Light profile data set for NSF Photochemistry project on the North Slope of Alaska.


Data file containing the irradiance profile with depth in two rivers on the North Slope of Alaska near Toolik Lake . Variables include site, depth, and wavelength. A synthesis of the data presented here is published in Cory et al. 2013, PNAS 110:3429-3434, and in Cory et al. 2014, Science 345:925-928.

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Published on EDI/LTER Data Portal


Kling, G., Cory, R. 2014. Light profile data set for NSF Photochemistry project on the North Slope of Alaska. Environmental Data Initiative.

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Wednesday, June 29, 2011 to Friday, June 22, 2012

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Light profiles in the water column of streams and lakes were measured as irradiance with depth using a compact optical profiling system (C-OPS; Biospherical, Inc.). All profiles were collected between 09:00-14:00 local time (Alaska Standard Time). A dark profile was collected before all light profiles by leaving the cover on the COPS and taking measurements above the water column. Following collection of the dark profile, the depth was tared to zero m by placing the C-OPS into the water with the sensor just above the surface of the water and tarring to "0 m" in the software. An aircast at the water surface was collected for 15-20 seconds before deploying the C-OPS into the water column where it collected irradiance data with depth as it descenced through the water column. During the descent pitch and roll were monitored to remain within +/- 5 degrees.

Cory, R.M., C.P. Ward, B.C Crump, G. W. Kling. 2014. Sunlight controls water column processing of carbon in arctic fresh waters. Science, 10.1126/science.1253119

Cory, R. M., B.C. Crump, J.A. Dobkowski, G.W. Kling. 2013. Surface exposure to sunlight stimulates CO2 release from permafrost soil carbon in the Arctic. Proc. Nat. Acad. Sci. 110 (9) 3429-3434, doi: 10.1073/pnas.1214104110

Field and Lab Methods & Protocols

Version Changes: 

December 2014: Created this file, version .01
Version 2: Katie updated the decimal points for the data. 12Dec2014

Sites sampled.

Full Metadata and data files (either comma delimited (csv) or Excel) - Environmental Data Initiative repository.

Use of the data requires acceptance of the data use policy --> Arctic LTER Data Use Policy