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horizon to few days at scales of 100 km ( Judt 2020 ). Third, small-scale physical processes such as cloud microphysics and radiation can relatively easily affect scales large enough to be of interest to predictions through their effects on the vertical profiles of latent (and radiative) heating and thus divergent wind. For example, convective invigoration by increased cloud condensation nuclei ( Rosenfeld et al. 2008 ) and larger or longer-lived anvils ( Fan et al. 2013 ) affect convective
horizon to few days at scales of 100 km ( Judt 2020 ). Third, small-scale physical processes such as cloud microphysics and radiation can relatively easily affect scales large enough to be of interest to predictions through their effects on the vertical profiles of latent (and radiative) heating and thus divergent wind. For example, convective invigoration by increased cloud condensation nuclei ( Rosenfeld et al. 2008 ) and larger or longer-lived anvils ( Fan et al. 2013 ) affect convective
. , 65 , 714 – 736 , https://doi.org/10.1175/2007JAS2488.1 . 10.1175/2007JAS2488.1 De Silva , V. , and J. B. Tenenbaum , 2004 : Sparse multidimensional scaling using landmark points. Tech. Rep., Stanford University, 41 pp . Doms , G. , and M. Schättler , 2002 : A description of the nonhydrostatic regional model LM. Part I: Dynamics and numerics. Deutscher Wetterdienst, 140 pp. , http://www.cosmo-model.org . Doms , G. , and Coauthors , 2011 : A description of the nonhydrostatic
. , 65 , 714 – 736 , https://doi.org/10.1175/2007JAS2488.1 . 10.1175/2007JAS2488.1 De Silva , V. , and J. B. Tenenbaum , 2004 : Sparse multidimensional scaling using landmark points. Tech. Rep., Stanford University, 41 pp . Doms , G. , and M. Schättler , 2002 : A description of the nonhydrostatic regional model LM. Part I: Dynamics and numerics. Deutscher Wetterdienst, 140 pp. , http://www.cosmo-model.org . Doms , G. , and Coauthors , 2011 : A description of the nonhydrostatic
respective effects can finally be assessed by comparison to S ENS . f. Weather regime dependence In regional atmospheric modeling, internal processes uncertainty preferentially affects precipitation during weak synoptic forcing episodes (e.g., Stensrud et al. 2000 ; Keil et al. 2014 ). The question here is, if the precipitation sensitivity to the uncertainty in the representation of terrestrial water flow also depends on the level of synoptic forcing. Keil et al. (2014) used the convective adjustment
respective effects can finally be assessed by comparison to S ENS . f. Weather regime dependence In regional atmospheric modeling, internal processes uncertainty preferentially affects precipitation during weak synoptic forcing episodes (e.g., Stensrud et al. 2000 ; Keil et al. 2014 ). The question here is, if the precipitation sensitivity to the uncertainty in the representation of terrestrial water flow also depends on the level of synoptic forcing. Keil et al. (2014) used the convective adjustment
Aerosol Effects on Clouds and Precipitation over Central Europe in Different Weather Regimes( Rosenfeld et al. 2008 ). The larger water load at the freezing level results in an additional release of latent heat, leading to an invigoration of convection with additional rainfall. Even in absence of such a thermodynamic invigoration, Fan et al. (2013) found that aerosol’s microphysical effects can lead to a dramatic increase in cloud cover, cloud-top height, and cloud thickness at the mature and dissipation stages by inducing larger amounts of smaller but longer-lasting ice particles in the
( Rosenfeld et al. 2008 ). The larger water load at the freezing level results in an additional release of latent heat, leading to an invigoration of convection with additional rainfall. Even in absence of such a thermodynamic invigoration, Fan et al. (2013) found that aerosol’s microphysical effects can lead to a dramatic increase in cloud cover, cloud-top height, and cloud thickness at the mature and dissipation stages by inducing larger amounts of smaller but longer-lasting ice particles in the
convection to determine if the anticipated physical effects are present. Based on these results, a revised version of the PSP scheme will be defined that has the potential to improve forecast skill for convective precipitation. To demonstrate improved skill will require a systematic evaluation of ensemble forecasts over a long test period. This will be the subject of a future study. The PSP scheme ( Kober and Craig 2016 ) aims to better couple subgrid turbulence to convective initiation by reintroducing
convection to determine if the anticipated physical effects are present. Based on these results, a revised version of the PSP scheme will be defined that has the potential to improve forecast skill for convective precipitation. To demonstrate improved skill will require a systematic evaluation of ensemble forecasts over a long test period. This will be the subject of a future study. The PSP scheme ( Kober and Craig 2016 ) aims to better couple subgrid turbulence to convective initiation by reintroducing
