Details

Autor(en) / Beteiligte

• Yang, M
• Bell, T. G
• Hopkins, F. E
• Kitidis, V
• Cazenave, P. W
• Nightingale, P. D
• Yelland, M. J
• Pascal, R. W
• Prytherch, J
• Brooks, I. M
• Smyth, T. J

Titel

Air-Sea Fluxes of CO.sub.2 and CH.sub.4 from the Penlee Point Atmospheric Observatory on the South West Coast of the UK

Ist Teil von

• Atmospheric chemistry and physics, 2016-01, Vol.2016 (1), p.1

Ort / Verlag

Copernicus GmbH

Erscheinungsjahr

2016

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• We present air-sea fluxes of carbon dioxide (CO.sub.2 ), methane (CH.sub.4 ), momentum, and sensible heat measured by the eddy covariance method from the recently established Penlee Point Atmospheric Observatory (PPAO) on the South West coast of the United Kingdom. Measurements from the southwest direction (background marine air) at three different sampling heights (approximately 15, 18, 27 m above mean sea level, AMSL) in three different periods during 2014-2015 are shown. At sampling heights ≥ 18 m AMSL, measured fluxes of momentum and sensible heat demonstrate reasonable agreement with their expected transfer rates over the open ocean. This confirms the suitability of PPAO for air-sea exchange measurements. We observed reductions in the air-to-sea fluxes of CO.sub.2 from spring to summer in both years, which coincided with the breakdown of the spring phytoplankton bloom. At all sampling heights, mean CH.sub.4 fluxes were positive, suggesting marine emissions. Higher CH.sub.4 fluxes were observed during rising tides (20 3; 29 6; 38 3 μmole m.sup.−2 d.sup.−1 at 15, 27, 18 m AMSL) than during falling tides (14 2; 21 5; 22 2 μmole m.sup.−2 d.sup.−1, respectively), consistent with an elevated CH4 source from an estuarine outflow driven by local tidal circulation. Based on observations at PPAO, we also estimate the detection limit of the eddy covariance CH.sub.4 flux measurement to be ~20 μmole m.sup.−2 d.sup.−1 over hourly timescales (~4 μmole m.sup.−2 d.sup.−1 over 24 hours).