Iso 165

Cross section of the simulated (a) 9v, (b) total water content qw, (c) vertical velocity w. The intrusion of the moisture is much deeper than the potential temperature field along the dryline (Sun and Wu, 1992). Figure 3. Cross section of the simulated (a) 9v, (b) total water content qw, (c) vertical velocity w. The intrusion of the moisture is much deeper than the potential temperature field along the dryline (Sun and Wu, 1992). Figure 4. (a) Locations of the cyclones at 6-hr...

Mm5

Coordinate Equations Time differencing advection Timesplitting Local reference Ice equivalent temperature dei Based on dei and total water substances Potential temperature Based on temperature the prognostic equations for momentum ice-equivalent potential temperature 9ei turbulent kinetic energy (TKE) surface pressure all phases of water, including ice, liquid, snow, rain, graupel, and vapor (Lin et al., 1983 Chern, 1994 Haines et al., 1997 Chen and Sun, 2002) and multilayers of soil...

Ii

Always exists in weather climate models, which can be caused by errors in equations, physical parametrizations, resolution, initial and boundary conditions, numerical methods, etc. (Sun, 2006a,b). Received 19 January 2007 Revised 19 October 2007 Accepted 23 October 2007. Anthes, R. A., 1977 A cumulus parameterization scheme utilizing a one-dimensional cloud model. Mon. Wea. Rev., 105, 270-286. Bosilovich, M. G., and W. Y. Sun, 1995 Formation and verification of a land surface parameterization...

Dvar

Horizontal and vertical resolution (see Table 2). Furthermore, as mentioned, by the time the ERS-1 scatterometer wind data were ready for a preimplementation test in the early 1990's, the atmospheric analysis scheme also changed from an OI scheme into a spectral statistical interpolation scheme (Derber and Parrish, 1991 Parrish and Derber, 1992), which is essentially a three-dimensional variational analysis scheme (3D-VAR). It is important to note that the beginning of the operational use of...

Sumatra Island

Serveteliu Nerimas Schemos

Japanese Geostationary Meteorological Satellite image at 0232 UTC 27 December 2001. All national weather services in the region reported it as a tropical storm. (e.g. DeMaria and Pickle, 1988), the spiral cloud bands emanating out from around the center clearly indicate that the storm circulation was on both sides of the equator. Figure 6 shows the Japanese Geostationary Meteorological Satellite image at 0232 UTC of the same day. Feeder bands from both sides of the equator spiral into...

Info

To remedy the deficiency associated with the Goodberlet algorithm mentioned above, Krasnopolsky (1995a, 1995b) developed nonlinear algorithms based on neural network architectures, which were shown to be capable of modeling the nonlinear dependence of wind speed on brightness temperatures. The performance of neural network algorithms in the retrieval of SSM I wind speed data discussed in Krasnopolsky (1995a, 1995b) has been tested mainly by using a well-prepared matchup database, i.e. their...

X

Distribution of nondimensional average kinetic energy of the fluctuations for the case of a 0.03. value 0.11 vs 0.09). The exit region of each modified background jet, on the average, is therefore more diffluent than the corresponding jet in the reference state. There would be stronger local stretching deformation in the exit region of each jet, which contributes to a stabilizing influence on the eddies. The meridional shear on both sides of each jet is also reduced. Such feedback...

Days

Same as Fig. 5(a) except that the values of 90 and 95 are switched. wind speed used in computing the surface sensible and latent fluxes is fixed at 5m s everywhere. Because curve B has been eliminated, the ITCZ is located at the equator. A further experiment shows that radiation can have impact on the ITCZ location through its effect on N2 and in turn on curve B. Different radiation packages lead to different amounts of forcing for the cumulus convection, resulting in differing...

Coupled Boundary Layer and Forced Oceanic Responses

Sui et al. (1991) developed an equilibrium model to study the coupled ocean-atmosphere boundary layer in the tropics, which consists of a one-dimensional thermodynamic atmospheric model for a partially mixed, partially cloudy convective boundary layer (CBL), Betts and Ridgway, 1988 1989 and an oceanic mixed-layer (OML) model. Two experiments were performed with sea surface temperature (SST) specified. They solve the equilibrium state of the coupled system as a function of SST for a given...

