VAP : Shortwave Flux Analysis (SWFLUXANAL)

Instrument Categories
Radiometric, Cloud Properties

The SW (shortwave) Flux Analysis VAP applies a clear-sky detection and fitting technique (Long and Ackerman 2000) to data from broadband SW radiometers located at the Southern Great Plains site. This technique uses hemispheric, broadband total- and diffuse-shortwave irradiance measurements to identify clear-sky periods using the known characteristics of typical clear-sky irradiance time series. These clear-sky estimates are then used to infer the effect of cloudiness on the measured downwelling SW at 1-minute resolution for daylight hours. The 1-minute resolution analysis also includes data quality assessment that goes beyond standard min/max/delta and component comparison testing. The SW Flux Analysis VAP also uses a technique (Long et al. 1999) to infer average fractional sky cover at 15-minute resolution for solar elevation angles 10° or greater.

For more details, see http://science.arm.gov/vaps/swflux.stm.

Output Products

15swfanalbrs1long : Short Wave Flux Analysis: 15-min resolution on BRS data, Long algorithm
15swfanalsiros1long : Short Wave Flux Analysis: 15-min resolution on SIROS data, Long algorithm
15swfanalsirs1long : Short Wave Flux Analysis: 15-min resolution on SIRS data, Long algorithm
15swfanalskyrad1long : Short Wave Flux Analysis: 15-min resolution on SKYRAD data, Long algorithm
15swfcldfac1long : Fractional cloud cover, clear-sky and all-sky shortwave flux for each of 25 individual SGP facilities.
1swfanalbrs1long : Short Wave Flux Analysis: 1-min resolution on BRS data, Long algorithm
1swfanalsiros1long : Short Wave Flux Analysis: 1-min resolution on SIROS data, Long algorithm
1swfanalsirs1long : Short Wave Flux Analysis: 1-min resolution on SIRS data, Long algorithm
1swfanalskyrad1long : Short Wave Flux Analysis: 1-min resolution on SKYAD data, Long algorithm

Primary Measurements

The following measurements are those considered scientifically relevant.

Locations

North Slope Alaska (NSA)
- Central Facility, Atqasuk AK (C2)
- Central Facility, Barrow AK (C1)
Southern Great Plains (SGP)
- Ashton, KS (E9)
- Byron, OK (E11)
- Central Facility, Lamont, OK (C1)
- Coldwater, KS (E8)
- Cordell, OK (E22)
- Cyril, OK (E24)
- Earlsboro, OK (E27)
- El Reno, OK (E19)
- Elk Falls, KS (E7)
- Halstead, KS (E5)
- Hillsboro, KS (Extended) (E2)
- Lamont, OK (Extended) (E13)
- Larned, KS (E1)
- LeRoy, KS (E3)
- Meeker, OK (Extended) (E20)
- Morris, OK (Extended) (E18)
- Okmulgee, OK (E21)
- Pawhuska, OK (E12)
- Plevna, KS (E4)
- Ringwood, OK (E15)
- Seminole, OK (E25)
- Southern Great Plains Network (N1)
- Towanda, KS (E6)
- Tyro, KS (E10)
- Vici, OK (Extended) (E16)
Tropical Western Pacific (TWP)
- Central Facility, Darwin, Australia (C3)
- Central Facility, Manus I., PNG (C1)
- Central Facility, Nauru Island (C2)