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Papers by Pawan Bhartia
Geophysical Research Letters, 1988
Using techniques very similar to those used in comparing SBUV total ozone with Dobson [Fleig et a... more Using techniques very similar to those used in comparing SBUV total ozone with Dobson [Fleig et al. 1986A], seven years of total ozone data derived from the TOMS instrument on Nimbus‐7 are compared with results from 41 Dobson stations. In this study however, a ...
Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus ... more Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus 7 were archived at the National Space Science Data Center. The experiment measures the fraction of incoming radiation backscattered by the Earth's atmosphere at 12 wavelengths. In-flight measurements were used to monitor changes in the instrument sensitivity. Total column ozone is derived by comparing the measurements with calculations of what would be measured for different total ozone amounts. The altitude distribution is retrieved using an optimum statistical technique for the inversion. The estimated initial error in the absolute scale for total ozone is 2 percent, with a 3 percent drift over 8 years. The profile error depends on latitude and height, smallest at 3 to 10 mbar; the drift increases with increasing altitude. Three tape products are described. The High Density SBUV (HDSBUV) tape contains the final derived products - the total ozone and the vertical ozone profile - as ...
Journal of Geophysical Research, 2003
IEEE Transactions on Geoscience and Remote Sensing, 2013
Journal of Geophysical Research, 2003
IEEE Transactions on Geoscience and Remote Sensing, 2006
IEEE Transactions on Geoscience and Remote Sensing, 2006
IEEE Transactions on Geoscience and Remote Sensing, 2006
Advances in Space Research, 1982
... REFERENCES 1. GHB Dobson and DN Harrison, Proc. Roy. Soc., Ser. A 110, 660 (1926) 2. FE Fowle... more ... REFERENCES 1. GHB Dobson and DN Harrison, Proc. Roy. Soc., Ser. A 110, 660 (1926) 2. FE Fowle, Smithsonian Miscellaneous Collections 81, 1 (1929) 3. GM Keating, L. Frank, JD Craven, D. Young, J. Nicholson, P. Bhartia, D. Gordon, EOS, Trans. ...
IEEE Transactions on Geoscience and Remote Sensing, 2006
<p>The NASA TOMS V9 (TOMS-V9) total ozone retrieval algorithm is tested<br>for sensit... more <p>The NASA TOMS V9 (TOMS-V9) total ozone retrieval algorithm is tested<br>for sensitvity to boundary-layer ozone and suitability to make daily<br>maps of tropospheric ozone residual (TOR).  Daily maps of TOR are<br>derived by differencing co-located MERRA-2 assimilated MLS<br>stratospheric column ozone (SCO) from total column ozone from the Aura<br>Ozone Monitoring Instrument (OMI).  The TOMS-V9 algorithm uses a few<br>discrete channels with an order of magnitude range in ozone<br>senstivity. We compare the TOR results from TOMS-V9 with results from<br>several hyper-spectral total ozone retrievals: GODFIT v4 (BIRA-IASB),<br>OMI-DOAS (KNMI), and total ozone from the SAO PROFOZ algorithm. We<br>compare all satellite-retrieved TOR with TOR derived from ozonesondes,<br>lidar, and the Goddard Modeling Initiative (GMI) model simulation.</p><p> </p><p> </p>
An assessment of OMI retrievals of aerosol properties is presented. We compare OMI retrieved valu... more An assessment of OMI retrievals of aerosol properties is presented. We compare OMI retrieved values of extinction and absorption optical depth, and aerosol single scattering albedo to AERONET ground-based measurements. An evaluation of the accuracy of the retrievals for a limited number of observations under cloud-free conditions shows a positive offset of about 0.03 in retrieved optical depth. This small offset is an indication of accurate sensor calibration to the 1% level. The retrieved SSA values agree well with RMS differences of 0.02-0.03 compared with the AERONET observations. This result shows that the UV technique is a very valuable tool for measuring aerosol absorption from space.
We discuss collection 2 SO2 data from the Dutch-Finnish Ozone Monitoring Instrument (OMI) on boar... more We discuss collection 2 SO2 data from the Dutch-Finnish Ozone Monitoring Instrument (OMI) on board NASA EOS/Aura spacecraft and show examples of detected volcanic and anthropogenic SO2 emissions. Quantification of anthropogenic SO2 emissions requires collection 3 reprocessing available in the fall 2007.
