Researchers have just published the most thorough ever analysis of a late 19th-century drought that led to the Global Famine, an unprecedented disaster that took 50 million lives.
And, they warn, as earth’s climate warms, the same thing could happen again, only worse.
The researchers used tree-ring data, rainfall records and climate reconstructions to characterize the conditions leading up to the famine, a period of widespread crop failures across Asia, Brazil and Africa from 1876 to 1878.
The drought was linked to what may have been the most extreme manifestation of the El Niño climate cycle ever recorded.
“Climate conditions that caused the Great Drought and Global Famine arose from natural variability. And their recurrence — with hydrological impacts intensified by global warming — could again potentially undermine global food security,” wrote lead author Deepti Singh and her colleagues.
The study was just published in the Journal of Climate. Singh, who started the research while at Columbia University’s Lamont-Doherty Earth Observatory, is now an assistant professor at Washington State University.
The Global Famine was arguably one of the worst humanitarian disasters in history, killing as many people as the influenza epidemic of 1918-1919, World War I or World War II.
The deaths were caused in part by social and economic conditions in the Victorian colonial world, including British hoarding and exporting of grain from India.
Some impoverished populations were probably more vulnerable to disease because of colonial exploitation. But the immediate trigger was drought.
“In a very real sense, the El Niño and climate events of 1876-78 helped create the global inequalities that would later be characterized as ‘first’ and ‘third worlds’,” writes Singh, who was inspired by the 2002 book Late Victorian Holocausts, which details the impacts of the Great Drought. Its author, Mike Davis, is a coauthor on the paper.
Despite its enormous impact, few studies have characterized the natural dynamics of the drought. The new analysis is the first global-scale analysis of climatic conditions at the time.
The Great Drought actually was several droughts, beginning with a failure of India’s 1875 monsoon season.
East Asia’s drought started in the spring of 1876, followed by droughts in parts of South Africa, northern Africa and northeastern Brazil. There were also droughts in western Africa, Southeast Asia and Australia.
The length and severity of the droughts prompted the Global Famine, aided in no small part by one of the strongest known El Niños, the irregular but recurring periods when warm water dominates the surface in the tropical Pacific Ocean.
That in turn helped trigger the warmest known temperatures in the North Atlantic Ocean and the strongest known Indian Ocean dipole — an extreme temperature difference between warm waters in the west and cool waters in the east. These in turn triggered one of the worst droughts across Brazil and Australia, say the authors.
Because the events were induced by natural variations in sea-surface temperatures, says Singh, a similar global-scale event could happen again.
Moreover, rising greenhouse gas concentrations and global warming are projected to intensify El Niño events, in which case such widespread droughts “could become even more severe,” she said.
The exact socio-political factors that led to the famine no long exist, she said. Still, the authors write, “such extreme events would still lead to severe shocks to the global food system with local food insecurity in vulnerable countries potentially amplified by today’s highly connected global food network.”
The paper’s other authors are Richard Seager, Benjamin Cook, Mark Cane, Mingfang Ting and Edward Cook, all of Lamont-Doherty Earth Observatory.
This story is adapted from a press release by Eric Sorensen of Washington State University.
Source: Columbia University.