# NASA Global Satellite and Model Data Products and Services for Tropical Meteorology and Climatology
## 2 Satellite Missions, Projects and Data
### Trmm  
Launched in November 1997, TRMM is a NASA-JAXA (the Japan Aerospace Exploration Agency) research satellite mission [10; 11; 12; 13; 14] to better understand processes in tropical meteorology and climatology. TRMM provides observational data with footprints between 40\({}^{\circ}\) N-S. The first space-borne Ku-band precipitation radar on TRMM provides 4-dimensional datasets of rainfall and latent heating over vast tropical oceans and remote continents, which are extremely valuable (over 17 years of observations) not only for individual weather event case studies but also for tropical climatology, especially in conjunction with other ancillary datasets or observations [24]. TRMM has helped researchers better understand tropical rainfall properties and variation [24] including (1) rainfall intensity and spatial distribution; (2) partition of rainfall categories (from stratiform and convective clouds); (3) vertical distribution or profiles of hydrometeors; (4) diurnal and seasonal variation of rainfall amount and intensity; (5) lightning distribution and variation; and (6) 4-dimensional latent heating profiles.  
Table 1 lists precipitation and lightning instruments onboard TRMM, including the Visible and Infrared Scanner (VIRS), the TRMM Microwave Imager (TMI), the Precipitation Radar (PR) and the Lightning Imaging Sensor (LIS). Datasets from VIRS, TMI and PR are archived at GES DISC. The lightning datasets from LIS are hosted by the Global Hydrology Resource Center (GHRC) [25].  
With more datasets included from additional infrared and passive microwave sensors on other domestic and international satellites to increase both spatial and temporal samplings, algorithms have thus been developed and integrated for multi-sensor, multi-algorithm, and multi-satellite precipitation products such as, the TRMM Multi-Satellite Precipitation Analysis (TMPA) [26; 27]. Over the years, the TMPA datasets, consisting of 3-hourly, daily and monthly in both near-real-time and research-grade, have been widely used in tropical meteorology and climatology as well as in other disciplines such as diseases and food security [24].  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Description**} \\ \cline{2-6}
**Instrument Name** & \multicolumn{2}{c}{**Band**} & \multicolumn{2}{c}{**Spatial Resolution**} & \multicolumn{2}{c}{**Swath Width**} \\ \cline{2-6}
**Frequencies/Wavelengths** & **Pre-Boost** & **Post-Boost** & **Pre-Boost** & **Post-Boost** \\ \hline Visible and Infrared & 5 channels (0.63, 1.6, 3.75, & & & \\ Scanner (VIRS) & 10.8, and 12 μm) & 2.2 km & 2.4 km & 720 km & 833 km \\ \hline TRMM Microwave & 5 frequencies (10.7, 19.4, 21.3, & & 4.4 km at & 5.1 km at & 760 km & 878 km \\ Imager (TMI) & 37, 85.5 GHz) & 85.5 GHz & 85.5 GHz & & \\ \hline Precipitation Radar & 13.8 GHz & 4.3 km. Vertical: & 5 km. Vertical: & 215 km & 247 km \\ (PR) & & 250 m & 250 m & 250 m & 215 km & 247 km \\ \hline Lightning Imaging & 0.774 μm & 3.7 km & 4.3 km & 580 km & 668 km \\ Sensor (LIS) & & & & & \\ \hline \hline \end{tabular}
\end{table}
Table 1: Tropical Rainfall Measuring Mission (TRMM) precipitation and lightning instruments. To extend the mission lifetime, the TRMM orbit was boosted to 403 km in August 2001.  
The instruments on TRMM were turned off on 8 April 2015 and the spacecraft deorbited on 15 June. Over 17 years of valuable TRMM data have been collected by TRMM and available for weather and climate research.