Abstract:Eddy kinetic energy (EKE) is one key dynamic parameter to characterize atmospheric circulations and synoptic-scale disturbance activities. Investigation of the distribution and variability of atmospheric EKE and related energy conversion components over the South China Sea (SCS) can help us to better understand the dynamics of the SCS monsoon and tropical cyclone (TC) formation in this region. We present our investigation on the interannual variations of low-level (850-hPa) atmospheric EKE over the SCS in this study. Both northern and southern SCS experienced prominent interannual variation in the 850-hPa EKE during their most active EKE months. The energy processes for generation and maintenance of the EKE were analyzed based on the EKE tendency equation. Results suggested that the barotropic energy conversion (BEC) term made the largest contribution to the interannual variation of the EKE over both northern and southern SCS. The interannual variation of the BEC over the southern SCS was mainly modulated by the El Ni?o-Southern Oscillation (ENSO) and had a close anti-correlated relationship with the sea surface temperature (SST) in the eastern equatorial Pacific. In contrast, the interannual variation of the BEC over the northern SCS was identified to be closely associated with the zonal SST gradient between the central equatorial Pacific and northern Indian Ocean. The atmospheric circulation anomalies in responses to SST anomalies enhanced the zonal wind shear over the SCS, giving rise to more BEC. The interannual variation of the BEC over the southern SCS was positively correlated with the TC formation number, with more (less) TCs formed during enhanced (suppressed) BEC years. However, the correlation between the BEC and TC formation number over the northern SCS was not significant, which may be due to the offsetting effects on TC formation by the cooling (warming) of the local SST during enhanced (suppressed) BEC years. These results could improve our understanding of the behaviors and causes of interannual variation in the low-level atmospheric EKE and its relationship with interannual variation of the TC formation number over the SCS. The results highlighted the differences in the regional climate variability between the northern SCS and the southern SCS. ?????

Alert Name:
Alerting to:
Authentication email will be sent to your email address in 24 hours
Frequency:
Email Message Format:	Plain text Graphical(HTML)

Complete the form below and we will recommend the selected titles to your friends on your behalf. * Indicates a required field.
Your name*:
Your email address*:
Recipient's name*:
Recipient's email address*:
(multiple recipient's names and email addresses should be separated with semicolons)
Your comments:	I thought you would find the page(s) useful.

Your name:
Your email address:
Recipient's name:
Recipient's email address:
(multiple recipient's names and email addresses should be separated with semicolons)
Your comments:	I thought you would find this page useful.

Disclaimer: This message was sent to your friend using the "Send it to a friend" facility on the Sciencepaper Online’ WWW site, http://www.paper.edu.cn/en. The Sciencepaper Online is not responsible for the content of this email, and anything said in this email does not necessarily reflect the Sciencepaper Online's views.


	1. Interannual variation of the low-level atmospheric eddy kinetic energy over the South China Sea and its relationship with the tropical cyclone formation number
	WANG Lei
	Earth Science 10 February 2018
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:Eddy kinetic energy (EKE) is one key dynamic parameter to characterize atmospheric circulations and synoptic-scale disturbance activities. Investigation of the distribution and variability of atmospheric EKE and related energy conversion components over the South China Sea (SCS) can help us to better understand the dynamics of the SCS monsoon and tropical cyclone (TC) formation in this region. We present our investigation on the interannual variations of low-level (850-hPa) atmospheric EKE over the SCS in this study. Both northern and southern SCS experienced prominent interannual variation in the 850-hPa EKE during their most active EKE months. The energy processes for generation and maintenance of the EKE were analyzed based on the EKE tendency equation. Results suggested that the barotropic energy conversion (BEC) term made the largest contribution to the interannual variation of the EKE over both northern and southern SCS. The interannual variation of the BEC over the southern SCS was mainly modulated by the El Ni?o-Southern Oscillation (ENSO) and had a close anti-correlated relationship with the sea surface temperature (SST) in the eastern equatorial Pacific. In contrast, the interannual variation of the BEC over the northern SCS was identified to be closely associated with the zonal SST gradient between the central equatorial Pacific and northern Indian Ocean. The atmospheric circulation anomalies in responses to SST anomalies enhanced the zonal wind shear over the SCS, giving rise to more BEC. The interannual variation of the BEC over the southern SCS was positively correlated with the TC formation number, with more (less) TCs formed during enhanced (suppressed) BEC years. However, the correlation between the BEC and TC formation number over the northern SCS was not significant, which may be due to the offsetting effects on TC formation by the cooling (warming) of the local SST during enhanced (suppressed) BEC years. These results could improve our understanding of the behaviors and causes of interannual variation in the low-level atmospheric EKE and its relationship with interannual variation of the TC formation number over the SCS. The results highlighted the differences in the regional climate variability between the northern SCS and the southern SCS. ?????
	TO cite this article:WANG Lei. Interannual variation of the low-level atmospheric eddy kinetic energy over the South China Sea and its relationship with the tropical cyclone formation number[OL].[10 February 2018] http://en.paper.edu.cn/en_releasepaper/content/4743499


