
James B. AbshireNational Aeronautics and Space Administration · Solar System Exploration Division
James B. Abshire
Ph.D.
About
315
Publications
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Introduction
Additional affiliations
Position
- NASA Goddard Space Flight Center
Education
August 1974 - June 1982
Publications
Publications (315)
We measured the column-averaged atmospheric CO2 mixing ratio (XCO2) to a variety of cloud tops with an airborne pulsed multi-wavelength integrated path differential absorption (IPDA) lidar during NASA's 2017 ASCENDS/ABoVE airborne campaign. Measurements of height-resolved atmospheric backscatter profiles allow this lidar to retrieve XCO2 to cloud t...
We measured the column-averaged atmospheric CO2 mixing ratio (XCO2) to a variety of cloud tops with an airborne pulsed multi-wavelength integrated path differential absorption (IPDA) lidar during NASA’s 2017 ASCENDS/ABoVE field campaign. Measurements of height- resolved atmospheric backscatter profiles allow this lidar technique to estimate XCO2 to...
A series of attenuated atmospheric backscatter profiles were measured at 1572 nm by the CO2 Sounder lidar during the eight flights of the 2017 ASCENDS/ABoVE (Active Sensing of CO2 Emission over Nights, Days, and Seasons, Arctic Boreal Vulnerability Experiment) airborne campaign. In addition to measuring the column average CO2 mixing ratio from the...
A series of attenuated atmospheric backscatter profiles were measured at 1572 nm by the CO2 Sounder lidar during the eight flights of the 2017 ASCENDS/ABoVE (Active Sensing of CO2 Emission over Nights, Days, & Seasons mission, Arctic Boreal Vulnerability Experiment) airborne campaign. In addition to measuring the column average CO2 mixing ratio fro...
Plain Language Summary
Wildfires are a major source of greenhouse gases. However, there are large uncertainties in the estimated CO2 emissions from wildfires in global emissions inventories. The estimates of column‐averaged CO2 (XCO2) from satellite measurements using passive remote sensing techniques are significantly degraded or screened out by t...
Space missions to study small solar system bodies, such as asteroids and comet cores, are enhanced by lidar that can provide global mapping and serve as navigation sensors for landing and surface sampling. A small swath-mapping lidar using a fiber laser modulated by pseudo-noise (PN) codes is well-suited to small space missions and can provide cont...
The retrieval algorithm for CO2 column mixing ratio from measurements of a pulsed multi-wavelength integrated path differential absorption (IPDA) lidar is described. The lidar samples the shape of the 1572.33 nm CO2 absorption line at multiple wavelengths. The algorithm uses a least-squares fit between the CO2 line shape computed from a layered atm...
We report the development of a new type of space lidar specifically designed for missions to small planetary bodies for both topographic mapping and support of sample collection or landing. The instrument is designed to have a wide dynamic range with several operation modes for different mission phases. The laser transmitter consists of a fiber las...
The Science Case for a Titan Flagship-class Orbiter with Probes
White paper #325 submitted to the Planetary Science and Astrobiology Decadal Survey 2023-2032. Topics: giant planets systems; ocean worlds; other: Mission Studies
by Conor Nixon, James Abshire, Andrew Ashton, Jason W. Barnes, Nathalie Carrasco, Mathieu Choukroun, Athena Coustenis, Lo...
The retrieval algorithm for the column mixing ratio of CO2 from the measurements of a pulsed multi-wavelength integrated path differential absorption (IPDA) lidar is described. The lidar samples the shape of the 1572.33 nm CO2 absorption line at 15 or 30 wavelengths. The algorithm uses a least-squares fit between the CO2 line shape computed from a...
Space radiation damage and proton induced transient effects were evaluated on 4.4 μm cutoff HgCdTe avalanche photodiode (APD) arrays developed by Leonardo DRS. Device performances as a function of total dose up to 100 krad (Si) were measured with ~60 MeV protons on 3 types of APD samples: 4x4 pixel APD fanout arrays with and without connection to a...
