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Jack Fishman - One of the best experts on this subject based on the ideXlab platform.
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Observing Tropospheric Ozone From Space
2020Co-Authors: Jack FishmanAbstract:The importance of Tropospheric Ozone embraces a spectrum of relevant scientific issues ranging from local environlnental concerns, such as damage to the biosphere and human health, to those that impact global change questions, such as climate warming. From an obser- vational perspective, the challenge is to determine the Tropospheric Ozone global distribution. Because its lifetime is short compared with other important greenhouse gases that have been monitored over the past several decades, the distribution of Tropospheric Ozone cannot be inferred from a relatively small set of monitoring stations. Therefore, the best way to obtain a true global picture is from the use of space-based instrumentation where important spatial gradients over vast ocean expanses and other uninhabited areas can be properly characterized. )n this paper, the development of the capability to measure Tropospheric Ozone from space over the past 15 years is summarized. Research in the )ate 19g0s successfully led to the determination of the climatology of Tropospheric Ozone as a function of season; more recently, the methodology has improved to the extent where regional air pollution episodes can be characterized. The most recent modifications now provide quasi-global (50°N to 50:5) maps on a daily basis. Such a data set would allow for the study of long-range (intercontinental) transport of air pollution and the quantification of how regional emissions feed into the global Tropospheric Ozone budget. Future nleasurement capabilities within this decade promise to offer the ability to provide concurrent maps of the precursors to the i_7situ formation of Tropospheric Ozone, from which the scientific community will gain unprecedented insight into the processes that control global Tropospheric chemistry.
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Intercontinental transport of Tropospheric Ozone: a study of its seasonal variability across the North Atlantic utilizing Tropospheric Ozone residuals and its relationship to the North Atlantic Oscillation
Atmospheric Chemistry and Physics, 2003Co-Authors: John K. Creilson, Jack Fishman, Amy E. WozniakAbstract:Abstract. Using the empirically-corrected Tropospheric Ozone residual (TOR) technique, which utilizes coincident observations of total Ozone from the Total Ozone Mapping Spectrometer (TOMS) and stratospheric Ozone profiles from the Solar Backscattered Ultraviolet (SBUV) instruments, the seasonal and regional distribution of Tropospheric Ozone across the North Atlantic from 1979-2000 is examined. Its relationship to the North Atlantic Oscillation (NAO) is also analyzed as a possible transport mechanism across the North Atlantic. Monthly climatologies of Tropospheric Ozone for five different regions across the North Atlantic exhibit strong seasonality. The correlation between these monthly climatologies of the TOR and Ozonesonde profiles at nearby sites in both eastern North America and western Europe are highly significant (R values of +0.98 and +0.96 respectively) and help to validate the use of satellite retrievals of Tropospheric Ozone. Distinct springtime interannual variability over North Atlantic Region 5 (eastern North Atlantic-western Europe) is particularly evident and exhibits similar variability to the positive phase of the NAO (R=+0.61, r =
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global distribution of Tropospheric Ozone from satellite measurements using the empirically corrected Tropospheric Ozone residual technique identification of the regional aspects of air pollution
Atmospheric Chemistry and Physics, 2003Co-Authors: Jack Fishman, John K. Creilson, Amy E. WozniakAbstract:Using coincident observations of total Ozone from the Total Ozone Mapping Spectrometer (TOMS) and strato- spheric Ozone profiles from the Solar Backscattered Ultra- violet (SBUV) instruments, detailed maps of Tropospheric Ozone have been derived on a daily basis over a time period spanning more than two decades. The resultant climatolog- ical seasonal depictions of the Tropospheric Ozone residual (TOR) show much more detail than an earlier analysis that had used coincident TOMS and Stratospheric Aerosol and Gas Experiment (SAGE) Ozone profiles, although there are many similarities between the TOMS/SAGE TOR and the TOMS/SBUV TOR climatologies. In particular, both TOR seasonal depictions show large enhancements in the south- ern tropics and subtropics in austral spring and at northern temperate latitudes during the summer. The much greater detail in this new data set clearly defines the regional aspect of Tropospheric Ozone pollution in northeastern India, eastern United States, eastern China, and west and southern Africa. Being able to define monthly climatologies for each year of the data record provides enough temporal resolution to illus- trate significant interannual variability in some of these re- gions.