	2. Seasonal variation of the low-level atmospheric eddy kinetic energy over the South China Sea and its influences on the tropical cyclone genesis
	WANG Lei
	Earth Science 29 June 2017
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In this paper, the seasonal variation of the low-level atmospheric eddy kinetic energy (EKE) over the South China Sea (SCS) and its influences on the tropical cyclone (TC) genesis over this region were investigated. Different seasonal cycles of the low-level atmospheric EKE were identified between the northern and southern SCS. Although the minimum EKE occurred in the transition season of spring (March-May) in both northern and southern SCS, July-September were the most active EKE months over the northern SCS, while October-December were for the southern SCS. The energy processes for generation and maintenance of the low-level atmospheric EKE were analyzed based on the EKE tendency equation. Results suggested that eddy geopotential flux term made the largest contribution to the seasonal variation of EKE over the northern SCS, while the largest contributor was from the barotropic energy conversion term over the southern SCS. The months with the most active EKE coincided with the months with the maximum precipitation rate and TC formation number in both northern and southern SCS. TC formations over the SCS were closely related to the EKE tendency associated with the barotropic energy conversion. Regions of enhanced barotropic energy conversion favor the development of synoptic disturbances, which may further grow into TCs. By examining the relative importance of different components in the barotropic energy conversion term, the component associated with the shear of the zonal wind made the largest contribution over the northern SCS; by contrast, the largest contributor to enhanced barotropic energy conversions came from the component related with the convergence of the meridional wind over the southern SCS.?????
	TO cite this article:WANG Lei. Seasonal variation of the low-level atmospheric eddy kinetic energy over the South China Sea and its influences on the tropical cyclone genesis[OL].[29 June 2017] http://en.paper.edu.cn/en_releasepaper/content/4738238

Saved Papers

Saved Papers


	3. Using springtime Atlantic SST as a predictor for summertime western North Pacific subtropical high
	WANG Lei
	Earth Science 23 March 2017
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:The potential of using springtime Atlantic sea surface temperature (SST) to predict the intensity of summertime western north Pacific subtropical high (WNPSH) was examined. The results indicated that springtime north tropical Atlantic (NTA) SST had a close correlation with summertime WNPSH and could be used as a predictor. Since the early-1990s, the springtime NTA SST tended to have higher correlations with the WNPSH intensity, compared with other springtime predictors including the Indo-Pacific SST, El Ni?o-Southern Oscillation (ENSO) tendency and the North Atlantic Oscillation (NAO). Physically, the NTA SST could influence the WNPSH intensity by inducing the subtropical teleconnection and/or anomalous cross-basin vertical overturning circulation linking the tropical Atlantic and western Pacific. Both statistical relationship and underlying physical mechanism support the springtime NTA SST as a predictor for summertime WNPSH intensity. Including the springtime NTA SST as a predictor in the empirical prediction model could increase the prediction skill for summertime WNPSH intensity.?
	TO cite this article:WANG Lei. Using springtime Atlantic SST as a predictor for summertime western North Pacific subtropical high[OL].[23 March 2017] http://en.paper.edu.cn/en_releasepaper/content/4722971