We outline a flagship-class mission concept focused on studying Titan as a global system, with particular emphasis on the polar regions. Investigating Titan from the unique standpoint of a polar orbit would enable comprehensive global maps to uncover the physics and chemistry of the atmosphere, and the topography and geophysical environment of the...
Wind is the process that connects Mars' climate system. Measurements of Mars atmospheric winds from orbit would dramatically advance our understanding of Mars and help prepare for human exploration of the Red Planet. Multiple instrument candidates are in development and will be ready for flight in the next decade. We urge the Decadal Survey to make...
The present knowledge of the Mars atmosphere is greatly limited by a lack of global measurements of winds and aerosols. Hence, measurements of height-resolved wind and aerosol profiles are a priority for new Mars orbiting missions. We have designed a direct-detection lidar (MARLI) to provide global measurements of dust, winds and water ice profiles...
Observations taken over the last few decades indicate that dramatic changes are occurring in the Arctic‐Boreal Zone (ABZ), which are having significant impacts on ABZ inhabitants, infrastructure, flora and fauna, and economies. While suitable for detecting overall change, the current capability is inadequate for systematic monitoring and for improv...
NASA-Goddard is developing a high-fidelity space-based remote sensor for atmospheric CO2. We report on a the instrument architecture and performance and the technology developments for a low earth orbiting instrument.
Improved remote sensing observations of atmospheric carbon dioxide (CO2) are critically needed to quantify, monitor, and understand the Earth’s carbon cycle and its evolution in a changing climate. The processes governing ocean and terrestrial carbon uptake remain poorly understood, especially in dynamic regions with large carbon stocks and strong...
We review the singular value decomposition (SVD) framework and use it for quantifying and discerning vertical information in greenhouse gas retrievals from column integrated absorption measurements. While the commonly used traditional Bayesian optimal estimation (OE) assumes a prior distribution in order to regularize the inversion problem, the SVD...
Here we report on measurements made with an improved CO2 Sounder lidar during the ASCENDS 2014 and 2016 airborne campaigns. The changes made to the 2011 version of the lidar included incorporating a rapidly wavelength-tunable, step-locked seed laser in the transmitter, using a much more sensitive HgCdTe APD detector and using an analog digitizer wi...
We review the singular value decomposition (SVD) framework and use it for quantifying and discerning vertical information in greenhouse gas retrievals from column integrated absorption measurements. While the commonly used traditional Bayesian optimal estimation (OE) assumes a prior distribution in order to regularize the inversion problem, the SVD...
We have measured the column-averaged atmospheric CO2 mixing ratio to a variety of cloud tops by using an airborne pulsed multi-wavelength integrated-path differential absorption (IPDA) lidar. Airborne measurements were made at altitudes up to 13 km during the 2011, 2013 and 2014 NASA Active Sensing of CO2 Emissions over Nights, Days, and Seasons (A...
NASA Goddard Space Flight Center has been developing an integrated path differential absorption (IPDA) lidar instrument concept to measure the column concentrations of atmospheric carbon dioxide (CO2) from space. We will discuss the development effort of a space-qualified, single frequency, fiber-based master oscillator power amplifier with >450 µJ...
We report on an airborne demonstration of atmospheric oxygen (O2) optical depth measurements with an Integrated Path Differential Absorption (IPDA) lidar using a fiber-based laser transmitter and photon counting detectors. Accurate atmospheric temperature and pressure measurements are needed for NASA’s Active Sensing of CO2 Emissions over Nights, D...
Here we report on measurements made with an improved CO2 Sounder lidar during the ASCENDS 2014 and 2016 airborne campaigns. The improvements made to the 2011 version of the lidar instrument included incorporating a rapidly wavelength tunable, step-locked seed laser in the transmitter, using a much more sensitive HgCdTe APD detector, and using an an...
The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently...
