosphere Research Satellite (UARS) measurements in conjunction with the AER photochemical box model. In this study, we investigate rapid chlorine activation in the Arctic lower stratosphere on 29 Dec. 1992 associated with a polar stratospheric cloud (PSC) event. Six air parcels that have been sampled twice were followed along 5-day trajectories at the 465 K (approx. 46 mb) and 585 K (approxi. 22 mb) levels. A detailed sensitivity study with the AER photochemical box model along these trajectories leads to the following conclusions for the episode considered: 1) model results are in better agreement with UARS measurements at these levels if the U.K. Meteorological Office (UKMO) temperature is decreased by at least 1-2 K; 2) the NAT (nitric acid trihydrate) PSC formation scheme produces results in better agreement with observations than the STS (supercooled ternary solution) scheme; 3) the model can explain the UARS measurements at 585 K, but under-estimates the ClO abundance at 465 K, suggesting some inconsistency between the UARS measurements at this level.

Published
1998

11. Quantifying Denitrification and Its Effect on Ozone Recovery

Author

Tabzadeh, A., Santee, M. L., Danilin, M. Y., Pumphrey, H. C., Newman, P. A., Hamill, P. J., and Mergenthaler, J. L.

Subjects
Denitrification -- Research -- Environmental aspects, Ozone layer depletion -- Research -- Environmental aspects, Polar regions -- Environmental aspects -- Research, Science and technology, Research, Environmental aspects
Abstract

Upper Atmosphere Research Satellite observations indicate that extensive denitrification without significant dehydration currently occurs only in the Antarctic during mid to late June. The fact that denitrification occurs in a relatively warm month in the Antarctic raises concern about the likelihood of its occurrence and associated effects on ozone recovery in a colder and possibly more humid future Arctic lower stratosphere. Polar stratospheric cloud lifetimes required for Arctic denitrification to occur in the future are presented and contrasted against the current Antarctic cloud lifetimes. Model calculations show that widespread severe denitrification could enhance future Arctic ozone loss by up to 30%., Polar stratospheric clouds (PSCs) play important roles in the formation of the springtime Antarctic 'ozone hole' by activating chlorine and denitrifying the stratosphere (1-7). Although similar abundances of reactive chlorine [...]

Published
2000

12. Comparison of ER-2 aircraft and POAM III, MLS, and SAGE II satellite measurements during SOLVE using traditional correlative analysis and trajectory hunting technique

Author

Danilin, M. Y., Ko, M. K. W., Bevilacqua, R. M., Lyjak, L. V., Froidevaux, L., Santee, M. L., Zawodny, J. M., Hoppel, K. W., Richard, E. C., Spackman, J. R., Weinstock, E. M., Herman, R. L., McKinney, K. A., Wennberg, P. O., Eisele, F. L., Stimpfle, R. M., Scott, C. J., Elkins, J. W., and Bui, T. V.

Abstract

We compared the version 5 Microwave Limb Sounder (MLS), version 3 Polar Ozone and Aerosol Measurement III (POAM III), version 6.0 Stratospheric Aerosol and Gas Experiment II (SAGE II), and NASA ER-2 aircraft measurements made in the Northern Hemisphere in January–February 2000 during the SAGE III Ozone Loss and Validation Experiment (SOLVE). This study addresses one of the key scientific objectives of the SOLVE campaign, namely, to validate multiplatform satellite measurements made in the polar stratosphere during winter. This intercomparison was performed by using a traditional correlative analysis (TCA) and a trajectory hunting technique (THT). TCA compares profiles colocated within a chosen spatial-temporal vicinity. Launching backward and forward trajectories from the points of measurement, the THT identifies air parcels sampled at least twice within a prescribed match criterion during the course of 5 days. We found that the ozone measurements made by these four instruments agree most of the time within ±10% in the stratosphere up to 1400 K (∼35 km). The water vapor measurements from POAM III and the ER-2 Harvard Lyman α hygrometer and Jet Propulsion Laboratory laser hygrometer agree to within ±0.5 ppmv (or about ±10%) in the lower stratosphere above 380 K. The MLS and ER-2 ClO measurements agree within their error bars for the TCA. The MLS and ER-2 nitric acid measurements near 17- to 20-km altitude agree within their uncertainties most of the time with a hint of a positive offset by MLS according to the TCA. We also applied the Atmospheric and Environmental Research, Inc. box model constrained by the ER-2 measurements for analysis of the ClO and HNO3 measurements using the THT. We found that: (1) the model values of ClO are smaller by about 0.3–0.4 (0.2) ppbv below (above) 400 K than those by MLS and (2) the HNO3 comparison shows a positive offset of MLS values by ∼1 and 1–2 ppbv below 400 K and near 450 K, respectively. Our study shows that, with some limitations (like HNO3 comparison under polar stratospheric cloud conditions), the THT is a more powerful tool for validation studies than the TCA, making conclusions of the comparison statistically more robust.

