" alarmist "

 [ "alarmist" ]

1: Someone who is always jumping to conclusions or thinking the worst. The person is generally scared of something bad happening to them.

  * e.g.,  ... When the economy started dropping all the alarmists in the world starting spending dump loads of money to try and fix it. 

 [ "Global Alarmist" ]

1: Individual that strives to stay fashionable and correct by warning others of global warming when they themselves have no basic grasp of earth science. These were the same type of individuals that warmed of global cooling in the 60's. When asked simple earth science questions like "what is the pleistocene epoch?", or "what was the name of the last ice age", they get defensive. When asked if they should be more worried about an asteroid, they giggle and say that's just in the movies.

  * e.g.,  ... The global alarmist warned of melting glaciers even though the professor of atmospheric science tried to tell him there are areas of increased glaciation in progress.