NASA's Ice, Cloud, and land Elevation Satellite (ICESat), which operated between 2003 and 2009, made the first satellite-based global lidar measurement of earth's ice sheet elevations, sea-ice thickness, and vegetation canopy structure. The primary instrument on ICESat was the Geoscience Laser Altimeter System (GLAS), which measured the distance fr...
We have measured the column-averaged atmospheric CO2 mixing ratio to a variety of cloud tops by using an airborne pulsed multiple wavelengths integrated-path, differential absorption (IPDA) lidar. Airborne measurements were made at altitudes up to 13 km during the 2011, 2013 and 2014 ASCENDS science campaigns flown in the west and mid-west United S...
We report results from characterizing the HgCdTe avalanche photodiode (APD) arrays developed for lidar at infrared wavelengths by using the high density vertically integrated photodiodes (HDVIP®) technique. The results show >90% quantum efficiencies between 0.8 μm and the cut-off wavelength, >600 APD gain, near unity excess noise factor, 6-10 MHz e...
We have advanced the science of space-based laser measurements using the spectral purity and frequency tuning of a fiber-amplified lasers performing active remote sensing of atmospheric CO2 column abundance and dry mixing ratio.
The advent of several key enabling electro-optics technologies afford advanced, non-topographic remote sensing instruments for space. We will present progress on several new, space-based laser instruments that are being developed at NASA GSFC. Article not available.
An overview of recent improvements in our understanding of, and the maturity of, linear-mode photon counting with the HgCdTe electron-initiated avalanche photodiode is presented. In 2010 DRS fabricated an experimental 2 × 8 array with (64 μm)2 pixels which enabled, for the first time, linear-mode photon counting by use of the MWIR cutoff HgCdTe ele...
NASA’s Goddard Space Flight Center (GSFC) is working on maturing the technology readiness of a laser transmitter designed for use in atmospheric CO2 remote-sensing. GSFC has been developing an airplane-based CO2 lidar instrument over several years to demonstrate the efficacy of the instrumentation and measurement technique and to link the science m...
For several years now, NASA has supported observing system simulation studies to evaluate measurement capabilities and requirements for the ASCENDS mission in the context of advancing our knowledge of carbon flux distributions and their dependence on underlying physical processes. ASCENDS (Active Sensing of Carbon Emissions, Nights, Days, and Seaso...
Results of characterization data on linear mode photon counting (LMPC) HgCdTe electron-initiated avalanche photodiode (e-APD)focal plane arrays (FPA) are presented that reveal an improved understanding and the growing maturity of the technology. The first successful 2x8 LMPC FPA was fabricated in 2010 [1]. Since then a process validation lot of 2x8...
Accurate global measurements of tropospheric CO2 mixing ratios are needed to better understand the global carbon cycle and the CO2 exchange between land, oceans and atmosphere. NASA Goddard Space Flight Center (GSFC) is developing a pulsed lidar approach for an integrated path differential absorption (IPDA) lidar as a candidate for the NASA?€™s pla...
We have measured the CO2 volume mixing ratio (VMR) within the planetary boundary layer (PBL) using cloud slicing with an airborne pulsed integrated path differential absorption (IPDA) lidar from altitudes of up to 13 km. During a flight over Iowa in 2011, simultaneous measurement of the optical range and CO2 absorption to clouds and the ground were...
An orbiting laser remote sensing instrument (lidar) capable of measuring trace gases on global scales with unprecedented accuracy and high spatial resolution can provide valuable measurements for planetary and earth science missions.
In this paper we will review our progress on maturing the technology and improving the technical readiness of a fiber-based laser transmitter at 1.57 μm for use in atmospheric carbon dioxide (CO2) satellite remote-sensing.
This presentation will discuss the application of lidar approaches to remotely measure the column abundance of CO2 and other atmospheric greenhouse gases from space. It will discuss recent airborne campaigns, ongoing work and plans for future space missions.