R2 A

With each vortex (DeMaria and Chan, 1984). In addition, the radial vorticity gradient associated with the vorticity skirt provides a means for the radial propagation of vortex Rossby waves (Montgomery and Kallenbach, 1997 Balmforth et al, 2001). Finally, skirted vortices can be more resilient to the destructive effects of large-scale vertical wind shear (Reasor et al., 2004). As far as the concentric eyewall fomation dynamics are concerned, the skirt on the core vortex provides a shielding...

Numerical Experiment

The empirical results presented above reveal the significant effect on the amplitude and variance of the ISO. This section presents numerical simulations performed to see whether similar effects could be realized in the numerical models. Two models were used in this study. The first was the Purdue regional model (PRM), which had been used for the study of various mesoscale phenomena (e.g. Sun et al., 1991 Hsu and Sun, 1994 Sun and Chern, 1993) and climate simulation (e.g. Bosilovich and Sun,...

Impact of Formosat3Cosmic Data on Typhoon and Meiyu Prediction

Wrf Typhoon

Ying-Hwa Kuo, Hui Liu and Yong-Run Guo National Center for Atmospheric Research, Boulder, Colorado, USA Chuen-Teyr Terng and Yun-Tien Lin Central Weather Bureau, Taipei,, Taiwan The Formosa Satellite Mission 3 Constellation Observing System for Meteorology, Ionosphere and Climate (FORMOSAT-3 COSMIC), hereafter referred to as COSMIC, is a Taiwan-US mission launched in April 2006. COSMIC consists of six small satellites that employ the Global Positioning System (GPS) radio occultation (RO)...

Ab

Mucosa Diagram

Simulated -component wind for a 2-km mountain after 2.5 h of integration (a) free-slip surface and (b) rigid surface (Hsu and Sun, 2001, and Sun and Hsu, 2005). Figure 14. Simulated -component wind for a 2-km mountain after 2.5 h of integration (a) free-slip surface and (b) rigid surface (Hsu and Sun, 2001, and Sun and Hsu, 2005). applied this model to study the flow over an idealized, bell-shaped mountain under different environments. With the use of an open lateral boundary and a...

Tj200308300908

Ocean Eddy Structure

The pre-Maemi SSHA map (based on the 30 August-8 September 2003 cycle of TOPEX Poseidon and Jason-1 measurements) showing the warm ocean eddy (characterized by a positive SSHA of 10-45 cm). Maemi's track, intensity (on the Saffir-Simpson scale, illustrated as color bullets) and radius of maximum wind are also shown. The storm position is denoted every 6h. (After Lin et al., 2005.) Using a simple coupled typhoon-ocean model, i.e. the CHIPS (Coupled Hurricane Intensity Prediction...

Tropical Cyclogenesis

Tropical cyclogenesis is the transition from a cloud cluster to a tropical cyclone (TC). Prior to the transition, the cloud cluster can last for days with little change in its characteristics. Thus, one can claim that the cloud cluster is in a quasi-equilibrium state. After the transition, the tropical cyclone can also last for days without changing its basic characteristics. Hence, one can identify the tropical cyclone as a quasi-equilibrium state as well. Tropical cyclogenesis typically takes...

Y

Each integration lasts for 1800 nondimensional time units (equivalent to 354 days). Let us first consider a control run in which we use uoo 0.2 with a uniform friction coefficient for the whole domain, a 0.03. The Figure 4. Distribution of eigenvalues of normal modes under the influence of differential friction (aocean 0.015, aland 0.045). The unit of time is LU-1 0.17 x 105 s. Figure 4. Distribution of eigenvalues of normal modes under the influence of...

Forecast Time

Figure 6. (a) Track of cycling data-assimilation experiments, including DARTNBNG, DARTNB, CYCLNBNG, CYCLNB, and the best track the SLP field is obtained from the DARTNBNG at 0000 UTUC 14 September 2006 (b) the corresponding central pressure time series and (c) track forecast errors for the four cycling data-assimilation experiments. storm, with a radius of maximum wind of about 350 km and the maximum tangential wind just a little over 10 ms-1. The assimilation of GPSRO soundings does not seem...

