ACT-America Campaign Catalog

The ACT-America Campaign Catalog provides information about the airborne campaigns of the Atmospheric Carbon and Transport (ACT-America) project. The Catalog compiles flight details for the five campaigns conducted during Summer 2016, Winter 2017, Fall 2017, Spring 2018, and Summer 2019 across three regions of the eastern and central United States. Included are flight dates, regions, objectives, weather conditions, instrument status, aircraft flight paths, detailed weather reports, and measurement summary figures.

A total of 121 research flights were conducted within the five six-week seasonal campaigns by each of the two instrumented aircraft platforms, the NASA Langley Beechcraft B-200 King Air and the NASA Wallops Flight Facility's C-130 Hercules. During 1,140 flight hours remote and in situ sensors onboard the two research aircraft measured greenhouse gas mole fractions, trace gases, and thermodynamic variables across a variety of continental surfaces and atmospheric conditions to study the transport and fluxes of atmospheric carbon dioxide and methane.

Under “Flight Patterns” note the flights when both aircraft flew directly under Orbiting Carbon Observatory-2 (OCO-2) overpasses to evaluate the ability of OCO-2 to observe high-resolution atmospheric CO₂ variations. The C-130 aircraft was also equipped with active remote sensing instruments for planetary boundary layer height detection and column greenhouse gas measurements.

ACT-America advanced atmospheric greenhouse gas inversions to a high level of accuracy and precision through new methods and models that improved knowledge of atmospheric transport, prior flux models, and space-based observations.

The ACT-America Campaign Catalog provides information about the airborne campaigns of the Atmospheric Carbon and Transport (ACT-America) project. The Catalog compiles flight details for the five campaigns conducted during Summer 2016, Winter 2017, Fall 2017, Spring 2018, and Summer 2019 across three regions of the eastern and central United States. Included are flight dates, regions, objectives, weather conditions, instrument status, aircraft flight paths, detailed weather reports, and measurement summary figures.

A total of 121 research flights were conducted within the five six-week seasonal campaigns by each of the two instrumented aircraft platforms, the NASA Langley Beechcraft B-200 King Air and the NASA Wallops Flight Facility's C-130 Hercules. During 1,140 flight hours remote and in situ sensors onboard the two research aircraft measured greenhouse gas mole fractions, trace gases, and thermodynamic variables across a variety of continental surfaces and atmospheric conditions to study the transport and fluxes of atmospheric carbon dioxide and methane.

Under “Flight Patterns” note the flights when both aircraft flew directly under Orbiting Carbon Observatory-2 (OCO-2) overpasses to evaluate the ability of OCO-2 to observe high-resolution atmospheric CO₂ variations. The C-130 aircraft was also equipped with active remote sensing instruments for planetary boundary layer height detection and column greenhouse gas measurements.

ACT-America advanced atmospheric greenhouse gas inversions to a high level of accuracy and precision through new methods and models that improved knowledge of atmospheric transport, prior flux models, and space-based observations.

Project: ACT-America

The ACT-America, or Atmospheric Carbon and Transport - America, project is a NASA Earth Venture Suborbital-2 mission to study the transport and fluxes of atmospheric carbon dioxide and methane across three regions in the eastern United States. Flight campaigns measured transport of greenhouse gases by continental-scale weather systems. Ground-based measurements of greenhouse gases were also collected. Project goals include better estimates of greenhouse gas sources and sinks which are required for climate management and for prediction of future climate.

Related Datasets:

For a full list of related datasets, see the ACT-America project page at https://daac.ornl.gov/actamerica.

Acknowledgments:

This work was supported by NASA EVS-2 grant number NNX15AG76G. Sandip Pal received funding from ACT-America, grant number 80NSSC19K0730, and support from Texas Tech University to compile this catalog.

Catalog Characteristics

Campaign Spatial Coverage: Eastern and Central United States

Campaign Temporal Coverage: Periodic flights occurred during each intensive campaign

Campaign	Data Beginning and Ending Dates
Summer 2016	2016-05-27 to 2016-08-29
Winter 2017	2017-01-21 to 2017-03-10
Fall 2017	2017-09-22 to 2017-11-13
Spring 2018	2018-03-28 to 2018-05-20
Summer 2019	2019-06-20 to 2019-07-26

 

Campaign Study Area: Latitude and longitude are given in decimal degrees.

Site	Northernmost Latitude	Southernmost Latitude	Easternmost Longitude	Westernmost Longitude
Eastern and Central United States	49.403	27.802	-72.942	-104.237

Campaign Catalog:

The Catalog provides a comprehensive table of information (Figure 1) for the five ACT-America field campaigns, including first, the general flight characteristics:

• dates of research flights (RFs),
• regions covered, prevailing weather conditions,
• flight patterns for both aircraft, and
• status of the instruments.

