Abstract. We developed a carbon data assimilation system to estimate surface fluxes using the local ensemble transform Kalman filter (LETKF) and atmospheric transport model GEOS-Chem driven by MERRA-1 reanalysis of meteorological field based on Goddard Earth Observing System model, version 5 (GEOS-5). This is inspired method Kang et al. (2011, 2012), who estimated in an observing simulation experiment (OSSE) as evolving parameters CO2, short window 6 h. They included standard variables, so...

Estimates of atmospheric CO2 uptake by the Arctic Ocean over recent decades from multiple methods indicate accelerating regional carbon (Yasunaka et  al. 2024). This trend is  attributed to such factors as climate-change impacts and associated sea-ice loss. Yasunaka et (2024) also note a significant range uncertainty among various model data analysis that were employed derive air-sea fluxes (e.g., surface ocean pCO2 products, biogeochemical models, inversions). highlights...

Atmospheric inverse analyses use optimization methods to calculate surface CO2 fluxes using atmospheric transport models in combination with observed gradients concentration. In our present study we an estimate of Arctic Ocean air-sea the GEOSChem–LETKF  system; this system has previously been used derive estimates regional North Atlantic (Chen et al. 2021). Our analysis reports on  and assesses patterns spatial and inter-annual variability.  Our results...

Abstract. Non-methane hydrocarbons (NMHCs) in the marine atmosphere have been extensively studied due to their important roles regulating atmospheric chemistry and climate. However, very little is known about distribution sources of NMHCs lower over marginal seas China. Herein, we characterized (C2-C5) both coastal cities China spring 2021, with a focus on identifying atmosphere. The urban atmospheres, especially for alkanes, were significantly higher compared that atmosphere, suggesting...

Abstract. Non-methane hydrocarbons (NMHCs) in the marine atmosphere have been studied extensively due to their important roles regulating atmospheric chemistry and climate. However, very little is known about distribution sources of NMHCs lower over marginal seas China. Herein, we characterized (C2–C5) both coastal cities China spring 2021, with a focus on identifying atmosphere. The urban atmospheres, especially alkanes, were significantly higher compared those atmosphere, suggesting that...

Abstract The Southern Ocean is an important sink of anthropogenic CO 2 , but it among the least well-observed ocean basins, and consequentially substantial uncertainties in flux reconstruction exist. A recent attempt to address historically sparse wintertime sampling produced ‘pseudo’ observations surface pCO using subsurface summertime south Antarctic Polar Front. Here, we present estimate that combines a machine learning-based mapping method with updated set pseudo increases regional data...

 The Arctic Ocean is responsible for around 5-10% of oceanic CO2 uptake, despite the region only accounting approximately 4% world's oceans (Bates & Mathis, 2009). In this study, we investigate exchange between atmosphere and ocean in period 2000-2017. Our estimates are obtained using GEOSChem-LETKF inverse model system (Chen et al. 2021), combination with data from NOAA surface monitoring network (ObsPack, Cooperative Global Atmospheric Data Integration Project, 2018). We...

Estimates of global scale air-sea CO2 fluxes have traditionally been derived from ocean biogeochemistry models and surface pCO2 data products (Friedlingstein et al. 2022). An alternative means estimating carbon uptake is provided by atmospheric inversions; these use optimization procedures assimilation methods to combine measurements with numerical transport model simulations prior knowledge fluxes.  Here we the GEOSChem-LETKF (GCLETKF) inverse system (Chen 2021) in conjunction...

Extreme atmospheric rivers (EARs) are responsible for most of the severe precipitation and disastrous flooding along coastal regions in midlatitudes. However, current non-eddy-resolving climate models severely underestimate (~50%) EARs, casting significant uncertainties on their future projections. Here, using an unprecedented set eddy-resolving high-resolution simulations from Community Earth System Model simulations, we show that models’ ability simulating EARs is significantly...

Abstract. We developed a Carbon data assimilation system to estimate the surface carbon fluxes using Local Ensemble Transform Kalman Filter and atmospheric transfer model of GEOS-Chem driven by MERRA-1 reanalysis meteorological fields based on Goddard Earth Observing System Model, Version 5 (GEOS-5). This is inspired method Kang et al. [2011, 2012], who estimated in an Simulation Experiment (OSSE) mode, as evolving parameters CO2, short window 6 hours. They included standard variables, so...

Surface soil samples collected at 18 sites from the northeast Tibetan Plateau were used to analyze perfluoroalkyl substances (PFASs) via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) study concentration levels and sources of PFASs. The results showed that 11 PFASs detected in soil, ω(Σ11PFASs) ranged 0.043-1.573 ng·g-1 with an average 0.398 ng·g-1. PFBA displayed highest level a mean content 0.164 ng·g-1, whereas PFHxA was lowest (0.005 ng·g-1). concentrations...

Abstract. We present new estimates of the regional North Atlantic (15–80∘ N) CO2 flux for 2000–2017 period using atmospheric measurements from NOAA long-term surface site network in combination with an carbon cycle data assimilation system (GEOS-Chem–LETKF, Local Ensemble Transform Kalman Filter). assess sensitivity to alternative ocean prior distributions and specification uncertainties associated fluxes. a scheme characterize uncertainty fluxes, derived set eight pCO2-based products, which...

Abstract. We developed a Carbon data assimilation system to estimate the surface carbon fluxes using Local Ensemble Transform Kalman Filter and atmospheric transfer model of GEOS-Chem driven by MERRA-1 reanalysis meteorological fields based on Goddard Earth Observing System Model, Version 5 (GEOS-5). This is inspired method Kang et al. (2011, 2012), who estimated in an Simulation Experiment (OSSE) mode, as evolving parameters CO2, short window 6 hours. They included standard variables, so...

Oceanic uptake of atmospheric CO2 has been estimated to remove ~25%  global anthropogenic emissions in recent decades (1990-2020), and this flux displays significant decadal variability (Global Carbon Budget: Friedlingstein et al. 2022). Key contributors ocean estimate are data products derived from interpolated surface pCO2 measurements combined with air-sea gas-exchange parameterizations.  Although a common database (Surface Ocean Atlas (SOCAT), Bakker 2016), these...

For China, the implementation of marine liability insurance is not only an obligation determined by China's international treaty obligations, but also objective requirement for development shipping, resources and other industries.In some areas, environmental has been 'enforced to implement' through legislation guided promoted policies.Insurance companies are great players in market.In order implement better, it necessary further improve legal system; establish policy institutions, reasonably...

Abstract. We present new estimates of the regional North Atlantic (15° N–80° N) CO2 flux for 2000–2017 period using atmospheric measurements from NOAA long term surface site network in combination with an data assimilation system (GEOSChem–LETKF). also assess sensitivity to representation prior ocean distribution and associated specification uncertainty, including a that is dependent on agreement among multiple representations flux. Long average are −0.26±0.04 PgC y−1 subtropical basin N–50°...