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Enlargements of the results shown in Fig. 22. The left panels are from the same simulation in Fig. 22, which takes a midlevel relative humidity of 75 , whereas for the right panels the relative humidity is increased by 5 . Top two panels show the evolution of relative humidity (solid lines) and relative acidity in the Wanli aerosol (dashed lines) and NTU aerosol (dotted dashed lines) scenarios. The middle and bottom panels show the evolution of aerosol number concentration in the...

O3NO2 vs observed NOx and NMHCs R2 0

Same as Fig. 4 except that the horizontal coordinates are changed to O3 precursors observed at the daily maximum values of O3 + NO2, which are plotted as the vertical coordinate. Figure 6. Same as Fig. 4 except that the horizontal coordinates are changed to O3 precursors observed at the daily maximum values of O3 + NO2, which are plotted as the vertical coordinate. PKU 14-11, 13-10, and 12-9 (3hrs, 58 points) Figure 7. Same as Fig. 4 except for the Peking University station during the...

E 90e 135e 180 135w 90w

Note that the El Nino-like case discussed here does not correspond to either the ENSO growing or decaying phase, because the experiments here are all at equilibrium. The monsoon has great differences in detail in different regions, but at its heart is the seasonal movement of land convection zones. The convection is directly affected by evaporation in the moisture equation (2). More importantly, it is also associated with a dynamical feedback via the net energy into the atmosphere...

G No ventilation and nobetah No ventilation and partialbeta

The term v V(T + q) includes two components the moisture transport v Vq and the temperature transport v VT. To examine the effects of these two components respectively, v VT and v Vq are suppressed separately in Figs. 6(d) and 6(e). When v VT is suppressed, the Asian summer monsoon rain zone does extend a little northward, but concentrates over the southeastern part of Asia Fig. 6(d) . The amplitude of the monsoon rainfall does not show any sign of enhancement. When v Vq is suppressed, on the...

Jf vV2Z2 dxdy5

The last term in (5), which represents the effect of mixing, is always negative mixing always reduces the overall vorticity gradient in the domain. The first term on the right hand side of (5), which represents stirring, is usually positive. The reason is that, in an average sense, positive local vorticity extremes (i.e. V2Z < 0) near the typhoon core are likely to be coupled with the positive vorticity advection (i.e. 'yj < 0). In other words, stirring directly increases the palinstrophy....

M

Summary of the Rankine vortex binary interaction regimes as a function of the dimensionless gap A Rl, and the vorticity strength ratio 7 C2 for the radius ratios r Rl R2 1 2, 1 3, and 1 4. As indicated by the code at the lower right, the structures are categorized as follows elastic interaction (EI), merger (M), straining-out (S), tripole (T), concentric (C). The concentric regime is shadowed. (Adapted from K04.) There are observations and model simulations of binary tropical cyclone...

Air Sea Exchange and Ocean Mixing at the Diurnal and Intraseasonal Scales

Lau and Sui (1997) and Sui et al. (1997b) analyzed the COARE data and found that the dry and wet phases in the atmospheric precip-itable water are associated with the passage of the intraseasonal oscillations during the TOGA COARE. The passage of the intrareasonal oscillations also affects the surface radiative and heat fluxes that impact the ocean mixing processes and thus the upper-ocean stratification. The 2-3-day disturbances and diurnal cycles are phenomena with the dominant time scales...

E 60e 90e 120e 150e 180 150w 120w 90w 60w

Precipitation climatology (1979 2004) in (a) the boreal summer (JJA) and (b) the boreal winter (DJF) from the Climate Precipitation Center (CPC) Merged Analysis of Precipitation (CMAP Xie and Arkin, 1997). Plateau. The Asian summer monsoon has several subregional systems, including the Indian summer monsoon, the western North Pacific summer monsoon, and the East Asian summer monsoon (Goswami et al., 1999 Lau et al., 2000 Wang and Fan, 1999 Wang and LinHo, 2002). Each subregional...

