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Q&A: Dr. Alex Hall

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Alex Hall

When climate scientist Dr. Alex Hall showed up to a recent climate change event at City Hall, he had his Brompton fold-up bike in tow and spoke to the audience about how he's heartened to see the explosion of interest in the subject. Well before climate change was ever a trending topic on Twitter, he was devoted to its study. As a professor in UCLA's Department of Atmospheric and Oceanic Sciences and a member of UCLA's Institute of the Environment and Sustainability (IoES), he teaches climate-related courses at the undergraduate and graduate levels, and he is also the faculty director of the UCLA Center for Climate Change Solutions and an acclaimed author of both global and regional climate studies. He has been a contributing author for International Panel on Climate Change (IPCC) reports and his regional work includes a series of studies that project climate impacts across Southern California. Asked to sum up his work in one sentence, he replied, "I work to reduce uncertainty in computer-based projections of future climate."

What inspired you on your career path?

Dr. Alex Hall: I always loved science. But when I was choosing which area of science to specialize in, environmental issues, especially climate change, seemed especially pressing. I love my work because it's so interesting and has so much societal relevance. I've also had great mentors along the way, amazing scientists who still inspire me. Suki Manabe was my PhD mentor [at Princeton]. He is one of the early pioneers in climate modeling, and he is a brilliant scientist. He also has a great sense of humor -- the perfect combination of serious and fun!

What are the key external factors that drive your work?

AH: In our regional climate change work, we're always looking to identify key vulnerabilities of human and natural systems to climate change. To a large degree, those vulnerabilities drive what aspects of climate change we focus on.

What kind of discoveries have you made in your work?

AH: My research group and I recently developed a new approach to producing very high resolution, neighborhood-scale climate projections. For the Los Angeles region, one interesting result from this was how much variation there is in projected warming across the region. Basically, if you're separated from the coast by some significant topography, you see more warming than near the coast. We knew global climate models project more warming in the interiors of continents than over the oceans, but we were a bit surprised just how sharp this contrast is in the Los Angeles region. Even the San Fernando Valley, only separated from the coast by the relatively low Santa Monica Mountains, sees somewhat more warming than coastal communities like Venice.

What are the barriers you face in your work?

AH: Because climate change affects such a wide variety of human and natural systems, understanding climate change impacts and responding to them isn't something climate scientists can do all by themselves. Expertise is needed from a variety of different disciplines, including ecology, hydrology, public health, engineering, law, policy, urban planning, and many, many others.

Universities are famous for their disciplinary silos, and there are institutional and cultural barriers that make it difficult for scholars from different silos to work together. That's one thing UCLA has made a serious commitment to changing, with our Sustainable LA Grand Challenge project. This project brings more than a hundred faculty from across campus together to get LA on renewable energy and local water while enhancing ecosystem and human health. My own Center for Climate Change Solutions at UCLAis trying to tackle this problem as well, by organizing interdisciplinary projects to better understand climate change impacts on water resources, ecosystems, and other areas.

Name a significant, little-known fact the every Californian should know.

AH: I think many Californians don't realize that more than half of residential water use in the state goes to watering lawns. Turf grasses are really thirsty because they aren't native to California and aren't adapted to our current climate, let alone the warmer climate we expect in the future. One of the simplest and easiest things we can do to adapt to climate change in California is replace our lawns with native plants. It would drastically reduce water use in our homes.

A genie grants you wishes to fight climate change. What do you ask for?

AH: If I had three wishes, I'd wish for what I see as the silver bullets that would help us reduce greenhouse-gas emissions in LA (and other cities, too). The first would be a true public transportation network that's rapid, efficient, comprehensive, and accessible to everyone. L.A. is getting there, but it would be great to accelerate the process. Second, I'd wish for rapid improvements to solar technology so that is efficient, inexpensive, and aesthetically pleasing. There's so much potential for rooftop solar in L.A., but still too many barriers to its widespread adoption. Finally, I'd wish for a major breakthrough in renewable energy storage, which would allow renewable sources like solar and wind to provide energy around the clock.

Be honest: are you hopeful or pessimistic? Tell us why.

AH: I am actually quite hopeful. Humanity has faced other daunting, seemingly intractable challenges in the past, and has overcome them. And it encourages me that even when global-scale action seems stalled, there are still ways to move forward. The world's cities collectively account for a quite large share (by some estimates, as much as three-quarters) of global greenhouse-gas emissions. And cities are able to make changes on their own and reduce emissions relatively quickly. L.A. is a great example of a city that is taking sustainability very seriously and taking action to allow people to get out of their cars through improved public transit and more walkable communities. I think people are starting to see that changes like this actually improve our quality of life.

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