It had to happen eventually. With overwhelming scientific evidence today proving that global warming caused by human activities (more precisely, "anthropogenic climate change") is for real, a mainstream novel about the subject was perhaps overdue. "Ultimatum," by Matthew Glass, incorporates what we now know for certain is happening to the world around us. British author J.G. Ballard's 1960's quartet of end-of-the-world novels ("The Wind from Nowhere," "The Drowned World," "The Burning World" and "The Crystal World") still stand today as the genre classics (and are well worth reading if you can find them). "Ultimatum" is a decent, if somewhat unexciting, addition to the field of "global disaster" novels.
Writing a novel about global warming today is risky. In 1962, when Ballard penned "The Drowned World," the topic was pure science fiction. His imaginative story of submerged cities, verdant tropical lagoons in formerly temperate climes, and nature gone wild in "the forgotten paradises of the reborn Sun" was, at the time, merely an entertaining yarn with no more basis in reality than, say, faster-than-light travel or bug-eyed monsters. But today, global climate change is apparent to anyone who cares to look at the evidence.
It is impossible for a modern author to tackle the subject without immediately running afoul of politics and religion--the two forces that continue to tear the world apart today. Whether or not global warming is "real" is hotly debated along ideological and religious lines. Consequently, your opinion of "Ultimatum" will probably depend on your political and religious persuasion, and therefore on whether or not you believe the evidence. If you believe it, "Ultimatum" is a realistic tale that shows (or, at least, talks about) the consequences to America, and to the world, of failing to act decisively to reduce greenhouse gas emissions. If you don't believe the evidence, you'll probably dismiss "Ultimatum" as just another biased, left-wing diatribe from a liberal author--a Limey, no less--with a political axe to grind.
I won't go into the details of plot, setting, characterization and so on--other reviewers have covered these points nicely. However, I must point out that, for all of the author's obvious political acumen and passion for the subject, "Ultimatum" has many of the flaws of a first novel. For example, the characters are in no way distinct or delineated, and there are far too many of them for the reader to distinguish among them. I found myself constantly flipping back and forth--"Now who the heck is this person again?" But my biggest beef, and one that made it hard for me to get into the story at all, is that there is WAY too much dialogue and WAY too little action. Mr. Glass tends to relate unseen events by having characters talk about them endlessly, not by showing them, and almost all of the book consists of conversations among characters. His style is a little ponderous and didactic, and the book lacks the crispness and immediacy that a more experienced author might have brought to the party. With that said, if you tackle "Ultimatum" and can overlook its shortcomings, you will gain a better understanding of some of the real issues of global warming and of the political minefields involved in trying to solve the problem. I recommend it with reservations.