IPWG Project:

Precipitation is difficult to measure and predict. Each year droughts and floods cause severe property damages and human casualties around the world. Accurate measurement and forecast are important for mitigation and preparedness efforts. Significant progress has been made over the past decade in satellite precipitation product development. In particular, products’ spatial and temporal resolutions as well as timely availability have been improved by blended techniques. Their resulting products are widely used in various research and applications. However biases and uncertainties are common among precipitation products and an obstacle exists in quickly gaining knowledge of product quality, biases and behavior at a local or regional scale, namely user defined areas or points of interest. Current online inter-comparison and validation services have not addressed this issue adequately. To expedite the use of satellite precipitation products, the obstacle needs to be removed.

We have developed a Technology Readiness Level 7 (TRL-7) prototype (http://disc2.nascom.nasa.gov/Giovanni/tovas/rain.ipwg.shtml) in the TRMM Online Visualization and Analysis System (TOVAS) to address this issue (Liu et al. 2009, IPWG Special Issue in Journal of Applied Meteorology and Climatology). Despite its limited functionality and datasets, users can use this tool to generate customized plots within the United States for 2005. In addition, users can download customized data for further analysis, e.g. comparing their gauge data.
 
To meet increasing demands, we propose to integrate IPWG (International Precipitation Working Group) Validation Algorithms/statistics into TOVAS, allowing users to generate customized plots and data.  In addition, we will expand the current coverage from the United States to global for daily, monthly and their climatology products. Whenever the TRMM science team changes their product version number, users would like to know the differences by inter-comparing both versions of TRMM products in their areas of interest. Making this service available to users will help them to better understand associated changes. We plan to implement this inter-comparison in TRMM standard monthly products with the IPWG algorithms. Monthly precipitation and their climatology products are important for many applications. Knowing differences among them will help researchers and application users. We plan to expand the existing monthly products and services.

The proposed additions will complement and accelerate the existing and ongoing validation activities in the community as well as enhance data services for TRMM and the future Global Precipitation Mission (GPM).

Giovanni TOVAS Instances:

Beta Prototype: TRMM L-3 V6 and V7 Inter-comparison
Beta Prototype: Inter-comparison of 3B42RT and 3B42
Prototype Interactive Intercomparison of Rainfall Products
Inter-Comparison of Rainfall Climatology
Giovanni TOVAS
New: Giovanni-4

Project Publications and Presentations:

Liu, Z., 2015,  Comparison of Precipitation Estimates between Version 7 3-Hourly TRMM Multi-Satellite Precipitation Analysis (TMPA) Near-real-time and Research Products. Joint between the 20th Conference on Satellite Meteorology and Oceanography; the 11th Annual Symposium on New Generation Operational Environmental Satellite Systems; and the Third Symposium on the Joint Center for Satellite Data Assimilation, AMS Annual Meeting, Phoenix, 4-8 January 2015.

Liu, Z., 2015, Comparison of precipitation estimates between Version 7 3-hourly TRMM Multi-Satellite Precipitation Analysis (TMPA) near-real-time and research products. Atmospheric Research, Volume 153, February 2015, Pages 119–133, Online: http://www.sciencedirect.com/science/article/pii/S0169809514003081

Liu, Z., 2015, Comparison of Versions 6 and 7 3-Hourly TRMM Multi-Satellite Precipitation Analysis (TMPA) Research Products. Atmospheric Research, in press, Online: http://www.sciencedirect.com/science/article/pii/S0169809515000046

Liu, Z., 2014, Online Comparison of Precipitation Products during the GPM Era. Session: Utilizing Precipitation Data Sets and Quantifying Associated Uncertainties in Hydrometeorological and Climate Impact Applications I, AGU Fall Meeting, San Francisco, 15-19 December 2014.

Liu, Z., 2014, Online Intercomparison of Satellite-based Global Precipitation Products: Challenges, Progress and Future Directions. The 7th IPWG Workshop on Precipitation Measurements, Tsukuba, 17-21 November, 2014.

