Export 29 results:
Sort by: Author [ Title  (Asc)] Type Year
A B C D E F G H I J K L M N [O] P Q R S T U V W X Y Z   [Show ALL]
Yu, W, Han W, Maloney ED, Gochis D, Xie S-P.  2011.  Observations of eastward propagation of atmospheric intraseasonal oscillations from the Pacific to the Atlantic. Journal of Geophysical Research-Atmospheres. 116   10.1029/2010jd014336   Abstract
Tanimoto, Y, Xie SP, Kai K, Okajima H, Tokinaga H, Murayama T, Nonaka M, Nakamura H.  2009.  Observations of Marine Atmospheric Boundary Layer Transitions across the Summer Kuroshio Extension. Journal of Climate. 22:1360-1374.   10.1175/2008jcli2420.1   Abstract
Yang, Y, Ma J, Xie SP.  2008.  Observations of the trade wind wakes of Kauai and Oahu. Geophysical Research Letters. 35   10.1029/2007gl031742   Abstract
Wang, Q, Zhang SP, Xie SP, Norris JR, Sun JX, Jiang YX.  2019.  Observed variations of the atmospheric boundary layer and stratocumulus over a warm eddy in the Kuroshio Extension. Monthly Weather Review. 147:1581-1591.   10.1175/mwr-d-18-0381.1   AbstractWebsite

A research vessel sailing across a warm eddy in the Kuroshio Extension on 13 April 2016 captured an abrupt development of stratocumulus under synoptic high pressure. Shipboard observations and results from regional atmospheric model simulations indicate that increased surface heat flux over the ocean eddy lowered surface pressure and thereby accelerated southeasterly winds. The southeasterly winds transported moisture toward the low pressure and enhanced the air-sea interface heat flux, which in turn deepened the low pressure and promoted low-level convergence and rising motion over the warm eddy. The lifting condensation level lowered and the top of the marine atmospheric boundary layer (MABL) rose, thereby aiding the development of the stratocumulus. Further experiments showed that 6 degrees C sea surface temperature anomalies associated with the 400-km-diameter warm eddy accounted for 80% of the total ascending motion and 95% of total cloud water mixing ratio in the marine atmospheric boundary layer during the development of stratocumulus. The synthesis of in situ soundings and modeling contributes to understanding of the mechanism by which the MABL and marine stratocumulus respond to ocean eddies.

Xu, LX, Xie SP, Jing Z, Wu LX, Liu QY, Li PL, Du Y.  2017.  Observing subsurface changes of two anticyclonic eddies passing over the Izu-Ogasawara Ridge. Geophysical Research Letters. 44:1857-1865.   10.1002/2016gl072163   AbstractWebsite

Eddy-bathymetry interactions are common in the ocean, but the full evolution of the interaction is difficult to observe below the surface. Using 17 Iridium Argo floats, we continually track two anticyclonic eddies (AEs) in the North Pacific that migrate westward and encounter the Izu-Ogasawara Ridge. Based on over 5000 Argo profiles following the two AEs, this study presents the first detailed descriptions of changes in eddy vertical structure and diapycnal mixing as the two AEs pass the Ridge. There, we find that isopycnals dome up and the eddy diameter increases, while the diapycnal mixing is enhanced-to the order of 10(-4) m(2) s(-1) or larger, in comparison with an ambient of 10(-5) m(2) s(-1). The enhanced mixing around the AE center in the upper -1000m appears where the underlying bathymetry is shallower than -4000m and is mainly sustained by tidally generated internal waves.

