AC4 Research priorities and funding opportunities

AC4 is a competitive research program, which solicits research proposals typically on an annual basis, starting with the FY2013 announcement released during summer of 2012. In addition, occasionally, the program participates in an interagency call for proposals. Current and past solicitations and research priorities are listed below.

View past AC4 funding opportunities (and those of predecessor programs) below.

Fiscal year 2020 competition

AC4 FY20 Competition Information Sheet

In FY20, to continue and expand its investments in the urban atmosphere, the AC4 program invites proposals focused on one or more of the following:

  • Research that builds on previously developed resources, e.g. CO2-USA network, or existing infrastructure to analyze or otherwise explore in depth recently studied cities across the United States
  • Multispecies approach to understanding the urban environment
  • Research with the potential to inform mitigation strategies, especially with regard to co- benefits for air pollution and greenhouse gas reduction
  • Participation in upcoming field efforts in U.S. cities or exploration of novel chemistry and tracers of urban air, although an FY21 solicitation for field efforts is also anticipated
  • Investigation of the evolution of urban air composition in a warming climate

Fiscal year 2019 competition

AC4 FY19 Competition Information Sheet

In FY19, the AC4 Program in NOAA's Climate Program Office solicits proposals that aim to explain various trends, patterns and extremes detectable in the existing long-term observational records.

Features that could be explored include, but are not limited to:

  • Factors influencing gradient of the long-term trends
  • Patterns, anomalies and extremes in long-term trends
  • Intra-and-interannual variability and change
  • Changes in amplitude of seasonal cycle
  • Local or regional changes in the long-term trends

AC4 FY19 Competition Awards

Fiscal year 2018 competition

AC4 FY18 Competition Information Sheet

In FY18, as part of a continuing interest in the nitrogen cycle, the Atmospheric Chemistry, Carbon Cycle and Climate (AC4) program announcement focuses on laboratory, modeling, and analysis studies (of existing field data) that address one or more of the following priorities:
1. Investigate the mechanisms of BVOC oxidation involving reactive nitrogen species in yielding organic nitrogen aerosols and/or their role in NOx removal.
2. Perform complementary chamber and/or laboratory studies to better constrain NO3- BVOC reaction mechanisms and organic aerosol formation.
3. Use relevant satellite products or develop new ones (e.g. formaldehyde), particularly from SNPP/JPSS-1 and their predecessors.

AC4 FY18 Competition Awards

Fiscal year 2017 competition

AC4 FY17 Competition Information Sheet

The FY17 AC4 announcement builds on the wealth of collected atmospheric measurements of emissions from oil & gas sector, as well as a number of studies focused on emissions from urban regions to support synthesis efforts, including analysis and modeling of emissions and chemistry. Multi PI projects synthesizing several aspects of a particular geographical region or those which involve a synthesis across several geographical regions with common science objectives are solicited.

FIREX-related awards made in 2017 (#11-20)

Fiscal year 2016 competition 

AC4 FY16 Competition Information Sheet

In FY16, AC4 program solicits proposals focused on Western US fire research relevant to FIREX. Specifically, AC4 plans to support the types of projects that:
1. Collect, analyze and/or model data from FIREX or related field or laboratory experiments
2. Exploit multiple data sets - in situ, remote, and /or satellite, especially from CrIS instrument
3. Focus on the effects of biomass burning on nitrogen cycle
4. Contribute to improving the prediction of smoke from wildfires, especially in NOAA’s Air Quality Forecasting system, via improvements to regional prediction modeling systems that utilize models like CMAQ and WRF-Chem.

FIREX-related awards made in 2016 (#1-10)

Fiscal year 2015 competition

AC4 FY15 Competition Information Sheet

In FY15, AC4 program solicited proposals focused on
1. Improvements to nitrogen cycle representation in GFDL's Earth System Models.

Fiscal Year 2014 competitions

AC4 FY14 Competition Information Sheet

In FY14, AC4 program solicited proposals targeting research areas including
1. Emissions from Southeast of US
2. Emissions from oil & gas extraction
3. Deposition processes

Interagency carbon cycle call for proposals (under NASA ROSES)

In the carbon cycle interagency call for proposals under NASA/ROSES, NOAA's participation in (through our AC4 program) focused on "Carbon dynamics within urban-suburban-forested-agricultural landscapes". The full solicitation included other topics within carbon cycle. 

The link to the solicitation is the following:

Awards made in 2014

Fiscal Year 2013 competition

AC4 FY13 Competition Information Sheet  

In FY13, AC4 program solicited proposals targeting research areas including
1. Emissions from urban areas and oil & gas extraction
2. Improvements to CarbonTracker
3. Nitrogen cycle

18 projects were awarded, 40% success rate

Awards made in 2013

Fiscal Year 2012 competitions

ACC and GCC FY12 Information Sheets (Competition cancelled, no awards were made)

1. Nitrogen cycle

1. Improvements to CarbonTracker
2. Carbon emissions from urban areas
3. Analysis of biogeochemical feedbacks in CMIP5

Fiscal Year 2011 competitions

ACC and GCC FY11 Information Sheets

1. Analysis of CalNex field measurements
2. Formation and transformation of ice nuclei

1. Causes of variability in sources and sinks
2. Future atmospheric carbon dioxide concentrations
3. Ocean carbon cycling, biogeochemical and ecosystem dynamics


Contact AC4

Dr. Monika Kopacz (UCAR)
Program manager, Atmospheric Chemistry, Carbon Cycle and Climate (AC4)
P: (301) 734-1208


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