Iodo

Variations of the rate change of Nccn as a function of Nccn for different production strengths. The zero intercept represents an equilibrium condition, but only those marked by black dots are stable modes where any deviation from that Nccn value will eventually return to the stable conditions. (From Fu, 2002.) Figure 3. Variations of the rate change of Nccn as a function of Nccn for different production strengths. The zero intercept represents an equilibrium condition, but only those...

Sondjfmamj Ja

Temporal evolutions of the IMRI (thin-solid), AMRI (thin-dashed), central Pacific SST (Pac-SST thick-dashed), and central Indian Ocean SST (Indo-SST thick-solid) during the (a) in-phase monsoon transition and (b) out-of-phase monsoon transition. All values are composited from the Indo-Pacific Run.

C AdvT 1000200 hPa diff

Differences between surface albedo Rs 0.15 and Rs 0.25 (control run) for (a) July precipitation and winds at 850 hPa (from CN03), (b) the upper tropospheric temperature (from CN03), (c) horizontal advection of temperature v VT) and (d) horizontal advection of moisture v Vq). Figure 7. Differences between surface albedo Rs 0.15 and Rs 0.25 (control run) for (a) July precipitation and winds at 850 hPa (from CN03), (b) the upper tropospheric temperature (from CN03), (c) horizontal...

Relevance to Climate Variability and Future Perspectives

In this article, the authors' research results in the past 15 years in the tropics are highlighted. Reviewed are convective-radiative processes including climate equilibrium study, tropical convective responses to radiative and microphysical processes, the diurnal cycle, cloud clustering and associated cloud-microphysical processes, precipitation efficiency, air-sea exchanges and ocean mixing processes at diurnal-to-intraseasonal scales, and coupled boundary layer and forced oceanic responses....

Annulus experiments

The various flow regimes in annulus experiments show a considerable amount of overlap in the regime diagram (Lorenz, 1967 Holton, 2004) and the transition among them is often quite abrupt. Routes to turbulence have many catastrophes. The stratospheric sudden warming mechanism reviewed in Sec. 3 has been used to explain Martian polar warming (Barnes and Hollingsworth, 1987). Dust storms lasting months can engulf nearly the whole Martian atmosphere within weeks of their onset. Their growth is...

Equatorial Pacific

Summary diagram for the convective radiative-mixing processes in the tropical ocean atmosphere. intraseasonal oscillations in the warm pool region illustrated in Fig. 3. Because the precipitation rate is greater than the evaporation rate over the equatorial western Pacific warm pool, whereas it is smaller over the eastern Pacific, a barrier layer appears year round within the warm pool (e.g. Lukas and Linstrom, 1991 Ando and McPhaden, 1997 Vialard and Delecluse, 1998ab). The barrier...

KH2 O [H2 0CH 2O

Where ki and kH2 o are the precipitation frequency (or rate) of a chemical species i and water, respectively variables in square brackets denote the species concentration in the precipitation and C represents the concentrations in the air. Figures 20(b)-20(c) show the ER of various trace chemicals due to scavenging by liquid phase and ice phase precipitation, respectively, from the orographic clouds shown in Fig. 19. Note that since essentially all sulfate exists in aerosol or cloud droplets...

Introduction

Changes in the physical world are of two basic types gradual and sudden. Gradual changes are the norm sudden changes are less frequent, larger in magnitude, and easily recognizable. A physical system may experience gradual change over a long period of time, and then all of a sudden, a rapid change may occur. For example, at a typical tropical island station in the Caribbean, the surface air temperature gradually rises after sunrise and continues to rise till late afternoon, but then suddenly...

Iiiiiii

Vortex emergence and evolution for two different initial vorticity spatial scales, r* 1 (5 10 km scale) and r* 4 (30-40km scale). core vortices are used in the experiments. The parameter y is now taken to be the ratio of the vorticity in the core vortex to the peak turbulent background vorticity, which is set to 3x 10-3s-1. This is the same amplitude used for the companion vortex in the binary vortex experiments. We have avoided the use of stronger turbulent background vorticity in...

