Glen M. MacDonald is director of the Institute of the Environment and Sustainability at UCLA, and a professor of geography and of ecology and evolutionary biology. Jon Christensen, a journalist-in-residence at the Institute, talked with Dr. MacDonald about his research on climate change, its causes and its impact on the environment and society, what climate change holds in store for California, and what the demise of the woolly mammoth could mean for us.
Jon Christensen: What are the biggest concerns that we should have about climate change in California?
Glen MacDonald: Fire and water! I work on both issues and it is not a pretty picture. I also worry about the impact of increasing temperatures on public health through heat stroke and diseases such as dengue fever. Nasty stuff. Heat stroke will likely have its greatest impact on those who cannot afford a lot of air-conditioning. Something like dengue, however, is more an equal opportunity pestilence. In fact, I did some work in Malaysia and saw that it was the more affluent areas with watered gardens and lots of houseplants that had the most trouble. All those irrigated microhabitats provided breeding places for the mosquitos.
Jon Christensen: How will climate change affect water in California?
Glen MacDonald: With increased temperatures and rates of evaporation and decreased precipitation in parts of the state and in the Colorado Basin we will face even more of a scramble to maintain a secure and steady supply for agriculture and our cities. The fact that the snowpack will be smaller and spring run-off more flashy means water managers really have their work cut out to capture the water that is available and have it ready for the long hot summers to come. This challenge may be compounded by the fact that when it does rain the storms will be more intense and hard to manage.
At the same time, we will also have too much water along the coast. As sea level rises coastal communities will face having too much of the salty kind flowing over them. The IPCC's sea-level projections have been pretty much bang on to what we have observed. Having a place on the current beachfront in the Colony at Malibu is not likely to be that attractive. Broad Beach is already facing serious issues. Challenging times ahead for some of the most expensive real estate in the world.
Jon Christensen:What about fires?
Glen MacDonald: The hot and dry conditions of the 21st century will produce greater fire hazard for the state no doubt. We are already seeing a series of record fires this past decade. Things like the Rim Fire are what it is going to be like in general. Fire suppression over the 20th century built up the fuel load in our forests and climate change provides just the right conditions to really stoke the flames. Watch out for your cabin in the woods at Mammoth or Lake Arrowhead. They could be in the thick of it!
Jon Christensen: You have studied what happened to the woolly mammoth, a once plentiful species that went extinct long ago during a period of changing climate. Should the fate of the woolly mammoth be a warning to us?
Glen MacDonald: Now, I actually am one of those people who do believe that there are important episodes of natural climate change in addition to the human induced kind. In fact, much of my own research is on natural climate change and its impacts, Some people have a thing for dinosaurs, but I have a real affection for the woolly mammoth, These things survived in absolutely brutal climates and environments. Millions of them live in northern Europe, across Asia, and into North America. Yet by about 10,000 years ago they had all but vanished from the continents and the last few died out on Wrangle Island off the coast of Siberia about 4,000 years ago. Our studies of their extinction have gathered thousands of pieces of evidence from things like radiocarbon dated tusks to the latest analysis of DNA preserved in frozen remains of these beasts. From that we can see that despite their toughness, wide geographic distribution, and relatively large numbers, climate change, along with habitat alteration, and a push from human hunters here and there was all it took to wipe them out. I take a look at climate change and the altered and disrupted habitat of the planet today and wonder how many species will make it through the 21st century and how many will join the mammoths.