By John Schwartz
Global warming is posing such wide-ranging risks to humanity, involving so many types of phenomena, that by the end of this century some parts of the world could face as many as six climate-related crises at the same time, researchers say.
This chilling prospect is described in a paper published Monday in Nature Climate Change, a respected academic journal, that shows the effects of climate change across a broad spectrum of problems, including heat waves, wildfires, sea level rise, hurricanes, flooding, drought and shortages of clean water.
Such problems are already coming in combination, said the lead author, Camilo Mora of the University of Hawaii at Manoa. He noted that Florida had recently experienced extreme drought, record high temperatures and wildfires — and also Hurricane Michael, the powerful Category 4 storm that slammed into the Panhandle last month. Similarly, California is suffering through the worst wildfires the state has ever seen, as well as drought, extreme heat waves and degraded air quality that threatens the health of residents.
Things will get worse, the authors wrote. The paper projects future trendsand suggests that, by 2100, unless humanity takes forceful action to curb the greenhouse gas emissions that drive climate change, some tropical coastal areas of the planet, like the Atlantic coast of South and Central America, could be hit by as many as six crises at a time.
That prospect is “like a terror movie that is real,” Dr. Mora said.
The authors include a list of caveats about the research: Since it is a review of papers, it will reflect some of the potential biases of science in this area, which include the possibility that scientists might focus on negative effects more than positive ones; there is also a margin of uncertainty involved in discerning the imprint of climate change from natural variability.
New York can expect to be hit by four climate crises at a time by 2100 if carbon emissions continue at their current pace, the study says, but if emissions are cut significantly that number could be reduced to one. The troubled regions of the coastal tropics could see their number of concurrent hazards reduced from six to three.
The paper explores the ways that climate change intensifies hazards and describes the interconnected nature of such crises. Greenhouse gas emissions, by warming the atmosphere, can enhance drought in places that are normally dry, “ripening conditions for wildfires and heat waves,” the researchers say. In wetter areas, a warmer atmosphere retains more moisture and strengthens downpours, while higher sea levels increase storm surge and warmer ocean waters can contribute to the overall destructiveness of storms.