Most climate maps break down the world into grid squares 200 kilometers wide. That's great for creating a regional picture, but too big a brush to paint what's happening at the city and neighborhood levels. New work coming out of the UCLA Department of Atmospheric and Oceanic Sciences greatly improves that resolution, predicting temperature changes in grid sections just two kilometers wide in the Los Angeles region.
The new report, Mid-Century Warming in the Los Angeles Region [PDF], finds that climate change will likely affect some parts of Los Angeles more heavily than others, with potential temperature increases of between 1.7 and 7.5 degrees Fahrenheit under a business-as-usual scenario. Inland areas and places at high elevation are predicted to see temperatures rise 20 to 50 percent more than areas near the coast or within the L.A. basin.
This more precise method of evaluation is seen as an important tool for planners and policymakers, who would like to have more precise information about how to respond to changing temperature levels within cities, and ideally, to pinpoint efforts aimed at reducing those potential impacts.
The report also predicts how, under various scenarios, different parts of Los Angeles would see more extreme heat days (those with temperatures above 95 degrees). Again, the results vary by area, with higher elevation areas taking a harder hit than coastal areas or neighborhoods within the basin. As the chart below shows, inland areas like Porter Ranch, 25 miles northwest of downtown L.A., could see extreme heat days jump from the current eight per year to more than 30. Places like Hollywood and downtown L.A. itself would see their extreme heat days increase from roughly one to three or four by mid-century.
Having this level of detail is especially important in a place like Los Angeles, where the topography is so varied that you can literally ski in the morning and have dinner (or maybe even lunch) on the beach in one day. Being able to estimate that the average temperature increase will be up to two degrees higher in one place than it will in another just a few miles away will enable more sensitive planning.
Photo credit: Marc Serota / Reuters