Tokinaga, H, Tanimoto Y, Xie S-P, Sampe T, Tomita H, Ichikawa H.  2009.  Ocean Frontal Effects on the Vertical Development of Clouds over the Western North Pacific: In Situ and Satellite Observations. Journal of Climate. 22:4241-4260.   10.1175/2009jcli2763.1   Abstract
Xu, Y, Xie SP.  2015.  Ocean mediation of tropospheric response to reflecting and absorbing aerosols. Atmospheric Chemistry and Physics. 15:5827-5833.   10.5194/acp-15-5827-2015   AbstractWebsite

Radiative forcing by reflecting (e.g., sulfate, SO4) and absorbing (e.g., black carbon, BC) aerosols is distinct: the former cools the planet by reducing solar radiation at the top of the atmosphere and the surface, without largely affecting the atmospheric column, while the latter heats the atmosphere directly. Despite the fundamental difference in forcing, here we show that the structure of the tropospheric response is remarkably similar between the two types of aerosols, featuring a deep vertical structure of temperature change (of opposite sign) at the Northern Hemisphere (NH) mid-latitudes. The deep temperature structure is anchored by the slow response of the ocean, as a large meridional sea surface temperature (SST) gradient drives an anomalous interhemispheric Hadley circulation in the tropics and induces atmospheric eddy adjustments at the NH mid-latitudes. The tropospheric warming in response to projected future decline in reflecting aerosols poses additional threats to the stability of mountain glaciers in the NH. Additionally, robust tropospheric response is unique to aerosol forcing and absent in the CO2 response, which can be exploited for climate change attribution.

Liu, QY, Xie SP, Li LJ, Maximenko NA.  2005.  Ocean thermal advective effect on the annual range of sea surface temperature. Geophysical Research Letters. 32   10.1029/2005gl024493   Abstract
Tokinaga, H, Xie S-P.  2009.  Ocean tidal cooling effect on summer sea fog over the Okhotsk Sea. Journal of Geophysical Research-Atmospheres. 114   10.1029/2008jd011477   Abstract
Liu, W, Xie SP.  2018.  An ocean view of the global surface warming hiatus. Oceanography. 31:72-79.   10.5670/oceanog.2018.217   AbstractWebsite

The rate of global mean surface temperature increase slowed during 1998-2012. We review oceanic changes during this global warming hiatus from different but related perspectives. In one perspective, we explore the physical mechanisms for sea surface temperature patterns and highlight the role of natural variability, particularly the Interdecadal Pacific Oscillation (IPO) and the Atlantic Multidecadal Oscillation (AMO) that both have chaotic/random phases. In the other perspective, we investigate how the hiatus relates to changes in energy fluxes at the top of the atmosphere and to the three-dimensional distribution of ocean heat content change on decadal timescales. We find that the recent surface warming hiatus is associated with a transition of the IPO from a positive to negative phase and with heat redistribution between the tropical Pacific and Indian Oceans. The AMO has shifted to a positive phase since the late 1990s, inducing a La Nina-type response over the tropical Pacific via a tropic-wide teleconnection, contributing to the global warming hiatus.

Kamae, Y, Mei W, Xie SP.  2019.  Ocean warming pattern effects on future changes in East Asian atmospheric rivers. Environmental Research Letters. 14   10.1088/1748-9326/ab128a   AbstractWebsite

Atmospheric rivers (ARs), intense water vapor transports associated with extra-tropical cyclones, frequently bring heavy rainfalls over mid-latitudes. Over East Asia, landfalling ARs result in major socio-economic impacts including widespread floods and landslides; for example, western Japan heavy rainfall in July 2018 killed more than 200 people. Using results of high-resolution atmospheric model ensemble simulations, we examine projected future change in summertime AR frequency over East Asia. Different sea surface temperature (SST) warming patterns derived from six atmosphere- ocean coupled model simulations were assumed to represent uncertainty in future SST projections. The rate of increase in the frequency of landfalling ARs over summertime East Asia is on average 0.9% K-1 and is dependent on SST warming patterns. Stronger warming over the North Indian Ocean and South China Sea or weaker warming over the tropical central Pacific produce more frequent landfalling ARs over East Asia. These patterns are similar to the co-variability of SST, atmospheric circulation, and ARs over the western North Pacific found on the interannual time scale. The results of this study suggest that the natural disaster risk related to landfalling ARs should increase over East Asia under global warming and SSTs over the Indo-Pacific region holds the key for a quantitative projection.

