Calibrated digital images of Campbell-Stokes recorder card archives for direct solar irradiance studies

Research output: Contribution to journalArticle

Standard

Calibrated digital images of Campbell-Stokes recorder card archives for direct solar irradiance studies. / Horseman, A.M.; Richardson, T.; Boardman, A.T.; Tych, W.; Timmis, R.; MacKenzie, A.R.

In: Atmospheric Measurement Techniques, Vol. 6, No. 5, 01.01.2013, p. 1371-1379.

Research output: Contribution to journalArticle

Harvard

APA

Vancouver

Author

Horseman, A.M. ; Richardson, T. ; Boardman, A.T. ; Tych, W. ; Timmis, R. ; MacKenzie, A.R. / Calibrated digital images of Campbell-Stokes recorder card archives for direct solar irradiance studies. In: Atmospheric Measurement Techniques. 2013 ; Vol. 6, No. 5. pp. 1371-1379.

Bibtex

@article{36cbbb374bba427486ed543ba920866b,
title = "Calibrated digital images of Campbell-Stokes recorder card archives for direct solar irradiance studies",
abstract = "A systematic, semi-automatic method for imaging the cards from the widely used Campbell-Stokes sunshine recorder is described. We show how the application of inexpensive commercial equipment and practices can simply and robustly build an archive of high-quality card images and manipulate them into a form suitable for easy further analysis. Rectified and registered digital images are produced, with the card's midday marker in the middle of the longest side, and with a temporal scaling of 150 pixels per hour. The method improves on previous, mostly manual, analyses by simplifying and automating steps into a process capable of handling thousands of cards in a practical timescale. A prototype method of extraction of data from this archive is then tested by comparison with records from a co-located pyrheliometer at a resolution of the order of minutes. The comparison demonstrates that the Campbell-Stokes recorder archive contains a time series of downwelling solar-irradiance-related data with similar characteristics to that of benchmark pyrheliometer data from the Baseline Surface Radiation Network. A universal transfer function for card burn to direct downwelling short-wave radiation is still some way off and is the subject of ongoing research. Until such time as a universal transfer function is available, specific functions for extracting data in particular circumstances offer a useful way forward. The new image-capture method offers a practical way to exploit the worldwide sets of long-term Campbell-Stokes recorder data to create a time series of solar irradiance and atmospheric aerosol loading metrics reaching back over 100 yr from the present day.",
author = "A.M. Horseman and T. Richardson and A.T. Boardman and W. Tych and R. Timmis and A.R. MacKenzie",
year = "2013",
month = jan
day = "1",
doi = "10.5194/amt-6-1371-2013",
language = "English",
volume = "6",
pages = "1371--1379",
journal = "Atmos. Meas. Tech. Discuss",
issn = "1867-1381",
publisher = "European Geosciences Union",
number = "5",

}

RIS

TY - JOUR

T1 - Calibrated digital images of Campbell-Stokes recorder card archives for direct solar irradiance studies

AU - Horseman, A.M.

AU - Richardson, T.

AU - Boardman, A.T.

AU - Tych, W.

AU - Timmis, R.

AU - MacKenzie, A.R.

PY - 2013/1/1

Y1 - 2013/1/1

N2 - A systematic, semi-automatic method for imaging the cards from the widely used Campbell-Stokes sunshine recorder is described. We show how the application of inexpensive commercial equipment and practices can simply and robustly build an archive of high-quality card images and manipulate them into a form suitable for easy further analysis. Rectified and registered digital images are produced, with the card's midday marker in the middle of the longest side, and with a temporal scaling of 150 pixels per hour. The method improves on previous, mostly manual, analyses by simplifying and automating steps into a process capable of handling thousands of cards in a practical timescale. A prototype method of extraction of data from this archive is then tested by comparison with records from a co-located pyrheliometer at a resolution of the order of minutes. The comparison demonstrates that the Campbell-Stokes recorder archive contains a time series of downwelling solar-irradiance-related data with similar characteristics to that of benchmark pyrheliometer data from the Baseline Surface Radiation Network. A universal transfer function for card burn to direct downwelling short-wave radiation is still some way off and is the subject of ongoing research. Until such time as a universal transfer function is available, specific functions for extracting data in particular circumstances offer a useful way forward. The new image-capture method offers a practical way to exploit the worldwide sets of long-term Campbell-Stokes recorder data to create a time series of solar irradiance and atmospheric aerosol loading metrics reaching back over 100 yr from the present day.

AB - A systematic, semi-automatic method for imaging the cards from the widely used Campbell-Stokes sunshine recorder is described. We show how the application of inexpensive commercial equipment and practices can simply and robustly build an archive of high-quality card images and manipulate them into a form suitable for easy further analysis. Rectified and registered digital images are produced, with the card's midday marker in the middle of the longest side, and with a temporal scaling of 150 pixels per hour. The method improves on previous, mostly manual, analyses by simplifying and automating steps into a process capable of handling thousands of cards in a practical timescale. A prototype method of extraction of data from this archive is then tested by comparison with records from a co-located pyrheliometer at a resolution of the order of minutes. The comparison demonstrates that the Campbell-Stokes recorder archive contains a time series of downwelling solar-irradiance-related data with similar characteristics to that of benchmark pyrheliometer data from the Baseline Surface Radiation Network. A universal transfer function for card burn to direct downwelling short-wave radiation is still some way off and is the subject of ongoing research. Until such time as a universal transfer function is available, specific functions for extracting data in particular circumstances offer a useful way forward. The new image-capture method offers a practical way to exploit the worldwide sets of long-term Campbell-Stokes recorder data to create a time series of solar irradiance and atmospheric aerosol loading metrics reaching back over 100 yr from the present day.

UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84882792545&partnerID=8YFLogxK

U2 - 10.5194/amt-6-1371-2013

DO - 10.5194/amt-6-1371-2013

M3 - Article

AN - SCOPUS:84882792545

VL - 6

SP - 1371

EP - 1379

JO - Atmos. Meas. Tech. Discuss

JF - Atmos. Meas. Tech. Discuss

SN - 1867-1381

IS - 5

ER -