Published
2002

13. Contribution to Chapter 3: Aviation-Produced Aerosols and Cloudiness

Author

Fahey, D. W., Schumann, U, Ackerman, S, Artaxo, P, Boucher, O, Danilin, M. Y., Karcher, B, Minnis, P, Nakajima, Toon, O. B., Ayers, J. K., Berntsen, T. K., Connell, P. S., Dentener, F. J., Doelling, D. R., Dopelheuer, A, Fleming, E. L., Gierens, K, Jackman, C. H., Jager, H, Jensen, E. J., Kent, G. S., Kohler, I, Meerkotter, R, Pitari, Giovanni, Prather, M. J., and Strom, J.

Published
1999

15. Quantifying uptake of HNO3 and H2O by alumina particles in Athena‐2 rocket plume

Author

Danilin, M. Y., primary, Popp, P. J., additional, Herman, R. L., additional, Ko, M. K. W., additional, Ross, M. N., additional, Kolb, C. E., additional, Fahey, D. W., additional, Avallone, L. M., additional, Toohey, D. W., additional, Ridley, B. A., additional, Schmid, O., additional, Wilson, J. C., additional, Baumgardner, D. G., additional, Friedl, R. R., additional, Thompson, T. L., additional, and Reeves, J. M., additional

Published
2003
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17. Trajectory hunting as an effective technique to validate multiplatform measurements: Analysis of the MLS, HALOE, SAGE‐II, ILAS, and POAM‐II data in October–November 1996

Author

Danilin, M. Y., primary, Ko, M. K. W., additional, Froidevaux, L., additional, Santee, M. L., additional, Lyjak, L. V., additional, Bevilacqua, R. M., additional, Zawodny, J. M., additional, Sasano, Y., additional, Irie, H., additional, Kondo, Y., additional, Russell, J. M., additional, Scott, C. J., additional, and Read, W. G., additional

Published
2002
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18. The emission and chemistry of reactive nitrogen species in the plume of an Athena II solid-fuel rocket motor

Author

Popp, P. J., primary, Ridley, B. A., additional, Neuman, J. A., additional, Avallone, L. M., additional, Toohey, D. W., additional, Zittel, P. F., additional, Schmid, O., additional, Herman, R. L., additional, Gao, R. S., additional, Northway, M. J., additional, Holecek, J. C., additional, Fahey, D. W., additional, Thompson, T. L., additional, Kelly, K. K., additional, Walega, J. G., additional, Grahek, F. E., additional, Wilson, J. C., additional, Ross, M. N., additional, and Danilin, M. Y., additional

Published
2002
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19. Comparison of ER‐2 aircraft and POAM III, MLS, and SAGE II satellite measurements during SOLVE using traditional correlative analysis and trajectory hunting technique

Author

Danilin, M. Y., primary, Ko, M. K. W., additional, Bevilacqua, R. M., additional, Lyjak, L. V., additional, Froidevaux, L., additional, Santee, M. L., additional, Zawodny, J. M., additional, Hoppel, K. W., additional, Richard, E. C., additional, Spackman, J. R., additional, Weinstock, E. M., additional, Herman, R. L., additional, McKinney, K. A., additional, Wennberg, P. O., additional, Eisele, F. L., additional, Stimpfle, R. M., additional, Scott, C. J., additional, Elkins, J. W., additional, and Bui, T. V., additional

