Xu, X., Chassignet, E. P., Johns, W. E., Schmitz Jr, W. J., & Metzger, E. J. (2014). Intraseasonal to interannual variability of the Atlantic meridional overturning circulation from eddy-resolving simulations and observations. J. Geophys. Res. Oceans , 119 (8), 5140–5159.
Xu, X., Chassignet, E. P., Price, J. F., Özgökmen, T. M., & Peters, H. (2007). A regional modeling study of the entraining Mediterranean outflow. J. Geophys. Res. , 112 (C12).
Xu, X., Rhines, P. B., & Chassignet, E. P. (2018). On Mapping the Diapycnal Water Mass Transformation of the Upper North Atlantic Ocean. J. Phys. Oceanogr. , 48 (10), 2233–2258.
Abstract: Diapycnal water mass transformation is the essence behind the Atlantic meridional overturning circulation (AMOC) and the associated heat/freshwater transports. Existing studies have mostly focused on the transformation that is forced by surface buoyancy fluxes, and the role of interior mixing is much less known. This study maps the three-dimensional structure of the diapycnal transformation, both surface forced and mixing induced, using results of a high-resolution numerical model that have been shown to represent the large-scale structure of the AMOC and the North Atlantic subpolar/subtropical gyres well. The analyses show that 1) annual mean transformation takes place seamlessly from the subtropical to the subpolar North Atlantic following the surface buoyancy loss along the northward-flowing upper AMOC limb; 2) mixing, including wintertime convection and warm-season restratification by mesoscale eddies in the mixed layer and submixed layer diapycnal mixing, drives transformations of (i) Subtropical Mode Water in the southern part of the subtropical gyre and (ii) Labrador Sea Water in the Labrador Sea and on its southward path in the western Newfoundland Basin; and 3) patterns of diapycnal transformations toward lighter and denser water do not align zonally�the net three-dimensional transformation is significantly stronger than the zonally integrated, two-dimensional AMOC streamfunction (50% in the southern subtropical North Atlantic and 60% in the western subpolar North Atlantic).
Xu, X., Rhines, P. B., & Chassignet, E. P. (2016). Temperature-Salinity Structure of the North Atlantic Circulation and Associated Heat and Freshwater Transports. J. Climate , 29 (21), 7723–7742.
Xu, X., Rhines, P. B., Chassignet, E. P., & Schmitz Jr., W. J. (2015). Spreading of Denmark Strait Overflow Water in the Western Subpolar North Atlantic: Insights from Eddy-Resolving Simulations with a Passive Tracer. J. Phys. Oceanogr. , 45 (12), 2913–2932.
Xu, X., Schmitz Jr., W. J., Hurlburt, H. E., Hogan, P. J., & Chassignet, E. P. (2010). Transport of Nordic Seas overflow water into and within the Irminger Sea: An eddy-resolving simulation and observations. J. Geophys. Res. , 115 (C12).
Xue, W., Xin, X., Zhang, J., Zhang, W., Wu, H., Huang, Z., et al. (2016). Development and Testing of a Multi-model Ensemble Coupling Framework. In Development and Evaluation of High Resolution Climate System Models (pp. 163–208). Springer.
Yan, Y., Chassignet, E. P., Qi, Y., & Dewar, W. K. (2013). Freshening of Subsurface Waters in the Northwest Pacific Subtropical Gyre: Observations and Dynamics. J. Phys. Oceanogr. , 43 (12), 2733–2751.
Yan, Y., Liu, Y., & Lu, J. (2016). Cloud vertical structure, precipitation, and cloud radiative effects over Tibetan Plateau and its neighboring regions. J. Geophys. Res. Atmos. , 121 (10), 5864–5877.
Yarboro, J. (2017). Wildfire Modeling: Developing a computer simulation of a burning front using the reaction-diffusion equation . Bachelor's thesis, Florida State University, Tallahassee, FL.