HNO3gHNO3all

Partition of sulfuric acid and nitric acid between the gas phase and the liquid phase as a function of atmospheric liquid water content and droplet pH. The vertical axis is the fraction of these acids that exists in the gas phase. type aerosols, from which sulfate was produced in particles but outside of the light-scattering size range. In the above we discussed the modification of aerosol composition and size distribution through the combination of cloud chemistry and two...

Cloudresolving modeling for climate equilibrium and feedback study

Lau et al. (1993) and Sui et al. (1994) studied tropical water and energy cycles, and their roles in the tropical convective systems, by integrating the two-dimensional cloud-resolving model to the climate equilibrium states. The model is imposed with a time-invariant, horizontally uniform, large-scale vertical velocity and a fixed SST at 28 C, in which the simulated atmosphere is conditionally unstable below the freezing level and close to neutral above the freezing level. After the...

O

Schematic illustrating the relationship between the Indian Australian summer monsoons and the Indo-Pacific Ocean SST anomalies (SSTA) during the TBO. anomaly pattern typically associated with a strong Indian monsoon in June-July-August (JJA, Year 0) (Lau and Yang, 1996). The strong monsoon winds force the Indian Ocean SST anomalies to reverse sign. The Indian Ocean SST anomalies in September-October-November (SON, Year 0) are, therefore, in transition and have small amplitudes....

Req lm

Modified K hler curves and the hysteresis cycle. The blue curves are the modified K hler curves the green curves are the traditional K hler curves, except below the spontaneous dehydration point, SSpon the upper dotted line indicates the Kelvin effect, and the lower dotted line connects the deliquescence part of each curve, the end of which is the common or bulk deliquescence point, Sdeliq,b. The thin solid line shows the growth path of dry aerosols (from point D) in moisturizing air...

Modelyear

NINO3 SST anomalies calculated from (a) the Pacific Run and (b) the Indo-Pacific Run. These monthly values are low-pass filtered to remove variations shorter than 12 months. (From Yu et al., 2002.) Figure 6. NINO3 SST anomalies calculated from (a) the Pacific Run and (b) the Indo-Pacific Run. These monthly values are low-pass filtered to remove variations shorter than 12 months. (From Yu et al., 2002.) interannual variability in the Indian Ocean and its interactions with the ENSO...

Ecmwf

Ten day mean wind vector and isotachs (ms 1) at 850 mb for the first 10 days of June, July, and August of 1998 (Sun and Chern, 1999). Figure 8. Ten day mean wind vector and isotachs (ms 1) at 850 mb for the first 10 days of June, July, and August of 1998 (Sun and Chern, 1999). 850 hPa subtropical high, (2) a stronger barocli-nicity around 40 N over eastern Asia and a low pressure located to the north of the front, and (3) excessive evaporation from the abnormally wet, warm land (Sun,...

Iiii

Turbulent background experiments for the (1) straining-out case (r* 1, 7 2), (2) merger case (r* 4, 7 2), (3) tripole case (r* 4, 7 2), and (4) concentric case (r* 4, 7 6). A vorticity clear zone (moat) of 10 km is introduced near the core vortex for the last two experiments. vorticity of alternate signs, with the whole configuration steadily rotating in the same sense as the vorticity of the elliptically shaped central core (Carton et al., 1989 Polvani and Carton, 1990 Carton and...

Stratospheric Sudden Warming

In the polar region of the stratosphere, the temperature in winter can rise by more than 40 K in as little as a week followed by a substantial drop, which is just as fast. The corresponding zonal mean zonal wind, consistent with the thermal wind relationship, can turn easterly in a major warming event. This phenomenon is called stratospheric sudden warming (SSW). It may occur more than once during a winter the last episode, called the final warming, is often the strongest and precedes the...

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.)

B Constant Rs

July precipitation for experiments over the African region (a) control run and (b) constant surface albedo over Africa (from CN03). Figure 4. July precipitation for experiments over the African region (a) control run and (b) constant surface albedo over Africa (from CN03). effect associated with cross-continental flow is termed ventilation, and the interaction of the summer monsoon heating with its circulation is termed the interactive Rodwell-Hoskins (IRH) mechanism (CNS). To study...

