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2003 ) in the region. Because of measurement limitations, this study was unable to characterize one of the most important aspects of the ISCCP regimes—their precipitation and hence, their latent heating behavior. The first aim of the present study is to better describe these regime characteristics using additional data. A recent data source for the study of tropical precipitation and tropical latent heating is the National Aeronautics and Space Administration (NASA) Tropical Rainfall Measuring
2003 ) in the region. Because of measurement limitations, this study was unable to characterize one of the most important aspects of the ISCCP regimes—their precipitation and hence, their latent heating behavior. The first aim of the present study is to better describe these regime characteristics using additional data. A recent data source for the study of tropical precipitation and tropical latent heating is the National Aeronautics and Space Administration (NASA) Tropical Rainfall Measuring
1. Introduction The release of latent heating (LH) during the formation of precipitation is of immense consequence to the nature of large- and small-scale atmospheric circulations, particularly in the tropics where various large-scale tropical modes controlled by LH persist and vary on a global scale. Latent heat release and its variations are without doubt the most important diabatic processes within the atmosphere, and thus play a central role in the earth’s water cycle. Latent heating is
1. Introduction The release of latent heating (LH) during the formation of precipitation is of immense consequence to the nature of large- and small-scale atmospheric circulations, particularly in the tropics where various large-scale tropical modes controlled by LH persist and vary on a global scale. Latent heat release and its variations are without doubt the most important diabatic processes within the atmosphere, and thus play a central role in the earth’s water cycle. Latent heating is
1. Introduction Latent heat released during moist convective processes can trigger a slew of local and large-scale phenomena. Local changes such as buoyancy perturbations manifest themselves as gravity waves that can engender further convection leading to mesoscale organization ( Mapes 1993 ; Lac and Lafore 2002 ). The condensational heating from organized convective systems can determine the seasonal and intraseasonal sources of tropical variability, as demonstrated by idealized modeling
1. Introduction Latent heat released during moist convective processes can trigger a slew of local and large-scale phenomena. Local changes such as buoyancy perturbations manifest themselves as gravity waves that can engender further convection leading to mesoscale organization ( Mapes 1993 ; Lac and Lafore 2002 ). The condensational heating from organized convective systems can determine the seasonal and intraseasonal sources of tropical variability, as demonstrated by idealized modeling
1. Introduction Latent heating (LH) is a major driver of atmospheric circulation in the tropics and extratropics ( Webster 1972 ; Hartmann et al. 1984 ; Schumacher et al. 2004 ; Hagos and Zhang 2010 ). LH in precipitating systems is also associated with vertical energy transport throughout the troposphere ( Houze 1982 ). A number of studies have shown that the dynamical response of the atmospheric circulation to heating is sensitive to the vertical and horizontal distribution of LH ( Anthes
1. Introduction Latent heating (LH) is a major driver of atmospheric circulation in the tropics and extratropics ( Webster 1972 ; Hartmann et al. 1984 ; Schumacher et al. 2004 ; Hagos and Zhang 2010 ). LH in precipitating systems is also associated with vertical energy transport throughout the troposphere ( Houze 1982 ). A number of studies have shown that the dynamical response of the atmospheric circulation to heating is sensitive to the vertical and horizontal distribution of LH ( Anthes
moistening by shallow boundary layer and congestus are necessary to realistically produce the wide range of tropical temporal and spatial variability, including MJO ( Khouider and Majda 2007 ). Modeling studies have shown that warm-rain processes may play an important role in regulating the time scales of MJO convective cycles through dynamical feedback induced by cloud radiation and latent heating ( Lee et al. 2001 ; Lin and Mapes 2004 ; Lau et al. 2005 ). Using a community climate model, Zhang and
moistening by shallow boundary layer and congestus are necessary to realistically produce the wide range of tropical temporal and spatial variability, including MJO ( Khouider and Majda 2007 ). Modeling studies have shown that warm-rain processes may play an important role in regulating the time scales of MJO convective cycles through dynamical feedback induced by cloud radiation and latent heating ( Lee et al. 2001 ; Lin and Mapes 2004 ; Lau et al. 2005 ). Using a community climate model, Zhang and
