Results from the NASA GSFC and LaRC Ozone Lidar Intercomparison: New Mobile Tools for Atmospheric Research

AbstractDuring a 2-week period in May 2014, the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center Tropospheric Ozone Differential Absorption Lidar (GSFC TROPOZ DIAL) was situated near the NASA Langley Research Center (LaRC) Mobile Ozone Lidar (LMOL) and made simultaneous measurements for a continuous 15-h observation period in which six separate ozonesondes were launched to provide reference ozone profiles. Although each of these campaign-ready lidars has very different transmitter and receiver components, they produced very similar ozone profiles, which were mostly within 10% of each other and the ozonesondes. The observed column averages as compared to the ozonesondes also agree well and are within 8% of each other. A robust uncertainty analysis was performed, and the results indicate that there is no statistically significant systematic bias between the TROPOZ and LMOL instruments. With the extended measurements and ozonesonde launches, this intercomparison has yielded an in-depth evaluation of the precision and accuracy of the two new lidars. This intercomparison is also the first (to the best of the authors’ knowledge) reported measurement intercomparison of two ground-based tropospheric ozone lidar systems within the United States.

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A mobile differential absorption lidar to measure sub-hourly fluctuation of tropospheric ozone profiles in the Baltimore–Washington, D.C. region

Atmospheric Measurement Techniques ◽

10.5194/amt-7-3529-2014 ◽

2014 ◽

Vol 7 (10) ◽

pp. 3529-3548 ◽

Cited By ~ 33

Author(s):

J. T. Sullivan ◽

T. J. McGee ◽

G. K. Sumnicht ◽

L. W. Twigg ◽

R. M. Hoff

Keyword(s):

Tropospheric Ozone ◽

Stratospheric Ozone ◽

Surface Ozone ◽

Buffer Gas ◽

Differential Absorption ◽

Differential Absorption Lidar ◽

Nasa Goddard Space ◽

Multiple Receivers ◽

Ozone Profile ◽

The Us

Abstract. Tropospheric ozone profiles have been retrieved from the new ground-based National Aeronautics and Space Administration (NASA) Goddard Space Flight Center TROPospheric OZone DIfferential Absorption Lidar (GSFC TROPOZ DIAL) in Greenbelt, MD (38.99° N, 76.84° W, 57 m a.s.l.), from 400 m to 12 km a.g.l. Current atmospheric satellite instruments cannot peer through the optically thick stratospheric ozone layer to remotely sense boundary layer tropospheric ozone. In order to monitor this lower ozone more effectively, the Tropospheric Ozone Lidar Network (TOLNet) has been developed, which currently consists of five stations across the US. The GSFC TROPOZ DIAL is based on the DIAL technique, which currently detects two wavelengths, 289 and 299 nm, with multiple receivers. The transmitted wavelengths are generated by focusing the output of a quadrupled Nd:YAG laser beam (266 nm) into a pair of Raman cells, filled with high-pressure hydrogen and deuterium, using helium as buffer gas. With the knowledge of the ozone absorption coefficient at these two wavelengths, the range-resolved number density can be derived. An interesting atmospheric case study involving the stratospheric–tropospheric exchange (STE) of ozone is shown, to emphasize the regional importance of this instrument as well as to assess the validation and calibration of data. There was a low amount of aerosol aloft, and an iterative aerosol correction has been performed on the retrieved data, which resulted in less than a 3 ppb correction to the final ozone concentration. The retrieval yields an uncertainty of 16–19% from 0 to 1.5 km, 10–18% from 1.5 to 3 km, and 11–25% from 3 to 12 km according to the relevant aerosol concentration aloft. There are currently surface ozone measurements hourly and ozonesonde launches occasionally, but this system will be the first to make routine tropospheric ozone profile measurements in the Baltimore–Washington, D.C. area.

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Development of a human factors methodology for NASA-Goddard space flight center

PsycEXTRA Dataset ◽

10.1037/e574092012-009 ◽

1983 ◽

Author(s):

Paula M. Van Balen ◽

Christine M. Mitchell

Keyword(s):

Human Factors ◽

Space Flight ◽

Nasa Goddard Space ◽

Goddard Space ◽

Goddard Space Flight Center

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Counter culture: Causes, extent and solutions of systematic bias in the analysis of behavioural counts

10.32942/osf.io/jq9n6 ◽

2019 ◽

Cited By ~ 2

Author(s):

Joel L Pick ◽

Nyil Khwaja ◽

Michael A. Spence ◽

Malika Ihle ◽

Shinichi Nakagawa

Keyword(s):

Recent Literature ◽

Null Model ◽

Mechanistic Explanation ◽

Effect Sizes ◽

Systematic Bias ◽

Intra Class Correlation ◽

Counter Culture ◽

Provisioning Rate ◽

Parental Provisioning ◽

Observation Period

We often quantify a behaviour by counting the number of times it occurs within a specific, short observation period. Measuring behaviour in such a way is typically unavoidable but induces error. This error acts to systematically reduce effect sizes, including metrics of particular interest to behavioural and evolutionary ecologists such as R2, repeatability (intra-class correlation, ICC) and heritability. Through introducing a null model, the Poisson process, for modelling the frequency of behaviour, we give a mechanistic explanation of how this problem arises and demonstrate how it makes comparisons between studies and species problematic, because the magnitude of the error depends on how frequently the behaviour has been observed (e.g. as a function of the observation period) as well as how biologically variable the behaviour is. Importantly, the degree of error is predictable and so can be corrected for. Using the example of parental provisioning rate in birds, we assess the applicability of our null model for modelling the frequency of behaviour. We then review recent literature and demonstrate that the error is rarely accounted for in current analyses. We highlight the problems that arise from this and provide solutions. We further discuss the biological implications of deviations from our null model, and highlight the new avenues of research that they may provide. Adopting our recommendations into analyses of behavioural counts will improve the accuracy of estimated effect sizes and allow meaningful comparisons to be made between studies.

