ONE OF THE HIDDEN causes of the ongoing slaughter in Darfur, Sudan, is the advancing sands of the Sahara, likely triggered by man-made climate change. So say climate scientists. But there is a worrying counterargument: the real causes lie in the toxic politics of Sudan, and to even suggest climate is to blame is to excuse its perpetrators and collude with a government in Khartoum that oversees the genocide.

Of course, the causes of most conflicts, including this one, are multifaceted, and yet our debates about them are at root facile. We are likely to see many more such arguments as climate change gathers pace and makes its presence felt across wide areas of our social, ecological, meteorological, economic, political, and chemical landscapes. Nothing will be immune from the effects of climate change. Only rarely will its influence be uncontested or unmediated by other factors. We are going to have to get used to this.

There are too many books out now on climate change. And most, in their efforts to assert the primacy of global warming as an influence on our future world, overlook the more subtle but profound interplays. Even more sophisticated examinations of the importance of environmental change to civilizations (notably Jared Diamond’s Collapse) fall into the trap. There will probably not be “climate wars,” but there will be numerous conflicts where climate plays a role.

Stephan Faris’s Forecast, which begins in the killing fields of Darfur, is well worth the carbon footprint of its publication. By conceding that climate change is just one factor in the complex web of world affairs, he does not diminish its importance, but rather emphasizes how far its tentacles will extend.

This insight arises out of some sustained and impressive reportage by one of our leading correspondents on the affairs of the developing world. It is this perspective that gives the book its real power. From the ill-governed, poverty-stricken, and deforested island state of Haiti in the Caribbean to the disputed river valleys of the Indus in south Asia, from the vineyards of Napa Valley to the farmers’ frontier in the Amazon, at times Faris almost seems to undermine the importance of climatic influences. But read harder — and explore further, as he does — and it emerges in the most unlikely places. As he puts it: “The impact of climate change on a country is analogous to the effect of hunger on a person. If a starving man is shot while stealing a piece of bread, you wouldn’t say he died because he didn’t eat. But hunger played a role in his death.”

Climate change is entering our psyche in unexpected ways. In the poorer streets of London, England, Faris finds that the xenophobic British National Party has adopted climate change — and fears of the “flood” of environmental refugees it will likely generate — as a key part of its racist political platform. As he points out, the association of environmentalism with left-wing causes is a recent phenomenon. Go back before the 1960s, and conservation and conservatism share more than a common linguistic root. Hitler was an environmentalist. And visions of environmental purity played out in the eugenics movement of the same era. Fear of climate change will often drive events long before the reality. Out on the Florida Keys, Faris finds that decades before the waves wash away the coastal homes, insurance companies will do the job just as well by withdrawing coverage.

Sometimes the science presented in the book is a bit pat. We really don’t know if man-made climate change is driving an advancing Sahara, for instance. There are other theories, which involve other sorts of pollution and natural cycles of variability that repeatedly show up in the climate record of the Sahara. Nor do we know if desertification is likely to continue. Some of Darfur’s neighbors, including Niger, where many refugees have headed, have seen some wetter years recently. And can the World Health Organization really know that 2 percent of malaria cases today are due to climate change? I do not believe so.

But generally this is a skillful amalgam of reporting and analysis. Faris’s stories, from polar bear hunts around Hudson Bay to the melting glaciers of the Himalayas, are always about human as well as ecological affairs — and are far more compelling than any number of computer model simulations of climate change.

It is not the first time that someone has toured the world to root out how climate change is changing our lives. The pioneer work here was Mark Lynas’s High Tides. But Faris is the most perceptive so far about its growing place in our daily lives, our iconography, and, sometimes, our paranoias.