And second, links to details of the flight and result summaries, including:

• specifics of the RFs and field notes,
• KML images of flight tracks of both aircraft for viewing in GoogleEarth,
• details on the observed weather conditions on the day of RF,
• images of cross-sections of CO₂ mole fractions,
• images of cross-sections of CH₄ mole fractions, and
• images of cross-sections of aerosol backscatter information obtained using the CPL and HALO-HSRL instruments.

 

Table 1. Flight characteristics and descriptions included in the Catalog.

Column Name	Description	User Notes
Date	Date of the research flights (RFs).	Preliminary information for test flights is included in the Instrument/Flight Status column. Test flight days were dedicated to test the status of the aircraft and the instruments deployed. Users should avoid using data for test flights except for research to test instrument potential, calibration, etc.
Region	During the campaigns, sustained airborne C measurements over three source/sink regions were conducted, namely, MA (Mid-Atlantic), MW (Mid-West), and South (Southern region around the Gulf states).	The regions encompass a variety of biomes (Midwest agriculture, Northeast forests, Southeast coastal forests, and agriculture) and oil and gas extraction zones. Each region is large enough to encompass the weather systems that are the target of the project, and the regions encompass a broad range of mid-latitude weather environments. We conducted the RFs by operating out of NASA’s Langley Research Center and NASA’s Wallops Flight Facility for the MA region; Lincoln, Nebraska for the MW region; and Shreveport, Louisiana, for the South region.
Weather Conditions	A brief description of prevailing synoptic weather conditions that are the target for the flight.	Detailed weather reports are provided in the Weather Details column.
Flight Patterns	Flight patterns for both aircraft	Daily flight plans were designed based on prevailing meteorological conditions and source-sink distributions of CO2 and CH4 across the three regions, and the RF days were classified into frontal or fair weather. Some days were hybrids of these. Additionally, during some fair-weather days, under-flights of the Orbiting Carbon Observatory-2 (OCO-2) satellite were carried out to investigate the sensitivity of CO2-column measurements to tropospheric CO2 variability along a > 400 km distance (from south to north).
Instrument/Flight Status	Status of the respective aircraft and instruments.	Most of the RFs were successful without any significant data gaps in the measurements during the campaigns. In Spring 2018 the C-130 encountered some aircraft problem for the first two weeks of deployment over the South region. There were a few instances when instruments had trouble in collecting high-quality measurements. The investigators took care to flag data where some instrumental issues occurred.
More Details	Specifics of the RFs and access to detailed notes.	Link to a Google Drive containing supplementary information about each individual RF, such as in-flight notes and mission manager notes.
Flight Track	KML (Keyhole Markup Language) images of flight tracks of both aircraft on the same day for viewing in GoogleEarth.	Note that all KML flight tracks can be downloaded in a .zip file at the top of the column.
Weather Details	Observed synoptic weather conditions, radar images, precipitation distributions, radiosonde profiles of thermodynamic variables, etc., on the day of the RF are provided in a PDF document.	Note that all weather detail PDF files can be downloaded in a .zip file at the top of the column.
[CO2] cross-sections	Images showing 5-second averaged atmospheric CO2 mole fractions (PICARO) on latitude-versus-altitude and longitude-versus-altitude flight track cross-section frames.	Note that all [CO2] cross-sections image files can be downloaded in a .zip file at the top of the column.
[CH4] cross-sections	Images showing 5-second averaged atmospheric CH4 mole fractions (PICARO) on latitude-versus-altitude and longitude-versus-altitude flight track cross-section frames.	Note that all [CH4] cross-sections image files can be downloaded in a .zip file at the top of the column.
CPL or HALO HSRL	Images containing time-height cross-section of lidar-derived normalized aerosol backscatter field. The images also show the location of aircraft altitude and ground height in m MSL. During the first four field campaigns (i.e., Summer 2016, Winter 2017, Fall 2017, and Spring 2018), the CPL (Cloud Physics Lidar) onboard C-130 was deployed. While during the Summer 2019 field campaign, the HALO-HSRL (High-Spectral Resolution Lidar onboard High Altitude Lidar Observatory) onboard C-130 was deployed.	All lidar-derived normalized aerosol backscatter cross-sections image files can be downloaded in a .zip file at the top of the column.

 

ACT-America, or Atmospheric Carbon and Transport - America, conducted five airborne campaigns across three regions in the eastern United States to study the transport and fluxes of atmospheric carbon. The eastern half of the United States is a region that includes a highly productive biosphere, vigorous agricultural activity, extensive gas and oil extraction and consumption, dynamic, seasonally varying weather patterns and the most extensive carbon cycle and meteorological observing networks on Earth, serves as an ideal setting for the mission.

Each 6-week campaign accurately and precisely quantified anomalies in atmospheric carbon, also known as carbon flux. Accurate carbon flux data is necessary to address all terrestrial carbon cycle science questions. ACT-America addressed the three primary sources of uncertainty in atmospheric inversions—transport error, prior flux uncertainty, and limited data density.

