Researchers used supercomputer simulations to confirm that deadly heat waves in India and Pakistan during the summer of 2015 were made worse by climate change.
The two countries typically suffer extreme heat in the summer, but in 2015, a heat wave in late May and early June in India caused 2,500 deaths, while a separate heat wave between late June and early July in Pakistan killed 2,000 people.
Researchers from Lawrence Berkeley National Laboratory (LBNL), the Indian Institute of Technology Delhi and UC Berkeley analyzed observational and simulated temperature and heat indexes and concluded that the two separate heat waves “were exacerbated by anthropogenic climate change,” according to a story on LBNL’s website.
To analyze the data, the researchers used two Intel Xeon-based supercomputers: the Edison and Cori supercomputers at the lab’s National Energy Research Scientific Computing Center (NERSC).
As part of their analysis, they analyzed “counterfactual” simulations on how the weather would have been if humans had not changed the composition of the atmosphere by creating large amounts of carbon dioxide, the story said.
“Observations suggested the human influence; simulations confirmed it,” said Michael Wehner, a climate researcher at LBNL and lead author of a just published study called “The Deadly Combination of Heat and Humidity in India and Pakistan in Summer 2015.”
The paper was was recently published in the Bulletin of the American Meteorological Society.