Search Results

You are looking at 111 - 120 of 23,543 items for :

  • Cloud forcing x
  • All content x
Clear All
Seoung Soo Lee

not on interactions between clouds and large scales much larger than the model domain where clouds are generated in this study. Hence, observed heat and moisture fluxes are imposed on the model surface and there are no two-way interactions between surface fluxes and clouds. To prevent the reflection of gravity or sound waves from the model top, a damping layer of 5-km depth is applied near the model top. The TWP-ICE observations provide initial humidity, temperature, and large-scale forcings of

Full access
Peter Siegmund

DECEMBER 1993 S I EG M U N D 2419Cloud Diabatic Forcing of the Atmosphere, Estimated from Simultaneous ECMWF Diabatic Heating and ISCCP Cloud Amount Observations PETER SIEGMUNDRoyal Netherlands Meteorological Institute, De Bilt, the Netherlands(Manuscript received 21 August 1992, in final form 3 May 1993) ABSTRACT The cloud diabafic forcing (CDF) of the

Full access
Patrick C. Taylor

Salby 1997 ). These studies demonstrate the importance of cloud to the TOA flux diurnal cycle; however, few studies analyze the diurnal cycle of longwave cloud forcing (LWCF). The diurnal cycle of the cloud radiative impacts on the OLR diurnal cycle can be quantified using LWCF. LWCF is defined as the difference between OLR and clear-sky OLR (OLR CLR ), as shown: Nowicki and Merchant (2004) use LWCF and shortwave cloud forcing (SWCF) determined from GERB to elucidate the radiative impact of the

Full access
Michael S. Town, Von P. Walden, and Stephen G. Warren

radiative forcing (LDCRF). Acronyms used in this paper are given in Tables 1 and 2 . 2. Instrumentation and data The data used in this study come from several sources: (a) the South Pole Atmospheric Radiation and Cloud Lidar Experiment (SPARCLE), performed from January to October 2001 ( Walden et al. 2001 ); (b) a field experiment performed at the South Pole in 1992 ( Walden 1995 ; Walden et al. 1998 ); (c) routine measurements of temperature and atmospheric composition made by the Climate

Full access
Hervé Le Treut, Michèle Forichon, Olivier Boucher, and Zhao-Xin Li

have very different effects: the CO 2 content or the sulfate aerosol loading. Whereas the CO 2 increase represents a positive climate forcing, inducing a warming, the increased aerosol concentration may have resulted in a negative climate forcing, by increasing reflection of solar radiation, both directly and indirectly through a modification of cloud properties. This effect is not only opposite to the greenhouse warming effect in sign, but also in nature, because it acts on the shortwave

Full access
Jayesh Phadtare and G. S. Bhat

of strong and weak synoptic forcing compare? Addressing this question is the main objective of the paper. We also examine the dependence of preferred locations and timings of MCS triggering in relation to the synoptic forcing field. The paper is organized as follows. Study area, data, and method are described in section 2 . Section 3 presents some case studies of evolution of deep convective clouds in the presence of synoptic forcing. Section 4 presents characteristics of deep clouds with

Free access
Markus Stowasser and Kevin Hamilton

integrations varied by a factor of as much as 3 among the models. Much of the variation in the climate sensitivity of the global-mean surface temperature is attributable to differences in how the clouds respond to climate forcing (e.g., Senior 1999 ; Yao and Del Genio 1999 ). Cess et al. (1996) showed that there was considerable variability in both the shortwave and longwave cloud feedbacks in global warming simulations performed with a large number of different global models. In a recent study

Full access
Yizhe Peggy Bu, Robert G. Fovell, and Kristen L. Corbosiero

10 m above mean sea level (MSL) is used to define the storm size or width. Bu et al. (2014) demonstrated that cloud-radiative forcing (CRF), the interaction of hydrometeors with longwave and shortwave radiation, has an important role in expanding the storm size. Averaged through a diurnal cycle, CRF consists of pronounced cooling along the anvil top and weak warming through the cloudy air. In particular, the within-cloud warming was relevant, enhancing convective activity in the TC outer core

Full access
H. Le Treut, Z. X. Li, and M. Forichon

DECEMBER 1994 LE TREUT ET AL. 1827Sensitivity of the LMD General Circulation Model to Greenhouse Forcing Associated with Two Different Cloud Water ParameterizationsH. LE TREUT, Z. X. LI, AND M. FORICHONLaboratoire de M~tdorologie Dynamique du CNRS, Paris, France(Manuscript received 14 July 1993, in final form 2 May 1994) ABSTRACT The atmospheric general

Full access
C. P. Weaver

.g., Gleckler et al. 1995 ; Kiehl et al. 1995 ) and also are responsible for large uncertainties in the response of models to climate forcing ( Cess et al. 1990 , 1996 ; Lee et al. 1997 ). Thus, focused research into clouds and climate remains a necessity. The goal of this study is to extend our understanding of controls on cloud radiative forcing (CRF) over extratropical oceans. Specifically, this paper examines how the movement of cyclones in the North Atlantic summertime storm track influences the

Full access