All of the different "alerts" that I'm aware of:
Amber = America's Missing: Broadcast Emergency Response is sent to the public when a child/minor has been abducted or believed to be in danger of death, sexual assault or bodily injury.
Clear = A CLEAR (Coordinated Law Enforcement Adult Rescue) Alert is similar to an AMBER Alert, but it is sent out for an adult rather than a child. I've personally never seen one of these but I know they exist.
Silver = I see these on the interstate all the time. A Silver Alert notifies the public when a elderly individual with a documented medical condition is missing. For this type of alert to be sent out, the missing person must 65 years old or older and have a diagnosed medical impairment.
Camo = A Camo Alert informs the public that a current or former member of the United States armed forces, including the National Guard or a reserve, with a mental illness is missing. This is another one that I've never seen despite living in a large population of military retirees and MacDill AFB.
Blue = A Blue Alert makes the community aware of a criminal wanted by law enforcement who has killed or seriously wounded a local, state, or federal law enforcement officer. I've seen this once.
Purple (specific to Florida) = The Florida Purple Alert is a system designed to help locate missing adults who have a mental or cognitive disability that does not stem from Alzheimer's disease or dementia-related disorders, brain injuries, intellectual or developmental disabilities. I see this one nearly as often as I see a silver alert.
I think some other states, like California, have color alerts specific to their highway notification systems. Like I think Cali might have a yellow alert but I don't know what it is for. This so-called Ebony Alert is just another one in a line that is getting so long that we are going to need a color wheel to keep track of them.