A low-cost, low-tech climate solution that saves lives
Early warnings systems for extreme weather can sharply reduce death tolls when storms hit, and they don’t need to be complicated.
By Somini Sengupta April 8, 2022
How do you save lives in an era of cascading climate disasters? You warn people of the dangers approaching. You give them time to get out of harm’s way — and a place to take shelter.
These are the main elements of what is called an early warning system. It’s a relatively low-tech, low-cost way to reduce the death toll from storms, heat waves and wildfires. Every country should put them in place in the next five years, the United Nations says.
Accuracy matters. The more precisely forecasters can track the path of a tropical cyclone, for instance, the more accurately government officials can pinpoint which areas should evacuate.
Timing matters, too. A three-day advance forecast is more helpful than two, government officials and aid workers say.
And then, there’s trust. One study found that when citizens trust their public officials, they are more likely to evacuate when they are warned.
Bangladesh is among the countries credited with saving many lives with its early warning system. I asked Kawsar Parvin, the deputy director of the Bangladesh Meteorological Department in Dhaka, how it works.
She told me alerts go out three to five days in advance of a potentially disastrous weather event: extreme cold, heat, cyclones and heavy rains. Bangladesh has a particularly sophisticated, battle-tested system for cyclones.
Radio and television news outlets broadcast weather warnings. But the real dissemination happens with an army of 76,000 volunteers. When a cyclone is on the way, they fan out across their own communities. They hoist a series of flags to convey the level of risk: One flag signals a cyclone is predicted to make landfall in the area, two flags signal imminent danger, three flags mean the highest level of danger.
With loudspeakers and megaphones, on bicycle rickshaws and three-wheeled cycles, they spread the news to their neighbors, street by street: A cyclone is coming. Get out of the way. Go to a shelter.
Women make up half of the volunteer force, Achala Navaratne, the Bangladesh country representative for the Red Cross, told me. That’s important for gender equity, but also to make sure women hear from other women. “Ensuring early action is the critical factor,” he said. “Having community volunteers from their own community helps.”
Bangladesh has long been vulnerable to cyclones that form over the Bay of Bengal. Climate change can intensify the strength and frequency of cyclones.
There are more than 5,000 permanent cyclone shelters in Bangladesh. Twice as many shelters had to be established during Cyclone Amphan, which barreled toward Bangladesh in May 2020, amid the coronavirus pandemic. More space was needed for physical distancing. All told, 2 million Bangladeshis were evacuated from their homes, along with 500,000 cattle and goats. Livestock is often a rural family’s main source of livelihood and asset — their paycheck and their savings account. They, too, have to be accounted for in early warning efforts.
The World Meteorological Organization cites the Cyclone Amphan precautions as a model of effective early warning. The death toll was limited to 72 people in Bangladesh.
“Bangladesh can share multiple lessons to other countries on good preparedness,” Navaratne said.
The United Nations Secretary General, António Guterres, recently tasked the W.M.O. to come up with a global plan to cover everyone on earth with early warning systems.
A third of the global population is not covered, and that share is far higher for the people of Africa. “This is unacceptable,” Mr. Guterres said, “particularly with climate impacts sure to get even worse.”
Just creating an early warning system isn’t enough, though.
Take the case of Brazil. In February, meteorologists failed to forecast the extraordinary rains that pummeled the hills above Rio. In three hours came 10 inches of rainfall on the city of Petrópolis, the highest rainfall since records began in 1932. The mudslides that followed killed more than 200 people, Marcelo Seluchi, who coordinates modeling and operations for the country’s early warning system, told my colleague Manuela Andreoni. By contrast, accurate predictions of extreme rains in Minas Gerais and Bahia states, also this year, limited the death toll to about 20 in each state.
Or, look at what happened in Germany last summer. European meteorologists issued an “extreme” flood alert. German officials told my colleagues at the time they had never before seen so much rain falling so fast. The message to get out of harm’s way didn’t get through to the public. Tough questions were raised in the following months about why local officials did not act on flood warnings more aggressively.
Disasters are costly in human terms. Over the last 50 years, weather and water-related disasters have claimed 115 lives and exacted an estimated $202 million in losses on average every day, according to a 2021 study by the World Meteorological Organization.