Effect of Climate Change - By Anjali Patel (IGKV Raipur, C.G)

1. SUBMITTED TO:
Dr. PRATIBHA KATIYAR
professor
Deptt. of Plant Physiology
PRESENTED BY:
ANJALI PATEL
PhD (Previous year)
Deptt. Of Agronomy
COLLEGE OF AGRICULTURE
INDIRA GANDHI KRISHI VISHWAVIDYALAYA, RAIPUR

2. Contents
 What is Climate and Climate Change?
 Introduction
 Impacts of climate change
 Potential climate change impacts to water
 Impact on Monsoon
 Impact on hydrological cycle
 Impact on water availability
 Mitigation strategies to reduce the effect of climate
change
 Conclusion

3. What is Climate and Climate Change?
 Climate is defined by the average state of the
weather conditions prevailing in a region over
a long period of time.
 The Intergovernmental Panel on Climate
Change (IPCC) refers to climate change as
“the state of the climate that can be
identified statistically by changes in the
mean or the variability of its properties,
and that persists for an extended period,
typically decades or longer”.

4. INTRODUCTION
 Global and regional climate has been changing
as evidenced by temperature increase,
increase in rainfall intensity etc.
 The impacts of climate change primarily driven
by global warming are highly extensive,
complicated and uncertain.
 Availability and variability of water resources
will be affected by climate change effect.
 The impacts of climate change on water
resources have received much attention
globally specially in the last 30 years.
 Rainfall, the main driver of the hydrological
cycle, has been varying in the parts of the
world.

5. Impacts of climate change

6. Potential climate change impacts
to water
 Less snow, more
rain
 Increased winter
flooding
 Earlier snowmelt
 Lower summer
streamflows
 Increased stream
and lake
temperature
 Increased risk to
aquatic ecosystems
and fish species
•Longer, warmer
growing seasons
•Warming surface
waters
•Intense droughts
•Longer and more
severe fire seasons
•Increased insect
and disease

7. Impact on Monsoon

8. Of much greater interest to the agrarian societies of South Asia is
the effect of climate change on annual and intraseasonal
variations in the monsoon…
Intraseasonal
variability: during the
summer, active and
break periods of
intense and reduced
precipitation have a
dramatic impact on
water supplies
available for
agriculture.
Interannual
variability: seasonally
persistent floods or
droughts can be
devastating to the
Indian economy if not
correctly forecast.

9. Climate change may not manifest itself in simple
changes alone. Variations on decadal timescales can
also influence the monsoon system…
 Interdecadal variability: observed
relationships between the monsoon and the
El Niño-Southern Oscillation over the
Pacific have waxed and waned over the
last century. Some measure of ENSO is
often used in statistical forecasts of the
monsoon.
One version of the HadCM3 model suggests
that ENSO may change between distinct
regimes at 2xCO2.
The regimes and their impact on the monsoon
demonstrate that climate change may have
more profound effects than previously thought.

10. Rainfall variations across India
during 1813 – 2006
Sontakke, H.N. Singh, N.
Singh,
Indian Institute of Tropical
Meteorology, Research Report
No. PR-121, May 2008
Annual rainfall shows
decreasing
tendency in recent times over
~68% area of the country.

11. Impact on hydrological cycle

12. What is Hydrologic Cycle?
 The hydrologic or water cycle describes a
natural set of continuous and dynamic
processes through which water masses in
the form of liquid, vapor or solid, move,
circulate and are stored within the earth
system (IPCC, 2013).
 It defines the sequence of transitions
where the Earth’s water (i.e., oceanic,
cryospheric, and continental moisture)
evaporates into and travels in the
atmosphere, condenses to form clouds,
returns to the earth surface as
precipitation, runs off to the oceans as
streamflow, and ultimately evaporates

14. Impact of Climate Change on the
Hydrological Cycle
 Components of the Cycle Being
Impacted
◦ Impact on Precipitation
◦ Impact on Groundwater
◦ Impact on Evapotranspiration
◦ Impact on Hydrologic Hazards
 Floods and Streamflow
 Drought, Extreme Temperature and Storm

15. Impact on Precipitation
 While increasing heat is the primary
physical expression of climate change
on the terrestrial system, discerning the
effect of increasing heat on precipitation
is not systematic.
 However, the more frequent impact is
probably the high disorder in
precipitation patterns.

16. Impact on Groundwater
 The impact on groundwater system
may be described by referring to its
quality, quantity, and functionality.
 Under climate change, the disturbances
in the precipitation regime (yearly
precipitation amount concentrated in a
few precipitation events), combined
with land-cover degradation,
significantly alter ground water
recharge.

17. Impact on Evapotranspiration
 Evapotranspiration is a critical
component of the water cycle.
 Under climate change, the rise of global
temperature affects directly the at-
mospheric water demand (potential
evapotranspira-tion). Finally, the actual
moisture release in the atmosphere is
higher than normal.
 We can say that the trend of dryness is
remarkable across the globe.