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Tests of a compact lidar system for global monitoring of Tropospheric Ozone
Proceedings of SPIE, 1999Co-Authors: Thomas H. Chyba, J. Thomas Zenker, Renee Payne-baggott, Crystal Toppin, Mika Edmondson, Kyle Lewis, David Harper, N. S. Higdon, Dale A. Richter, Jack FishmanAbstract:The need for high resolution spatial and temporal measurements of Tropospheric Ozone is discussed. Tropospheric Ozone is globally increasing due to anthropogenic sources such as industrialization and biomass burning. In addition to its hazardous effects during pollution episodes, elevated levels of Tropospheric Ozone may have additional detrimental environmental effects due to Ozone's crucial role in Tropospheric chemistry and in global climate. Ground-based lidar instruments can play an important role in meeting this measurement need. We present test results for a prototype compact, minimal-cost Ozone lidar. The instrument is designed to be as reliable and simple as possible but still be capable of routinely measuring Ozone profiles with less than 10% relative error from the ground up into the lower stratosphere. In addition to local pollution monitoring, this lidar satisfies the basic requirements necessary for future global monitoring projects requiring multi-instrument networks, such as that proposed for the Global Tropospheric Ozone Project (GTOP). GTOP is currently being formulated by a scientific panel of the International Global Atmospheric Chemistry Project to meet its goal to better understand the processes that control the global sources, sinks, and transformation mechanisms of Tropospheric Ozone.
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A 5-year evaluation of the representativeness of the Tropospheric Ozone residual at nonclimatological periods
Journal of Geophysical Research, 1997Co-Authors: Fred M. Vukovich, Jack Fishman, Vincent G. Brackett, Joseph E. SicklesAbstract:Daily values, monthly averages, and seasonal averages of the Tropospheric Ozone residual (TOR) were estimated using the Total Ozone Mapping Spectrometer (TOMS) and the Solar Backscattered Ultraviolet (SBUV) data for the five-year period 1985–1989. Comparisons were made at these various timescales between TOR and Tropospheric Ozone using data from eight Ozonesonde stations within the region 50°N to 50°S and between normalized departures of the TOR and surface Ozone data averaged over four 5° latitude by 5° longitude squares within the eastern United States. These comparisons were accomplished to determine the usefulness of the TOR to represent Tropospheric Ozone at nonclimatological periods. The results indicated that the annual cycle of the TOR determined using monthly and seasonally averaged values provides a realistic depiction of the annual cycle of Tropospheric Ozone in the northern hemisphere; that is, approximately a 2% mean error and an 81% correlation. However, in a limited number of comparisons (Hilo and Natal), the annual cycle of the TOR represented the annual cycle of Tropospheric Ozone at tropical latitudes poorly; that is, approximately a 38% mean error and a 59% correlation.
B. J. Johnson - One of the best experts on this subject based on the ideXlab platform.
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long term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of � 20 years in length agree in showing increases that are strongest in the austral spring (August–October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years.
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Long-term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of ∼20 years in length agree in showing increases that are strongest in the austral spring (August-October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years. In the N.H. tropics both the surface record and the Ozonesondes in Hawaii show a significant increase in the autumn months in the most recent decade compared to earlier periods that drives the overall increase seen in the 30-year record. This appears to be related to a shift in the transport pattern during this season with more frequent flow from higher latitudes in the latest decade. © 2006 Elsevier Ltd. All rights reserved.
D. Tarasick - One of the best experts on this subject based on the ideXlab platform.
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A global Tropospheric Ozone climatology from trajectory-mapped Ozone soundings
Atmospheric Chemistry and Physics Discussions, 2013Co-Authors: D. Tarasick, V. E. Fioletov, O. Moeni, C. E. SiorisAbstract:Abstract. A global three-dimensional (i.e. latitude, longitude, altitude) climatology of Tropospheric Ozone is derived from the Ozone sounding record by trajectory mapping. Approximately 52 000 Ozonesonde profiles from more than 100 stations worldwide since 1962 are used. The small number of stations causes the set of Ozone soundings to be sparse in geographical spacing. Here, forward and backward trajectory calculations are performed for each sounding to map Ozone measurements to a number of other locations, and so to fill in the spatial domain. This is possible because the lifetime of Ozone in the troposphere is of the order of weeks. This physically-based interpolation method offers obvious advantages over typical statistical interpolation methods. The trajectory-mapped Ozone values show reasonable agreement, where they overlap, to the actual soundings, and the patterns produced separately by forward and backward trajectory calculations are similar. Major regional features of the Tropospheric Ozone distribution are clearly evident in the global maps. An interpolation algorithm based on spherical functions is further used for smoothing and to fill in remaining data gaps. The resulting three-dimensional global Tropospheric Ozone climatology facilitates visualization and comparison of different years, decades, and seasons, and offers some intriguing insights into the global variation of Tropospheric Ozone. It will be useful for climate and air quality model initialization and validation, and as an a priori climatology for satellite data retrievals. Further division of the climatology into decadal averages provides a global view of Tropospheric Ozone trends, which appear to be surprisingly modest over the last four decades.
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long term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of � 20 years in length agree in showing increases that are strongest in the austral spring (August–October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years.
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Long-term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of ∼20 years in length agree in showing increases that are strongest in the austral spring (August-October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years. In the N.H. tropics both the surface record and the Ozonesondes in Hawaii show a significant increase in the autumn months in the most recent decade compared to earlier periods that drives the overall increase seen in the 30-year record. This appears to be related to a shift in the transport pattern during this season with more frequent flow from higher latitudes in the latest decade. © 2006 Elsevier Ltd. All rights reserved.
