Global scale analysis of drought impact on croplands: a remote sensing approach
Abstract
Drought is one of the extreme climatic events that have a severe impact on crop production and can lead to food insecurity. Our main goal is to use several moderate resolution remotely sensed time series for capturing spatiotemporal patterns of crop growth under different agro-climatic conditions and characterize the duration and spatiotemporal variability of drought. Furthermore, we conducted tests to show the extent of yield variability that can be explained by remote sensing-based indicators. Several datasets derived from Moderate Resolution Imaging Spectroradiometer (MODIS) imagery, spanning from 2001 to 2017, were used. This includes 16-day Normalized Difference Vegetation Index, Land Surface Temperature, and Evaporative Stress Index (ESI), based on the ratio of Actual to Potential Evapotranspiration. These indices were used as an indicator of drought-induced vegetation condition for three main crops: maize, wheat and soybean. Using monthly composites, anomalies for each indicator were estimated. Furthermore, crop phenological indicators were used in order to mask any anomalies outside the growing season based on the timing of greening and senescence. We further integrated the remote sensing based information of impacted croplands with socioeconomic indicators, such as, population density, gross domestic product, percentage of irrigated agricultural land. Anomalies in ESI had higher correlations with soybean and maize yield anomaly than other indices, indicating that prolonged periods of low ESI during the growing season are highly correlated with reduced crop yields. All indices could identify the past drought events, which were described as significant drought events, e.g. in the United States in 2012, Eastern Africa in 2016-2017 as well as South Africa in 2015/2016. The results of this study highlight the potential of the use of remote sensing-based indicators for drought-induced crop impact monitoring. The integration of phenometrics considerably improved the drought impact monitoring. The used indices can be integrated into drought early warning systems and crop yield models. In addition, they could be beneficial for risk assessment and included in advanced decision-support frameworks.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMH178...07G
- Keywords:
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- 1807 Climate impacts;
- HYDROLOGY;
- 1812 Drought;
- HYDROLOGY;
- 1920 Emerging informatics technologies;
- INFORMATICS;
- 4327 Resilience;
- NATURAL HAZARDS