Part

Atmospheric Dynamics and Meteorology Understanding the El Nino Southern Oscillation and Its Interactions with the Indian Ocean and Monsoon Department of Earth System Science, University of California, Irvine, California, USA The Pacific and Indian Oceans are closely linked to each other through atmospheric circulation and oceanic throughflow. Climate variations in one ocean basin often interact with those in the other basin. This includes phenomena such as the El Nino-Southern Oscillation...

VsDLMq I I VsDLM qB

Where q'A(q'B) represents the perturbation PV of storm A (B), while r c, r a, and r B stand for the position vectors of the centroid, storm A, and storm B, respectively. (1) PV diagnostics of the motion of Hurricane Bob (1991), Tropical Storm Ana (1991), and Hurricane Andrew (1992) (Wu and Emanuel, 1995a,b) In Wu and Emanuel (1993, 1994), the results of the advection flow of Bob show that Bob's movement is due not only to the climatological (July-September) mean balanced flow, but also to...

Abrupt Latitudinal Movement of the ITCZ Monsoon Onset

Itcz Movement

The intertropical convergence zone (ITCZ) is the location where surface winds converge and rise into the upward branch of the Hadley Walker circulation. The latent heat released in the ITCZ drives the Hadley Walker circulation. In other words, the ITCZ is a part of the Hadley Walker circulation. The latitudinal location and the intensity of the ITCZ impact the tropical surface wind distribution, which, in turn, impacts the air-sea interaction. The latter is known to play a crucial role in El...

S

Then the lowering of relative humidity forces the unnucleated cloud drops and aerosols to evaporate and become more concentrated, such that they are more difficult to freeze. So, the microphysical properties of high-altitude ice clouds depend very much on the chemical and physical properties of the aerosols. Besides the freezing mechanism, hygroscopic aerosols may aid the formation of ice by taking on the role of INs. Abbatt et al. (2006) pointed out that dry...

Ch3ooh ch2o hcooh ch3cooh so2

SO4 and CRESOL are assumed to be 5 days (Logan et al., 1981). Results of the layer of 16 m height, at which most surface measurements were made, are used to make a comparison with measurements at surface stations and the OBM results. The emission rates of O3 precursors are based on the Taiwan Emission Data System (TEDS 5.0, 2000) published by the TEPA (http www.aqmc.org.tw). Area and line sources in the KaoPing area are averaged to obtain the average emission rates. The emission rates of NOx,...

Representation of Convective Radiative Processes in Climate Models

The research results discussed in this review represent a one-way interaction approach for process models to study the physical processes interacting with climate oscillations. The acquired knowledge forms a basis for improving the representation of these physical processes in climate models, and also motivates the next-step approach to examining the radiative-convective (two-way) interaction with climate dynamics in large-scale models. Indeed, since the original attempt by Sundqvist (1978) to...

E Advq 1000200 hPa diff

Termed the interactive Rodwell-Hoskin (IRH) mechanism, while the advection associated with the cross-continental winds is termed ventilation. Thus, the local effects of evaporation and Fnet initiate the convection and the effects of ventilation, and the IRH mechanism modifies the summer monsoon rainfall pattern. In this study, we first analyzed the local effects, including evaporation and the dynamical feedback of Fnet. The evaporation over land is associated with soil moisture. Soil moisture...

Precipitation efficiency

Precipitation efficiency is an important physical parameter for measuring the interaction between convection and its environment (Doswell et al., 1996 Ferrier et al., 1996 Tao et al., 2004). Its definition may vary. For large-scale applications involving cumulus parametrization (e.g. Kuo, 1965, 1974), the precipitation efficiency is defined as the ratio of the surface rain rate to the sum of the surface evaporation and vertically integrated moisture convergence, and is referred to as...

Outbreaks of Asian Dust Storms An Overview from Satellite and Surface Perspectives

Dust Storm China Graph

Laboratory for Atmospheres, Goddard Space Flight Center, Greenbelt, Maryland, USA Taiwan, located downwind of dust storm outbreaks from China, in the sink region of biomass-burning aerosols from Southeast Asia, and at the outflow of urban-industrial pollutants from the Pearl and Yangtze River Delta, is exposed to a seasonal milieu of natural and anthropogenic aerosols in the atmosphere. In the springtime, outbreaks of Asian dust storms occur frequently in the arid and semiarid areas of...

