Paleoclimate of the American West, and what we know right now
I just finished reading two very good new readings in climate change. One tells you what you might want to know about the past, present and future – and it turns out, very wild – climate of the American West. The other is the perfect place to go for a general overview of what we know right now about anthropogenic climate change – something you might want to have handy when you go to Thanksgiving dinner with that climate-skeptic uncle or to a town meeting with your climate-change-denying congressman.
First, the past: The West Without Water
This ambitious book, written for a general audience, sets out to tell us the state of what we know about the past, present, and future climate of the American West, and the influence of that climate on the region’s environment and society.
It’s a big job, but authors B. Lynn Ingram, a professor of Earth and Planetary Science at U.C. Berkeley and Frances Malamud-Roam, Environmental Planner and Biologist with the California Department of Transportation manage it pretty well. The first section, “Floods and Droughts in Living Memory” reads almost like a thriller: did you know that in 1861-62 the city of Sacramento was under six feet of water for six months?
The meat of the book is the central section: “A Climate History of the American West,” in which we learn not only what paloeclimatologists have pieced together about the climate history of our region, we learn about the natural “archives” that have allowed them to do it, from ocean sediments in the Santa Barbara basin, to wetland sediments in Suisun Marsh, to bristlecone pine growth rings, to analysis of the tree stumps rooted on the floors of Lake Tahoe, Pyramid Lake and Mono Lake.
The take-away: We live in a region with a wild climate that alternates between drought and floods, a climate that could well become even wilder with the addition of human-caused climate change. And is a region where millions of people now live in towns and cities that are entirely dependent upon a regionwide plumbing system for their water, a plumbing system that was developed during a short period of relatively benign climate conditions.
Ingram writes, “The American West faces a climatic future that is predicted to become generally warmer and drier, with deeper droughts interspersed with larger and more frequent floods. The American West appears to be facing a potential climatic double-whammy: a cyclical return of drier conditions and new greenhouse-gas-induced warming.”
What we know now
Climate Change Evidence and Causes is also written for a general audience. A joint publication of the National Academy of Sciences and Great Britain’s Royal Society, the aim of the publication is to serve as “a key reference document for decision makers, policy makers, educators, and other individuals seeking authoritative answers about the current state of climate-change science.”
Most of the 24-page booklet consists of questions and answers about climate change, from the most basic – Is the climate warming? – to the more complex – What is ocean acidification and why does it matter? There is also an eight-page booklet summing up the basics of climate change that would be useful for a high school science teacher – or to give to that skeptical relative.