Atlantic Media, publisher of The Atlantic magazine, said it will cut about 20 percent of its staff in response to the advertising collapse tied to the coronavirus crisis. Chairman David Bradley, a billionaire, revealed the news in a memo to staffers on Thursday. “This morning, we are informing 68 of our colleagues that we will not have a place for them on The Atlantic’s new course. The contraction affects mainly our events, sales and editorial staffs.” He said for the remaining 80 percent of the staff, there will be “pay cuts for executives and a general pay freeze for the rest of the year.” Of the cuts about 22 came from the editorial, including the entire video team, which the company is shutting down. A company spokeswoman said that while digital traffic was surging and the print version has had 90,000 new subscribers in the past two months, the added revenue is not enough to offset the advertising plunges and the loss of income from paid conferences.