John K. Creilson - One of the best experts on this subject based on the ideXlab platform.
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Intercontinental transport of Tropospheric Ozone: a study of its seasonal variability across the North Atlantic utilizing Tropospheric Ozone residuals and its relationship to the North Atlantic Oscillation
Atmospheric Chemistry and Physics, 2003Co-Authors: John K. Creilson, Jack Fishman, Amy E. WozniakAbstract:Abstract. Using the empirically-corrected Tropospheric Ozone residual (TOR) technique, which utilizes coincident observations of total Ozone from the Total Ozone Mapping Spectrometer (TOMS) and stratospheric Ozone profiles from the Solar Backscattered Ultraviolet (SBUV) instruments, the seasonal and regional distribution of Tropospheric Ozone across the North Atlantic from 1979-2000 is examined. Its relationship to the North Atlantic Oscillation (NAO) is also analyzed as a possible transport mechanism across the North Atlantic. Monthly climatologies of Tropospheric Ozone for five different regions across the North Atlantic exhibit strong seasonality. The correlation between these monthly climatologies of the TOR and Ozonesonde profiles at nearby sites in both eastern North America and western Europe are highly significant (R values of +0.98 and +0.96 respectively) and help to validate the use of satellite retrievals of Tropospheric Ozone. Distinct springtime interannual variability over North Atlantic Region 5 (eastern North Atlantic-western Europe) is particularly evident and exhibits similar variability to the positive phase of the NAO (R=+0.61, r =
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global distribution of Tropospheric Ozone from satellite measurements using the empirically corrected Tropospheric Ozone residual technique identification of the regional aspects of air pollution
Atmospheric Chemistry and Physics, 2003Co-Authors: Jack Fishman, John K. Creilson, Amy E. WozniakAbstract:Using coincident observations of total Ozone from the Total Ozone Mapping Spectrometer (TOMS) and strato- spheric Ozone profiles from the Solar Backscattered Ultra- violet (SBUV) instruments, detailed maps of Tropospheric Ozone have been derived on a daily basis over a time period spanning more than two decades. The resultant climatolog- ical seasonal depictions of the Tropospheric Ozone residual (TOR) show much more detail than an earlier analysis that had used coincident TOMS and Stratospheric Aerosol and Gas Experiment (SAGE) Ozone profiles, although there are many similarities between the TOMS/SAGE TOR and the TOMS/SBUV TOR climatologies. In particular, both TOR seasonal depictions show large enhancements in the south- ern tropics and subtropics in austral spring and at northern temperate latitudes during the summer. The much greater detail in this new data set clearly defines the regional aspect of Tropospheric Ozone pollution in northeastern India, eastern United States, eastern China, and west and southern Africa. Being able to define monthly climatologies for each year of the data record provides enough temporal resolution to illus- trate significant interannual variability in some of these re- gions.
Samuel J. Oltmans - One of the best experts on this subject based on the ideXlab platform.
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long term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of � 20 years in length agree in showing increases that are strongest in the austral spring (August–October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years.
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Long-term changes in Tropospheric Ozone
Atmospheric Environment, 2006Co-Authors: Samuel J. Oltmans, A. S. Lefohn, I. Galbally, H. E. Scheel, E. Brunke, D. Tarasick, Gregory Bodeker, Hans Claude, J.m. Harris, B. J. JohnsonAbstract:Tropospheric Ozone changes are investigated using a selected network of surface and Ozonesonde sites to give a broad geographic picture of long-term variations. The picture of long-term Tropospheric Ozone changes is a varied one in terms of both the sign and magnitude of trends and in the possible causes for the changes. At mid latitudes of the S.H. three time series of ∼20 years in length agree in showing increases that are strongest in the austral spring (August-October). Profile measurements show this increase extending through the mid troposphere but not into the highest levels of the troposphere. In the N.H. in the Arctic a period of declining Ozone in the troposphere through the 1980s into the mid-1990s has reversed and the overall change is small. The decadal-scale variations in the troposphere in this region are related in part to changes in the lowermost stratosphere. At mid latitudes in the N.H., continental Europe and Japan showed significant increases in the 1970s and 1980s. Over North America rises in the 1970s are less than those seen in Europe and Japan, suggesting significant regional differences. In all three of these mid latitude, continental regions Tropospheric Ozone amounts appear to have leveled off or in some cases declined in the more recent decades. Over the North Atlantic three widely separated sites show significant increases since the late-1990s that may have peaked in recent years. In the N.H. tropics both the surface record and the Ozonesondes in Hawaii show a significant increase in the autumn months in the most recent decade compared to earlier periods that drives the overall increase seen in the 30-year record. This appears to be related to a shift in the transport pattern during this season with more frequent flow from higher latitudes in the latest decade. © 2006 Elsevier Ltd. All rights reserved.
