Satellite-Based Meteorological and Agricultural Drought Monitoring for Agricultural Sustainability in Sri Lanka

Abstract

For Sri Lanka, as an agricultural country, a methodical drought monitoring mechanism, including spatial and temporal variations, may significantly contribute to its agricultural sustainability. Investigating long-term meteorological and agricultural drought occurrences in Sri Lanka and assessing drought hazard at the district level are the main objectives of the study. Standardized Precipitation Index (SPI), Rainfall Anomaly Index (RAI), and Vegetation Health Index (VHI) were used as drought indicators to investigate the spatial and temporal distribution of agriculture and metrological droughts. Climate Hazards Group Infrared Precipitation with Stations (CHIRPS) data from 1989 to 2019 was used to calculate SPI and RAI. MOD13A1 and MOD11A2 data from Moderate Resolution Imaging Spectroradiometer (MODIS) from 2001 to 2019, were used to generate the Vegetation Condition Index (VCI) and Temperature Condition Index (TCI). Agricultural drought monitoring was done using VHI and generated using the spatial integration of VCI and TCI. Thus, various spatial data analysis techniques were extensively employed for vector and raster data integration and analysis. A methodology has been developed for the drought declaration of the country using the VHI-derived drought area percentage. Accordingly, for a particular year, if the country-wide annual extreme and severe drought area percentage based on VHI drought classes is ≥30%, it can be declared as a drought year. Moreover, administrative districts of Sri Lanka were classified into four hazard classes, No drought, Low drought, Moderate drought, and High drought, using the natural-beak classification scheme for both agricultural and metrological droughts. The findings of this study can be used effectively by the relevant decision-makers for drought risk management (DRM), resilience, sustainable agriculture, and policymaking.

Spatio-temporal variability of droughts over the Mullaitivu District in Sri Lanka from 1980 to 2020

“…Studies on climate change have disclosed a significant temperature increase in many parts of Sri Lanka. Future climate change studies have also predicted an increase in temperature (Alahacoon & Edirisinghe, 2021a). As temperature increase is the vital source for drought occurrences, the future pattern of drought occurrences will also be in dense frequencies in the study area (Withanachchi et al, 2014).…”

A Novel Taxonomy for Risks in Agribusiness Supply Chains: A Systematic Literature Review

“…Since risk has been understood as "measurable uncertainty" [89], many researchers from different disciplines have developed methods and analysis tools to measure risk in their field of study [37,[94][95][96][97]. In the agricultural sector, for instance, farmers' risk preferences have been measured in the European agricultural context [98]; RADARSAT-2 is being used to monitor soil moisture to support risk reduction for the agriculture sector [99]; a TAMSAT-ALERT system is providing early warnings on meteorological risk to agriculture [100]; satellite-based meteorological and agricultural drought monitoring is available for agricultural sustainability in Sri Lanka [101]; and there are new perspectives on measurement, modelling, development and policies related to the income of farm families in Europe, especially in the light of increasing complexity of farms and policies on risk exposure [102]. Although researchers have developed either new operational frameworks or new perspectives on modelling to measure risks in agricultural sector, they have emphasised the crucial role of risk management in the agricultural sector [98][99][100][101][102][103].…”

Sustainability of Village Tank Cascade Systems of Sri Lanka: Exploring Cascade Anatomy and Socio-Ecological Nexus for Ecological Restoration Planning

“…The climate change and the food production nexus of the system provide many challenges and substantial trade-offs in terms of VTCSs sustainability [59,60]. Climate change increases the likelihood of extreme climatic events and is identified as a major driver that impacts food security and nutrition of the socio-ecological production landscapes [61][62][63][64][65][66][67][68][69]. The study adopted the climate change impact chain approach (http://cigrasp.pik-potsdam.de/about/ impactchains, accessed on 6 March 2021) to map climate-related impacts on resource subsystems of Mahakanumulla VTCS.…”