The earthquake on March 11, 2011, was the largest ever to hit Japan. A tsunami with 30-foot waves followed; nearly 20,000 people died, and 2,500 were never found.
"Before 2011, I had never thought about disaster prevention deeply," Tanaka, 29, wrote in an email.
She had participated in school drills as a student, "of course, I didn't feel it is important," she said.
But the earthquake -- which moved Honshu
, Japan's main island, 8 feet and literally shifted the Earth on its axis, according to the US Geological Survey -- made Tanaka see things differently.
Her thoughts and actions changed in ways that surprised even herself.
"I couldn't stop thinking about it," she says. She quit the job in IT that she loved and moved to the disaster area, Fukushima prefecture, to help people.
"In Fukushima, I saw a lot of refugees and collapsed houses and places where all the towns were washed away by the tsunami," she said. "I talked with many people who lost friends and family."
Tanaka decided to spread the word about the importance of disaster relief to Japanese citizens. On March 11, 2013, the second anniversary of the devastating earthquake, she and a couple of friends founded an organization called the Bosai Girls.
" 'Bosai' means 'disaster prevention' in Japanese," Tanaka said, so the name of the group simply means "girls take action to prevent disaster!"
The website of the Bosai Girls
makes this message clear: "Earthquake, volcano, heavy rain, typhoon. Living in Japan is to live with nature... and disaster."
Two Chinese characters are needed when you write "Bosai" in Japanese, Tanaka explains. The first means "prevention or prepare," she says, while, historically, the Japanese have interpreted the second character to mean "natural disaster."
There's an excellent explanation for this.
"(Japan) is one of the most earthquake-prone places on the Earth," said Mark Petersen, chief of the National Seismic Hazard Modeling Project with the US Geological Survey. He notes that yearly, there are 1,500 or more quakes of a magnitude