Limited role of climate change in extreme low rainfall associated with southern Madagascar food insecurity, 2019–21

Abstract

Southern Madagascar recently experienced a severe food security crisis, made significantly worse by well below average rainfall from July 2019 to June 2021. This exceptional drought has affected a region with high pre-existing levels of vulnerability to food insecurity (subsistence agriculture and pastoralism in the region is rain-fed only), while impacts have been compounded further by COVID-19 restrictions and pest infestations. The rainy seasons of both 2019/20 and 2020/21 saw just 60% of normal rainfall across the Grand Sud region and was estimated as a 1-in-135 year dry event, only surpassed in severity by the devastating drought of 1990-92. Based on a combination of observations and climate modelling, the likelihood of experiencing such poor rains in the region was not significantly increased due to human-caused climate change: while the observations and models combine to indicate a small shift toward more droughts like the 2019-2021 event as a consequence of climate change, these trends remain overwhelmed by natural variability. This result is consistent with previous research, with the IPCC’s Sixth Assessment Report concluding that any perceptible changes in drought will only emerge in this region if global mean temperatures exceed 2°C above pre-industrial levels.

Multiyear dry periods in Southern Africa

“…In Region 4 (Figure 3d), few prolonged dry periods are also found, and the time period centered around 2010 stands out as the most consistently dry epoch. Though our analysis ends in 2014 so as to encompass only the historical forcing of the SPEAR simulations, the dryness in Madagascar at the end of the historical record extends beyond 2014 (Harrington, 2021).…”

Clarification on protected area management efforts in Madagascar during periods of heightened uncertainty and instability

“…Prescribed burning was used as a management practice in most large NPs in the dry biome from February to April/May and cannot be distinguished or qualified as such with satellite information. Prescribed burning was enhanced during 2020 in anticipation of increased drought and modeled fire risk (Prasetya et al 2019, Harrington et al 2021, Figure 1). These intentional burns were conducted in grasslands within the PAs to reduce fuel loads and to preclude fires from entering the forests, a priority element in MNP's management strategy to safeguard forest biodiversity.…”

Harbingers of decades of unnatural disasters

“…Over the 24 months from July 2019 to June 2021 rainfall was very low, estimated as approximately a 1-in-135 year dry event, and in the observed record only surpassed in severity by a severe drought in 1990-92. Based on a recent attribution study conducted by a large group of scientists 29 , the occurrence of poor rains as observed from July 2019 to June 2021 has not significantly increased due to anthropogenic climate change. Importantly, this result is consistent with previous research on droughts in the region 30,31 and in line with the IPCC's Sixth Assessment Report 1 which does not expect changes in drought frequency and intensity at current warming levels.…”

“…The Southern region is poorly connected in terms of infrastructure 38 which makes it hard for humanitarian aid to reach, again highlighting a development problem. This drought spanning over a long period of time, complicated with the ongoing COVID-19 pandemic has thus further exacerbated people's poverty (see Harrington et al 29 ), including a lack of seeds to plant in the next season, potentially prolonging the cycle of poor harvests and extreme poverty well beyond the end of the physical hazard. Yet another case to highlight that disasters are rarely natural and that only taking the hazard as well as different aspects of vulnerability into account allows to identify the important drivers of disasters and consequently where to focus development and adaptation efforts.…”