Water Cycle Change Over Time - Californian Drought 2012-2019

overview

semi-arid region

drought part of long-term trend, exacerbated by climate change and water management issues

water cycle changes: precipitation

rainfall dropped significantly, lower streamflows

below-average snowpack levels

climate change and global warming contributed to shifting weather patterns and more frequent dry periods

water cycle changes: snowpack reduction

snowpack in Sierra Nevada provides 1/3 of supply diminished drastically

snowmelt was delayed and reduced in volume, reduced flow into rivers/reservoirs

altered timing and availability of spring and summer water

water cycle changes: increased evaporation

higher temperatures means increased evaporation from soil, reservoirs and rivers

evaporation from agricultural fields and urban areas, greater water loss

temperature resulted in drier atmosphere, faster drying of soils

water cycle changes: increased wildfires

lack of rain and dry conditions, prone to wildfires

reducing runoff and snowmelt, so vegetation was drier and susceptible to ignition

exacerbated changes by destroying vegetation, reducing soil infiltration and increasing runoff in subsequent rains - flash floods

impacts on water resources: agriculture

major agricultural producer, significant effect on crop yields due to limited irrigation

impacts on water resources: hydroelectric power generation

hydroelectric plants relying on water reservoirs significantly impacted

lower water levels affecting electricity generation meant greater reliance of fossil fuels and solar energy

human response: increased use of recycled water

expanded use of recycled water for landscaping and industrial uses, reducing dependence on freshwater supplies

invested in desalination plants to reduce pressure on traditional freshwater resources

human response: sustainable land use

urban and agricultural areas promoting sustainable land practices - rainwater harvesting, improving irrigation techniques, more efficient crop production

efforts to restore wetlands and areas along riverbanks to improve natural water storage & reduce flood risk