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1. Introduction Peninsular Florida (PF) sits on the border of the tropics and the extratropics, which makes for its unique geography in the continental United States. Thus, small shifts in the distinct circulation patterns and the thermodynamics of the tropics and extratropics tend to have a profound impact on PF ( Selman et al. 2013 ; Kirtman et al. 2017 ). In addition, the robust ocean circulations around PF ( Misra and Mishra 2016 ; Misra et al. 2017a ) are known to affect the hydroclimate
1. Introduction Peninsular Florida (PF) sits on the border of the tropics and the extratropics, which makes for its unique geography in the continental United States. Thus, small shifts in the distinct circulation patterns and the thermodynamics of the tropics and extratropics tend to have a profound impact on PF ( Selman et al. 2013 ; Kirtman et al. 2017 ). In addition, the robust ocean circulations around PF ( Misra and Mishra 2016 ; Misra et al. 2017a ) are known to affect the hydroclimate
was favored by warm SST and the vortex growth within the ER wave that spun off from the ITCZ. Fig . 6. The 30-km grid resolution ECMWF ERA5 reanalysis of TCW superimposed by 500- and 850-hPa wind vectors over Australia as well as the Pacific and Indian Oceans during the TC Kelvin (top) at 2000 UTC 17 Feb and (bottom) at 1100 UTC 19 Feb, respectively. Fig . 7. As in Fig. 6 , but for mean vertically integrated moisture divergence superimposed by 500-hPa wind vectors. Figure 8 shows time series of
was favored by warm SST and the vortex growth within the ER wave that spun off from the ITCZ. Fig . 6. The 30-km grid resolution ECMWF ERA5 reanalysis of TCW superimposed by 500- and 850-hPa wind vectors over Australia as well as the Pacific and Indian Oceans during the TC Kelvin (top) at 2000 UTC 17 Feb and (bottom) at 1100 UTC 19 Feb, respectively. Fig . 7. As in Fig. 6 , but for mean vertically integrated moisture divergence superimposed by 500-hPa wind vectors. Figure 8 shows time series of
rainfall extremes; accumulated precipitation is highly dependent on precipitation frequency (95%), while extremes are related to rainfall intensity ( Li et al. 2016 ). Trenberth et al. (2017) concluded that the observed precipitation events usually persisted for 12–15 h over the oceans in the tropics and subtropics, while precipitation lasted 20 h from the Community Earth System Model (CESM). Climate models could provide continuous spatiotemporal hourly precipitation data for investigating its
rainfall extremes; accumulated precipitation is highly dependent on precipitation frequency (95%), while extremes are related to rainfall intensity ( Li et al. 2016 ). Trenberth et al. (2017) concluded that the observed precipitation events usually persisted for 12–15 h over the oceans in the tropics and subtropics, while precipitation lasted 20 h from the Community Earth System Model (CESM). Climate models could provide continuous spatiotemporal hourly precipitation data for investigating its
decay of mesoscale convective systems and gravity waves ( Wang et al. 2007 ; Kikuchi and Wang 2008 ; Vondou et al. 2010 ). This complexity of the diurnal cycle over land means that, while the mechanisms of the diurnal cycle over land are well understood, the model performs better over the ocean areas. All comparisons in this study of ECMWF model performance were made relative to the TRMM TMPA and TRMM PR products. Despite the TMPA generally performing well ( Dai et al. 2007 ; Sapiano and Arkin
decay of mesoscale convective systems and gravity waves ( Wang et al. 2007 ; Kikuchi and Wang 2008 ; Vondou et al. 2010 ). This complexity of the diurnal cycle over land means that, while the mechanisms of the diurnal cycle over land are well understood, the model performs better over the ocean areas. All comparisons in this study of ECMWF model performance were made relative to the TRMM TMPA and TRMM PR products. Despite the TMPA generally performing well ( Dai et al. 2007 ; Sapiano and Arkin
.9° × 1.25°). The FHIST component set was used in CESM. CESM is composed of several Earth system component models: ocean, land, atmosphere, sea ice, land ice, river, and ocean wave. There are many defined component sets available to CESM users; each determines the active component(s) for a given model run. Component sets beginning with “F” have active land and atmosphere components while all other components are inactive or prescribed. “HIST” component sets use transient forcing valid for
.9° × 1.25°). The FHIST component set was used in CESM. CESM is composed of several Earth system component models: ocean, land, atmosphere, sea ice, land ice, river, and ocean wave. There are many defined component sets available to CESM users; each determines the active component(s) for a given model run. Component sets beginning with “F” have active land and atmosphere components while all other components are inactive or prescribed. “HIST” component sets use transient forcing valid for
