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adjoint sensitivities to all elements of the initial state and the covariance relationship of this single element with all elements of the initial state. The use of ensemble sensitivity has expanded beyond its original derivation as a convenient tool or an intermediate step in quantifying the impact of targeted observations and it has later been used independently in many sensitivity studies ( Torn and Hakim 2008 ; Garcies and Homar 2009 ; Torn 2010 ; Chang et al. 2013 ; Hanley et al. 2013
adjoint sensitivities to all elements of the initial state and the covariance relationship of this single element with all elements of the initial state. The use of ensemble sensitivity has expanded beyond its original derivation as a convenient tool or an intermediate step in quantifying the impact of targeted observations and it has later been used independently in many sensitivity studies ( Torn and Hakim 2008 ; Garcies and Homar 2009 ; Torn 2010 ; Chang et al. 2013 ; Hanley et al. 2013
for this purpose, since these models are very expensive to run. Therefore in many studies, climate models of intermediate complexity are employed. Their short runtimes make the application of rigorous statistical methods possible, while they are still able to reproduce the mean climate characteristics on a global scale. Furthermore, due to the simplified nature of such models, model-independent climate system properties, such as the climate sensitivity, can be treated as explicit parameters, which
for this purpose, since these models are very expensive to run. Therefore in many studies, climate models of intermediate complexity are employed. Their short runtimes make the application of rigorous statistical methods possible, while they are still able to reproduce the mean climate characteristics on a global scale. Furthermore, due to the simplified nature of such models, model-independent climate system properties, such as the climate sensitivity, can be treated as explicit parameters, which
Basis, S. Solomon et al., Eds., Cambridge University Press, 499–588 . Diehl , K. , and S. Wurzler , 2004 : Heterogeneous drop freezing in the immersion mode: Model calculations considering soluble and insoluble particles in the drops. J. Atmos. Sci. , 61 , 2063 – 2072 . Diehl , K. , M. Simmel , and S. Wurzler , 2006 : Numerical sensitivity studies on the impact of aerosol properties and drop freezing modes on the glaciation, microphysics, and dynamics of clouds. J. Geophys. Res
Basis, S. Solomon et al., Eds., Cambridge University Press, 499–588 . Diehl , K. , and S. Wurzler , 2004 : Heterogeneous drop freezing in the immersion mode: Model calculations considering soluble and insoluble particles in the drops. J. Atmos. Sci. , 61 , 2063 – 2072 . Diehl , K. , M. Simmel , and S. Wurzler , 2006 : Numerical sensitivity studies on the impact of aerosol properties and drop freezing modes on the glaciation, microphysics, and dynamics of clouds. J. Geophys. Res
improved precipitation pattern. In a previous study, Miguez-Macho et al. (2004) had shown that SN also reduced the sensitivity of regional precipitation patterns to the choice of model domain and grid geometry, while maintaining the RCM-simulated small-scale structures. Meinke et al. (2006) showed a better agreement of simulated cloudiness with satellite-derived observations with SN. The study of Weisse and Feser (2003) demonstrated that intermittent divergence in phase space is strongly reduced
improved precipitation pattern. In a previous study, Miguez-Macho et al. (2004) had shown that SN also reduced the sensitivity of regional precipitation patterns to the choice of model domain and grid geometry, while maintaining the RCM-simulated small-scale structures. Meinke et al. (2006) showed a better agreement of simulated cloudiness with satellite-derived observations with SN. The study of Weisse and Feser (2003) demonstrated that intermittent divergence in phase space is strongly reduced
plausible that the validity of adjoint sensitivities decreases as resolution increases. Previous studies at about 100-km horizontal resolution have shown a good tangent linear approximation of the nonlinear model out to about 1.5 days ( Vukicevic 1991 ; Errico and Vukicevic 1992 ), and even less in regions of explosive cyclogenesis. Gilmour et al. (2001) has shown that the tangent linear approximation is usually valid less than a day, based on examining the ECMWF SV-based ensemble system run at T159L
plausible that the validity of adjoint sensitivities decreases as resolution increases. Previous studies at about 100-km horizontal resolution have shown a good tangent linear approximation of the nonlinear model out to about 1.5 days ( Vukicevic 1991 ; Errico and Vukicevic 1992 ), and even less in regions of explosive cyclogenesis. Gilmour et al. (2001) has shown that the tangent linear approximation is usually valid less than a day, based on examining the ECMWF SV-based ensemble system run at T159L
