@article{yang_guo_zeng_wang_2023, title={Eddy-induced sea surface salinity changes in the South China Sea}, volume={10}, url={http://dx.doi.org/10.3389/fmars.2023.1113752}, DOI={10.3389/fmars.2023.1113752}, abstractNote={Eddy-induced sea surface salinity (SSS) changes are systematically studied in the South China Sea (SCS) by using Soil Moisture Active Passive (SMAP) satellite salinity data from 2015 to 2021 for the first time. All eddies in the SCS during this period are analysed, and two normalized eddy composites are reconstructed under the long-term basin mean. In general, anticyclonic eddies (AEs) tend to result in lower salinity than cyclonic eddies (CEs) in the upper ocean. The salinity anomalies of the AE and CE composites are dominated by dipole and monopole structures, respectively. The different patterns in eddy-induced salinity anomalies are generally controlled by horizontal and vertical advections, which is further confirmed by their seasonal evolutions. A spatiotemporal decomposition of these salinity anomaly patterns suggests that the dipole and monopole patterns account for more than 70% of the salinity variability. All the eddies in the SCS are monopole-dominated and dipole-supplemented overall. This finding infers a relatively uniform eddy-induced salinity structure across the SCS and provides an observational-based metric for future model studies.}, journal={Frontiers in Marine Science}, publisher={Frontiers Media SA}, author={Yang, Yikai and Guo, Yiming and Zeng, Lili and Wang, Qiang}, year={2023}, month={Mar} }
 @article{guo_bishop_bryan_bachman_2023, title={Mesoscale Variability Linked to Interannual Displacement of Gulf Stream}, volume={50}, ISSN={["1944-8007"]}, url={https://doi.org/10.1029/2022GL102549}, DOI={10.1029/2022GL102549}, abstractNote={AbstractThe impacts of interannual oscillations of the Gulf Stream (GS) on oceanic mesoscale variability are investigated using satellite observations of sea surface height (SSH) and sea surface temperature (SST) from 1993 to 2018. We show that variations in GS position, strength, and meandering status are the dominant spatiotemporal modes in regional SSH variability as they explain over 50% of the total variance. In particular, meridional shift of the GS associated with the large‐scale wind variation over the North Atlantic contributes to approximately 30% of SSH variability. We further find that this path displacement mode can drive approximately 15% of regional mesoscale variability in eddy kinetic energy and divergent eddy heat flux. This observational‐based evidence of ocean mesoscale response to GS shift infers a potentially important forcing mechanism that could drive eddy‐scale ocean variability and has far‐reaching implications for regional ocean and ecosystem dynamics in response to climate variation.}, number={7}, journal={GEOPHYSICAL RESEARCH LETTERS}, author={Guo, Yiming and Bishop, Stuart and Bryan, Frank and Bachman, Scott}, year={2023}, month={Apr} }
 @article{guo_bishop_bryan_bachman_2022, title={A Global Diagnosis of Eddy Potential Energy Budget in an Eddy-Permitting Ocean Model}, volume={52}, ISSN={["1520-0485"]}, url={http://dx.doi.org/10.1175/jpo-d-22-0029.1}, DOI={10.1175/JPO-D-22-0029.1}, abstractNote={Abstract
We use an interannually forced version of the Parallel Ocean Program, configured to resolve mesoscale eddies, to close the global eddy potential energy (EPE) budget associated with temperature variability. By closing the EPE budget, we are able to properly investigate the role of diabatic processes in modulating mesoscale energetics in the context of other processes driving eddy–mean flow interactions. A Helmholtz decomposition of the eddy heat flux field into divergent and rotational components is applied to estimate the baroclinic conversion from mean to eddy potential energy. In doing so, an approximate two-way balance between the “divergent” baroclinic conversion and upgradient vertical eddy heat fluxes in the ocean interior is revealed, in accordance with baroclinic instability and the relaxation of isopycnal slopes. However, in the mixed layer, the EPE budget is greatly modulated by diabatic mixing, with air–sea interactions and interior diffusion playing comparable roles. Globally, this accounts for ∼60% of EPE converted to EKE (eddy kinetic energy), with the remainder being dissipated by air–sea interactions and interior mixing. A seasonal composite of baroclinic energy conversions shows that the strongest EPE to EKE conversion occurs during the summer in both hemispheres. The seasonally varying diabatic processes in the upper ocean are further shown to be closely linked to this EPE–EKE conversion seasonality, but with a lead. The peak energy dissipation through vertical mixing occurs ahead of the minimum EKE generation by 1–2 months.}, number={8}, journal={JOURNAL OF PHYSICAL OCEANOGRAPHY}, publisher={American Meteorological Society}, author={Guo, Yiming and Bishop, Stuart and Bryan, Frank and Bachman, Scott}, year={2022}, month={Aug}, pages={1731–1748} }
