A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes
[1] The accuracy of two empirical formulae used in recent climatological studies to estimate the atmospheric longwave flux at the ocean surface from ship meteorological reports has been evaluated using research cruise measurements from the northeast Atlantic. The measurements were obtained with a py...
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ftnerc:oai:nora.nerc.ac.uk:101335 2023-05-15T17:41:35+02:00 A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes Josey, S.A. Pascal, R.W. Taylor, P.K. Yelland, M.J. 2003-04 http://nora.nerc.ac.uk/id/eprint/101335/ https://doi.org/10.1029/2002JC001418 unknown Josey, S.A. orcid:0000-0002-1683-8831 Pascal, R.W.; Taylor, P.K.; Yelland, M.J. orcid:0000-0002-0936-4957 . 2003 A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes. Journal of Geophysical Research C (Oceans), 108 (C4). 03108-[16pp]. https://doi.org/10.1029/2002JC001418 <https://doi.org/10.1029/2002JC001418> Publication - Article PeerReviewed 2003 ftnerc https://doi.org/10.1029/2002JC001418 2023-02-04T19:33:29Z [1] The accuracy of two empirical formulae used in recent climatological studies to estimate the atmospheric longwave flux at the ocean surface from ship meteorological reports has been evaluated using research cruise measurements from the northeast Atlantic. The measurements were obtained with a pyrgeometer and corrected for differential heating of the pyrgeometer dome and shortwave transmission through the dome. The formulae tested were from Clark et al. [1974] and Bignami et al. [1995]; neither was capable of providing consistently reliable estimates of the longwave flux. Clark overestimated the mean measured longwave of 341.1 Wm(-2) by 11.7 Wm(-2), while Bignami underestimated by 12.1 Wm(-2). A new formula is developed that expresses the effects of cloud cover and other parameters on the longwave through an adjustment to the measured air temperature. The air temperature is adjusted by the amount necessary to obtain the effective temperature of a blackbody with a radiative flux equivalent to that from the atmosphere. A simple parameterization of the adjustment in terms of the total cloud amount gives longwave estimates that have an improved mean bias error with respect to the measurements of -1.3 Wm(-2). The new formula is still biased under overcast, low cloud base conditions. However, by including a dependence on dew point depression in the formula, this bias is resolved, and the mean error reduced to 0.2 Wm(- 2). The new formula has been tested using measurements made on two subsequent cruises and found to agree to within 2 Wm(-2) in the mean at middle-high latitudes Article in Journal/Newspaper Northeast Atlantic Natural Environment Research Council: NERC Open Research Archive Dome The ENVELOPE(166.000,166.000,-85.367,-85.367) Journal of Geophysical Research 108 C4 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
[1] The accuracy of two empirical formulae used in recent climatological studies to estimate the atmospheric longwave flux at the ocean surface from ship meteorological reports has been evaluated using research cruise measurements from the northeast Atlantic. The measurements were obtained with a pyrgeometer and corrected for differential heating of the pyrgeometer dome and shortwave transmission through the dome. The formulae tested were from Clark et al. [1974] and Bignami et al. [1995]; neither was capable of providing consistently reliable estimates of the longwave flux. Clark overestimated the mean measured longwave of 341.1 Wm(-2) by 11.7 Wm(-2), while Bignami underestimated by 12.1 Wm(-2). A new formula is developed that expresses the effects of cloud cover and other parameters on the longwave through an adjustment to the measured air temperature. The air temperature is adjusted by the amount necessary to obtain the effective temperature of a blackbody with a radiative flux equivalent to that from the atmosphere. A simple parameterization of the adjustment in terms of the total cloud amount gives longwave estimates that have an improved mean bias error with respect to the measurements of -1.3 Wm(-2). The new formula is still biased under overcast, low cloud base conditions. However, by including a dependence on dew point depression in the formula, this bias is resolved, and the mean error reduced to 0.2 Wm(- 2). The new formula has been tested using measurements made on two subsequent cruises and found to agree to within 2 Wm(-2) in the mean at middle-high latitudes |
format |
Article in Journal/Newspaper |
author |
Josey, S.A. Pascal, R.W. Taylor, P.K. Yelland, M.J. |
spellingShingle |
Josey, S.A. Pascal, R.W. Taylor, P.K. Yelland, M.J. A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
author_facet |
Josey, S.A. Pascal, R.W. Taylor, P.K. Yelland, M.J. |
author_sort |
Josey, S.A. |
title |
A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
title_short |
A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
title_full |
A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
title_fullStr |
A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
title_full_unstemmed |
A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
title_sort |
new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes |
publishDate |
2003 |
url |
http://nora.nerc.ac.uk/id/eprint/101335/ https://doi.org/10.1029/2002JC001418 |
long_lat |
ENVELOPE(166.000,166.000,-85.367,-85.367) |
geographic |
Dome The |
geographic_facet |
Dome The |
genre |
Northeast Atlantic |
genre_facet |
Northeast Atlantic |
op_relation |
Josey, S.A. orcid:0000-0002-1683-8831 Pascal, R.W.; Taylor, P.K.; Yelland, M.J. orcid:0000-0002-0936-4957 . 2003 A new formula for determining the atmospheric longwave flux at the ocean surface at mid-high latitudes. Journal of Geophysical Research C (Oceans), 108 (C4). 03108-[16pp]. https://doi.org/10.1029/2002JC001418 <https://doi.org/10.1029/2002JC001418> |
op_doi |
https://doi.org/10.1029/2002JC001418 |
container_title |
Journal of Geophysical Research |
container_volume |
108 |
container_issue |
C4 |
_version_ |
1766143218319097856 |