ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformatio... more ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show the technique is useful in the lower stratosphere at most latitudes throughout the year,and in the winter hemisphere in the middle stratosphere. The results are problematic in the summer hemisphere middle stratosphere due to increased ozone photochemistry and weak PV gradients. Alternate techniques in these regions will be discussed. An additional limitation is the quality and resolution of the meteorological data.
ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformatio... more ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show the technique is useful in the lower stratosphere at most latitudes throughout the year,and in the winter hemisphere in the middle stratosphere. The results are problematic in the summer hemisphere middle stratosphere due to increased ozone photochemistry and weak PV gradients. Alternate techniques in these regions will be discussed. An additional limitation is the quality and resolution of the meteorological data.
We have used ozone profile data from soundings for better interpretation of atmospheric chemistry... more We have used ozone profile data from soundings for better interpretation of atmospheric chemistry and dynamics at the urban-non-urban interface. Notably soundings have been taken during regional field campaigns like INTEX-NA (Intercontinental Transport Experiment - North America, 2004) and the 2006 Milagro/MIRAGE-Mex (Megacity Impacts of Regional and Global Environments)/ INTEX-B. IONS (INTEX Ozonesonde Network Study) is a network for studying the vertical structure and long-range transport of ozone and tropospheric water vapor during the INTEX experiments. In IONS-04, the urban-non-urban transition, was targeted at Beltsville, Maryland, a wooded suburban Washington DC site, and Narragansett, a coastal region downwind of New York City. From 5 to 20 March 2006, during IONS-06, ozone soundings were made over the Milagro T1 site (Tecamac, 19N, 99W), at the urban-rural interface, about 80 km NE of Mexico City. Simultaneous soundings were made over Houston, TX, 30N, 95W, approximately 1000 km to the northeast. Day-to-day variations in tropospheric ozone at T1 are explained by regional meteorology and emissions. Pollution accumulation at T1 was most noticeable during a stagnation period early in March, with winds from Mexico City. Downwind of T1, Houston was affected on 10 March 2006. In addition to pollution impacts, ozone variations throughout the troposphere and lower stratosphere over T1 were associated with equatorial Gravity waves. IONS-06 images for Mexico City/Tecamac, Houston, and those for other March 2006 data are viewable at: http://croc.gsfc.nasa.gov/intexb/ions06.
This study presents ozonesonde data from three sites: Valparaiso, IN, Pellston, MI, and Houston, ... more This study presents ozonesonde data from three sites: Valparaiso, IN, Pellston, MI, and Houston, TX. Sixteen launches occurred from the campus of Valparaiso University during the one-month period from 19 April through 16 May 2006. Thirty-six launches occurred from Pellston during the time period 1 July through 8 August 2004. These two data sets will comprise most of the analysis presented here. Data from Houston is used to compare ozone conditions in the boundary layer. Each flight consists of data with approximately one second resolution, ascent rates around 5 m/s, maximum altitudes between 20 and 30 km, and total flight times of about 2 hours. Only the lowest 3 km of the atmosphere were investigated in this study in order to concentrate on boundary layer conditions. The cut-off of 3 km was chosen since most boundary layer structure above normal vegetation in the mid-latitudes is below this level.
ABSTRACT The estimation of the precision of data from satellite instruments after launch has prov... more ABSTRACT The estimation of the precision of data from satellite instruments after launch has proved a difficult endeavor. Previous efforts to validate limb sounder data have relied upon nearby measurements from successive orbits that are separated in space by less than 100 km and in time by less than two hours. Such coincidences are rare for the typical satellite instrument and in the case of the Upper Atmosphere Research Satellite (UARS), only occur in two distinct latitude bands each month. An assessment of the overall, global precision of these data sets must rely upon an extrapolation of the results from these limited latitude bands in which coincidences occur and upon an analysis of the retrieval routines. This paper demonstrates the effectiveness of trajectory mapping in establishing instrument precision. Through application to water vapor data retrieved from approximately 22 - 40 km altitude by the microwave limb sounder (MLS) on UARS, we demonstrate that trajectory mapping provides a superior approach to post-launch evaluation of data precision. Unlike the traditional approach, trajectory mapping yields an estimate of precision for nearly every MLS water vapor measurement at all latitudes. In addition, in the limited latitude bands in which the traditional approach works, trajectory mapping estimates of precision are consistent with or slightly smaller than those found using the traditional approach in almost all cases. Sensitivity studies of the dependence of the trajectory mapping results on the direction and duration of the model integration, the correlation distance, the geographic location, and the season of the calculations help establish the uncertainties inherent in the technique as well as the conditions under which application of trajectory mapping is most appropriate.
ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformatio... more ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show the technique is useful in the lower stratosphere at most latitudes throughout the year,and in the winter hemisphere in the middle stratosphere. The results are problematic in the summer hemisphere middle stratosphere due to increased ozone photochemistry and weak PV gradients. Alternate techniques in these regions will be discussed. An additional limitation is the quality and resolution of the meteorological data.
ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformatio... more ABSTRACT In this study we utilize potential vorticity - isentropic (PVI) coordinate transformations as a means of combining ozone data from different sources to construct daily, synthetic three-dimensional ozone fields. This methodology has been used successfully to reconstruct ozone maps in particular regions from aircraft data over the period of the aircraft campaign. We expand this method to create high-resolution daily global maps of profile ozone data, particularly in the lower stratosphere, where high-resolution ozone data are sparse. Ozone climatologies in PVI-space are constructed from satellite-based SAGE II and UARS/HALOE data, both of which-use solar occultation techniques to make high vertical resolution ozone profile measurements, but with low spatial resolution. A climatology from ground-based balloonsonde data is also created. The climatologies are used to establish the relationship between ozone and dynamical variability, which is defined by the potential vorticity (in the form of equivalent latitude) and potential temperature fields. Once a PVI climatology has been created from data taken by one or more instruments, high-resolution daily profile ozone field estimates are constructed based solely on the PVI fields, which are available on a daily basis from NCEP analysis. These profile ozone maps could be used for a variety of applications, including use in conjunction with total ozone maps to create a daily tropospheric ozone product, as input to forecast models, or as a tool for validating independent ozone measurements when correlative data are not available. This technique is limited to regions where the ozone is a long-term tracer and the flow is adiabatic. We evaluate the internal consistency of the technique by transforming the ozone back to physical space and comparing to the original profiles. Biases in the long-term average of the differences are used to identify regions where the technique is consistently introducing errors. Initial results show the technique is useful in the lower stratosphere at most latitudes throughout the year,and in the winter hemisphere in the middle stratosphere. The results are problematic in the summer hemisphere middle stratosphere due to increased ozone photochemistry and weak PV gradients. Alternate techniques in these regions will be discussed. An additional limitation is the quality and resolution of the meteorological data.
We have used ozone profile data from soundings for better interpretation of atmospheric chemistry... more We have used ozone profile data from soundings for better interpretation of atmospheric chemistry and dynamics at the urban-non-urban interface. Notably soundings have been taken during regional field campaigns like INTEX-NA (Intercontinental Transport Experiment - North America, 2004) and the 2006 Milagro/MIRAGE-Mex (Megacity Impacts of Regional and Global Environments)/ INTEX-B. IONS (INTEX Ozonesonde Network Study) is a network for studying the vertical structure and long-range transport of ozone and tropospheric water vapor during the INTEX experiments. In IONS-04, the urban-non-urban transition, was targeted at Beltsville, Maryland, a wooded suburban Washington DC site, and Narragansett, a coastal region downwind of New York City. From 5 to 20 March 2006, during IONS-06, ozone soundings were made over the Milagro T1 site (Tecamac, 19N, 99W), at the urban-rural interface, about 80 km NE of Mexico City. Simultaneous soundings were made over Houston, TX, 30N, 95W, approximately 1000 km to the northeast. Day-to-day variations in tropospheric ozone at T1 are explained by regional meteorology and emissions. Pollution accumulation at T1 was most noticeable during a stagnation period early in March, with winds from Mexico City. Downwind of T1, Houston was affected on 10 March 2006. In addition to pollution impacts, ozone variations throughout the troposphere and lower stratosphere over T1 were associated with equatorial Gravity waves. IONS-06 images for Mexico City/Tecamac, Houston, and those for other March 2006 data are viewable at: http://croc.gsfc.nasa.gov/intexb/ions06.
This study presents ozonesonde data from three sites: Valparaiso, IN, Pellston, MI, and Houston, ... more This study presents ozonesonde data from three sites: Valparaiso, IN, Pellston, MI, and Houston, TX. Sixteen launches occurred from the campus of Valparaiso University during the one-month period from 19 April through 16 May 2006. Thirty-six launches occurred from Pellston during the time period 1 July through 8 August 2004. These two data sets will comprise most of the analysis presented here. Data from Houston is used to compare ozone conditions in the boundary layer. Each flight consists of data with approximately one second resolution, ascent rates around 5 m/s, maximum altitudes between 20 and 30 km, and total flight times of about 2 hours. Only the lowest 3 km of the atmosphere were investigated in this study in order to concentrate on boundary layer conditions. The cut-off of 3 km was chosen since most boundary layer structure above normal vegetation in the mid-latitudes is below this level.
ABSTRACT The estimation of the precision of data from satellite instruments after launch has prov... more ABSTRACT The estimation of the precision of data from satellite instruments after launch has proved a difficult endeavor. Previous efforts to validate limb sounder data have relied upon nearby measurements from successive orbits that are separated in space by less than 100 km and in time by less than two hours. Such coincidences are rare for the typical satellite instrument and in the case of the Upper Atmosphere Research Satellite (UARS), only occur in two distinct latitude bands each month. An assessment of the overall, global precision of these data sets must rely upon an extrapolation of the results from these limited latitude bands in which coincidences occur and upon an analysis of the retrieval routines. This paper demonstrates the effectiveness of trajectory mapping in establishing instrument precision. Through application to water vapor data retrieved from approximately 22 - 40 km altitude by the microwave limb sounder (MLS) on UARS, we demonstrate that trajectory mapping provides a superior approach to post-launch evaluation of data precision. Unlike the traditional approach, trajectory mapping yields an estimate of precision for nearly every MLS water vapor measurement at all latitudes. In addition, in the limited latitude bands in which the traditional approach works, trajectory mapping estimates of precision are consistent with or slightly smaller than those found using the traditional approach in almost all cases. Sensitivity studies of the dependence of the trajectory mapping results on the direction and duration of the model integration, the correlation distance, the geographic location, and the season of the calculations help establish the uncertainties inherent in the technique as well as the conditions under which application of trajectory mapping is most appropriate.
Uploads
Papers by Gary Morris