TC genesis in a high-resolution global storm resolving model

Identifing factors that influence convective organization and their relation to tropical cyclone genesis in simulations using a new generation of earth system models

 

The aim of this project is to identify the main factors influencing convective organization in and around the Atlantic ITCZ and the East Pacific in a high-resolution global storm resolving simulation. Here the focus is on the high resolution (2.5 km grid spacing) ICON simulation from the DWD and MPI-M. This simulation runs for 40 days with initial conditions supplied by the ECMWF operational analysis at 01 Aug 2016. During this period a total of 4 cyclones can be identified in the North Atlantic, with only one originating at a latitude below 30 deg N. There are a total of 7 identified in the East Pacific. Below are links to analyses of these individual systems. Later a comparison will be offered to non-developing systems in the same data set.

 

Figure 1. Maximum 10 meter speed (within a 2 deg box centrerd on the storm) for all systems analysed in the North Atlantic and in the East Pacific. Two black horizontal lines indicate the required wind seepd for tropical storm and hurricane classification.

 

 

Figure 2. Initial SSTs all systems analysed in the North Atlantic and in the East Pacific. The yellow contour encompasses regions with SSTs higher than 27 deg, the value often seen as the minimum SST required for genesis to occur.

 

 

1. North Atlantic

 

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Figure 3. Tracks of all cyclones identified over the North Atlantic in the 40 day ICON 2.5 km global simulation. The four cyclones analysed are as follows: TC1 (yellow curve), TC2 (green curve), TC3 (aqua curve) and TC4 (pink curve). Shown also is a snapshot of the MSLP at the time shown. For further times, see the link to the animation below. Values of shading are given on the colour bar on the right.

 

Here is an animation of the 15 min MSLP fields for the North Atlantic with the tracks drawn as the TCs develop. Note that after the first TC decays there is an almost 25 day period of no cyclone activity in the tropics.

 

Full analysis of all TCs here - 

TC1 Analysis HERE
System 2 (Probably not very TC like - ignored)
TC3 Analysis HERE
System 4 (Probably not very TC like - ignored)

 

 

2. East Pacific

 

Figure 4. Tracks of all cyclones identified over the East Pacific in the 40 day ICON 2.5 km global simulation. The cyclones analysed are as follows: TC1 (yellow curve), TC2 (magenta curve), TC3 (green curve), TC4 (aqua curve), TC5 (black curve), TC6 (light blue curve) and TC7 (dark blue curve). Shown also is a snapshot of the MSLP at the time shown. For further times, see the link to the animation below. Values of shading are given on the colour bar on the right.

 

Here is an animation of the 15 min MSLP fields for the North Atlantic with the tracks drawn as the TCs develop.

Movie - East Pacific MSLP with TC tracking - 100 Mb avi

 

Full analysis of all TCs here - 

System 1 - Analysis here 
System 2
System 3
System 4
System 5
System 6
System 7