The 31-year-old singer, who was hospitalized for a mental and physical breakdown in July, and relapsed in September, will sing her 1993 hit "Hero," a publicist for Virgin Records told Reuters.
The telethon, which is being produced by Joel Gallen of MTV Movie Awards fame, will raise money through telephone and online donations for the victims. Music and television artists are donating their time and talents on the show.
According to TV Guide, the event will take place in Los Angeles and New York and air Friday at 9 p.m. live in Eastern and Central time zones and tape-delayed in the Mountain and Pacific time zones.
The Spanish-language channels Univision and Telemundo, PBS, radio stations, and Yahoo! will broadcast the show, Reuters reported.
According to the Hollywood Reporter, Carey's Aug. 21 album release, Glitter, has received poor reviews by critics and fans, falling below expectations with a No. 7 debut on 116,325 units scanned, according to SoundScan figures.