Liu, Z., 2014, Comparison of global precipitation climatology products derived from ground- and satellite-based measurements. Remote Sensing of the Atmosphere, Clouds, Precipitation V, SPIE Asia-Pacific Remote Sensing , Paper 9259-6, Beijing, China.

Liu, Z., Ostrenga, D., Teng, W., Kempler, S., Milich, L., 2014, Developing GIOVANNI-based online prototypes to intercompare TRMM-related global gridded-precipitation products, Computers & Geosciences, volume 66, issue , year 2014, pp. 168 - 181

Liu, Zhong,  Dana Ostrenga, William L. Teng, and Steven J. Kempler, 2013. Implementing the International Precipitation Working Group (IPWG) Validation Statistics in Online Tools to Inter-compare and Characterize Satellite-derived Global Precipitation Products. 2013 American Geophysical Union Fall Meeting in San Francisco, 9-13 December 2013.

Ostrenga, Dana;  Zhong Liu, Steven J. Kempler, Bruce Vollmer, and William L. Teng, 2013. Preparing Precipitation Data Access, Value-added Services and Scientific Exploration Tools for the Integrated Multi-satellitE Retrievals for GPM (IMERG). 2013 American Geophysical Union Fall Meeting in San Francisco, 9-13 December 2013.

Liu, Z., D. Ostrenga, W. Teng, and S. Kempler, 2013: Online Tools to Inter-compare TRMM Precipitation Products, 93nd AMS Annual Meeting, Jan 6-10, Austin, TX

Liu, Z., D. Ostrenga, D. W. Teng, and S. Kempler, 2012, Utilizing Satellite-derived Precipitation Products in Hydrometeorological Applications (Invited), American Geophysical Union (AGU) 2012 Fall Meeting. December 3-7, 2012, San Francisco, CA

Liu, Z., D. Ostrenga, W. Teng, S. Kempler, 2012, Online Inter-comparison of Satellite-derived Global Precipitation Products,  Sixth Workshop of the International Precipitation Working Group, 15-19 October 2012, Sao Jose dos Campos, Brazil.

Liu, Z, 2012, International Training on Satellite-derived Global Precipitation Products and Services,  Sixth Workshop of the International Precipitation Working Group, 15-19 October 2012, Sao Jose dos Campos, Brazil.

Liu, Z., D. Ostrenga, W. Teng, S. Kempler, 2012, TRMM Data Services at the NASA GES DISC, New and Emerging Technologies, Sensors, and Datasets for Precipitation at the  Sixth Workshop of the International Precipitation Working Group, 15-19 October 2012, Sao Jose dos Campos, Brazil.

Liu, Zhong, 2012. Developing Online Tools to Assess Uncertainty in Satellite-derived Global Precipitation Products. Climate Informatics 2012, Boulder, Colorado (selected for a partial travel fellowship support).

Liu, Z, and D. Ostrenga, W. Teng, and S. J. Kempler, 2012, Online Assessment of Satellite-Derived Global Daily Precipitation Products, 92nd AMS Annual Meeting, Jan 22-26, New Orleans, LA

Liu, Z, and D. Ostrenga, W. Teng, and S. J. Kempler, 2011, Online Evaluation of Satellite-Derived Global 3-Hourly Precipitation Products, American Geophysical Union (AGU) 2011 Fall Meeting. December 5-9, 2011, San Francisco, CA
Acknowledgements: This project is supported by NASA Research Opportunities in Space and Earth Science- 2010 (ROSES-2010), NNH10ZDA001N-ESDRERR, Appendix A.32: “Earth System Data Records Uncertainty Analysis” and the NASA GES DISC.

Acknowledgements: This project is supported by NASA Research Opportunities in Space and Earth Science- 2010 (ROSES-2010), NNH10ZDA001N-ESDRERR, Appendix A.32: “Earth System Data Records Uncertainty Analysis” and the NASA GES DISC.