The objectives of NASA's ASCENDS mission are to improve the knowledge of global CO sources and sinks by precisely measuring the tropospheric column abundance of atmospheric CO and O. The mission will use a continuously operating nadir-pointed integrated path differential absorption (IPDA) lidar in a polar orbit. The lidar offers a number of importa...
An HgCdTe electron avalanche photodiode (e-APD) detector has been developed for lidar receivers, one application of which is integrated path differential absorption lidar measurements of such atmospheric trace gases as CO2 and CH4. The HgCdTe APD has a wide, visible to mid-wave-infrared, spectral response, high dynamic range, substantially improved...
A multi-element HgCdTe electron initiated avalanche photodiode (e-APD) array has been developed for space lidar. The detector array was fabricated with 4.3μm cutoff HgCdTe with a spectral response from 0.4 to 4.3 μm. We have demonstrated a 4x4 e-APD array with 80 μm square elements followed by a custom cryogenic CMOS read-out integrated circuit (RO...
The Total Carbon Column Observing Network (TCCON) is a global network of ground-based Fourier Transform Spectrometers recording direct solar spectra in the near-infrared spectral region. With stringent requirements on the instrumentation, data processing and calibration, accurate and precise column-averaged abundances of CO2, CH4, N2O, HF, CO, H2O,...
An infrared reflectance lidar obtains multispectral data near 3 µm to map ice in the lunar polar regions. Visible fluorescence seeks organics.
Tellurite waveguides are promising candidates for high gain with broad-bandwidth, especially with Er-doping, which covers the telecommunications band and important spectral absorption features of atmospheric CO2. This study aimed at developing new Er,Yb-doped tellurite waveguide power amplifier modules suited to LIDAR measurements from space that w...
MARBLL is an optical remote sensing instrument
using a mature state-of-the-art Doppler
wind lidar technology specifically designed to
operate at the surface of Mars. The instrument
includes an emitting device (laser) and a spectral
analyzer (Mach-Zehnder interferometer). Wind
profiling is inferred from the 1064 nm beam emitted
by the laser and subs...
Tellurite waveguides are promising candidates for high gain with broad-bandwidth, especially with Er-doping, which covers the telecommunications band and important spectral absorption features of atmospheric CO2. This study aimed at developing new Er,Yb-doped tellurite waveguide power amplifier modules suited to LIDAR measurements from space that w...
We have previously demonstrated a pulsed direct detection IPDA lidar to measure range and the column concentration of atmospheric CO2. The lidar measures the atmospheric backscatter profiles and samples the shape of the 1,572.33 nm CO2 absorption line. We participated in the ASCENDS science flights on the NASA DC-8 aircraft during August 2011 and r...
NASA Goddard is developing an integrated-path, differential absorption (IPDA) lidar approach to measure
atmospheric CO2 concentrations from space as a candidate for NASA’s ASCENDS (Active Sensing of CO2
Emissions over Nights, Days, and Seasons) mission. The approach uses pulsed lasers to measure both CO2
and O2 absorption simultaneously in the vert...
The measurement of atmospheric CO2 from space using active (lidar) sensing techniques has several
potentially significant advantages in comparison to current and planned passive CO2 instruments.
Application of this new technology aims to advance CO2 measurement capability and carbon cycle science
into the next decade. The NASA Active Sensing of Car...
We have developed a pulsed, wavelength-resolved IPDA lidar technique for measuring the tropospheric CO2
concentrations as a candidate for NASA’s ASCENDS mission. The CO2 lidar flies on NASA’s DC-8 aircraft
and measures the atmospheric backscatter profiles and shape of the 1572.33 nm absorption line using 250
mW average laser power, 30 wavelength sa...
We report on an airborne demonstration of atmospheric oxygen optical depth measurements with an IPDA lidar using a fiber-based laser system and a photon counting detector. Accurate knowledge of atmospheric temperature and pressure is required for NASA’s Active Sensing of CO 2 Emissions over Nights, Days, and Seasons (ASCENDS) space mission, and cli...