States and many other regions around the world ( Redmond and Koch 1991 ; Dettinger et al. 1998 ). Through their impacts on convection and diabatic heating, SST anomalies in the tropical Pacific Ocean induce Rossby waves that result in the Pacific–North American (PNA) teleconnection ( Barnston and Livezey 1987 ). The PNA pattern influences precipitation and temperature in the western United States on a seasonal-to-interannual time scale. On interannual-to-decadal time scale, SST anomalies associated
States and many other regions around the world ( Redmond and Koch 1991 ; Dettinger et al. 1998 ). Through their impacts on convection and diabatic heating, SST anomalies in the tropical Pacific Ocean induce Rossby waves that result in the Pacific–North American (PNA) teleconnection ( Barnston and Livezey 1987 ). The PNA pattern influences precipitation and temperature in the western United States on a seasonal-to-interannual time scale. On interannual-to-decadal time scale, SST anomalies associated
tropical wave on 29 August 1962. Despite a long history of heavy rainfall, Louisiana experienced an event on 10–14 August 2016 that set numerous meteorological and hydrologic records ( Table 1 ). The storm produced a measured 48-h rainfall accumulation of 797.3 mm (31.39 in.; Fig. 1 ), the greatest 48-h recorded rainfall in Louisiana, surpassing the previous 2-day state record of 739.65 mm (29.12 in.) by 57.7 mm (2.27 in.). The storm also produced a record flood stage of 14.08 m (46.2 ft) on the Amite
tropical wave on 29 August 1962. Despite a long history of heavy rainfall, Louisiana experienced an event on 10–14 August 2016 that set numerous meteorological and hydrologic records ( Table 1 ). The storm produced a measured 48-h rainfall accumulation of 797.3 mm (31.39 in.; Fig. 1 ), the greatest 48-h recorded rainfall in Louisiana, surpassing the previous 2-day state record of 739.65 mm (29.12 in.) by 57.7 mm (2.27 in.). The storm also produced a record flood stage of 14.08 m (46.2 ft) on the Amite
with extensive flood loss and damage from exceptionally wet seasons. During the “long rains” season of 2018 flooding across Kenya caused the displacement of 300 000 people ( OCHA 2018 ), shortly followed by the “short rains” October–December season flooding of 2019, associated with a strong Indian Ocean dipole event ( Doi et al. 2020 ; Wainwright et al. 2020 ). Anomalous wet conditions persisted across East Africa through to May 2020 resulting in hundreds of deaths from flood and landslides and
with extensive flood loss and damage from exceptionally wet seasons. During the “long rains” season of 2018 flooding across Kenya caused the displacement of 300 000 people ( OCHA 2018 ), shortly followed by the “short rains” October–December season flooding of 2019, associated with a strong Indian Ocean dipole event ( Doi et al. 2020 ; Wainwright et al. 2020 ). Anomalous wet conditions persisted across East Africa through to May 2020 resulting in hundreds of deaths from flood and landslides and
extreme precipitation events, the anomalously low pressure in the Gulf of Alaska extends vertically into the middle troposphere, which is not necessarily the case for all ARs. A jet streak at 250 hPa is also located directly over the region during extreme precipitation events, as opposed to southwest, over the Pacific Ocean. Despite not being discussed here, Rossby wave breaking is an important mechanism for AR-induced extreme precipitation events ( Ryoo et al. 2013 ; Payne and Magnusdottir 2014
extreme precipitation events, the anomalously low pressure in the Gulf of Alaska extends vertically into the middle troposphere, which is not necessarily the case for all ARs. A jet streak at 250 hPa is also located directly over the region during extreme precipitation events, as opposed to southwest, over the Pacific Ocean. Despite not being discussed here, Rossby wave breaking is an important mechanism for AR-induced extreme precipitation events ( Ryoo et al. 2013 ; Payne and Magnusdottir 2014
) grid support in CAM allows for high-resolution grid spacing over an area of interest, in this case the North Atlantic basin, and does not require nearly as much computational resources as traditional global models run at high resolutions since the high resolution is not required over the entire globe ( Zarzycki et al. 2014 , 2015 ). Since TCs are localized to certain ocean basins and their representation in models is dependent on grid spacing, they are ideal phenomena to study with VR. In CAM
) grid support in CAM allows for high-resolution grid spacing over an area of interest, in this case the North Atlantic basin, and does not require nearly as much computational resources as traditional global models run at high resolutions since the high resolution is not required over the entire globe ( Zarzycki et al. 2014 , 2015 ). Since TCs are localized to certain ocean basins and their representation in models is dependent on grid spacing, they are ideal phenomena to study with VR. In CAM
