After years of scant rainfall in a remote region of Sri Lanka, farmer Renuka Karunarathna's crops failed and as the family's income dwindled, her husband took his anger out on her, beating her so badly she had to go to a hospital.

"I have got beaten up so many times," Karunarathna told said in her village of Sapumal Thenna in Sri Lanka's North Central Province. "I suffer a lot."

Domestic violence is a little-studied side effect of climate change, especially in poorer nations where increasingly frequent heat waves, droughts, floods and storms can exacerbate economic hardship, which in turn can fuel anger and violence.