Published
2002
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21. Observational evidence for the role of denitrification in Arctic stratospheric ozone loss

Author

Gao, R. S., primary, Richard, E. C., additional, Popp, P. J., additional, Toon, G. C., additional, Hurst, D. F., additional, Newman, P. A., additional, Holecek, J. C., additional, Northway, M. J., additional, Fahey, D. W., additional, Danilin, M. Y., additional, Sen, B., additional, Aikin, K., additional, Romashkin, P. A., additional, Elkins, J. W., additional, Webster, C. R., additional, Schauffler, S. M., additional, Greenblatt, J. B., additional, McElroy, C. T., additional, Lait, L. R., additional, Bui, T. P., additional, and Baumgardner, D., additional

Published
2001
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23. A comparison of Arctic HNO3profiles measured by the Improved Limb Atmospheric Spectrometer and balloon-borne sensors

Author

Koike, M., primary, Kondo, Y., additional, Irie, H., additional, Murcray, F. J., additional, Williams, J., additional, Fogal, P., additional, Blatherwick, R., additional, Camy-Peyret, C., additional, Payan, S., additional, Oelhaf, H., additional, Wetzel, G., additional, Traub, W., additional, Johnson, D., additional, Jucks, K., additional, Toon, G. C., additional, Sen, B., additional, Blavier, J.-F., additional, Schlager, H., additional, Ziereis, H., additional, Toriyama, N., additional, Danilin, M. Y., additional, Rodriguez, J. M., additional, Kanzawa, H., additional, and Sasano, Y., additional

Published
2000
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29. Canadian Middle Atmosphere Model: Preliminary Results from the Chemical Transport Module.

Author

De Grandpré, J., Sandilands, J. W., McConnell, J. C., Beagley, S. R., Croteau, P. C., and Danilin, M. Y.

Subjects
CLIMATOLOGY, MATHEMATICAL models, PERTURBATION theory, ATMOSPHERE, NITROGEN
Abstract

Copyright of Atmosphere - Ocean (Canadian Meteorological & Oceanographic Society) is the property of Canadian Meteorological & Oceanographic Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
1997

30. Validation of NO2and HNO3measurements from the Improved Limb Atmospheric Spectrometer (ILAS) with the version 5.20 retrieval algorithm

Author

Irie, H., Kondo, Y., Koike, M., Danilin, M. Y., Camy‐Peyret, C., Payan, S., Pommereau, J. P., Goutail, F., Oelhaf, H., Wetzel, G., Toon, G. C., Sen, B., Bevilacqua, R. M., Russell, J. M., Renard, J. B., Kanzawa, H., Nakajima, H., Yokota, T., Sugita, T., and Sasano, Y.

Abstract

The Improved Limb Atmospheric Spectrometer (ILAS) on board the Advanced Earth Observing Satellite (ADEOS) measured nitrogen dioxide (NO2) and nitric acid (HNO3) profiles from November 1996 to June 1997 at high latitudes in both hemispheres. The ILAS NO2profiles (version 5.20) are compared with those obtained by balloon‐borne and satellite measurements to validate ILAS NO2data. Comparisons with balloon‐borne measurements indicate that ILAS NO2at 25–30 km has a positive bias of 0.3–0.4 ppbv (6–11%). The random difference in NO2at 25–30 km is 0.2–0.3 ppbv (3–9%). The random error in the ILAS NO2measurements is larger than 100% below 20 km and above 45 km, where the NO2mixing ratios were less than 1.0 ppbv. It is possible that ILAS NO2values were lowered by optically thick aerosols with aerosol extinction coefficients at 780 nm of greater than 0.001 km−1. The lack of diurnal correction along the line of sight contributes to the positive bias in the ILAS NO2values below 25 km. Agreement of the ILAS NO2values with those by the Polar Ozone and Aerosol Measurement (POAM) II instrument is within 10–30% at 25–35 km. The agreement with the Halogen Occultation Experiment (HALOE) is as good as ±10% at 25–40 km. ILAS HNO3(version 5.20) agrees with balloon‐borne HNO3to within 0.1 ppbv (0–1%), and the random difference is within 10% at 25–30 km.

Published
2002
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