Tropospheric Chemistry: Measurements

Datasets for Modellers

Created to improve the ability to incorporate NOAA WP-3D airborne chemistry data sets into large-scale models. Provided ICARTT-formatted data files from all the major chemically-instrumented NOAA WP-3D aircraft field projects since 1999. There are three data files for each flight day:

  1. First file contains one-minute averages of faster-response (typically 1Hz) meteorological, gas-phase, and particulate-phase data for a given flight.
  2. Second file contains these faster-response data averaged over the whole air sampler (WAS) open/close times for a given flight.
  3. Third file contains the WAS data on hydrocarbons, halocarbons, and other trace species.

Each project website contains more information and details of the specific measurements. As a convenience, each of the file types are put together into a single .tar file and embedded in the 'Modellers data download'. Additional data files (IGOR format, individual data files - not specifically for modellers) are available from the specific experiment websites.

map of major aircraft missions

Major aircraft field campaigns

2010 CalNex (California Nexus Research at the Nexus of Air Quality and Climate Change) based in Ontario, California during May - June 2010.

2008 ARCPAC (Aerosol, Radiation, and Cloud Processes affecting Arctic Climate) based in Fairbanks, Alaska during March - April 2008.

2006 TexAQS (Texas Air Quality Study) based in Houston, Texas during Sept-Oct, 2006.

2004 NEAQS-ITCT (New England Air Quality - International Transport and Chemical Transformation) based in Portsmouth, New Hampshire during 5 July - 15 August 2004.

2002 ITCT (Intercontinental Transport and Chemical Transformation) based in Monterey, CA during April - May 2002.

2000 TexAQS (Texas Air Quality Study) based in Houston, Texas during August - September 2000.

1999 SOS (Southern Oxidants Study) based in Nashville, Tennessee during June - July 1999.

Calculation of the averages

When calculating the averages for both data sets, there is no requirement for the minimum number of valid points in that average, to be consistent with how NASA calculates their merge files. Also, after talking to different PIs, there was no optimum number of points to require since under different conditions (plumes, altitudes, etc.) there would be different numbers of points to get a representative average for different measurements.