ACT-America advances society’s ability to predict and manage future climate change by enabling policy-relevant quantification of the carbon cycle. Sources and sinks of atmospheric carbon dioxide (CO₂) and methane (CH₄) are poorly known at regional to continental scales. ACT-America enables and demonstrates a new generation of atmospheric inversion systems for quantifying CO₂ and CH4 sources and sinks.

Figure 2. A schematic showing ACT-America mission goals.

ACT-America Goals:

1. To quantify and reduce atmospheric transport uncertainties.
2. To improve regional-scale, seasonal prior estimates of CO₂ and CH₄ fluxes.
3. To evaluate the sensitivity of Orbiting Carbon Observatory (OCO-2) column measurements to regional variability in tropospheric CO₂.

ACT-America achieved these goals by deploying airborne and ground-based platforms to obtain data that were combined with data from existing measurement networks and integrated with an ensemble of atmospheric inversion systems. Aircraft instrumented with remote and in-situ sensors observed how mid-latitude weather systems interact with CO₂ and CH₄ sources and sinks to create atmospheric CO₂/CH₄ distributions. A model ensemble consisting of a mesoscale atmospheric transport model with multiple physics and resolutions options nested within global inversion models and surface CO₂/CH₄ flux ensembles was used to predict atmospheric CO₂ and CH₄ distributions.

Beyond the conclusion of the mission, the application of knowledge gained from this mission will improve diagnoses of the carbon cycle across the globe for decades.

Refer to the documentation for each individual data product for quality assessment information.

ACT-America Overview

ACT-America deployed the NASA C-130 and B-200 aircraft to measure atmospheric CO₂ and CH₄ in the atmospheric boundary layer (ABL) and free troposphere (FT). In all five seasonal campaigns, a total of 121 days of research flights, more than 1,140 hours of observations, 570 level legs, and 1,363 vertical profiles were conducted. Flights concentrated observations on three study domains: Northeast, South-central, and Midwest. These flights were dedicated in a roughly 3:3:1 ratio among fair weather, stormy weather, and OCO-2 underpass flight patterns (Crisp et al., 2004, Crisp et al., 2008).

For fair and stormy weather flights, the C-130 flew at 3–8 km above ground, collecting in-situ measurements in the lower FT, remotely sensed, column-averaged CO₂ measurements focused on the ABL, and occasional in-situ vertical profiles. The B-200 primarily sampled the ABL. For OCO-2 under flights, the C-130 flew at 8 km above ground with the B-200 flying in the ABL, both along the OCO-2 flight track. The existing in situ tower CO₂/CH₄ observing network was enhanced with five additional tower sites.

The mission delivered 2-3 times more high-quality lower tropospheric CO₂ and CH₄ observations than any previous airborne campaign.

ACT-America Instruments

ACT-America deployed high-quality, field-tested (TRL-8 (Technology Readiness Level) or higher) trace gas and meteorological instruments. The mix of remote and in situ sensors enabled extensive spatial coverage of key variables. The C-130 instruments included the Multi-Functional Fiber Laser Lidar for CO₂ columns, range to ground and surface reflectance; the Cloud Physics Lidar for ABL (Atmospheric boundary layer) depths and atmospheric aerosols; Picarro cavity ring-down spectrometers for in situ CO₂, CH₄, water vapor, and carbon monoxide (CO); 2B Technologies for in situ ozone; Flasks for CO₂, CH₄, CO, carbonyl sulfide, and ¹⁴CO₂; and an environmental suite for in situ pressure, temperature and winds. The UC-12 had the same in situ sensors save for winds. Towers utilize Picarro for in situ CO₂ and CH₄.

For more information on the instruments used during the ACT-America campaign refer to the documentation for each individual data product.

Crisp, D., R. M. Atlas, F.-M. Breon, L. R. Brown, J. P. Burrows, P. Ciais, B. J. Connor, S. C. Doney, I. Y. Fung, D. J. Jacob, C. E. Miller, D. O’Brien, S. Pawson, J. T. Randerson, P. Rayner, R. J. Salawitch, S. P. Sander, B. Sen, G. L. Stephens, P. P. Tans, G. C. Toon, P. O. Wennberg, S. C. Wofsy, Y. L. Yung, Z. Kuang, B. Chudasama, G. Sprague, B. Weiss, R. Pollock, D. Kenyon, and S. Schroll. 2004. The Orbiting Carbon Observatory (OCO) mission. Advances in Space Research 34:700–709. https://doi.org/10.1016/j.asr.2003.08.062

Crisp, D. 2008. NASA Orbiting Carbon Observatory: measuring the column averaged carbon dioxide mole fraction from space. Journal of Applied Remote Sensing 2:023508. https://doi.org/10.1117/1.2898457