Impacts of climate change on snow accumulation and melting processes over mountainous regions in Northern California during the 21st century

K Ishida; N Ohara; A Ercan; S Jang; T Trinh; M L Kavvas; K Carr; M L Anderson

doi:10.1016/j.scitotenv.2019.05.255

Impacts of climate change on snow accumulation and melting processes over mountainous regions in Northern California during the 21st century

Sci Total Environ. 2019 Oct 1:685:104-115. doi: 10.1016/j.scitotenv.2019.05.255. Epub 2019 May 21.

Authors

K Ishida¹, N Ohara², A Ercan³, S Jang⁴, T Trinh⁵, M L Kavvas⁶, K Carr⁷, M L Anderson⁸

Affiliations

¹ Faculty of Advanced Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan. Electronic address: keiishida@kumamoto-u.ac.jp.
² Civil and Architectural Engineering, University of Wyoming, Laramie, WY 82071, USA. Electronic address: nohara1@uwyo.edu.
³ J.Amorocho Hydraulics Laboratory, Department of Civil and Environmental Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address: aercan@ucdavis.edu.
⁴ Korea Institute of Water and Environment, Korea Water Resources Corporation, Daejeon 305-730, South Korea. Electronic address: kwaterjang@kwater.or.kr.
⁵ Hydrologic Research Laboratory, Department of Civil and Environmental Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address: tqtrinh@ucdavis.edu.
⁶ J.Amorocho Hydraulics Laboratory, Department of Civil and Environmental Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA; Hydrologic Research Laboratory, Department of Civil and Environmental Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address: mlkavvas@ucdavis.edu.
⁷ J.Amorocho Hydraulics Laboratory, Department of Civil and Environmental Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA. Electronic address: kjcarr@ucdavis.edu.
⁸ California Department of Water Resources, Division of Flood Management, 3310 El Camino Ave Rm 200, Sacramento, CA 95821, USA. Electronic address: Michael.L.Anderson@water.ca.gov.

PMID: 31174110
DOI: 10.1016/j.scitotenv.2019.05.255

Abstract

A point-location-based analysis of future climate change impacts on snow accumulation and melting processes was conducted over three study watersheds in Northern California during a 90-year future period by means of snow regime projections. The snow regime projections were obtained by means of a physically-based snow model with dynamically downscaled future climate projections. Then, atmospheric and snow-related variables, and their interrelations during the 21st century were investigated to reveal future climate change impacts on snow accumulation and melting processes. The analysis shows large reductions in snow water equivalent (SWE), snowfall to precipitation (S/P) ratio, and snowmelt through the 21st century. Timing of the peak of the SWE and snowmelt will also change in the future. Meanwhile, the analysis in this study shows that air temperature rise will affect, but will not dominate the future change in snowmelt over the study watersheds. This result implies the importance of considering atmospheric variables other than air temperature, such as precipitation, shortwave radiation, relative humidity, and wind speed even if these variables will not clearly change during the 21st century.

Keywords: Air temperature; Future projections; Snow accumulation and melt; Snow water equivalent; Snow/precipitation ratio.