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hindcast simulation forced by the NCEP–NCAR wind forcing during 2000–11 is used to form the mean velocity. The Global Ocean Forecasting System (GOFS) 3.1 operated by the Center for Ocean–Atmosphere Predictions Studies of Florida State University employs the Hybrid Coordinate Ocean Model (HYCOM) forced by the Navy Global Environmental Model (NAVGEM) atmospheric forcing and the U.S. Navy Coupled Ocean Data Assimilation system ( Cummings 2005 ; Chassignet et al. 2009 ), with a horizontal resolution of 0
hindcast simulation forced by the NCEP–NCAR wind forcing during 2000–11 is used to form the mean velocity. The Global Ocean Forecasting System (GOFS) 3.1 operated by the Center for Ocean–Atmosphere Predictions Studies of Florida State University employs the Hybrid Coordinate Ocean Model (HYCOM) forced by the Navy Global Environmental Model (NAVGEM) atmospheric forcing and the U.S. Navy Coupled Ocean Data Assimilation system ( Cummings 2005 ; Chassignet et al. 2009 ), with a horizontal resolution of 0
layer salinity in the southeastern tropical Indian Ocean is influenced by the annual cycles of the ITF and the Leeuwin Current transports, air–sea freshwater forcing, and eddy fluxes ( Zhang et al. 2016 ). Strong salinity fronts observed within the equatorial region show meridional migration associated with the intertropical convergence zone and meridional ocean currents, which may be modulated interannually by zonal advections of less saline waters from the eastern Indian Ocean related to the ITF
layer salinity in the southeastern tropical Indian Ocean is influenced by the annual cycles of the ITF and the Leeuwin Current transports, air–sea freshwater forcing, and eddy fluxes ( Zhang et al. 2016 ). Strong salinity fronts observed within the equatorial region show meridional migration associated with the intertropical convergence zone and meridional ocean currents, which may be modulated interannually by zonal advections of less saline waters from the eastern Indian Ocean related to the ITF
Zealand downstream. Hence the change in local winds also force some modifications in surface fluxes and wind stress. Any link between ENSO-related variations in the ITF and the Tasman Sea heat waves has been generally assigned to the atmospheric bridge connections. The studies thus far have overlooked the likelihood that there is also a direct ocean connection through the changes in mass and heat transport with the ITF that indeed relate to opposite changes in the East Australian Current region
Zealand downstream. Hence the change in local winds also force some modifications in surface fluxes and wind stress. Any link between ENSO-related variations in the ITF and the Tasman Sea heat waves has been generally assigned to the atmospheric bridge connections. The studies thus far have overlooked the likelihood that there is also a direct ocean connection through the changes in mass and heat transport with the ITF that indeed relate to opposite changes in the East Australian Current region
the Tropical Rainfall Measuring Mission (TRMM; Huffman et al. 2007 ), which provides a continuous rainfall dataset covering the period from 1998 onward and allows direct study on the rainfall impacts of CSs and MJO that provide forcing from outside of the region. The quasistationary Borneo vortex that was studied by Chang et al. (2005a) is a local system that interacts with both cold surges and MJO and always has strong effects on rainfall. Its explicit impacts will be left to future study
the Tropical Rainfall Measuring Mission (TRMM; Huffman et al. 2007 ), which provides a continuous rainfall dataset covering the period from 1998 onward and allows direct study on the rainfall impacts of CSs and MJO that provide forcing from outside of the region. The quasistationary Borneo vortex that was studied by Chang et al. (2005a) is a local system that interacts with both cold surges and MJO and always has strong effects on rainfall. Its explicit impacts will be left to future study
tend to reduce diurnal fluctuations in surface temperature, a main direct diurnal forcing for land convection. Peatman et al. (2014) pointed out a “vanguard of precipitation” that increases over land more than over the sea of the MC immediately prior to the arrival of the large-scale convective envelope of the canonical MJO that propagates through the MC. This vanguard of precipitation is more pronounced for MJO-C than MJO-B ( Fig. 13 ). Land precipitation of MJO-C is slightly stronger than that
tend to reduce diurnal fluctuations in surface temperature, a main direct diurnal forcing for land convection. Peatman et al. (2014) pointed out a “vanguard of precipitation” that increases over land more than over the sea of the MC immediately prior to the arrival of the large-scale convective envelope of the canonical MJO that propagates through the MC. This vanguard of precipitation is more pronounced for MJO-C than MJO-B ( Fig. 13 ). Land precipitation of MJO-C is slightly stronger than that