Vecchi, GA, Xie SP, Fischer AS.  2004.  Ocean-atmosphere covariability in the western Arabian Sea. Journal of Climate. 17:1213-1224. Abstract
Tanimoto, Y, Xie SP.  1999.  Ocean-atmosphere variability over the Pan-Atlantic basin. Journal of the Meteorological Society of Japan. 77:31-46. Abstract
Xie, SP.  1994.  ON PREFERRED ZONAL SCALE OF WAVE-CISK WITH CONDITIONAL HEATING. Journal of the Meteorological Society of Japan. 72:19-30. Abstract
Luebbecke, JF, Boening CW, Keenlyside NS, Xie S-P.  2010.  On the connection between Benguela and equatorial Atlantic Ninos and the role of the South Atlantic Anticyclone. Journal of Geophysical Research-Oceans. 115   10.1029/2009jc005964   Abstract
Xie, SP.  1994.  ON THE GENESIS OF THE EQUATORIAL ANNUAL CYCLE. Journal of Climate. 7:2008-2013. Abstract
Yu, ZJ, Maximenko N, Xie SP, Nonaka M.  2003.  On the termination of the Hawaiian Lee Countercurrent. Geophysical Research Letters. 30   10.1029/2002gl016710   Abstract
Xie, SP, Kubokawa A.  1990.  ON THE WAVE-CISK IN THE PRESENCE OF A FRICTIONAL BOUNDARY-LAYER. Journal of the Meteorological Society of Japan. 68:651-657. Abstract
Kosaka, Y, Xie SP, Lau NC, Vecchi GA.  2013.  Origin of seasonal predictability for summer climate over the Northwestern Pacific. Proceedings of the National Academy of Sciences of the United States of America. 110:7574-7579.   10.1073/pnas.1215582110   AbstractWebsite

Summer climate in the Northwestern Pacific (NWP) displays large year-to-year variability, affecting densely populated Southeast and East Asia by impacting precipitation, temperature, and tropical cyclones. The Pacific-Japan (PJ) teleconnection pattern provides a crucial link of high predictability from the tropics to East Asia. Using coupled climate model experiments, we show that the PJ pattern is the atmospheric manifestation of an air-sea coupled mode spanning the Indo-NWP warm pool. The PJ pattern forces the Indian Ocean (IO) via a westward propagating atmospheric Rossby wave. In response, IO sea surface temperature feeds back and reinforces the PJ pattern via a tropospheric Kelvin wave. Ocean coupling increases both the amplitude and temporal persistence of the PJ pattern. Cross-correlation of ocean-atmospheric anomalies confirms the coupled nature of this PJIO mode. The ocean-atmosphere feedback explains why the last echoes of El Nino-Southern Oscillation are found in the IO-NWP in the form of the PJIO mode. We demonstrate that the PJIO mode is indeed highly predictable; a characteristic that can enable benefits to society.

Li, G, Xie SP.  2012.  Origins of tropical-wide SST biases in CMIP multi-model ensembles. Geophysical Research Letters. 39   10.1029/2012gl053777   AbstractWebsite

Long-standing simulation errors limit the utility of climate models. Overlooked are tropical-wide errors, with sea surface temperature (SST) biasing high or low across all the tropical ocean basins. Our analysis based on Coupled Model Intercomparison Project (CMIP) multi-model ensembles shows that such SST biases can be classified into two types: one with a broad meridional structure and of the same sign across all basins that is highly correlated with the tropical mean; and one with large inter-model variability in the cold tongues of the equatorial Pacific and Atlantic. The first type can be traced back to biases in atmospheric simulations of cloud cover, with cloudy models biasing low in tropical-wide SST. The second type originates from the diversity among models in representing the thermocline depth; models with a deep thermocline feature a warm cold tongue on the equator. Implications for inter-model variability in precipitation climatology and SST threshold for convection are discussed. Citation: Li, G., and S.-P. Xie (2012), Origins of tropical-wide SST biases in CMIP multi-model ensembles, Geophys. Res. Lett., 39, L22703, doi: 10.1029/2012GL053777.