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Dataset Overview | National Centers for Environmental Information (NCEI)

N Summary from the United States Air Force

N Summary

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N Summaries are means and percentage frequency tabulations for stations around the world. There are approximately 2674 worldwide stations with five or more years data for which the N Summary was prepared. The summaries were calculated using surface weather observations collated by the United States Air Force. The parameters in an N Summary are one or more of the following monthly, seasonal, and annual tabulations: 1. Percentage frequency of surface winds (kts) by day, hour and month, to 16 points of the compass, 2. Percentage frequency of surface winds (kts) (seasonal and annual) to 16 points of the compass, 3. Precipitation amounts (in.), 4. Mean frequency of daily maximum temperature (Deg. F), mean maximum, and extreme maximum temperature (Deg. F), 5. Mean frequency of daily minimum temperature (Deg. F), mean minimum and extreme minimum temperature (Deg. F), and mean daily temperature range (Deg. F), 6. Mean number of days favorable for indicated military operations, 7. Miscellaneous data; mean number of days of occurrence of various weather phenomena, 8. Mean number of days with indicated total and low cloud amounts (oktas), 9. Percentage frequency of observations with low clouds (amount in 8ths, height in feet) and visibility (miles) reported, 10. Relative humidity means, 11. Percentage frequency distribution of wind speed (kts) and temperature (Deg. F), 12. Percentage frequency of visibility (miles) and various atmospheric phenomena, 13. Mean number of days with specified phenomena, 14. Mean cloudiness (%), 15. Snow depth (in.), 16. Percentage frequency of surface winds (kts) to 8 points of the compass (monthly), 17. Percentage frequency of surface winds (kts) to 8 points of the compass/ seasonal, 18. Sea level pressure (mb), means, and standard deviations. Some of the tabulations are for all hours of the day while others may be for each 3-hourly, 6-hourly, or 12-hourly segment of the day, and in some cases, for only one observation a day.
  • Cite this dataset when used as a source.
  • NCEI Physical Archive Collection: NSUM
  • gov.noaa.ncdc:C00130
gov.noaa.ncdc:C00130
Distribution Formats
  • XML
  • Microfilm / Paper
Ordering Instructions Contact NCEI for other distribution options and instructions.
Distributor NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Dataset Point of Contact Customer Engagement Branch
NOAA National Centers for Environmental Information
1-828-271-4800
ncei.orders@noaa.gov
Time Period 1890-01-01 to 1978-12-31
Spatial Bounding Box Coordinates
West: -180.0
East: 180.0
South: -90.0
North: 90.0
Spatial Coverage Map
General Documentation
Publication Dates
  • publication: 1974
Data Presentation Form Hardcopy image - image archived in analog format
Dataset Progress Status Historical archive - data has been stored in an offline storage facility
Data Update Frequency Not planned
Purpose N Summaries were used to summarize the climates of various cities and countries around the world. These climatic summaries could be used in a wide variety of national and international decisions.
Dataset Citation
  • Cite this dataset when used as a source.
Cited Authors
  • DOD/USAF/AFCCC > Air Force Combat Climatology Center, U.S. Air Force, U.S. Department of Defense
  • Environmental Technical Application Center
Originators
  • DOD/USAF/AFCCC > Air Force Combat Climatology Center, U.S. Air Force, U.S. Department of Defense
  • Environmental Technical Application Center
Publishers
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
Theme keywords Global Change Master Directory (GCMD) Science Keywords
  • Earth Science > Atmosphere > Air Quality > Visibility
  • Earth Science > Atmosphere > Atmospheric Phenomena
  • Earth Science > Atmosphere > Atmospheric Pressure > Atmospheric Pressure Measurements
  • Earth Science > Atmosphere > Atmospheric Pressure > Sea Level Pressure
  • Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Air Temperature
  • Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Maximum/Minimum Temperature
  • Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Temperature Anomalies
  • Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Humidity
  • Earth Science > Atmosphere > Atmospheric Winds > Surface Winds
  • Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Frequency
  • Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Ceiling
  • Earth Science > Atmosphere > Precipitation > Precipitation Amount
  • Earth Science > Atmosphere > Precipitation > Liquid Precipitation > Rain
  • Earth Science > Atmosphere > Precipitation > Solid Precipitation > Snow
  • Earth Science > Cryosphere > Snow/Ice > Snow Depth
  • Earth Science > Terrestrial Hydrosphere > Snow/Ice > Snow Depth
Global Climate Observing System (GCOS) Essential Climate Variables (ECVs)
  • Atmospheric - Surface - Precipitation
  • Atmospheric - Surface - Air Temperature
  • Atmospheric - Surface - Wind Speed And Direction
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords
  • DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
Platform keywords Global Change Master Directory (GCMD) Platform Keywords
  • Fixed Observation Stations
Instrument keywords Global Change Master Directory (GCMD) Instrument Keywords
  • Thermometers
  • Snow Measuring Rod
  • Rain Gauges
  • Barometers
  • Visual Observations
Place keywords Global Change Master Directory (GCMD) Location Keywords
  • Geographic Region > Global Land
Stratum keywords Global Change Master Directory (GCMD) Location Keywords
  • Vertical Location > Land Surface
  • Vertical Location > Troposphere
  • Vertical Location > Stratosphere
Use Constraints
  • Cite this dataset when used as a source.
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Access Constraints
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Fees
  • In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Lineage Statement N Summaries were prepared by the U.S. Air Force Combat Climatology Center (AFCCC) and its predecessor, the Environmental Technical Application Center.
Source Datasets
  • Integrated Surface Global Hourly Data
    • Integrated Surface Global Hourly Data
      Many surface weather observations collected by the United States Air Force have been integrated into the Integrated Surface Global Hourly Database.
    • Description of Source: Many of the observations that were used to calculate the N Summaries can also be found in the Integrated Surface Database. The Air Force does not provide public access to this data directly.
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Last Modified: 2023-09-07
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