	4. Association of the East Asian subtropical westerly jet with the Southwest Asian summer monsoon: A diagnostic analysis on heavy rain events in Yunnan Province, China
	CHEN Jie,JIN Liya
	Earth Science 23 February 2017
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:By using daily observations and the NCEP/NCAR reanalysis data during 1960-2011, a diagnostic analysis is performed to investigate the association of the East Asian subtropical westerly jet (EASWJ) with the Southwest Asian summer monsoon (SASM) on heavy rain events in Yunnan Province of southwest China during SASM prevailing season. The diagnostic analysis shows an anomalous divergence circulation pattern at upper level (200 hPa) over Eurasian continent that corresponds well to the negative anomaly of EASWJ intensity during the heavy rain events in boreal summer in Yunnan Province. Meanwhile, a low-level jet stream with abundant water vapor originated from the Arabian Sea and Bay of Bengal provides necessarily dynamic and water conditions for heavy rain mechanism. The study further shows that the weakening of the EASWJ during heavy rain events in Yunnan Province is associated with the decrease in the meridional air temperature gradient in northern mid-latitude (30o-45oN).
	TO cite this article:CHEN Jie,JIN Liya. Association of the East Asian subtropical westerly jet with the Southwest Asian summer monsoon: A diagnostic analysis on heavy rain events in Yunnan Province, China[OL].[23 February 2017] http://en.paper.edu.cn/en_releasepaper/content/4719965


	5. Estimation of surface solar radiation considering the distortion of cloud shadow on complex terrain
	Li Bin,Hu Jichao
	Earth Science 08 April 2016
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:Clouds and terrain are the two most important factors that affect the surface radiation, and cloud shadows are also an important influencing factor to estimate the surface radiation with remote sensing method. Cloud and its shadow under different observation angle and the angle of the sun will lead to 3-D geometry effect. Furthermore, the terrain also has influence on downward solar radiation. At the same time, the cloud shadow distortion under complex terrain also should be taken into consideration in the estimation of radiation. So "coupling" the clouds and the terrain under the certain condition has the vital significance on estimating the surface radiation values. Cloud detection results of high resolution satellite data was used, according to the height of the cloud and satellite observation angle information the position of cloud on the image was corrected to get the true position of the cloud. To more accurately describe the shadow distortion caused by the terrain, a geometrical method was used to calculate the true position of cloud shadows on complex terrain. On the basis of the result after the calculation of shadows, downward surface solar radiation of the corresponding position was calculated based on some parametric methods for clear and cloudy sky respectively. Then, according to the mountain radiative transfer theory, DEM and albedo was employed in the topographic correction model for the downward surface solar radiation (DSSR) calculated above. Finally, we made some comparisons between cloud shadows on smooth surface and complex terrain as well as DSSR without any correction and with correction of terrain effect. The results showed that it is necessary to make these corrections on complex terrain. There were some big differences of the DSSR distribution and values before making correction.
	TO cite this article:Li Bin,Hu Jichao. Estimation of surface solar radiation considering the distortion of cloud shadow on complex terrain[OL].[ 8 April 2016] http://en.paper.edu.cn/en_releasepaper/content/4683529


	6. The Characteristics of dust concertration and micrometeorology during dust storm events in arid area
	Zhu Hao,Liu Xinjian,Songxingzhuo,Zhang Hongsheng
	Earth Science 25 November 2015
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:Based on the data obtained during two dust storm events that occurred on 27 to 28 March 2004 and on 11 April 2006 from the dust storm monitoring tower located in Hunshandake sand desert and on Loess plateau, respectively, the relationships among dust concentration, micrometeorological characteristics and turbulent properties are investigated in this paper. And the threshold friction velocities for dust emission are estimated at the two sites. The values are 0.35 over the sand desert area and 0.52 over the Loess plateau, respectively.
	TO cite this article:Zhu Hao,Liu Xinjian,Songxingzhuo, et al. The Characteristics of dust concertration and micrometeorology during dust storm events in arid area[OL].[25 November 2015] http://en.paper.edu.cn/en_releasepaper/content/4664139


