A5018492174- Atmospheric and Environmental Gas Dynamics
- Spectroscopy and Laser Applications
- Atmospheric Ozone and Climate
- Calibration and Measurement Techniques
- Laser Design and Applications
- Atmospheric chemistry and aerosols
- Space Exploration and Technology
- Atmospheric aerosols and clouds
- Climate change and permafrost
- Planetary Science and Exploration
- Combustion and flame dynamics
- Methane Hydrates and Related Phenomena
- Spacecraft and Cryogenic Technologies
- Astro and Planetary Science
- Advanced Sensor Technologies Research
- Satellite Image Processing and Photogrammetry
- Hydrocarbon exploration and reservoir analysis
- Photonic and Optical Devices
- Spacecraft Design and Technology
- Astronomical Observations and Instrumentation
- Advanced Combustion Engine Technologies
- Cryospheric studies and observations
- Air Quality Monitoring and Forecasting
- CCD and CMOS Imaging Sensors
- IoT-based Smart Home Systems
Goddard Space Flight Center
2012-2022
NASA Earth Science
2022
American University
2015
National Aeronautics and Space Administration
2008-2009
National Academy of Sciences
2003-2004
National Academies of Sciences, Engineering, and Medicine
2003-2004
George Washington University
2001-2002
We have developed a low-cost, miniaturized laser heterodyne radiometer for highly sensitive measurements of carbon dioxide (CO2) in the atmospheric column. In this passive design, sunlight that has undergone absorption by CO2 atmosphere is collected and mixed with continuous wave light step-scanned across feature centered at 1,573.6 nm. The resulting radio frequency beat signal as function wavelength, from which total column mole fraction can be de-convolved. are expanding technique to...
We present column CO2 measurements taken by the passive miniaturized laser heterodyne radiometer (Mini-LHR) at 1611.51 nm Mauna Loa Observatory in Hawaii. The Mini-LHR was operated autonomously, during month of May 2013 this site, working tandem with an AERONET sun photometer that measures aerosol optical depth 15-min intervals daylight hours. Laser radiometry has been used since 1970s to measure atmospheric gases such as ozone, water vapor, methane, ammonia, chlorine monoxide, and nitrous...
We present a design for 4 U (20 cm × 20 10 cm) occultation-viewing laser heterodyne radiometer (LHR) that measures methane (CH4), carbon dioxide (CO2) and water vapor (H2O) in the limb is designed deployment on 6 CubeSat. The LHR collects sunlight has undergone absorption by trace gas mixes it with distributive feedback (DFB) centered at 1640 nm scans across CO2, CH4, H2O features. Upper troposphere/lower stratosphere measurements of these gases provide key inputs to stratospheric...
Presented here is a sensitivity analysis for the miniaturized laser heterodyne radiometer. This passive, ground-based instrument measures carbon dioxide (CO2) in atmospheric column and has been under development at NASA/GSFC since 2009. The goal of this to produce low-cost, easily-deployable that can extend current ground measurement networks order (1) validate satellite observations, (2) provide coverage regions limited (3) target interest such as thawing permafrost, (4) support continuity...
NASA’s return to the Moon coincides with explosive growth in exoplanet discovery. Missions are being formulated search for habitable planets orbiting other stars, making this ideal time deploy an instrument suite lunar surface help us recognize a when we see it. We present EarthShine, technically mature, three-instrument observe whole Earth from as proxy. EarthShine data will validate and improve models critical designing missions image characterize exoplanets, thus informing observing...
Progress on a passive Fabry–Perot-based instrument for detecting column CO2 through absorption measurements at 1.58 µm is described. In this design, solar flux reaches the platform and directed two channels. first channel, transmittance fringes from Fabry–Perot interferometer are aligned with lines so that due to primarily detected. The second channel encompasses same frequency region as first, but comparatively more sensitive changes in than CO2. ratio of these channels total column, not...
We report on progress of our CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> laser sounder laboratory breadboard system the goal which is to measure integrated column abundance better than 1 ppm from low Earth orbit globally, measuring at all latitudes and seasons through day night. The challenge for an orbiting instrument achieve high precision not sensitivity. have made simple yet significant improvements active, optical-sensing...
Mounting concern regarding global warming and the increasing carbon dioxide (CO<sub>2</sub>) concentration has stimulated interest in feasibility of measuring CO<sub>2</sub> mixing ratios from space. Precise satellite observations with adequate spatial temporal resolution would substantially increase our knowledge atmospheric CO<sub>2</sub>distribution allow improved modeling cycle. Current estimates indicate that a measurement precision better than 1 part per million (1 ppm) will be needed...