region strengthen or weaken the surface winds, which reduce or enhance the latent heat flux (LHF) at the ocean surface. Further, variations in solar shortwave radiation flux (SWF) at the surface associated with MJO-related changes in cloudiness also occur. The combination of these flux variations can induce SST anomalies to the east and west of the convective region. The zonal SST gradient causes zonal changes in surface moist static energy and provides surface forcing, which induces the convection
region strengthen or weaken the surface winds, which reduce or enhance the latent heat flux (LHF) at the ocean surface. Further, variations in solar shortwave radiation flux (SWF) at the surface associated with MJO-related changes in cloudiness also occur. The combination of these flux variations can induce SST anomalies to the east and west of the convective region. The zonal SST gradient causes zonal changes in surface moist static energy and provides surface forcing, which induces the convection
condition, such as a “fish-bone” deforestation pattern, can induce mesoscale atmospheric circulation under weak synoptic-scale forcing that can enhance cloudiness and rainfall ( Wang et al. 2009 ; Negri et al. 2004 ; Roy 2009 ). A regional climate modeling study revealed an increase in precipitation at the edge of the forest in the Amazon basin due to an enhancement of prevailing wind resulting from an increased land–sea heat contrast after deforestation ( Ramos da Silva et al. 2008 ). Observational
condition, such as a “fish-bone” deforestation pattern, can induce mesoscale atmospheric circulation under weak synoptic-scale forcing that can enhance cloudiness and rainfall ( Wang et al. 2009 ; Negri et al. 2004 ; Roy 2009 ). A regional climate modeling study revealed an increase in precipitation at the edge of the forest in the Amazon basin due to an enhancement of prevailing wind resulting from an increased land–sea heat contrast after deforestation ( Ramos da Silva et al. 2008 ). Observational
events in the western United States related to tropical forcing . J. Climate , 13 , 793 – 820 , https://doi.org/10.1175/1520-0442(2000)013<0793:EPEITW>2.0.CO;2 . 10.1175/1520-0442(2000)013<0793:EPEITW>2.0.CO;2 Holloway , C. E. , and J. D. Neelin , 2009 : Moisture vertical structure, column water vapor, and tropical deep convection . J. Atmos. Sci. , 66 , 1665 – 1683 , https://doi.org/10.1175/2008JAS2806.1 . 10.1175/2008JAS2806.1 Holloway , C. E. , and J. D. Neelin , 2010
events in the western United States related to tropical forcing . J. Climate , 13 , 793 – 820 , https://doi.org/10.1175/1520-0442(2000)013<0793:EPEITW>2.0.CO;2 . 10.1175/1520-0442(2000)013<0793:EPEITW>2.0.CO;2 Holloway , C. E. , and J. D. Neelin , 2009 : Moisture vertical structure, column water vapor, and tropical deep convection . J. Atmos. Sci. , 66 , 1665 – 1683 , https://doi.org/10.1175/2008JAS2806.1 . 10.1175/2008JAS2806.1 Holloway , C. E. , and J. D. Neelin , 2010
resolution of circa 0.3° by 0.3°. These high-resolution forcing data allowed us to design a novel approach to quantify the role of the model spatial resolution by running WRF at multiple resolutions over a single domain in separate experiments (no nesting), all directly driven by ERA5 at their boundaries. This results in a comparable set of simulations at resolutions of 32, 16, 8, 4, and 2 km that run independently from each other and are identical in all other configuration parameters. The approach
resolution of circa 0.3° by 0.3°. These high-resolution forcing data allowed us to design a novel approach to quantify the role of the model spatial resolution by running WRF at multiple resolutions over a single domain in separate experiments (no nesting), all directly driven by ERA5 at their boundaries. This results in a comparable set of simulations at resolutions of 32, 16, 8, 4, and 2 km that run independently from each other and are identical in all other configuration parameters. The approach
removing the Coriolis force entirely. Figure 17 provides Hovmöller diagrams that show how the surface winds perpendicular to the coast in the nondimensional solution of Qian et al. (2009) evolve with time for various values of the nondimensional background wind . When the perturbations are largely symmetric, and propagate away from the coast in both directions. As the background wind increases, the perturbations on the downwind side of the coast initially become more erratic, and then increase in
removing the Coriolis force entirely. Figure 17 provides Hovmöller diagrams that show how the surface winds perpendicular to the coast in the nondimensional solution of Qian et al. (2009) evolve with time for various values of the nondimensional background wind . When the perturbations are largely symmetric, and propagate away from the coast in both directions. As the background wind increases, the perturbations on the downwind side of the coast initially become more erratic, and then increase in