Contour From 1 To 1 By

Figure 19. (a) Horizontal plane of numerical simulation and (b) vertical profiles of analytic solution (dashed line) and numerical result (solid line) of Doswell's idealized cyclogenesis after 16 time steps with courant number 4.243, revolution 4.386 and S (transition width) 2.0 with mass correction but without internet filter (Sun and Sun, 2004). Oh (2007) applied the semi-Lagrangian integration method (Sun et al., 1996 Sun and Yeh, 1997) combined with the method of characteristics to the 2D...

TC Contribution to the ISV

The potential contribution of TCs to the ISV was estimated by calculating the difference between the ISV was the original and the TC-removed vorticity at 850 hPa. As demonstrated in Fig. 2 and Hsu et al. (2008), the Kurihara scheme cleanly separates TCs from the background large-scale circulation. The variance contributed by TCs and large-scale circulation are also well separated. The original 32-76-day variance of 850 hPa vorticity presented in Fig. 8(a) reveals two major ISV regions along the...

References

Sun, 1998 Monthly simulation of surface layer fluxes and soil properties during FIFE. J. Atmos. Sci., 55, 1170-1184. Bosilovich, M. G., and W.-Y. Sun, 1999 Numerical simulation of the 1993 Midwestern flood land-atmosphere interactions. J. Climate, 12, 14901505. Chen, T. C., S. Y. Wang, M.-C. Yen, and W. A. Gallus Jr., 2004 Role of the monsoon gyre in the interannual variation of tropical cyclone formation over the western North Pacific. Weather and Forecasting, 19,...

Droplet

Schematics of the interactions between iron and sulfur cycles. Solid arrows indicate conversions, while dotted arrows indicate influences. clouds may induce similar effects by influencing NOk-related chemistry. 3.1. Microphysical and chemical modifications Cloud water is an effective medium for chemical reactions. It can absorb trace gases, and dissociate them into ionic species, which may then react to form new species. Some of the aqueous phase reactions dominate the production or...

VsDLM a VsDLMty Vsdlm

Where Vsdlm(qa) and VsDLM(q') are as defined in Eq. (5). Note that by definition, AT(q') AT( qa ) + AT(qn (4) Defining the new centroid for plotting the centroid-relative track Conventionally, the centroid-relative tracks based on geography centers are often plotted to illustrate the binary interaction. This picture is often misleading, since the actual binary interaction is generally a function of the strengths of both vortices, and would not rotate with respect to the geographic center...

R T

Where Lv is the latent heat of condensation, Rv is the gas constant of water vapor, Ta is air temperature, AT Q 4nrka is the temperature rise under a BC heating rate of Q, r is the drop radius and ka is the thermal conductivity of air ( 0.0238 Wm-1 K-1 at 0 C) corrected with the gas kinetic theory. With a 50 BC content, AT is about 0.02 K for 1 m aerosols and 0.1 K for 10 m aerosols. Note that, as will be mentioned later, the heating rate is significantly stronger if the aerosols are wet. The...

S

Hodograph of the Earth-relative horizontal winds and its deep-layer mean obtained from the VTD analysis (VM) and the 12-hour mean motion of Hurricane Gloria (1985), VH. (From Lee et al., 1994.) GBVTD analysis, Typhoon Nari (2001) using the EGBVTD technique (Liou et al., 2006), and Cyclone Tina (2002) (Roux et al., 2004) using the GB-EVTD technique. The structures of these landfalling TCs were consistent with previous studies but revealed detailed evolution of TCs ( 6-15 minute...

T oC

Figure 5. d ln L dTc and Tc adapted from the adiabatic cloud liquid water content of Betts and Harshvandhan (1987) (open squares) and the subadia-batic cloud liquid water content of Somerville and Remer (1984) (solid squares). The lines represent the polynomial regression fits to the individual dataset. With the values of d ln T dT being negative, the values of dln L dT being positive, and the values of dln re dT being near zero, the values of d ln D dT are expected to be negative. Figure 6...