	7. Comparison of environmental conditions between a tropical cyclone active year and an inactive year over the South China Sea
	LI Hanzhou,WANG Lei
	Earth Science 19 May 2015
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:The South China Sea (SCS) experienced large variability in the numbers of tropical cyclone (TC) formations from year to year. Oceanic and atmospheric conditions were compared for an active TC activity year and an inactive TC activity year during the summer monsoon season (May to September) and the winter monsoon season (October to December): the summer of 2000 (seven TCs formed) and the summer of 1991 (0 TC formed); the winter of 1998 (six TCs formed) and the winter of 1991 (0 TC formed).The common environmental conditions which could account for the enhanced TC activity in the summer of 2000 and the winter of 1998 included: warmer SSTs, larger low-level relative vorticity, stronger mid-tropospheric ascending motion and lower outgoing longwave radiation (OLR). Larger mid-tropospheric moisture content and stronger upper-level divergence also provided more favorable conditions for TC formation during the winter of 1998, while these two factors could not account for the enhanced TC activity in the summer of 2000. These results suggest that there are some differences of the environmental conditions influencing TC activities in the SCS between in the summer monsoon season and in the winter monsoon season.
	TO cite this article:LI Hanzhou,WANG Lei. Comparison of environmental conditions between a tropical cyclone active year and an inactive year over the South China Sea[OL].[19 May 2015] http://en.paper.edu.cn/en_releasepaper/content/4644202


	8. One mechanism for tropical disturbance development over the South China Sea: Coupling of Lower-Upper Troposphere (CLUT)
	WANG Lei
	Earth Science 31 March 2015
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In this paper, one triggering mechanism (Coupling of Lower-Upper Troposphere (CLUT)) is proposed to explain tropical disturbance development and tropical cyclone formation over the South China Sea(SCS). The main contents of CLUT mechanism include: (1) Persistent large amount of latent heat release is the critical condition for tropical cyclogenesis and the amount of latent heat release determines one tropical disturbance to develop or not; (2) The Lower-Upper tropospheric coupling is necessary to generate large amount of latent heat release during tropical cyclogenesis; (3) The reasons why non-developing disturbances can not develop into tropical cyclones are due to the deficiency of lower-upper tropospheric coupling in dynamic conditions and/or in thermal conditions.
	TO cite this article:WANG Lei. One mechanism for tropical disturbance development over the South China Sea: Coupling of Lower-Upper Troposphere (CLUT)[OL].[31 March 2015] http://en.paper.edu.cn/en_releasepaper/content/4636942


	9. Deuterium Excess in Precipitation Indicating Vapor Origins over Southwest China
	ZHANG Xinping,ZHANG Xinzhu,WU Huawu,HUANG Yimin
	Earth Science 04 January 2011
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:In order to reveal the vapor origins of generating precipitation over southwest China, the variations of stable isotopes including deuterium excess d and the relationships of the stable isotopes with temperature and humidity at Mengzi, Tengchong and Puer sampling stations are analyzed. Under the monsoon system, d in precipitation has distinct seasonality with lower values in the rainy season and higher values in the dry season. Analyses show that the relationship of d in precipitation with temperature and humidity in the middle and low troposphere has consistency. If taking into account the relationships of d and δ18O in precipitation with atmospheric humidity synthetically, it can be deduced that the main causation of affecting stable isotopic variations in precipitation over southwest China is related to the property of rainfall air mass, whereas the evaporation enrichment action in falling raindrop is relatively light. In the rainy season of southwest China, the vapor of generating precipitation, with high humidity, low stable isotopic ratios owing to the rainout of vapor on the transport way, and small d-values in precipitation, is primarily from low-latitude oceans; in the dry season, the vapor of generating precipitation, with low humidity, great stable isotopic ratios and high d-values in precipitation, is primarily from the westerlies transportation and the replenishment of re-evaporated vapor in inland.
	TO cite this article:ZHANG Xinping,ZHANG Xinzhu,WU Huawu, et al. Deuterium Excess in Precipitation Indicating Vapor Origins over Southwest China[OL].[ 4 January 2011] http://en.paper.edu.cn/en_releasepaper/content/4403978


	10. Change in surface latent heat flux over the tropical Pacific
	REN Baohua,LI Gen
	Earth Science 21 December 2010
	Show/Hide Abstract \| Cite this paper︱Full-text: PDF (0 B)

	Abstract:Using the Objectively Analyzed air-sea Fluxes (OAFlux) data, we have revisited the causes of the tropical Pacific surface latent heat flux (LHF) trend during 1977-2006. It is suggested that the LHF presents a statistically significant positive trend and its pattern is related to both the ocean warming and the surface wind strengthening. The ocean warming is the direct cause of the LHF trend, while the surface wind strengthening, due to its contribution to the sea surface temperature (SST) trend pattern, is the indirect cause of the LHF trend.
	TO cite this article:REN Baohua,LI Gen. Change in surface latent heat flux over the tropical Pacific[J].

	Check out RSS, or use RSS reader to subscribe this item