East Asia is a region with complex topography, land surface conditions, coastlines, and large contribution from mesoscale phenomena, such as the mei-yu/baiu frontal systems tropical storms. To study regional climate in region, highly resolved model (IPRC-RegCM) has been recently developed at International Pacific Research Center (IPRC). The distinct features of this include direct feedback cumulus detrained cloud ice water into grid-resolved quantities; effect buoyancy on turbulence...

Dongjiang River Network (DJRN), a complex urbanized river network in the Pearl Basin, China. Low-oxygen conditions have been expanding systems, whereas clear and quantitative understanding on deoxygenation processes is still lacking. This study utilized well-validated physical-biogeochemical model to investigate oxygen dynamics combined with ecosystem metabolisms over an annual cycle explicitly quantify contribution of major oxygen-depleting substances from different sources low-oxygen...

Abstract. Biogeochemical ocean models are useful tools but subject to uncertainties arising from simplifications, inaccurate parameterization of processes, and poorly known model parameters. Parameter optimization is a standard method for addressing the latter typically cannot constrain all biogeochemical parameters because insufficient observations. Here we assess trade-offs between satellite observations color (BGC) Argo profiles benefits combining both observation types optimizing in Gulf...

Abstract Model parameterizations of particulate organic carbon (POC) flux are critical for simulating the strength and future evolution biological pump (BCP) but remain poorly constrained because direct observations sparse. Here, we ask whether Biogeochemical (BGC)‐Argo proxy POC can help distinguish between these by objectively comparing two common parameterizations, which reproduce observed slowdown attenuation with depth either decreasing remineralization rate or increasing sinking...

Abstract. A three-dimensional (3-D) physical–biogeochemical coupled model was applied to explore the mechanisms controlling dissolved oxygen (DO) dynamics and bottom hypoxia during summer in Pearl River estuary (PRE). By using numerical tracers, we proposed a new method (namely physical modulation method) quantify contributions of boundary conditions each source sink process occurring local adjacent waters DO conditions. mass balance analysis based on indicated that at layer were mainly...

Abstract. Increase in riverine nutrient loads was generally recognized as the primary cause of coastal deoxygenation, whereas role other factors, especially suspended sediments, has received less attention. This study aims to discern impacts anthropogenic alterations various inputs on subsurface deoxygenation over past three decades a large river-dominated estuary, Pearl River Estuary (PRE). By utilizing physical-biogeochemical model, we reproduced observed dissolved oxygen (DO) conditions...

Abstract Ocean alkalinity enhancement (OAE) can potentially remove gigatons of CO 2 from the atmosphere for durable storage in ocean. Before implementing OAE at climate‐relevant scales, questions about its safety and verifiability must be addressed. Operational deployment poses a dilemma between pursuing large detectability, essential effective monitoring, reporting, verification, ensuring environmental satisfying regulatory requirements. In this study, we present computationally efficient...

Accurately and timely estimating three-dimensional ocean states is crucial for improving operational forecasting capabilities. Although satellite observations provide valuable evolutionary information, they are confined to surface-level variables. While in situ can offer subsurface their spatiotemporal distribution highly uneven, making it difficult obtain complete structures. This study developed an operational-oriented lightweight framework state reconstruction by integrating multi-source...

Abstract. The Pearl River estuary (PRE) frequently experiences low-oxygen conditions in summer, with large-extent events and a long-term deoxygenation trend being reported recently. In this study, we provide synthesis of the spatiotemporal patterns incidence different levels PRE based on situ observations collected from 1976 to 2017 aim elucidate underlying mechanisms their changes over past 4 decades. show that dissolved oxygen (DO) content has had significant temporal variability spatial...

Abstract. In summer, the Pearl River estuary (PRE) experiences hypoxia, largely driven by high input of fresh water with low dissolved oxygen (DO), abundant nutrients and particulate organic carbon from network. this study, we used a well-validated physical–biogeochemical model together DO species-tracing method to study responses hypoxia dynamics anthropogenic perturbations riverine inputs (i.e. DO, nutrients, carbon) in July–August 2006. Model results showed that PRE was most sensitive...

Abstract The biological carbon pump exerts a strong control on atmospheric CO 2 levels. It includes range of processes that generate organic in the surface ocean and transport this matter from to deep where it is remineralized sequestered as inorganic for decades millennia. While productivity relatively well observed through combination approaches including remote sensing, magnitude vertical remains poorly constrained by observations detailed involved are insufficiently understood. In...

Abstract Coronavirus disease 2019 (COVID-19) pandemic has led to a rare reduction in human activities. In such background, data from ground-based environmental stations, satellites, and reanalysis materials are utilized conduct comprehensive analysis of the global air quality changes during COVID-19 outbreak. The results showed that under impact outbreak, significant decrease particulate matter (PM x ) nitrogen dioxide (NO 2 occurred more than 40% world’s land area, with NO decreasing by...

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2014Final laser-beam Q-migrationAuthors: Xiang Xiao*Feng HaoChristopher EggerBin WangFangxiang JiaoXinling WangXiang Xiao*TGS, Feng HaoTGS, Christopher EggerTGS, Bin WangTGS, Fangxiang JiaoTGS, and Xinling WangTGShttps://doi.org/10.1190/segam2014-1432.1 SectionsSupplemental MaterialAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract We present a common...

Abstract. Assessments of ocean data assimilation (DA) systems and observing system design experiments typically rely on identical or nonidentical twin experiments. The approach has been recognized as yielding biased impact assessments in atmospheric predictions, but these shortcomings are not sufficiently appreciated for oceanic DA applications. Here we present the first direct comparison approaches an application. We assess both a Gulf Mexico that uses ensemble Kalman filter. Our...

Abstract. The Pearl River estuary (PRE) frequently experiences low-oxygen conditions in summer, with large extents of events and a long-term deoxygenation trend being reported recently. In this study, we provide synthesis the spatiotemporal patterns incidence different levels PRE based on in-situ observations collected from 1976 to 2017, aim elucidate underlying mechanisms their changes over past 4 decades. show that oxygen content had significant temporal variability spatial heterogeneity....

Abstract Model uncertainty in simulating the biological carbon pump was quantified and partitioned using 14 models from Coupled Intercomparison Project Phase 6. Uncertainty increases with depth. On global scale, export dominates above 900 m transfer efficiency below. Reducing model offers similar benefits for understanding century-scale sequestration climate. These produce three different qualitative patterns efficiency: one where it is globally homogenous two opposite latitudinal due to...

Abstract. The summertime low-oxygen conditions in the Pearl River Estuary (PRE) have experienced a significant spatial expansion associated with notable deoxygenation recent decades. Nevertheless, there is still lack of quantitative data on long-term trends and interannual variabilities oxygen PRE as well driving factors. Therefore, subregion (the coastal waters off Hong Kong) was comprehensively investigated this study using monthly observations during 1994–2018. To evaluate changes scope...