Analysed the occurrence and usage of water resources(Groundwater,Rainfall,Precipitation) in the State and the possible steps that can be taken to curb the drought.
2. DROUGHT
Drought is an extended time when a region receives a deficiency in
its water supply, whether atmospheric, surface or ground water.
It is the absence of water for a long period of time, at a place where it
is considered ‘not normal’ compared to its usual conditions.
Generally, this occurs when a region receives consistently below
average precipitation.
We often do not see droughts as natural disasters like tornadoes,
hurricanes or floods, because they do not have the usual immediate
destructive ability, but they can be very catastrophic in the long run.
3. CAUSES OF DROUGHT ?
It can be caused by not receiving rain or snow over a period of time.
Droughts can occur when there is lack of ‘expected’ precipitation
Drying of Surface water flow. Surface waters may dry out if the flow
from their sources is affected.
Human factors-Deforestation will expose surface water to more
evaporation and also reduce the ability of the ground to hold water and
make it easier for desertification to occur
Global Warming – Warmer temperatures, often result in more dryness,
which also tend to speed up drought conditions.
4. CALIFORNIA
California is the third largest state in the U.S, by area.
It is the most populous state in the U.S.
If it were a country, California would be the 9th Largest economy in the
world and the 34th most populous.
At least half of the fruit produced in the United States is grown in California,
and the state also leads in the production of vegetables.
Agriculture contributes to 80 percent of its water use.
California has been the state with the largest water use in the US since the
USGS began compiling water-use data in 1950
An average Californian uses 196 GWPD compared to 98 GWPD by an
average American.
5. CALIFORNIA
California’s proximity to the Pacific Ocean and major mountain
ranges define the state’s hydro climate setting.
Most of the water vapor that provides the state’s precipitation comes
from the Pacific Ocean, as moist air moves over mountains such as
the Sierra Nevada or Transverse Ranges the air is lifted and cooled,
resulting in condensation and rain or snow.
Snowpack in the Cascade Range and Sierra Nevada contributes to
the runoff in the state’s largest rivers and to the groundwater basin
recharge that support much of California’s urban and agricultural
water use.
6. Much of California experiences a Mediterranean like climate with dry
summers that are warm or hot, and wet winters that are cold.
Westerly winds transport water vapor that provides winter
precipitation; summers are characterized by a blocking high pressure
zone that diverts atmospheric moisture away from the state.
On average, about 75 percent of the state’s average annual
precipitation of 23 inches falls between November and March, with 50
percent occurring between December and February.
Ultimately, drought in California stems from an absence of winter
precipitation. At the weather timescale this occurs when an
atmospheric high pressure ridge blocks winter storms from reaching
the state, shunting them to other areas.
Records of low rainfall and higher temperatures, vaporized its water
supply.
7. RIDICULOUSLY RESILIENT RIDGE
Ridiculously Resilient Ridge , the nickname given to a persistent region of
atmospheric ridge that occurred over the far northeastern Pacific
Ocean during 2013-2014.
This persistent ridging acts to "block" the prevailing mid-
latitude Westerlies, shifting the storm track northward and suppressing
extratropical cyclone (winter storm) activity along the West Coast of the
United States.
The Ridge comprises the western half of atmospheric ridge-trough
sequence brought persistent anomalous cold and precipitation to the eastern
half of North America during 2014 in addition to record-breaking warmth
and drought conditions in California.
This anomalous atmospheric feature disrupted the North Pacific storm
track during the winters of 2012-2013, 2013-2014 and 2014-2015,
resulting in extremely dry and warm conditions in California and along much
10. SNOW PACK
The state (and much of
the West) relies heavily on
snowpack each winter to
resupply surface water
streams and lakes.
Because of a lack of
winter storms and record
high temperatures this
past winter, snowpack in
California is at an all-
time low. This is the
fourth consecutive year
that the snowpack has
been below normal.