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Preliminary Results of the NASA/Goddard Space Flight Center Short Pulse Radar Ocean Waves Sensing Program

10.1109/oceans.1979.1151325 ◽

1979 ◽

Author(s):

F. Jackson ◽

W. Walton ◽

D. LeVine ◽

J. Eckerman ◽

R. Kutz

Keyword(s):

Space Flight ◽

Short Pulse ◽

Ocean Waves ◽

Preliminary Results ◽

Nasa Goddard Space ◽

Pulse Radar ◽

Goddard Space ◽

Goddard Space Flight Center

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Ground-based temperature and humidity profiling: combining active and passive remote sensors

Atmospheric Measurement Techniques ◽

10.5194/amt-14-3033-2021 ◽

2021 ◽

Vol 14 (4) ◽

pp. 3033-3048

Author(s):

David D. Turner ◽

Ulrich Löhnert

Keyword(s):

Water Vapor ◽

Information Content ◽

Great Plains ◽

Optimal Estimation ◽

Differential Absorption ◽

Southern Great Plains ◽

Atmospheric Research ◽

Remote Sensors ◽

Central Portugal ◽

Atmospheric Radiation Measurement

Abstract. Thermodynamic profiles in the planetary boundary layer (PBL) are important observations for a range of atmospheric research and operational needs. These profiles can be retrieved from passively sensed spectral infrared (IR) or microwave (MW) radiance observations or can be more directly measured by active remote sensors such as water vapor differential absorption lidars (DIALs). This paper explores the synergy of combining ground-based IR, MW, and DIAL observations using an optimal-estimation retrieval framework, quantifying the reduction in the uncertainty in the retrieved profiles and the increase in information content as additional observations are added to IR-only and MW-only retrievals. This study uses ground-based observations collected during the Perdigão field campaign in central Portugal in 2017 and during the DIAL demonstration campaign at the Atmospheric Radiation Measurement Southern Great Plains site in 2017. The results show that the information content in both temperature and water vapor is higher for the IR instrument relative to the MW instrument (thereby resulting in smaller uncertainties) and that the combined IR + MW retrieval is very similar to the IR-only retrieval below 1.5 km. However, including the partial profile of water vapor observed by the DIAL increases the information content in the combined IR + DIAL and MW + DIAL water vapor retrievals substantially, with the exact impact vertically depending on the characteristics of the DIAL instrument itself. Furthermore, there is a slight increase in the information content in the retrieved temperature profile using the IR + DIAL relative to the IR-only; this was not observed in the MW + DIAL retrieval.

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Flight Demonstration of a 2-Micron, Double Plused CO2 IPDA Lidar Instrument

EPJ Web of Conferences ◽

10.1051/epjconf/202023703013 ◽

2020 ◽

Vol 237 ◽

pp. 03013

Author(s):

Jirong Yu ◽

Mulugeta Petros ◽

Upendra Singh ◽

Tamer Refaat ◽

Karl Reithmaier ◽

...

Keyword(s):

Column Density ◽

High Energy ◽

Density Difference ◽

Lidar Measurement ◽

Differential Absorption ◽

Air Samples ◽

Lidar Measurements ◽

Langley Research Center ◽

Good Agreement

NASA Langley Research Center (LaRC) developed a double pulsed, high energy 2-micron Integrated Path Differential Absorption (IPDA) lidar instrument to measure atmospheric CO2 column density. The 2-μm double pulsed IPDA lidar was flown ten times in March and April of 2014. It was determined that the IPDA lidar measurement is in good agreement with an in-situ CO2 measurement by a collocated NOAA flight. The average column CO2 density difference between the IPDA lidar measurements and the NOAA air samples is 1.48ppm in the flight altitudes of 3 to 6.1 km.

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Observing System Simulation Experiments to Assess the Potential Impact of New Observing Systems on Hurricane Forecasting

Marine Technology Society Journal ◽

10.4031/mtsj.49.6.3 ◽

2015 ◽

Vol 49 (6) ◽

pp. 140-148 ◽

Cited By ~ 19

Author(s):

Robert Atlas ◽

Lisa Bucci ◽

Bachir Annane ◽

Ross Hoffman ◽

Shirley Murillo

Keyword(s):

System Simulation ◽

Weather Prediction ◽

Simulation Experiments ◽

Nasa Goddard Space ◽

Trade Offs ◽

Goddard Space Flight Center ◽

Hurricane Track ◽

Potential Impact ◽

Hurricane Forecasting ◽

Observing Systems

AbstractObserving System Simulation Experiments (OSSEs) are an important tool for evaluating the potential impact of new or proposed observing systems, as well as for evaluating trade-offs in observing system design, and in developing and assessing improved methodology for assimilating new observations. Extensive OSSEs have been conducted at the National Aeronautical and Space Administration (NASA) Goddard Space Flight Center (GSFC) and the National Oceanic and Atmospheric Administration (NOAA) Atlantic Oceanographic and Meteorological Laboratory (AOML) over the last three decades. These OSSEs determined correctly the quantitative potential for several proposed satellite observing systems to improve weather analysis and prediction prior to their launch; evaluated trade-offs in orbits, coverage, and accuracy for space-based wind lidars; and were used in the development of the methodology that led to the first beneficial impacts of satellite surface winds on numerical weather prediction. This paper summarizes early applications of global OSSEs to hurricane track forecasting and new experiments using both global and regional models. These latter experiments are aimed at assessing potential impact on hurricane track and intensity prediction over the oceans and at landfall.

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