18. Impact on Hydrologic Hazards
 Floods and Streamflow
There is strong evidence that the increase of flood
frequencies is related to the increasing trends of
extreme precipitation events.
 Drought, Extreme Temperature and
Storm
Drought may be simply comprehended as a natural
hazard which consists of a deficit of water relative
to need. However, the understanding of these
abnormal drought patterns may imply the
consideration of precipitation and temperature.

19. Types of Drought
 Meteorological drought: it is based on the degree of
dryness or rainfall deficit and the length of the dry period.
 Hydrological drought: it is based on the impact of rainfall
deficits on the water supply such as stream flow, reservoir
and lake levels, and ground water table decline.
 Agricultural drought: it refers to the impacts on
agriculture by factors such as rainfall deficits, soil water
deficits, reduced ground water or reservoir levels needed
for irrigation.
 Socioeconomic drought: it considers the impact of
drought conditions (meteorological, agricultural or
hydrological drought) on supply and demand of some
economic goods such as fruits, vegetables, grains and
meat.
 Physiological drought: a state in which plants are
unable to absorb water even though water may be freely
available. The condition can be caused by a high ionic
concentration in the water, so osmosis may not occur, by
low water temperature, or by over application of fertilizer.

21. Effect of climate change on
sea water intrusions
 Coastal regions are under a constant
threat of sea water intrusion. Major
reasons are:
 Expansion of oceans on warming
 Increase in discharge due to melting of
glaciers
 Excessive pumping due to human
settlements along the coasts
 Increased sea water intrusion results in
increased salinity of ground water
 It affects the water quality.

22. Sea-Level Rise
 Global sea-level change results mainly from two
processes, mostly related to recent climate
change, that alter the volume of water in the
global ocean through -
a) thermal expansion and
b) the exchange of water between oceans and
other reservoirs (glaciers and ice caps, ice
sheets, other land water reservoirs, including
through anthropogenic change in land hydrology
and the atmosphere).

23. Impact on water availability

24.  Climate change affect the ground water
recharge rate and depth of water table.
 Increased precipitation variation results
in decreased ground water recharge rate
in humid areas.
 Frequent heavy precipitation results in
exceeded infiltration capacity of the soil.

25. EFFECT OF CLIMATE CHANGE ON RECHARGE AND
DISCHARGE OF GROUNDWATER
 The changes in recharge patterns will affect
discharge patterns, which will have a direct
impact on groundwater supplies and on
surface water availability.
 In a cold or wet, the relationship is directly
proportional, i.e. high temperature results in
high precipitation and high recharge.
 Dry condition, the temperature and
precipitation are inversely related to each
other, as high temperature will result in less
rainfall.
 Changes in recharge patterns will also alter

26. Cont…
 An unconfined aquifer is recharged directly
by local rainfall, rivers, and lakes
 Unconfined aquifers are sensitive to local
climate change, and seawater intrusion.
 A confined aquifer, is normally recharged
from lakes, rivers, and rainfall that may occur
at distances ranging from a few kilometers to
thousands of kilometers.

27. Groundwater Discharge
 Under wet climate scenarios, run-off is
considered as a most sensitive
component and the combined effect of
increased precipitation and high discharge
will increase the risk of flooding.
 Under dry climate scenarios, recharge
will be the most sensitive component as
evapotranspiration will increase while both
recharge and discharge will decrease in
all seasons, resulting in decline in ground-
water level.

28. Impact on water quality
 Higher water temperature affects the
quality of water.
 Increased precipitation intensity and longer
periods of low flow decrease water quality.
 Many forms of water pollution, deposition
of pathogens, pesticides, salt etc. may
occur.
 Increases thermal stability results in
reduced oxygen concentration and
increased release of phosphorous from the
sediments.
 Increased erosion leads to mobilisation of

30. Impact of Climate Change on Water
Resources & Hydrologic Cycle

31. Mitigation strategies to reduce
the effect of climate change
 Structural adaptation: building infrastructures
which minimize the risk of climate change on
groundwater and increases the storage capacity
of aquifers. Eg: rainwater reservoirs, check
dams.
 Groundwater governance.
 Mapping of resources: gives idea about the
vulnerability and risk involved over time in an
area.
 Promoting afforestation.
 Carbon dioxide sequestration : trapping CO2 in
forests, grasslands etc.

32. CONCLUSION
•Although climate change has been widely
recognized, research on the impacts of climate
change on the groundwater system is relatively
limited.
•The impact of future climatic change may be
felt more severely in developing countries such
as India, whose economy is largely dependent
on agriculture and is already under stress due
to current population increase and associated
demands for energy, freshwater and food.
•Water availability and water quality are
fundamental issues for the 21st century.