Analysis of Societal Response in Urban Landscape Irrigation due to the Recent California Drought Utilizing Remotely Sensed Satellite and High Resolution Aerial NAIP Imagery
Abstract
California is currently amidst the most severe multi-year drought on record. Severe strains on water supply throughout the state have resulted in calls from water agencies and the Governor of California for extensive conservation. In Southern California, as much as 65% of daily water usage in single family homes goes towards outdoor use, primarily for grass lawns and landscaping. Therefore, the majority of the water conservation messaging has been targeted at turf removal and limiting outdoor irrigation. However, quantification of the effectiveness of these conservation campaigns and subsequent impacts on outdoor irrigation in large urban areas is difficult due to a lack of readily available in situ metering data separating indoor and outdoor use. Here we use a suite of high-resolution remotely sensed products to examine the impacts of the drought on irrigated vegetation over the Greater Los Angeles County. One-meter National Agriculture Imagery Program (NAIP) data from the United States Department of Agriculture and 30-meter Landsat data over Los Angeles is used to calculate the Normalized Difference Vegetation Index (NDVI). NDVI is compared between non-drought (2005, 2009, 2010) and drought years (2012, 2014). Declines in NDVI are typically manifested as browning of vegetation due to reduced irrigation, or the replacement of water intensive grass lawns with more native vegetation. Results suggest that changes in NDVI during the drought may be dependent on societal responses to water conservation campaigns. Our analysis suggests that disparities in plant greenness, a proxy of plant health, and total vegetated area exist between wealthy and poor communities, both prior to and during the drought. This disparity is likely to increase during drought periods, assuming wealthier communities are less likely to respond to increasing water rates and more stringent watering restrictions.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFM.H51H1595M
- Keywords:
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- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSESDE: 1655 Water cycles;
- GLOBAL CHANGEDE: 1855 Remote sensing;
- HYDROLOGYDE: 4313 Extreme events;
- NATURAL HAZARDS