from the Integrated Global Radiosonde Archive (IGRA; Durre et al. 2006 ). Table 1. Geographical information on the five stations in Quang Ninh Province (cf. Fig. 1 ) from which hourly rainfall measurements are available. Five-digit station ID numbers indicate a surface synoptic observation (SYNOP) station and three-digit station IDs are regional station IDs. Fig . 2. Box-and-whisker plots of accumulated rainfall (mm) during 1200 UTC 25 Jul–1200 UTC 3 Aug. The availability of historical data is
from the Integrated Global Radiosonde Archive (IGRA; Durre et al. 2006 ). Table 1. Geographical information on the five stations in Quang Ninh Province (cf. Fig. 1 ) from which hourly rainfall measurements are available. Five-digit station ID numbers indicate a surface synoptic observation (SYNOP) station and three-digit station IDs are regional station IDs. Fig . 2. Box-and-whisker plots of accumulated rainfall (mm) during 1200 UTC 25 Jul–1200 UTC 3 Aug. The availability of historical data is
the forecast errors associated with these changes. For mature TCs that make landfall, on the other hand, many (idealized) studies document the influence of either a flat coastal region or an orographic barrier (e.g., Taiwan) on the track and structural development. When a TC vortex impinges on land, regardless of orography, it has two effects: a reduction of moisture supply and an increase of surface roughness. First, when the inner core is still over the ocean, dry air from land is transported
the forecast errors associated with these changes. For mature TCs that make landfall, on the other hand, many (idealized) studies document the influence of either a flat coastal region or an orographic barrier (e.g., Taiwan) on the track and structural development. When a TC vortex impinges on land, regardless of orography, it has two effects: a reduction of moisture supply and an increase of surface roughness. First, when the inner core is still over the ocean, dry air from land is transported
Atlantic THORPEX Regional Campaign (ATReC; Rabier et al. 2008 ), Winter Storm Reconnaissance (WSR, e.g., Szunyogh et al. 2000 ), the THORPEX Pacific Asian Regional Campaign (T-PARC, Weissmann et al. 2011 ), and the Convective and Orographically Induced Precipitation Study/European THORPEX Regional Campaign (COPS/ETReC 2007; Wulfmeyer et al. 2011 ), which all focused on the impact of additional observations on improving forecast accuracy. This idea was pioneered by the Fronts and Atlantic Storm
Atlantic THORPEX Regional Campaign (ATReC; Rabier et al. 2008 ), Winter Storm Reconnaissance (WSR, e.g., Szunyogh et al. 2000 ), the THORPEX Pacific Asian Regional Campaign (T-PARC, Weissmann et al. 2011 ), and the Convective and Orographically Induced Precipitation Study/European THORPEX Regional Campaign (COPS/ETReC 2007; Wulfmeyer et al. 2011 ), which all focused on the impact of additional observations on improving forecast accuracy. This idea was pioneered by the Fronts and Atlantic Storm
used in this study to assess intrinsic predictability limits without the need to resolve the convection explicitly. This approach is justified by the results of Selz and Craig (2015a) , who showed for a regional model that the stochastic convection scheme is able to generate similar synoptic-scale errors from upscale error growth at 60-h lead time as a convection-permitting simulation. The scheme explicitly models individual updrafts within a grid box, where the strength of each updraft (the cloud
used in this study to assess intrinsic predictability limits without the need to resolve the convection explicitly. This approach is justified by the results of Selz and Craig (2015a) , who showed for a regional model that the stochastic convection scheme is able to generate similar synoptic-scale errors from upscale error growth at 60-h lead time as a convection-permitting simulation. The scheme explicitly models individual updrafts within a grid box, where the strength of each updraft (the cloud
determine . A standard discrete Fourier transform (DFT) should not be used on the wind fields of a regional model because they are nonperiodic, which would lead to substantial aliasing from modes larger than the domain size. One option to deal with this problem is to apply a detrending of the fields first. The second, mathematically more elegant, option is to use a DCT that is not sensitive to nonperiodic boundaries, as is widely used in fields such as image processing and compression. A DCT is
determine . A standard discrete Fourier transform (DFT) should not be used on the wind fields of a regional model because they are nonperiodic, which would lead to substantial aliasing from modes larger than the domain size. One option to deal with this problem is to apply a detrending of the fields first. The second, mathematically more elegant, option is to use a DCT that is not sensitive to nonperiodic boundaries, as is widely used in fields such as image processing and compression. A DCT is
