impact on the region’s environment and biodiversity,” said lead author Ashok Mishra, UCI associate professor of civil and environmental engineering. “We looked at satellite data and, through computer simulations based on physical principles, found a fingerprint of human-induced climate change.” The team found that the drying in southern Madagascar is primarily being driven by human activities, particularly the burning of fossil fuels, which has warmed the Indian Ocean and driven a change in atmospheric circulation patterns. This has resulted in a decrease in precipitation and an increase in temperatures in the region over the past six decades.”
Angela Rigden, an assistant professor of Earth system science at UC Irvine and the lead author of the study, discussed the implications of the changing climate on the people of southern Madagascar and their agricultural practices. According to Rigden, the region’s rainy season is becoming shorter, causing a delay in its onset. To make the connection between the drought and climate change, the team used a multi-year satellite record of vegetation greenness to track changes in water availability in southern Madagascar. This satellite-based remote sensing data of plants was then linked to the amount of available water in the soil.The rainy season window has shifted, aligning with predictions made by some climate models in the absence of human-driven climate change. This shift is considered to be a result of climate change, specifically the change in seasonality, according to Rigden. Additionally, the multi-year satellite record, dating back to the early 1980s, has provided valuable data for observing changes attributable to climate. This is especially important for less developed and poverty-stricken areas like southern Madagascar, where long observational records are only available from satellites.Rigden stated, “Additionally, these observations strongly align with climate models that indicate shifts in the timing of seasons.”
Christopher Golden, a study co-author and an associate professor of nutrition and planetary health at the Harvard University T.H. Chan School of Public Health, has conducted fieldwork in Madagascar for the last 25 years. He noted that southern Madagascar is a dry region, even in the absence of drought conditions, and local residents have witnessed changes in rainfall patterns over the years.
Furthermore, colleagues at Catholic Relief Services and the USAID are involved in the study.Mission to Madagascar, the key stakeholders in the study, informed Golden about the challenges the country is facing. Rigden’s interest in the study was sparked by the United Nations’ declaration of a famine in southern Madagascar due to climate change in 2021. She was curious to see what insights satellite data could provide about the situation.
“Our findings indicate that climate change is the main driver of this phenomenon,” stated Golden. She also mentioned that the study will enable scientists to offer more confident recommendations to policymakers who determine where to allocate relief aid globally. “The evidence suggests that this is a persistent issue that will continue to worsen.””Climate change has been linked to drought in Southern Madagascar for quite some time,” stated Golden, providing valuable information that can be used to justify the funding for relief efforts.
By understanding that events like droughts are no longer unexpected occurrences but rather a regular part of the future, communities can be better prepared. “We can develop methods to adjust,” explained Rigden.
The funding was provided by Catholic Relief Services (Madagascar) as part of their partnership and funding agreements with USAID.
Journal Reference:
- Angela Rigden, Christopher Golden, Duo Chan, Peter Huybers. Climate change linked to drought in Southern Madagascarpublished in npj Climate and Atmospheric Science in 2024 with the reference DOI: 10.1038/s41612-024-00583-8