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[TXT]NSAC1_mean_fluxes.txt 2009-03-20 18:22 31K 
[TXT]NSAC2_mean_fluxes.txt 2009-03-20 18:22 31K 

NSA Radiation Data-

This page is intended to be used for gathering data metrics only. If you are trying to order current data, please login through the following link:

Browse and Order ARM QCRad Data

NSA Barrow Radiation Data

Observations from a suite of radiometers including Precision Spectral Pyranometers (PSPs), Precision Infrared Radiometers (PIRs), and a Normal Incident Pyrheliometer (NIP) are combined with surface meteorological instruments using the Quality Control of Radiation (QCRad) value added product (Long and Shi 2008, Long and SHi 2006) to assess data quality and produce a continuous time series of broadband radiative flux measurements. The QCRad methodology uses climatological analyses of the surface radiation measurements to define reasonable limits for testing the data for unusual data values and produces best estimates of observed radiative fluxes. The methodology not only sets standard maximum and minimum value limits, but includes many cross-comparisons based on what the ARM program has learned about how these instruments behave in the field. The data for all of 2008, as well as additional years of data at NSA, have been processed and are available in the ARM archive.

Additional information are available in the 2nd Quarter 2009 science metric report at>.

Data Streams

Two netcdf files are produced daily for the QCRad VAP and are available in the ARM archive. The first file is a c1 level file which contains radiation measurement fields and the bit-packed quality control (QC) information associated with each field. The summary netcdf file (.s1) contains the same radiation measurement fields with simplified QC information and is the recommended ARM surface radiation file for the general user.

The files in this directory, time series of daily (24-hour average) fluxes, were derived from the QCRad VAP products and have been produced for the 2008 data at Barrow and Atqasuk for model evaluation. For the 24-hour averages, negative values of shortwave flux (possibly due to thermal offsets) were set to zero before averaging. Missing data is indicated by -9999.

The columns of these data files are as follows:

  1. Day of year, 2008
  2. Best estimate global shortwave (GSW) downwelling flux (W/m2)
  3. Diffuse downwelling shortwave flux (W/m2)
  4. Direct normal shortwave flux (W/m2)
  5. Downwelling longwave flux (W/m2)
  6. Upwelling longwave flux (W/m2)
  7. Upwelling shortwave flux (W/m2)


Long, C. N. and Y. Shi, (2006): The QCRad Value Added Product: Surface Radiation Measurement Quality Control Testing, Including Climatologically Configurable Limits, Atmospheric Radiation Measurement Program Technical Report, ARM TR-074, 69 pp. Available via

Long, C. N., and Y. Shi, (2008): An Automated Quality Assessment and Control Algorithm for Surface Radiation Measurements, TOASJ, 2, 23-37, doi: 10.2174/1874282300802010023.

Contact Information

Infrastructure Translator
Sally McFarlane

Yan Shi

Science Sponsor
Chuck Long