Assessment of a Spatially and Temporally Consistent MODIS Derived NDVI Product for Application in Index-Based Drought Insurance

Remote Sensing

Robert Griffin¹  SaraE. Miller¹  Daniel Irwin²  Ashutosh Limaye²  Richard Kyuma³  KelN. Markert⁴  EricR. Anderson⁴  W.Lee Ellenburg⁴  EmilyC. Adams⁴  Lilian Ndungu⁵ 

[1] Department of Atmospheric Science, The University of Alabama in Huntsville, 320 Sparkman Dr., Huntsville, AL 35805, USA;Earth Science Branch, Marshall Space Flight Center, 320 Sparkman Dr., Huntsville, AL 35805, USA;Kenya Ministry of Agriculture, Livestock, Fisheries, and Irrigation, P.O. Box 30028-00100, Cathedral Road, Nairobi 00100, Kenya;NASA SERVIR Science Coordination Office, Marshall Space Flight Center, 320 Sparkman Dr., Huntsville, AL 35805, USA;The Regional Centre for Mapping of Resources for Development, Kasarani, Nairobi 00618, Kenya;

关键词: NDVI;    Kenya;    index-based insurance;    livestock;   

DOI  :  10.3390/rs12183031

来源: DOAJ

【 摘 要 】

In arid and semi-arid regions of Eastern and Southern Africa, drought can be devastating to pastoralists who depend on healthy vegetation for their herds. The Kenya Livestock Insurance Program (KLIP) addresses this challenge through its insurance program that relies on a vegetation index product derived from eMODIS NDVI (enhanced Normalized Difference Vegetation Index). Insurance payouts are triggered when index values fall below a certain threshold for a Unit Area of Insurance (UAI). The objective of this study is to produce an updated, cloud-based NDVI product, potentially allowing for earlier payouts that may help herders to prevent, minimize, or offset drought-induced losses. The new product, named reNDVI (rapid enhanced NDVI), provides an updated cloud filtering algorithm and brings the entire processing chain to the cloud. Access to the scripts used for the processing described and resulting data is openly available. To test the performance of the new product, we provide a robust evaluation of reNDVI and eMODIS NDVI and their derived payout indices against historical drought, payouts provided, and mortality data. The implications of potential payout differences are also discussed. The products show good comparability; the monthly average NDVI per UAI has correlation values over 0.95 and MAPD under 5% for most UAIs. However, there are moderate differences when assessing year-to-year payout amounts triggered. Because the payouts are currently calculated based on the 20th and first percentile of index values from 2003–2016, payouts are very sensitive to even small changes in NDVI. Where livestock mortality was available, payouts for reNDVI and eMODIS had similar correlations (r = 0.453 and r = 0.478, respectively) with mortality rates. Therefore, with the potential reduced latency and updated cloud filtering, the reNDVI product could be a suitable replacement for eMODIS in the Kenya Livestock Insurance Program. The updated reNDVI product shows promise as a vegetation index that could address a pressing drought insurance challenge.

【 授权许可】

Unknown