The document summarizes California's drought conditions in 2014 and provides historical context. It notes that as of March 2014, the Sierra snowpack was 31% of average and statewide rainfall was 29% of average. Over 90% of the state was in severe drought and 22% in exceptional drought. Tree ring data suggests historical droughts in California were longer and more severe than the "average" portrayed in the instrumental record, lasting decades rather than years. A ridge of high pressure has deflected storms away from California, exacerbating the drought. Various proposals and existing desalination facilities aim to help address water shortages, but brine disposal is a concern.
1. California’s Drought, 2014:
Monterey
As of March 1, 2014
• Sierra Snowpack Statewide: 31%
• Rainfall Statewide: 29%
- Central Coast 32%
• Percent Drought Area:
- 91% of State: Severe Drought
- 22% od State: Exceptional Drought
2. Droughts In The West Over Time
Cook et al. 2007. North American drought: Reconstructions, causes, and consequences. Earth-Science Reviews 81:93-
134.
Drier
Wetter
4. -3
-1
1
3
1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
Pacific Decadal Oscillation and Central Coast Rainfall
(1920 – 2014)
Year
SeaSurfaceAnomaly
Data From: PDO Index, University of Washington; Central Coast Rainfall, Western Regional Climate Center
1977 - 19981946 - 19761924 - 1945 1999 - 2014
CentralCoastRainfall
(Inches)
Warm
Warm
Cool Cool
0
10
20
30
40
50
1920 1930 1940 1950 1960 1970 1980 1990 2000 2010
19981983
El Nino
Severe Drought
(1976 -77)
Dust Bowl
(1924 – 35)
Severe Drought
(1924)
2013
Severe Drought
(2013 - 2014)
5. PDO
Rainfall
Smoothed Southwest
Rainfall and PDO Signals
From: Dai. 2013. Climate Dynamics. 41:633–646
1977 - 19981946 - 19761924 - 1945 1999 ->
Southwest US (30° N - 40° N, 105° W – 120° W)
2ndPCACoefficientofSST
6. California Drought:
Tree ring data suggests droughts were longer and more severe.
By Paul Rogers, 25 Jan 2014
Medieval Mega-droughts
240 years 180 years
900
Percent
Drought
Area 1850: California
Statehood
Wetter
Drier than
“Average”
2013, 2014 driest
years on record.
1000 1100 13001200 1400 17001500 1600 1800 1900 2000
From: Cook et al. 2010. Megadroughts in North America: placing IPCC projections of hydroclimatic change in a long-term
palaeoclimate context. JOURNAL OF QUATERNARY SCIENCE. 25(1) 48–61.
Year PDO Signal
20% -
60% -
40% -
Wet
Dry
7. Reverse Osmosis Desalination
Seawater
(or brackish)
RO
Membrane
Empty
Brine
(High Salt)
High Pressure
Drinking
Water
Sand City’s RO Filters
- 40% of cost comes from
electricity.
56%
44%
9. Monterey Bay Aq.
(Seawater Dilution)
Red Sea
40
Salinity and Marine Life
31405070 60
Ocean Salinity
(Parts per thousand, ppt)
Common
Marine Life
Dead
Sea
337
Salton Sea
49Mono Lake
79
Reverse Osmosis
Brine
(from seawater intake)
Marina Regional
Water Project
62 53
Sand City Plant
(Brackish Intake)
Monterey Bay
32 - 34
Santa Cruz Plant
(Proposed Wastewater Dilution)