The Leviathan Effect

Homeland Security Secretary Catherine Blaine receives a frightening communication from a hacker identified only by the pseudonym "Janus": three recent natural disasters around the world were correctly predicted—in fact, they were manufactured, not natural at all. And, says the email, unless she does exactly as Janus instructs, more disasters are coming—and they will destroy the United States.
 
Unaware of the crisis in Washington, investigative journalist Jon Mallory stumbles on a list of seven prominent scientists who have been murdered in recent months. When the person who had given him the list goes missing herself, Jon realizes he has unwittingly become part of a deadly chain of events. He contacts his brother, ex-CIA agent Charles, looking for help. Meanwhile, Catherine Blaine has also come to Charles for help to track down the hacker Janus and learn what frightening science is threatening the world.