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Recent CO 2 gradients over Europe M.Ramonet, P.Ciais et al. Marine & Continental sites over Europe. The CO 2 time series over Europe. PUY (all data) ORL (2000-3000m) SCH (selected data) HH1 (selected data) PAL (selected data) BAL (ESRL/NOAA flask) BSC (ESRL/NOAA flask). PUY (all data)
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Recent CO2 gradients over Europe M.Ramonet, P.Ciais et al.
The CO2 time series over Europe PUY (all data) ORL (2000-3000m) SCH (selected data) HH1 (selected data) PAL (selected data) BAL (ESRL/NOAA flask) BSC (ESRL/NOAA flask) PUY (all data) ORL (2000-3000m) SCH (all data) HH1 (all data) PAL (all data) BAL (ESRL/NOAA flask) BSC (ESRL/NOAA flask) Monthly means or individual flask data
What are the main drivers for trend and interannual variability of CO2 gradients over Europe ?
Winter NAO Winter (Dec-Mar) Station Based NAO Index http://www.cgd.ucar.edu/cas/jhurrell/indices.data.html#naostatmon
PBL height from radiosoundings • Mean SUMMER inland trend: 200m/10years: 2%/year • Mean YEAR inland: 100m/10years: 1%/year Vautard et al.
PBL height from ECMWF • Comparison ECMWF vs radiosoundings ? • Strong interest for collocated observations of PBL height and CO2
Fossil fuel emissions from CDIAC Eastern = Germany, Poland, Switzerland, Austria, Eastern europe Western = France, UK, Ireland, Benelux Mediterranean = Portugal, Spain, Italy, Greece Northern = Denmark, Sweden, Norway, Finland, + 3 baltic states Paris et al.
SOURCE SINK Sea surface CO2 in N.Atlantic fCO2 (µatm) calculated with DIC and TA (53°N - 62°N) Atmosphere (MHD) The ocean fCO2 evolution is mainly related to sea surface warming, up to 2°C since 1993 and results in a large changes for the air-sea CO2 fluxes Corbières et al., 2007 8
BSC BAL Influence of the flask sampling time BSC: Local Time - 2 hour(s) = UTC BAL: Local Time - 1 hour(s) = UTC
Influence of the flask sampling time All flasks Selected flasks
Seasonal trends compared to Mace Head PUY (all data) ORL (2000-3000m) SCH (selected data) HH1 (selected data) PAL (selected data) BAL (ESRL/NOAA flask) BSC (ESRL/NOAA flask)
Comparison of CO2 & CO trends CO2 CO NOAA flasks
EU carbon fluxes [1995-2000] vs [2001-2005] CO2 gradient increased by ~35% ~ +0.3 PgC y-1 Fossil fuel increased by ~3% ~ +0.03 PgC y-1 2003 anomaly Ecosystems = +0.5 PgC y-1 [Ciais et al., 2005] Fossil fuel = +0.9 ± 0.02 PgC y-1 [UNFCC: 1990-2003] Ecosystems = -0.11 ± 0.28 PgC y-1 [Janssens et al., 2003] => European carbon balance +0.8 ± 0.3 PgC y-1
CO2 gradients between many continental sites (PUY, ORL, HH1, BAL, BSC) and marine sites over Europe are higher (~35%) in 2001‑2005 compared to 1993‑2000. • Not highly sensitive to the data selection schemes. • Some sites (PUY, BAL) show a higher signal in Spring. • Fossil fuel emissions are increasing (+3%), but do not seem to explain the observed signal (factor of 10). CO gradients are not increasing (BAL, BSC, HUN). • Results consistent with Ciais et al.(2005) => 3-5 years anomaly ? • To be investigated: • Changes in the atmospheric transport • Changes in the spatial distribution of anthropogenic sources • Other dataset (eddy flux time series, satellite data, ...)