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Feng, M, McPhaden MJ, Xie SP, Hafner J.  2013.  La Nina forces unprecedented Leeuwin Current warming in 2011. Scientific Reports. 3   10.1038/srep01277   AbstractWebsite

Unprecedented warm sea surface temperature (SST) anomalies were observed off the west coast of Australia in February-March 2011. Peak SST during a 2-week period were 5 degrees C warmer than normal, causing widespread coral bleaching and fish kills. Understanding the climatic drivers of this extreme event, which we dub "Ningaloo Nino", is crucial for predicting similar events under the influence of global warming. Here we use observational data and numerical models to demonstrate that the extreme warming was mostly driven by an unseasonable surge of the poleward-flowing Leeuwin Current in austral summer, which transported anomalously warm water southward along the coast. The unusual intensification of the Leeuwin Current was forced remotely by oceanic and atmospheric teleconnections associated with the extraordinary 2010-2011 La Nina. The amplitude of the warming was boosted by both multi-decadal trends in the Pacific toward more La Nina-like conditions and intraseasonal variations in the Indian Ocean.

Feng, M, Hendon HH, Xie SP, Marshall AG, Schiller A, Kosaka Y, Caputi N, Pearce A.  2015.  Decadal increase in Ningaloo Nino since the late 1990s. Geophysical Research Letters. 42:104-112.   10.1002/2014gl062509   AbstractWebsite

Ningaloo Nino refers to the episodic occurrence of anomalously warm ocean conditions along the subtropical coast of Western Australia (WA). Ningaloo Nino typically develops in austral spring, peaks in summer, and decays in autumn, and it often occurs in conjunction with La Nina conditions in the Pacific which promote poleward transport of warm tropical waters by the Leeuwin Current. Since the late 1990s, there has been a marked increase in the occurrence of Ningaloo Nino, which is likely related to the recent swing to the negative phase of the Interdecadal Pacific Oscillation (IPO) and enhanced El Nino-Southern Oscillation variance since 1970s. The swing to the negative IPO sustains positive heat content anomalies and initiates more frequent cyclonic wind anomalies off the WA coast so favoring enhanced poleward heat transport by the Leeuwin Current. The anthropogenically forced global warming has made it easier for natural variability to drive extreme ocean temperatures in the region.

Fu, G, Guo JT, Xie SP, Duane YH, Zhang MG.  2006.  Analysis and high-resolution modeling of a dense sea fog event over the Yellow Sea. Atmospheric Research. 81:293-303.   10.1016/j.atmosres.2006.01.005   Abstract
Fuckar, NS, Xie SP, Farneti R, Maroon EA, Frierson DMW.  2013.  Influence of the extratropical ocean circulation on the intertropical convergence zone in an idealized coupled general circulation model. Journal of Climate. 26:4612-4629.   10.1175/jcli-d-12-00294.1   AbstractWebsite

The authors present coupled model simulations in which the ocean's meridional overturning circulation (MOC) sets the zonal mean location of the intertropical convergence zone (ITCZ) in the hemisphere with deep-water production. They use a coarse-resolution single-basin sector coupled general circulation model (CGCM) with simplified atmospheric physics and two idealized land-sea distributions.In an equatorially symmetric closed-basin setting, unforced climate asymmetry develops because of the advective circulation-salinity feedback that amplifies the asymmetry of the deep-MOC cell and the upper-ocean meridional salinity transport. It confines the deep-water production and the dominant extratropical ocean heat release to a randomly selected hemisphere. The resultant ocean heat transport (OHT) toward the hemisphere with the deep-water source is partially compensated by the atmospheric heat transport (AHT) across the equator via an asymmetric Hadley circulation, setting the ITCZ in the hemisphere warmed by the ocean.When a circumpolar channel is open at subpolar latitudes, the circumpolar current disrupts the poleward transport of the upper-ocean saline water and suppresses deep-water formation poleward of the channel. The MOC adjusts by lowering the main pycnocline and shifting the deep-water production into the opposite hemisphere from the channel, and the ITCZ location follows the deep-water source again because of the Hadley circulation adjustment to cross-equatorial OHT. The climate response is sensitive to the sill depth of the channel but becomes saturated when the sill is deeper than the main pycnocline depth in subtropics. In simulations with a circumpolar channel, the ITCZ is in the Northern Hemisphere (NH) because of the Southern Hemisphere (SH) circumpolar flow that forces northward OHT.

Fujiwara, M, Xie SP, Shiotani M, Hashizume H, Hasebe F, Vomel H, Oltmans SJ, Watanabe T.  2003.  Upper-tropospheric inversion and easterly jet in the tropics. Journal of Geophysical Research-Atmospheres. 108   10.1029/2003jd003928   Abstract
Fyfe, JC, Meehl GA, England MH, Mann ME, Santer BD, Flato GM, Hawkins E, Gillett NP, Xie S-P, Kosaka Y, Swart NC.  2016.  Making sense of the early-2000s warming slowdown. Nature Clim. Change. 6:224-228.: Nature Publishing Group   10.1038/nclimate2938   Abstract

It has been claimed that the early-2000s global warming slowdown or hiatus, characterized by a reduced rate of global surface warming, has been overstated, lacks sound scientific basis, or is unsupported by observations. The evidence presented here contradicts these claims.