 @article{guo_bachman_bryan_bishop_2022, title={Increasing Trends in Oceanic Surface Poleward Eddy Heat Flux Observed Over the Past Three Decades}, volume={49}, ISSN={["1944-8007"]}, url={https://doi.org/10.1029/2022GL099362}, DOI={10.1029/2022GL099362}, abstractNote={AbstractMesoscale processes make the largest contribution to ocean variability and are significant agents in ocean heat transport. In this investigation, we provide evidence based on satellite observations for an increasing trend in surface transient eddy heat flux (EHF) over the period 1993–2020. The enhanced EHF is particularly prominent in western boundary currents and their extensions at mid‐latitudes, with increases of 20%–40% per decade. Additionally, we decompose the EHF trend into contributions from velocity variance, temperature variance and a coherence parameter using a Cauchy–Schwarz inequality. We find that each contributes to the spatial pattern of the trend in EHF, with the contribution from enhanced temperature variance dominating the global zonal mean EHF trend over the past few decades.}, number={16}, journal={GEOPHYSICAL RESEARCH LETTERS}, publisher={American Geophysical Union (AGU)}, author={Guo, Yiming and Bachman, Scott and Bryan, Frank and Bishop, Stuart}, year={2022}, month={Aug} }
 @inproceedings{mesoscale air-sea interaction and the ocean eddy potential energy budget, is it important?_2022, booktitle={Ocean Sciences Meeting 2022}, year={2022}, month={Mar} }
 @phdthesis{guo_2022, title={On the Ocean Divergent Eddy Heat Flux and its Variability in the Western Boundary Currents}, author={Guo, Yiming}, year={2022} }
 @article{guo_bishop_2022, title={Surface Divergent Eddy Heat Fluxes and Their Impacts on Mixed Layer Eddy-Mean Flow Interactions}, volume={14}, ISSN={["1942-2466"]}, url={https://doi.org/10.1029/2021MS002863}, DOI={10.1029/2021MS002863}, abstractNote={AbstractIn this study, the global surface divergent eddy heat flux (EHF) is estimated using remote sensing observations of sea surface height (SSH) and sea surface temperature (SST) over two decades (1993–2017). These results are used as a metric to assess model fidelity in a mesoscale eddy‐resolving version of the Community Earth System Model. The estimated EHFs show that the midlatitudes significantly contribute to the poleward transport of heat because of strong regional variability in SSH and SST. A Helmholtz decomposition is performed on the global EHFs to remove prominent nondynamic rotational wave‐like structures that appear in these fluxes. The dynamic divergent EHFs are responsible for driving cross‐frontal exchange and positive Baroclinic Conversion (BC) rates, suggesting a conversion of mean potential energy to eddy potential energy within the mixed layer. The results show that the model captures the same spatial patterns of EHFs and BC rates, but with relatively higher values in the midlatitudes than observations. The mixed layer geostrophic meridional eddy heat transport reaches maximums of 0.07 PW and 0.1 PW in the midlatitudes in the observations and climate model, respectively. The global integrated BC rate is 0.11 TW in the observations, which is ∼30% weaker than the climate model (0.16 TW). A cross‐spectral analysis further shows that the model has higher energy in low‐frequency bands for periods greater than 10 months in the northern hemisphere western boundary currents, but can capture the major spectral peaks in EHFs that are seen in observations.}, number={4}, journal={JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS}, publisher={American Geophysical Union (AGU)}, author={Guo, Yiming and Bishop, Stuart P.}, year={2022}, month={Apr} }
 @inproceedings{interannual variability of observed surface divergent meridional eddy heat fluxes in the kuroshio extension and gulf stream_2020, url={https://agu.confex.com/agu/osm20/preliminaryview.cgi/Paper655339.html}, booktitle={Ocean Sciences Meeting 2020}, year={2020}, month={Feb} }
 @article{bishop_guo_bryan_small_2020, title={The global sink of available potential energy by mesoscale air-sea interaction}, volume={18}, url={https://doi.org/10.5065/g8w0-fy32}, DOI={10.5065/g8w0-fy32}, journal={US CLIVAR Variations}, author={Bishop, S. and Guo, Y. and Bryan, F. and Small, J.}, year={2020}, pages={13–16} }