condensation contributes to changes in the maximum tangential velocity following a decrease in the central pressure field is an inadequate description of the time-dependent behavior. In this study, we perform a sensitivity analysis by using a cloud-permitting nonhydrostatic axisymmetric adjoint model to examine the role of sea surface fluctuations in determining the intensity of a mature-state hurricane. The adjoint-based analysis can trace the sensitivity of the response function backward in time, as is
condensation contributes to changes in the maximum tangential velocity following a decrease in the central pressure field is an inadequate description of the time-dependent behavior. In this study, we perform a sensitivity analysis by using a cloud-permitting nonhydrostatic axisymmetric adjoint model to examine the role of sea surface fluctuations in determining the intensity of a mature-state hurricane. The adjoint-based analysis can trace the sensitivity of the response function backward in time, as is
schematically illustrated in Fig. 4 . In this paper the observational aspects using conventional datasets and vertical cross sections from CloudSat , sensitivity using a mesoscale high-resolution Advanced Research Weather Research and Forecasting Model (ARW-WRF), and validation of this scenario are addressed. The goal of this study is to illustrate the major role of soil moisture, stratiform cloud, and divergent circulations for the motion of the onset isochrones from Kerala at 10°N to New Delhi near 25°N
schematically illustrated in Fig. 4 . In this paper the observational aspects using conventional datasets and vertical cross sections from CloudSat , sensitivity using a mesoscale high-resolution Advanced Research Weather Research and Forecasting Model (ARW-WRF), and validation of this scenario are addressed. The goal of this study is to illustrate the major role of soil moisture, stratiform cloud, and divergent circulations for the motion of the onset isochrones from Kerala at 10°N to New Delhi near 25°N
to analyze and present the response of binary image metrics to changes in the forecast situation. Section 2 presents the formulation of the binary distance measures analyzed in this work and includes a discussion of the properties a distance measure must satisfy in order to be classified as a metric. Section 3 details the synthetic forecast situation used to study the response of these distance measures to changes in base rate, bias, and displacement. In section 4 , three scenarios with
to analyze and present the response of binary image metrics to changes in the forecast situation. Section 2 presents the formulation of the binary distance measures analyzed in this work and includes a discussion of the properties a distance measure must satisfy in order to be classified as a metric. Section 3 details the synthetic forecast situation used to study the response of these distance measures to changes in base rate, bias, and displacement. In section 4 , three scenarios with
BEIS2), and may produce different BVOC emissions from BEIS2 ( Yin et al. 2004 ). However, the purpose of this study is to reveal the sensitivity of BVOC emissions and subsequent O 3 concentrations to different meteorological inputs that result from the RCM downscaling with different cumulus parameterizations. The use of BEIS2 is sufficient and is not expected to change our key conclusions. c. Regional Air-Quality Model The AQM is developed from the San Joaquin Valley Air Quality Study
BEIS2), and may produce different BVOC emissions from BEIS2 ( Yin et al. 2004 ). However, the purpose of this study is to reveal the sensitivity of BVOC emissions and subsequent O 3 concentrations to different meteorological inputs that result from the RCM downscaling with different cumulus parameterizations. The use of BEIS2 is sufficient and is not expected to change our key conclusions. c. Regional Air-Quality Model The AQM is developed from the San Joaquin Valley Air Quality Study
notable differences in the intensity forecast. Although most of the aforementioned sensitivity studies investigated the roles of physical parameterization schemes in the numerical simulations of hurricanes, it is still not clear how and why the physical parameterizations influence the simulated storm development because of the complex interactions among the physical processes in numerical models. In addition, little progress has been made in the understanding of the rapid intensification of hurricanes
notable differences in the intensity forecast. Although most of the aforementioned sensitivity studies investigated the roles of physical parameterization schemes in the numerical simulations of hurricanes, it is still not clear how and why the physical parameterizations influence the simulated storm development because of the complex interactions among the physical processes in numerical models. In addition, little progress has been made in the understanding of the rapid intensification of hurricanes
