# NASA Global Satellite and Model Data Products and Services for Tropical Meteorology and Climatology
## 4 Examples
### An MJO Event during October and November 2011  
The evolution, structure, and spatial variability of an MJO event has been studied by [PERSON] and [PERSON] [52] with data from the observations of the DYNAMO (the Dynamics of the Madden-Julian Oscillation) ship-borne radar and TRMM. In this example, several datasets during Phase 2 (20-29 October) in the area (60\({}^{\circ}\)-100\({}^{\circ}\) E and 15\({}^{\circ}\) N-S) were extracted from the data archive and plotted in Figures 3 and 4. Most variables have been averaged during 20-29 October to be consistent with the analysis in the study [52] and the others consist of accumulated rainfall and a snapshot of the merged IR brightness temperature.  
Figure 3: A Madden–Julian Oscillation event in October 2011. (**a**) Accumulated rainfall (in mm) from the half-hourly IMERG Final Run between 20 and 29 October 2011; (**b**) MERRA-2 average surface skin temperature (in Kelvin); and (**c**) a snapshot of the IR brightness temperature (in Kelvin) from the NOAA NCEP CPC merged IR dataset at 00Z 25 October 2011.  
Accumulated rainfall can be obtained with Giovanni. In Figure 3a, it was seen that over 1000 mm accumulated rainfall during the 10 day period was found in the study area. Compared to the 3B42 maximum rainfall (-300 mm) in Figure 2[52], the rainfall from the IMERG Final Run much exceeds that of 3B42 in this particular case. Over land, biases in the IMERG Final Run are largely corrected by gauge data from GPCC. By contrast, over oceans, due to the lack of gauge observations, biases are not corrected. Figure 3b shows the MERRA-2 surface skin temperature map averaged during the same period. It is seen that the surface skin temperatures in the heavy rainfall area and its north are high compared to the area in the south. A snapshot (generated with Panoply) of the brightness temperatures from the merged IR dataset is shown in Figure 3c, consisting of clusters of convective cells in different sizes. Animation files can be made from this high-temporal (30 min) and 4 km dataset to show the evolution of these cloud clusters (not shown).  
More dataset plots can be generated with Giovanni. Figure 4 shows the conditions at 850 hPa for the same Phase 2 MJO event, including wind, air temperature, geopotential height, and specific humidity. Strong westerly winds between 60\({}^{\circ}\) and 70\({}^{\circ}\) E near the Equator are surrounded by the easterly winds (Figure 4a) and the heavy accumulated rainfall area is found in the convergent area where both winds meet. Air temperatures are cooler in the rainy area than those in the surrounding areas (Figure 4b). A low geopotential height area is centered in the north of the strong westerly wind zone in Figure 4c and the anticlockwise flow pattern is visible in the wind vector map (Figure 4a) as well. Specific humidity is low in the strong westerly wind zone (Figure 4d), compared to the rest of the areas. Specific humidity is generally found high along the convergent area. All these are similar to what have been described in a typical MJO schematic diagram (i.e., [53]).