C V2

A fourth-order hyperdiffusion with a coefficient r 2.5 x 10 4 is incorporated in the model for computational purposes. The frictional effect is represented by a linear drag. It may be viewed as a linearized form of a bulk aerodynamic formula for representing a surface stress. A reasonable value of the drag coefficient is a 0.03, corresponding to a damping time of about 5 days (Whitaker and Sardeshmurkh, 1998). When we take into account the influence of continents and oceans, we use a 0.015 in...

Cloud clustering and

Lau et al. (1991) analyzed infrared radiance measurements at the cloud top from the Japanese GMS to study the structure and propagation of tropical cloud clusters over the equatorial western Pacific. The observed cloud clusters display a hierarchy of collective motions at time scales of 1 day, 2-3 days, and 10-15 days, respectively. The 1-15-day time scale is closely related to the intraseasonal oscillation, and their super cloud clusters propagate eastward along the equator from the Indian...

So 90 120 Iso Iso 210 240 270 30090 60 90 120 160 160 210 240 270 30ib0 So 90 120 Iso 180 210 240 270 300

Ocean model domains used in the (a) Indian Ocean Run, (b) Indo-Pacific Run, and (c) Pacific Run. Also shown are the long-term mean SST's produced by these runs. Contour intervals are 2 C. Values greater than 28 C are shaded. The UCLA CGCM has been shown to produce a realistic seasonal cycle in the tropical eastern Pacific (Yu et al., 1999) and is considered one of the few coupled models capable of producing realistic ENSO simulations in an inter-comparison project of ENSO simulation...

Acknowledgements

We thank the two anonymous reviewers for their constructive comments, and are grateful for the continuous support of our research from the National Research Council in Taiwan, the National Aeronautics and Space Administration, the National Science Foundation, and the National Ocean and Atmosphere Administration in the US in the past 15 years. The GCE modeling work is mainly supported by the NASA Headquarters Physical Climate Program and the NASA TRMM. In particular, Dr. R. Kakar at NASA...

MD Chou

National Taiwan University, Taiwan Executive Editor NEW JERSEY LONDON SINGAPORE BEIJING SHANGHAI HONG KONG TAIPEI CHENNAI World Scientific Publishing Co. Pte. Ltd. 5 Toh Tuck Link, Singapore 596224 USA office 27 Warren Street, Suite 401-402, Hackensack, NJ 07601 UK office 57 Shelton Street, Covent Garden, London WC2H 9HE Library of Congress Cataloging-in-Publication Data Recent progress in atmospheric sciences applications to the Asia-Pacific region edited by K.N. Liou and M.-D. Chou. p. cm....

Maximum Vector

Radial flows superimposed on the radar echoes over the area surrounding the bow-shaped and sausage-shaped echoes. (b) Vertical structure of the secondary circulation wind vectors composed of the east west divergent and the vertical velocities. (From Lee et al., 2005.) Figure 18. Radial flows superimposed on the radar echoes over the area surrounding the bow-shaped and sausage-shaped echoes. (b) Vertical structure of the secondary circulation wind vectors composed of the east west...

P Ox

The net Ox production derived from observation of A Ox is equal to the gross Ox production minus the gross photochemical loss, deposition and dispersion of Ox. is the ozone production efficiency. It is the number of O3 molecules produced per molecule of NOx consumed photochemically and a key factor in understanding the photochemical formation of O3 (Liu et al., 1987 Trainer et al., 2000). Typical values of over the US are in the range of 1-20mol mol (Jacob, 1999). The most straightforward way...

Year

Evolution of anomaly correlations for 500 hPa geopotential height forecasts at NCEP for the northern and southern hemispheres. Figure 2. Evolution of anomaly correlations for 500 hPa geopotential height forecasts at ECMWF for the northern and southern hemispheres. Figure 2. Evolution of anomaly correlations for 500 hPa geopotential height forecasts at ECMWF for the northern and southern hemispheres. (Hollingsworth, 2004). Both figures demonstrate the current state of NWP forecasting...

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....

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

Toga Coare

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...

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

Anticyclone Images And Flowchart

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

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...

Cyclall

Atmospheric Science Letters

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...