Conclusions and Discussion

This study has revealed the strong ISO-TC in-phase relationship in the tropical western North Pacific during JJASO 2004. The repeated appearance of the ISO during JJASO resulted in the fluctuation of the EA monsoon trough and the Pacific anticyclone, which in turn modulated the TC activity and led to the spatial and temporal clustering of TCs. While TCs occurred in groups during the cyclonic phase of the ISO, the clustering of these strong TC vortices significantly increased the overall...

Diurnal variation of tropical oceanic convection

Oceanic Convection

The diurnal variation of tropical oceanic convection is one of most important phenomena in tropical variability, and plays a crucial role in regulating tropical hydrological and energy cycles. The dominant diurnal signal is the nocturnal peak in precipitation that occurs in the early morning (see the review in Sui et al., 1997a). Kraus (1963) emphasized the role of radiative forcing in the diurnal variation, and suggested that solar heating and IR cooling tend to suppress convection during...

Linear Instability

It is instructive to first examine the dynamical properties of weak perturbations in this system. They are governed by the linearized version of (6.2), viz. Zt + J( ref, Z) + JW, Cref + f) aC (4) The absolute vorticity and stream function fields of a pertinent basic state with uoo 0.2 are shown in Fig. 1. The maximum nondimensional velocity is 1.05. The model Pacific jet has a maximum speed of 63m s and the model Atlantic jet has a maximum speed of 37m s. The two localized jets are made up of a...

References

P., 1988 Introduction to Micrometeorology. Academic, New York, 307 pp. Black, R. X., and R. Dole, 2000 Storm tracks and barotropic deformation in climate models. J. Climate, 13, 2712-2728. Chang, E. K. M., S. Lee, and K. Swanson, 2002 Storm track dynamics. J. Climate, 15, 21632183. Deng, Y., and M. Mak, 2005 An idealized model study relevant to the dynamics of the midwinter minimum of the Pacific storm track. J. Atmos. Sci., 62, 1209-1225. Lee, S., 2000 Barotropic effects on...

Cyclall

Moreover, the temporal distribution of the soundings data is not homogeneous. It varies from zero at 0600 UTC 13 September to 13 soundings at 1600 UTC 13 September. A total of seven experiments are conducted (see Table 1). The schematic diagram of all dataassimilation experiments is shown in Fig. 3, and the experimental domain is shown in Fig. 2(a) with the size of 222 x 128 in a 45 km grid distance. There are a total of 45 full vertical model levels with the n values of 1.0, 0.995,...

An Overview of Satellite Measured Cloud Layer Structure and Cloud Optical and Microphysical Properties

Fu-Lung Chang Langley Research Center, NASA, Hampton, Virginia, USA Fu-Lung.Chang-1 nasa.gov Satellite observations are the only means of obtaining a continuous survey of cloud properties on global scales. Many climate and weather forecasting models have been evaluated using satellite-derived products. For clouds, the evaluation has been limited mainly to cloud amount, in part because conventional satellite remote sensing techniques cannot provide detailed information on cloud vertical...

Polar ice cap instability in energybalance climate models

This best-known example of a catastrophe in climatology is found in energy-balance climate models. Budydo (1969) and Sellers (1969) demonstrated, in a one-dimensional model, a catastrophic transition from a globe that has ice in the polar regions only to an ice-covered globe by lowering the solar constant by a few percent. A description of this catastrophe can be found in textbooks on climatology, such as Hartmann (1994). Ocean-atmosphere interaction gives rise to additional catastrophes. The...

E No qventilation

July precipitation for experiments over the Asian region (a) control run, (b) saturated soil moisture, (c) no ventilation, (d) no T ventilation, (e) no q ventilation, (f) no 3, (g) no ventilation and no 3, and (h) no ventilation and partial 3 (from CN03). Figure 6. July precipitation for experiments over the Asian region (a) control run, (b) saturated soil moisture, (c) no ventilation, (d) no T ventilation, (e) no q ventilation, (f) no 3, (g) no ventilation and no 3, and (h) no...