simulations by simple as well as complex numerical models. For example, Chang (1977) showed that the phase speed of the equatorial Kelvin wave is reduced when friction is explicitly included in the linear wave theory ( Matsuno 1966 ). According to such linear theory of the equatorial waves, the phase speed c of the Kelvin wave is directly related to the equivalent depth h as c = ( gh ) 1/2 . It was pointed out that if tropical diabatic heating, mainly convective latent heating, had its peak in the
simulations by simple as well as complex numerical models. For example, Chang (1977) showed that the phase speed of the equatorial Kelvin wave is reduced when friction is explicitly included in the linear wave theory ( Matsuno 1966 ). According to such linear theory of the equatorial waves, the phase speed c of the Kelvin wave is directly related to the equivalent depth h as c = ( gh ) 1/2 . It was pointed out that if tropical diabatic heating, mainly convective latent heating, had its peak in the
studies is its large-scale character that is conducive for upward development of cyclonic circulation well above the midtroposphere. In fact, this feature can be noticed during active monsoons as evidenced from the reanalysis circulation data (see Fig. 4 ). The specific question addressed here is the role of latent heating distribution on the vertical development of the continental-scale circulation response above the midtropospheric levels over the MT region. Simple models based on the first
studies is its large-scale character that is conducive for upward development of cyclonic circulation well above the midtroposphere. In fact, this feature can be noticed during active monsoons as evidenced from the reanalysis circulation data (see Fig. 4 ). The specific question addressed here is the role of latent heating distribution on the vertical development of the continental-scale circulation response above the midtropospheric levels over the MT region. Simple models based on the first
Rossby wave activity arise from nonconservative processes (i.e., diabatic heating and friction). The excitation of Rossby waves is expected to be overwhelmingly due to diabatic heating (friction being primarily a sink and not a source of Rossby wave activity), which is dominated by latent heat release via convective heating and/or large-scale condensational heating. Sources of in situ (local to the Arctic) latent heat release in the atmosphere can occur through many different processes, such as 1) an
Rossby wave activity arise from nonconservative processes (i.e., diabatic heating and friction). The excitation of Rossby waves is expected to be overwhelmingly due to diabatic heating (friction being primarily a sink and not a source of Rossby wave activity), which is dominated by latent heat release via convective heating and/or large-scale condensational heating. Sources of in situ (local to the Arctic) latent heat release in the atmosphere can occur through many different processes, such as 1) an
during field campaigns provided little evidence of undiluted convective cores ( LeMone and Zipser 1980 ; Zipser and LeMone 1980 ; Igau et al. 1999 ; Anderson et al. 2005 ; and others). Based on observations of updraft intensities, Zipser (2003) demonstrated that parcels likely require additional buoyancy provided by latent heating above the freezing level in order to reach the upper troposphere. To provide further evidence for the claims in Zipser (2003) , Fierro et al. (2009) performed a
during field campaigns provided little evidence of undiluted convective cores ( LeMone and Zipser 1980 ; Zipser and LeMone 1980 ; Igau et al. 1999 ; Anderson et al. 2005 ; and others). Based on observations of updraft intensities, Zipser (2003) demonstrated that parcels likely require additional buoyancy provided by latent heating above the freezing level in order to reach the upper troposphere. To provide further evidence for the claims in Zipser (2003) , Fierro et al. (2009) performed a
1. Introduction The global distribution of precipitation is related to water circulation in the climate system and to latent heating (LH) in the atmosphere, which is an important heat source driving atmospheric circulation ( Nigam et al. 2000 ). Characteristics of precipitation change greatly over a wide spectrum according to precipitation type and surface and atmospheric conditions. Satellite observations of clouds have provided useful but indirect information on precipitation. Precipitation
1. Introduction The global distribution of precipitation is related to water circulation in the climate system and to latent heating (LH) in the atmosphere, which is an important heat source driving atmospheric circulation ( Nigam et al. 2000 ). Characteristics of precipitation change greatly over a wide spectrum according to precipitation type and surface and atmospheric conditions. Satellite observations of clouds have provided useful but indirect information on precipitation. Precipitation