Grist: The streets of Ellicott City, Maryland, became raging rivers on Saturday, with cars tossed around like toy boats after nearly six inches of rain fell in just two hours. Rainfall that intense is a 1-in-1,000 year event for the area, according to the National Weather Service.
While downpours that intense are rare, heavy rainfall events have been on the rise in the region and nationwide thanks to the warming of Earths atmosphere caused by accumulating greenhouse gases. That trend is expected to...