Development of precision estimation method of rainfall erosivity for better understanding of soil erosion in data-sparse regions

2019 Fiscal Year Research-status Report

• Project/Area Number: 19K13434
• Research Institution: Tottori University
• Principal Investigator: FENTA AYELE・ALMAW 鳥取大学, 乾燥地研究センター, プロジェクト研究員 (00836984)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: Rainfall intensity / Rainfall erosivity / Satellite rainfall / Soil erosion

Outline of Annual Research Achievements

The purpose of this research is to develop precision estimation method of rainfall erosivity for the highland regions of Ethiopia by integrating data from ground-based rainfall measurements and satellite rainfall estimates (SREs). So far, the following research activities have been acomplished:
1. In 2019, HOBO RG3-M - Automatic Rain Gauges have been installed across the Blue Nile basin in Ethiopia and rainfall intensity data have been collected for one season.
2. To complement the rainfall intensity data being collected using the automatic rain gauges, historical daily rainfall data for about 50 rainfall stations was purchased from the regional and national meteorology agency of Ethiopia.
3. Five years of satellite rainfall data (Global Satellite Mapping of Precipitation [GSMaP] and Integrated Multi-satellite Retrievals for GPM [IMERG]) were downloaded from the JAXA and NASA websites.
4. Preliminary analysis of evaluating the GSMaP and IMERG rainfall estimates using the ground-based measured rainfall data has been done.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

So far, the research activity is progressing rather smoothly as I was able to install the monitoring stations before the rainy season in July 2019 and also purchased the daily rainfall data which is necessary for evaluation of satellite rainfall estimates.

Strategy for Future Research Activity

Future research activities include:
1. Install additional monitoring stations and maintain existing ones.
2. Perform rigorous evaluation of the satellite rainfall estimates ground-based rainfall measurements.
3. Integrate improved satellite rainfall estimates and erosivity models to estimate annual rainfall erosivity for the Blue Nile basin in Ethiopia.
4. Model regional-scale soil erosion risk by integrating improved rainfall erosivity estimates with other erosion factors to support improved environmental conservation planning.

Causes of Carryover

One of the reasons to carry over 922,114JPY of FY2019 budget to the next fiscal year was that I replaced the plan to purchase disdrometer with ATMOS all-in-one weather station (relatively cheaper). In addition, initially the plan was to purchase 15 HOBO RG3-M - Automatic Rain Gauges but in FY2019 only 5 were purchased and the remaining ones will be purchased in FY2020.
The budget usage plan for FY2020 including the carried-over budget is to cover travel expenses to study site and conference presentation as well as to purchase the following items to be used for the research purpose: 1. HOBO RG3-M - Automatic Rain Gauges; 2. Handheld GPS (complete set); 3. EC/TDS/Resistivity/Salinity Meter; 4. TD-Diver and BARO-Diver

Research Products

• [Presentation] Assessment of water and wind erosion risk over the Eastern Africa region (2019)
  • Author(s): Fenta, A. A., Tsunekawa, A., Haregeweyn, N., Poesen, J., Tsubo M., Borrelli, P., Panagos, P., Vanmaercke, M., and Broeckx, J.
  • Organizer: Global Symposium on soil erosion
  • Int'l Joint Research