Abstract. We present observing system simulation experiments (OSSEs) to evaluate the impact of a proposed network ground-based miniaturized laser heterodyne radiometer (mini-LHR) instruments that measure atmospheric column-averaged carbon dioxide (XCO2) with 1 ppm precision. A particular strength this passive measurement approach is its insensitivity clouds and aerosols due direct sun pointing narrow field view (0.2∘). Developed at NASA Goddard Space Flight Center (GSFC), these portable,...
We report progress in assessing the feasibility of a new satellite-based laser-sounding instrument to measure CO2concentrations lower troposphere from space.
A passive instrument based on a Fabry-Perot interferometer was designed and used for oxygen atmospheric column absorption measurements. The operates in the A-band spectral region from 759 to 771 nm. Surface solar irradiation reflected off Earth is detected using two channels at wavelengths—one pressure sensing other temperature sensing. Each channel of O2 measurement system consists subchannels—Fabry-Perot reference. Solid etalons were confine response bands. have free ranges 0.575, 0.802,...
A new type of remote-sensing radiometer based upon the Fabry-Perot (FP) interferometric technique has been developed at NASA's Goddard Space Flight Center and tested from both ground aircraft platforms. The sensor uses direct or reflected sunlight channels for measuring column concentration carbon dioxide 1570 nm, oxygen lines sensitive to pressure temperature 762 768 water vapor (940 nm). solid FP etalon is used as a tunable narrow bandpass filter restrict measurement gas interest's...
To address the problem of sources and sinks atmospheric CO 2 , measurements are needed on a global scale. Satellite instruments show promise, but typically measure total column. Since at surface represent small perturbation to column, precision better than 1% is required. No species has ever been measured from space this level. Over last three years, we have developed instrument based upon Fabry-Perot interferometer that highly sensitive . We tested in ground configuration aircraft platforms...
We are presenting new experimental data on atmospheric carbon dioxide and oxygen column absorption collected with a passive instrument developed at Goddard Space Flight Center called FPICC (Fabry-Perot Interferometer for Column CO<sub>2</sub>). The were recorded board of NASA's DC-8 flight laboratory during the PAVE experiment (Polar Aura Validation Experiment), January 2005. precise alignment transmission peaks Fabry-Perot etalon to CO<sub>2</sub> lines is achieved through altering...
A pulsed quartz microprobe has been developed for time-resolved, extractive sampling in a time-varying (flickering) flame. The probe used tunable diode laser absorption spectroscopic detection of carbon dioxide and nitric oxide 10 Hz, acoustically forced, air-diluted natural gas, non-premixed design the satisfies requirements rapid temporal response, low dead volume using chemically inert materials. For selected heights radial locations, mole fractions were found to track one another through...
The FPICC (Fabry-Perot Interferometer for Column CO<sub>2</sub>) is a new instrument developed under the Instrument Incubator Program that uses novel technique measuring absorption of CO<sub>2</sub> sunlight reflected from Earth. optical setup consists three channels. first channel built to measure carbon dioxide by using solid Fabry-Perot etalon restrict measurement light in bands. second and third channels focus on O<sub>2</sub> A band (759-771 nm) composed about 300 lines, which vary...
We present preliminary results in the development of a miniaturized gas correlation radiometer that implements hollow-core optical fiber (hollow-waveguide) cell. The substantial reduction mass and volume cell makes this technology appropriate for an orbital mission—capable pinpointing sources trace gases Martian atmosphere. Here, we demonstrate formaldehyde (H2CO) sensor report detection limit equivalent to ∼30 ppb relative simplicity technique allows it be expanded measure range atmospheric...
The experimental data on CO<sub>2</sub> detection in atmosphere using Fabry-Perot technique are presented. optical setup consists of two channels. Channel one measure the total reflected light, whereas channel uses a solid substrate etalon to restrict measurement light absorption bands. free spectral range is calculated be equal almost regular spacing between bands located near 1.58 μm, where significant. ratio intensities detected by channels then sensitive change. We exploring...
The experimental data on CO<sub>2</sub> and O<sub>2</sub> detection in atmosphere using Fabry-Perot technique are presented. atmosphere's irradiance measurements an important tool for the remote sensing study. We show results from lab, ground flight testing of a new instrument called FPICC (Fabry-Perot Interferometer Column CO<sub>2</sub>) which is intended very precise atmospheric carbon dioxide oxygen. optical setup consists three channels. first channel built to measure dioxide. This...
The experimental data on O<sub>2</sub> absorption using reflected sunlight and a passive Fabry-Perot technique are presented. atmosphere's irradiance measurements an important tool for the remote sensing study. In this work we focus A band (759-771 nm) composed of about 300 lines, which vary in strength width according to pressure temperature. We performed solid etalons with different FSR two pre-filters. first pre-filter selects spectral range around 763 nm is between P R branches, where...