“A Sea in Flames” is written in a clear, conversational style. There is considerable detail but no daunting techno-­babble: readers will find the book accessible and agreeable. Safina relates a bit more than perhaps necessary about what he heard on the radio while driving around the Gulf Coast, and repeatedly relies on anonymous quotations, for no apparent reason. He will quote “a certain tugboat captain” or “a New Orleans businessman who loves the bayou” without any hint of why their names should be withheld. Readers might be suspicious: if the author interviewed these people, why doesn’t he mention their names? Safina attaches considerable significance to George W. Bush’s attempt to suppress global warming science (this subject is a standby of Al Gore talks) without noting (neither does Gore) that the hush-up failed. In 2006, the federal Climate Change Science Program, under Bush, declared “clear evidence of human influences on the climate system.”

These minor faults aside, “A Sea in Flames” is an insightful work. Safina zaps Sarah Palin for calling BP “foreign” — her husband, Todd, worked for BP for years — and for her loopy implication that Alaska would welcome another oil spill. He documents the weirdness of BP’s posting private guards who closed off public beaches to keep journalists and witnesses away; local, state and federal authorities did nothing. “The flow BP is getting good at stopping is the flow of news,” Safina observes. He blasts Congress for demanding cheap oil, no questions asked; lauds Obama for twisting BP’s arm to put $20 billion into a compensation fund (the company’s liability limit was lower, and ExxonMobil stalled the final Exxon Valdez payments for an incredible 19 years); laments that people who tried to observe soiled beaches were threatened with arrest, while no one from BP was charged with any crime; and, though sympathetic to local fishermen, acknowledges that many fakers demanded compensation they did not deserve.

“A Sea in Flames” makes considerable sport of Adm. Thad Allen of the Coast Guard — whose early role appeared to be to say, “Aye, aye, sir!” to BP — and of the Frick and Frack of the gulf follies, Interior Secretary Ken Salazar and Jane Lubchenco, administrator of the National Oceanic and Atmospheric Administration. Salazar had been in office more than a year before the spill but failed to notice that having the Interior Department’s Minerals Management Service (since disbanded) both encourage offshore oil production and certify its safety was a perilous conflict. Lubchenco, a prominent environmental pessimist when outside government, became an apologist once inside: Safina has fun with her denying there were oil “plumes,” insisting instead that only “anomalies” existed. Salazar and Lubchenco both graduated from landlocked Colorado College, a top liberal arts school but, a thousand miles from seawater, perhaps ill suited to prepare them for April 2010.

As “A Sea in Flames” progresses, its author undergoes several conversions. Expecting to find evidence of terrible harm to the gulf biosphere, instead he finds only mild problems. Expecting to discover that the dispersants caused widespread marine death, instead he discovers that by breaking up crude, these chemicals speeded the oil’s natural decomposition. After Allen and Lubchenco grant him an interview, Safina switches ground and decides they are not as bad as he thought.

By the end, Safina is nearly a contrarian. Fertilizer runoff from the Mississippi, he concludes, causes the gulf more harm than did BP, while the fishing ban that went into force just after the spill might have helped marine wildlife more than the oil hurt it. Is gasoline always bad? “A whale might think, ‘Thank God for petroleum,’ ” Safina writes; the end of demand for whale oil saved some whale species. Government officials may have sugarcoated the situation, the author supposes, but the Deepwater Horizon spill just did not do much environmental harm.