Jack Johnson’s “To the Sea” rode a big curl to No. 1 on the U.S. album chart this week, enlivening an otherwise somnolent sales picture.The onetime surfer and soft-pop king’s new Brushfire release, his first studio album in two years, moved 243,000 units, according to Nielsen SoundScan data for the week ended June 6. It is Johnson’s third chart-topping release. The arrival of a No. 1 album selling more than 200,000 copies may have momentarily cheered retailers, but the rest of the week’s tallies reflect the sluggish musical climate. Justin Bieber’s “My World 2.0″ (Island) nipped up a notch to No. 2 with a mild 4% gain on 52,000 units. The latest “Glee” cast album “Showstoppers” (Columbia) tumbled two positions from No. 1 to No. 3, off 29% with a 45,000 unit week. The package will likely be joined in the top 10 next week by yet another spinoff from the Fox show, the EP “Journey to Regionals.” Several titles held their ground. Country trio Lady Antebellum’s “Need You Now” (Capitol Nashville) stuck at No. 4 with 41,000 sold (off 12%). R&B star Usher’s “Raymond v. Raymond” (LaFace) maintained at No. 5, shifting 35,000 (down 2%). And Lady Gaga’s 84-week-old “The Fame” (Interscope) hung on at No. 6 with 33,000 sold, gaining 6% after her appearance with Larry King. A major-market tour no doubt helped Carole King and James Taylor’s “Live at the Troubadour” (Hear Music) climb two slots to No. 7 with a 25,000-unit week. A pair of new releases shuffle in with unimpressive bows. R&B vocalist Taio Cruz’s “Rokstarr” (Mercury) arrived at No. 8 with a 24,000-unit bow. “American Idol” grad Clay Aiken’s collection of standards “Tried & True” (Decca) moved in at No. 9 with 22,000 sold. Ke$ha, still a factor on pop radio with “Your Love is My Drug,” moved back into the top 10; her 22-week-old set “Animal” (Kemosabe/RCA) leapt seven positions to No. 10, selling 20,000. The new “Glee” EP, the soundtrack album for the much-anticipated third “Twilight” film “Eclipse” and Christina Aguilera’s first studio album in four years will enliven the chart next week.