Geophysical Research Letters, 1988
Using techniques very similar to those used in comparing SBUV total ozone with Dobson [Fleig et a... more Using techniques very similar to those used in comparing SBUV total ozone with Dobson [Fleig et al. 1986A], seven years of total ozone data derived from the TOMS instrument on Nimbus‐7 are compared with results from 41 Dobson stations. In this study however, a ...
Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus ... more Three ozone tape products from the Solar Backscatter Ultraviolet (SBUV) experiment aboard Nimbus 7 were archived at the National Space Science Data Center. The experiment measures the fraction of incoming radiation backscattered by the Earth's atmosphere at 12 wavelengths. In-flight measurements were used to monitor changes in the instrument sensitivity. Total column ozone is derived by comparing the measurements with calculations of what would be measured for different total ozone amounts. The altitude distribution is retrieved using an optimum statistical technique for the inversion. The estimated initial error in the absolute scale for total ozone is 2 percent, with a 3 percent drift over 8 years. The profile error depends on latitude and height, smallest at 3 to 10 mbar; the drift increases with increasing altitude. Three tape products are described. The High Density SBUV (HDSBUV) tape contains the final derived products - the total ozone and the vertical ozone profile - as ...
Journal of Geophysical Research, 2003
IEEE Transactions on Geoscience and Remote Sensing, 2013
Journal of Geophysical Research, 2003
IEEE Transactions on Geoscience and Remote Sensing, 2006
IEEE Transactions on Geoscience and Remote Sensing, 2006
IEEE Transactions on Geoscience and Remote Sensing, 2006
Advances in Space Research, 1982
... REFERENCES 1. GHB Dobson and DN Harrison, Proc. Roy. Soc., Ser. A 110, 660 (1926) 2. FE Fowle... more ... REFERENCES 1. GHB Dobson and DN Harrison, Proc. Roy. Soc., Ser. A 110, 660 (1926) 2. FE Fowle, Smithsonian Miscellaneous Collections 81, 1 (1929) 3. GM Keating, L. Frank, JD Craven, D. Young, J. Nicholson, P. Bhartia, D. Gordon, EOS, Trans. ...
IEEE Transactions on Geoscience and Remote Sensing, 2006
<p>The NASA TOMS V9 (TOMS-V9) total ozone retrieval algorithm is tested<br>for sensit... more <p>The NASA TOMS V9 (TOMS-V9) total ozone retrieval algorithm is tested<br>for sensitvity to boundary-layer ozone and suitability to make daily<br>maps of tropospheric ozone residual (TOR).  Daily maps of TOR are<br>derived by differencing co-located MERRA-2 assimilated MLS<br>stratospheric column ozone (SCO) from total column ozone from the Aura<br>Ozone Monitoring Instrument (OMI).  The TOMS-V9 algorithm uses a few<br>discrete channels with an order of magnitude range in ozone<br>senstivity. We compare the TOR results from TOMS-V9 with results from<br>several hyper-spectral total ozone retrievals: GODFIT v4 (BIRA-IASB),<br>OMI-DOAS (KNMI), and total ozone from the SAO PROFOZ algorithm. We<br>compare all satellite-retrieved TOR with TOR derived from ozonesondes,<br>lidar, and the Goddard Modeling Initiative (GMI) model simulation.</p><p> </p><p> </p>
An assessment of OMI retrievals of aerosol properties is presented. We compare OMI retrieved valu... more An assessment of OMI retrievals of aerosol properties is presented. We compare OMI retrieved values of extinction and absorption optical depth, and aerosol single scattering albedo to AERONET ground-based measurements. An evaluation of the accuracy of the retrievals for a limited number of observations under cloud-free conditions shows a positive offset of about 0.03 in retrieved optical depth. This small offset is an indication of accurate sensor calibration to the 1% level. The retrieved SSA values agree well with RMS differences of 0.02-0.03 compared with the AERONET observations. This result shows that the UV technique is a very valuable tool for measuring aerosol absorption from space.
We discuss collection 2 SO2 data from the Dutch-Finnish Ozone Monitoring Instrument (OMI) on boar... more We discuss collection 2 SO2 data from the Dutch-Finnish Ozone Monitoring Instrument (OMI) on board NASA EOS/Aura spacecraft and show examples of detected volcanic and anthropogenic SO2 emissions. Quantification of anthropogenic SO2 emissions requires collection 3 reprocessing available in the fall 2007.