11. These three images show a portion of California's Central Valley (left side of the
images) and the neighboring Sierra Nevada mountains as viewed by Landsat in
February 2011, 2013, and 2014.
The reduced winter snowpack in the Sierra Nevada mountain range is concerning, as
snowpack, through runoff, provides about one-third of the water used by California's
cities and farms.
The decrease of winter snow cover can be seen in this progression of images. The
reduction of available water supplies in the Central Valley is also indicated by the
changing outlines of Folsom Lake, Camanche Reservoir, and other lakes and
reservoirs.
12. GROUND WATER
The Department of Water Resources estimates that groundwater
levels across most of the state have dropped 50 feet below historical
lows. In many areas in the San Joaquin Valley, groundwater basins are
more than 100 feet below previous historic levels. This overdraft
partially results from Californians withdrawing groundwater faster
than the rate of natural recharge.
During normal years, groundwater supplies between 30 and 40
percent of California’s water. But when surface water availability is
reduced during droughts, groundwater can account for closer to 60
percent of water used statewide.
Increasing temperatures will lead to earlier and reduced melting of
snowpack, which in turn reduces the quantity of available
groundwater.
16. Snowfall in December 2013 was less than 5
percent; 30 percent is average
Mount Shasta
Top left: November 2013
Bottom right: January 2014
17. DROUGHT EMERGENCY
Gov. Jerry Brown declared a state of emergency over a drought on Jan
1st 2014.
He called all Californians to conserve water in every way possible.
Brown urged residents to cut their water use by 20 percent, and asked
state agencies to conserve water.
Describing California's plight, the governor's office cited state officials
who say rivers and reservoirs are below record lows – and the state's
snowpack is at only 20 percent of its normal average for January.
California's state water board in May 2015 approved emergency
drought regulations that aim to slash water use in urban areas by
25%.The measures call for cities and water agencies to reduce water
usage by amounts ranging from 8% to 36%.
18. On April 1, 2015, the California Department of Water Resources measured the
statewide water content of Sierra snowpack at five percent of average for April 1st.
These levels are lower than any year in records going back to 1950.
The April 1 snowpack measurement is crucial because this is when the snowpack is
normally at its peak and begins to melt into streams and reservoirs. Snowpack,
through runoff, provides about one-third of the water used by California's cities and
farms.
California's 2014 Water Year, which ended September 30, 2014, was the third driest
in 119 years of record. It also was the warmest year on record
20. DESALINATION
It is the process of removing dissolved salts from water, producing
fresh water from seawater or brackish water.
The principle used is Reverse Osmosis.
San Diego is currently building the biggest desalination plant in the
western hemisphere to the tune of 1 Billion USD. It will make 204
Million liters of portable water daily and sell at a rate of $1 for every
616 lts.
The price is 80 % higher than San Diego pays for water from outside
the county. It will only cater to 10 % of the county’s needs. It requires
a lot of energy.
Conservation and recycling may be a better strategy.
21. SOLUTIONS
•Strict enforcement of water shortage contingency plans
•Judicious use of groundwater sources to meet requirements
•Farmers should trade water hungry crops for drought resistant crops
•Use of micro-sprinkling and drip irrigation, and doing laser leveling of fields
to reduce runoff
•Installation of water meters wherever needed and possible to regulate water
use
•Investing in public outreach campaigns to educate water users regarding
new restrictions and judicious use of water
•Incentives for replacing lawns with drought-resistant or native plants.
22. •Policy to encourage conservation by pricing water in tiers, depending on
water usage
•Moratorium on issuing new water service permits, a ban on draining and
refilling pools, and strict limits on outdoor watering, with penalties imposed
for violations
•Buying water from farmers north of the Sacramento Delta, who would fallow
their fields and profit from the sale of their water rather than their crop
•Possibly revisiting California's riparian water right laws (framed in the 19th
century) and make suitable amendments to suit the 21st century needs